Bill Kappel’s Snow Season Summary  

Snow Season Summary 2008 to 2009
July 1, 2006 to June 30, 2007
Lat 39.0994 N Lon 104.7636W El. 7371’

Summary Tables for the Season

Summary of the Snow Season’s Weather  

July 2007:
We received a wide variety of weather for the month of July around the region with heavy rain, hail, high temperatures, smoke, and even some remnants of a decaying hurricane.  For the month as a whole, temperatures were right about normal, with high temperatures ending above average and low temperatures below average.  Precipitation was close to average, but for many of us that all came in a couple of big storms, not the best scenario for provided moisture to our plants. 

July started off the same way June ended, warm and dry.  However, things began to change quickly, as higher levels of moisture began to work into the region.  This along with little waves of energy rotating through the atmosphere helped to trigger thunderstorms each day from the second to the 7^th, with one exception, the 4^th of July.  The strong storms developed during the early evening hours of the 3^rd, when a line of severs storms dropped heavy rain and large hail in a narrow line right along Highway 83 from County Line Road through the north side of the Springs.  Many residents under these storms picked up 1-2 inches of rain in less than an hour, and this of course led to some flash flooding in the area.  Several rounds of garden variety thunderstorms developed during the afternoon and evenings of the 5^th through the 7^th and when combined with general cloudy skies, cool temperatures, and light rain showers, helped add a significant amount of moisture to the parched soils.   

The second week of July started of stormy and wet, with heavy rain and hail for many of us on the Tuesday the 8^th.  The afternoon and evening storms on the 7^th and 8^th held down high temperatures below average, with upper 70’s to low 80’s common.  Moisture levels quickly dropped over the next few days and the storms disappeared.  Temperatures were well behaved for the next few days as well, with highs in the 80’s on the 9^th-11^th, then cooler air moved in on the 12^th and highs held in the low 70’s on Saturday and upper 70’s to low 80’s for Sunday the 13^th.  Making things even more pleasant was the fact that hardly a cloud was seen either day, making for a beautiful weekend. 

Fairly typical mid-July weather affected the region from the 14^th through the 20^th.  This included warm temperatures and scattered afternoon and evening thunderstorms.  Highs reached into the mid and upper 80’s during the entire period, which is right around to a little above normal.  Also, this week of July is on average our warmest week of the year, but it will be a while before you’ll really notice the difference.  Thunderstorms developed on several afternoons, with the strongest storms occurring 14^th, 17^th, and 18^th.  As usual, these were hit and miss, some areas picked up over an inch of rain and got hit by large hail, while others barely received enough to wet the ground.  As we move through the latter part of July and into August, afternoon and evening thunderstorms will become more common, as this is the time of the year when we receive the peak amounts of moisture associated with the Southwest Monsoon. 

The last week of the month saw the typical pattern of morning sunshine and afternoon clouds and scattered thunderstorms.  Temperatures were a little above average for the period with highs in the mid 80’s to low 90’s through the period.  Some areas received a good shot of rainfall while others missed out on the fun.  This is typical with summertime thunderstorms which affect small areas for short durations.  Therefore some of us get beneficial rain and others just some clouds.  The weather pattern across the region didn’t change much through the end of the month with one exception. The remnants of Hurricane Dolly, which moved onshore near Brownsville, TX, moved into New Mexico and southern Colorado on the 27^th and 28^th.  This brought with it higher levels of moisture and added lift to the atmosphere.  This allowed thunderstorms to develop that were a little more enhanced than would have happened otherwise. 

August 2008:
Temperatures ended right on average for the month, but don’t let that fool you, as high temperatures ranged from record highs in the 90’s during the first few days of the month, to record low highs in 50’s during the middle of the month.  Precipitation was well above average as a series of thunderstorms and heavy rains pounded the region starting on the 5^th and lasting off and on through the 24^th.  Most residents picked up 5-9 inches of rainfall, a good 30-50% above normal for the month.

The month started off hot and dry as high pressure built into the region from the southwest.  As this area of high pressure continued to strengthen, temperatures continued to warm, with highs touching record levels during the first few days of August, topping out in the low to mid 90’s from the 1^st through the 4^th.  Unfortunately for most of us these hot temperatures were accompanied by little to no rainfall.   

The weather pattern began made a dramatic change starting on the 5^th and lasting for the next few weeks, as higher levels of moisture began to move into the region.  This “juicy” air allowed strong to severe thunderstorms to develop almost daily.  This, combined with very weak winds up high in the atmosphere meant that these storms were able to drop heavy rain over the same area for extended periods of time.  The first round of heavy storms hammered areas just to the east of the Tri-Lakes, from Highway 83 east through Meridian Rd along Hodgen Rd, then south to Shoup Rd. This round of storms dropped more than 3 inches of rain in less than an hour, which led to lots of flash flooding,  Several rounds of afternoon and evening thunderstorms continued to develop over the next few days, and with all the clouds and storms around, temperatures were held to below average levels in the 70’s and 80’s. 

Wet and cool weather continued through the week of the 11^th, starting with the normal pattern of afternoon and evening thunderstorms and then transitioning to cold and wet, as an unusually strong area of low pressure moved through the region Friday the 15^th through Sunday 17^th.  Temperautres were at or slightly above normal for the first few days of the week with low to mid 80’s from the 11^th through the 13^th.  Then, Thursday the 14^th was a transition day as an area of low pressure moved into the region directly from southern Canada.  This storm brought cold temperatures, low clouds, fog, drizzle, rain, and even some hail.  This was more like a winter-type storm than a mid-August event.  And even though it moved in over the weekend probably ruining a few outdoor plans, it was sure nice to get some soaking rains.  Scattered thunderstorms continued to develop each afternoon and linger into the early evening hours through the 23^rd, as temperatures rebounded to normal levels behind the departing system.   

The weather pattern quieted down to end the month, as mild temperatures returned under mostly sunny to partly cloudy skies.  There were a few isolated storms around most afternoons, but for the majority of us, dry conditions prevailed from the 24^th through the 31^st. 
 
September 2008: 
Overall, a fairly quiet month around the region, with precipitation right about average and temperatures below average.  Most of the rainfall for the month accumulated during a 3-day period from the 10^th through the 12^th; otherwise the majority of the days were mostly sunny.  No snowfall was recorded, which is a little unusual as about one of every two Septembers receives at least a trace of snow sometime during the month.   Also noteworthy is the fact that we didn’t record our first sub-freezing low temperature.  This normally occurs by the 3^rd week of the month.  Even that no lows were below freezing, the overall average low temperature for the month was below average because we had so many clear nights which allowed for strong radiation cooling to bring overnight lows into the 30’s on 20 mornings. 

The month started off quiet and dry with high temperatures ranging from the upper 70’s on the 1^st to low 50’s on the 8^th.  We did have two cold front slide into the area, one on the 5^th which dropped high temperatures to the 50’s and one on the 8^th, which produced areas of low clouds, fog, and drizzle.  Otherwise, no significant weather was seen during the first week.  This change quickly as an unusually strong area of low pressure moved through the region during the second week of the month.  This storm brought another round of heavy rainfall to the region.  As has been the case sine July and August, this summer when it rain it pours, as most of our moisture since July has come in the form of heavy rain during four events, while the rest of the time has been fairly dry.   

This latest storm brought 1-2 inches of rainfall to the region, but that doesn’t tell the complete story.  Much heavier rain fell in and around downtown Colorado Springs, where a new all-time 24-hour rainfall record was established at the official recording station for Colorado Springs (at the airport).  There 4.97” of rain fell from Thursday evening into Friday evening.  This again illustrates how widely varying the rainfall can be during the summer months when convection is the primary process for producing precipitation.  Remember back in July when the Colorado Springs airport recorded the driest July on record (only .29” for the month), while we were hit with flash flooding and heavy rain and ended up with above average precipitation totals.  This type of extreme variability in rainfall amounts makes it almost useless to use a single station’s precipitation values and say they apply to the entire region.  In other words, those that would have you believe because the Colorado Springs airport official station is showing below average (or above average) precipitation for the year means that we are all in a drought (or are all wet) just don’t understand or have some other agenda. 

High pressure dominated the weather pattern throughout the last full week of summer and beginning of fall, resulting in sunny, quiet and mild weather.  High temperatures were in the 70s most afternoons, with overnight lows dropping to average levels, in the mid 30’s to low 40’s.  A quick moving band of showers did move through during the late afternoon and early evening hours on Saturday the 20^th.  Then on the afternoons and early evenings of the 26^th, 27^th, and 28^th thunderstorms and brief rains showers developed, bringing a little change to the region.  The last two days of the month were sunny, breezy, and cool behind a dry cold front, a fitting end to an overall quiet weather month.
   
October 2008:
Overall, pretty quiet weather during the month of October, with lots of sunshine interrupted with a couple of stormy periods.  Temperatures for the month were slightly below average and precipitation, including snowfall, was well below normal.  We did get our first snowfall of the season and several mornings of hard freezes.  A little unusual was the fact that the weather around Halloween was mild and quiet, although I don’t think trick-or-treaters were too unhappy. 

October started off much the same as September ended, sunny and mild.  Sunshine and warm temperatures were seen on the 1^st with highs hitting the mid 70’s.  The next two afternoons were more reminiscent of August, with morning sunshine giving way to isolated afternoon thunder and brief rain showers as highs remained well above average in the 70’s.  An organized area of low pressure finally began to affect the region on the 4^th with cooler temperatures and increasing clouds.  The full brunt of the system was felt on Sunday the 5^th, with a steady band of rain moving through with a few thunderstorms during the afternoon.  This band of showers and storms produced a quarter to a half an inch of rainfall.  The storm quickly departed the region, leaving behind a fairly quiet start to the second week of the month. 

Our first widespread hard freeze was felt across the region on the morning 7^th when temperatures dropped into the 20’s  This was about two weeks later than normal, although most (especially the tender plants) weren’t complaining.  Quiet, sunny, and seasonal conditions stuck around for the next few days, with highs moving from the upper 50’s on the 6^th to the upper 60’s and low 70’s on the 10^th.  This was all ahead of a complex weather system which affected the region from the afternoon 10^th through the 13^th as an area of low pressure set up shop over the Rocky Mountain region.  This storm brought quite a variety of weather, including heavy snow to Idaho, Utah, Wyoming, and Montana. However, for us here around the tri-Lakes, the moisture and cold air never came together at quite the same time.  Instead, we had a chilly, soaking rain on the 11^th with a quarter to a half inch accumulating as temperatures hovered in the low 40’s.  Then the cold air arrived in earnest during the afternoon of the 11^th, after the organized areas of moisture left.  This left behind a foggy cold, day on Sunday the 12^th.   

The third week of the month was a dry week around the region with plenty of sunshine and some gusty afternoon winds from the 13^th through the 19^th.  Temperatures fluctuated quite a bit throughout the week starting off on the cold side and ending the week above average.  High temperatures were only in the 40’s 13^th and 14^th, but steadily rose throughout the week reaching into the low and mid 70’s by the weekend.   

Finally, our first taste of winter arrived with as a strong cold front blasted through the area during the afternoon of the 21^st.  We were first greeted with showers and thunderstorms, then as the colder air continued to filter in, rain mixed with and changed to snow.  Most of us were accumulating snow by around 7pm.  Snow continued to fly off and on through the early morning hours, and as winds picked up late on the 21^st, some of the snow began to blow around.  The next morning’s commute was a little icy, as much of the snow melted on the pavement initially, and then froze into a layer of ice overnight.  Temperautres were chilly the next day as well, with highs barely reaching above freezing.  Morning low temperatures were generally in the low 20’s and upper teens for the next couple of mornings.  Sunshine did return quickly after the system departed the region on the 22^nd, with temperatures moderating through the 25^th when highs reached all the way into the low 70’s.  A dry cold front did knock temperatures back down on the 26^th, but this was short lived, as mild and sunny weather returned for the rest of the month.  
 
November 2008:
Most of November was quiet and mild, before a big blast of winter moved in to end the month and make for an exciting thanksgiving weekend.  Overall, temperatures were above normal and precipitation was well above normal.   

Much above normal temperatures greeted us to start off the month of November, with highs reaching into the 60’s and low 70’s.  Even more surprising is the fact that overnight lows stayed well above freezing on the mornings of the 2^nd and 3^rd.  Gusty winds and scattered clouds helped to keep us very mild at night.  These temperatures were a good 15-20 degrees above normal.  Of course, “normal” or “average” temperatures and weather are simply the mean between extremes, so you know at some point we will even out these warm/dry extremes with the other side of the coin. 

A weak cold front did produce a couple flurries on the 4^th and dropped high temperatures in the low 40’s that afternoon.  With the clear skies that evening and the chilly air in place, morning lows on the 5^th dipped into the low teens and upper single digits and highs once again were slightly below normal, only hitting the mid 40’s.  Seasonal conditions returned for the rest of the week with high in the 50’s and low in the 20’s.  Overall, pretty typical for early November, as this has been one of driest and least active months over the last few years.

More typical November weather affected the Palmer Divide from the 10^th through the 16^th.  This included a couple quick shots of snow, with sunshine and mild temperatures in between.  Monday started off on the cold side with 1-2” of snow and highs temperatures holding in the 30’s.  Temperatures rose through the 40’s all the way to the 60’s over the next couple of days under lots of sunshine.  This quickly melted most of the snow as well.  The next cold front arrived early in the morning on the 14^th and snow began to fly just before sunrise. This storm dropped another 1-3 inches around the region, and kept temperatures below freezing all day on the 14^th.  Skies cleared quickly that evening, and overnight lows dipped into the single digits around much of the area on the morning of the 15^th.  Sunshine returned again quickly for the weekend, and highs rebounded into the 60’s by Sunday the 16^th, again melting most of the snow. 

Another quiet week from November 17-23^rd, with temperatures above average except for one day and dry conditions.  From the 17^th through the 19^th, temperatures were in the 60’s to near 70, with numerous record highs set around the Front Range of Colorado on the afternoon of the 18^th.  A sharp cold front did bring a quick and drastic change to the warm temperatures late on the 19^th through the morning of the 21^st.  Low clouds, fog, freezing drizzle, and a few flurries developed across the region as this shallow layer of cold air settled in on the 20^th.  This made for an icy commute as ice coated many of the roadways.  Westerly winds soon kicked this cold air mass out of the region, with mild and dry conditions returning for the weekend. 

The last week of the month started off harmless enough, making for no major travel headaches for those headed out of town.  This changed quickly however, as winter made a powerful appearance during the Thanksgiving holiday weekend, as several rounds of snow developed in the area.  The first cold front moved in during the early morning hours of turkey day, with temperatures staying at or below freezing all day-making for an even better excuse to stay inside, watch football, enjoy the family and friends, and eat lots of food.  Less than an inch of snow fell during the evening hours, but this did add a nice wintry feel to the area.  Temperatures warmed briefly into the low 40’s the next afternoon as we enjoyed a brief respite between storms.  More light snow developed during the evening of the 28^th and continued through the early morning of the 29^th.  More snow showers blew in during the afternoon of the 29^th, and then the real fun developed later that evening and continued into the 30^th.  Heavy snow bands formed late on the 29^th and into the 30^th, as a very strong jet stream moved directly overhead.  This allowed for very efficient lift in the atmosphere.  This lift in the upper atmosphere (~20,000 feet above the ground) combined with a strong north/northeast flow at the surface to produce orographically enhanced snow bands as the winds blow up the north side of the Palmer Divide.  There was plenty of moisture and cold air to work with as well, all combining to give us our first big snow of the season.  By then end of the day on the 30^th, most had accumulated an impressive 10-20” of fresh snowfall in less than 24 hours.  This sure helped to make of the deficit we had been running up until this point in a hurry, disappear.

December 2008:
Temperatures were near normal for the month, with many swings between cold Canadian air masses and warm westerly winds.  Precipitation, including snowfall, was below average for the month.  However, the big snowfall from November 30^th combined with a few reinforcing shots of snow meant that many areas kept a nice snowpack throughout the month. 

The first week of December had some wintry weather interspersed with brief mild and sunny periods.  A trace of snow fell on the 1^st as temperatures stayed below normal.  Then warmer and windy weather moved in that evening as winds gusted overnight and kept temperatures above freezing.  Highs on the 2^nd hit the mid and upper 50’s.  However, as usual, this was ahead of a cold front, which dropped through the region just before midnight on the 2^nd.  Temperatures on the 3^rd and 4^th were chilly, with highs staying below freezing on the 3^rd and holding only in the teens on the 4^th as a reinforcing shot of cold air moved in.  In fact, the high of 15°F on the 4^th occurred just after midnight and temperatures tumbled into the single digits during the day with light snow.   

Warming, westerly winds moved back in over the next few days, scouring out the cold air and returning temperatures back to above normal levels in the 40’s and 50’s.  The next cold front arrived during the afternoon of the 8^th, accompanied by more cold air and moisture.  This time most of us picked up 3-6 inches of snow from the afternoon of the 8^th through the morning of the 9^th.  High temperatures held in the teens again on the 9^th, even with sunshine returning.  The roller coaster ride continued as the cold air moved out to the east and temperatures rose back into the 40’s from the 10^th through the 13^th under mostly sunny skies.  Then the next even colder airmass moved in just after midnight on the 14^th.  This Arctic front brought with it the coldest air of the season so far.  Temperatures were in the low 30’s when the front arrived then tumbled quickly to the single digits and continued to dip below zero during the day.  A couple inches of snow accompanied this chilly air mass as well. 

Temperatures continued to bounce up and down every few days during the week of Christmas around the region, with highs hitting the low to mid 40’s on the 22^nd and the 28^th and holding below freezing on 23^rd, 24^th, and 27^th.  Several powerful Pacific storms slammed into Colorado, but because the origin of these storms was from the west/southwest, we missed out on all the fun here on the Front Range.  Instead, western Colorado and the mountains picked up lots of snow.  Several areas in the San Juan Mountains accumulated over 4 feet of snow during the week!  We did have a couple of brief snowfalls around the area on the 23^rd and 26^th, but that was about it. 

The month started off dominated by a strong ridge of high pressure.  This led to the proverbial “January thaw for much of the first week of January, only briefly interrupted by a quick shot of snow and cold.  Temperatures jumped into the 40’s and low 50’s on the 1^st and 2^nd of the month, accompanied by gusty winds out of the west/southwest.  A quick moving cold front did make an appearance during the first weekend of the month, racing through the region during the morning of the 3^rd with temperatures tumbling to the teens through the afternoon.  This storm had enough cold air and moisture to produce plenty of light, fluffy snow as well.  With most of us picking up 2-4 inches before the snow stopped on Sunday the 4^th.  The cold air stuck around as well, with highs only touching the low teens on the afternoon of the 4^th.  

The first full week of January saw a mixed bag of weather, ranging from snow and cold to breezy and mild.  The week started off on the chilly side as a storm system was leaving the region.  Highs held in the low 30’s on the 5^th and 6^th under mostly sunny skies.  Mild air quickly moved in the next day on west/southwest winds and temperatures jumped into the 40’s and 50’s.  We also had our typical bouts of mountain wave clouds during these days a strong winds roared over the Rockies and produced the spectacular cloud formations where air currents were forced to rise and fall over the mountains like water running over a rough river bottom.  The next cold front arrived during the morning hours of the 9^th and brought a quick shot of 1-3 inches of snow.  Temperatures held near normal levels with highs in the 30’s through the rest of the weekend under mostly sunny to partly cloudy skies.  This fast flow, with quickly changing air masses racing over the region, from mild to cold, is very common for January and ensures that the weather pattern around here this time of the year never gets to stagnant. 

Winter was in full force to start off the week of the 12^th, but ended more like summer.  Snow and blowing snow started things off on Monday, with 4-6 inches accumulating around the area.  This storm cleared the region quickly, with sunshine returning not only for the next day, bur for the rest of the week.  Initially, temperatures were slow to warm, as there was plenty of fresh snow to reflect sunlight and take energy out of the atmosphere that would normally go into heating the air.  This changed by the end of the week, as a very strong ridge of high pressure developed off the West Coast and slowly edged towards Colorado.  Temperatures rose to above normal levels on Saturday and Sunday, with highs in the upper 40’s and low 50’s as westerly winds kicked in.   

Clear and mild weather started off the week of the 19^th, with temperatures well above normal as highs hit the 50’s and even low 60’s under sunny skies.  Some areas around the Front Range hit the low 70’s during this period.  Wintry weather did return by the latter half of the week as temperatures dropped back to normal as a couple of shallow, cold air masses moved in. These produced areas of low clouds, fog, and flurries.  However, because the air masses were so shallow, they retreated off the Palmer Divide by late morning on the 23^rd and 24^th.  This left us mostly sunny and allowing temperatures to hit the 40’s while lower elevations around us were stuck in the 20’s.  A more organized storm system began to affect the region by the end of the weekend.  This brought the coldest air of the month to the region on the 26^th and 27^th.  Temperatures only reached into the high singles digits during the afternoon of the 27^th after morning lows started off well below zero.  A few inches of fresh snow accompanied this cold air as well, but as has been the case most of the month, this cold air didn’t stick around long.  High pressure built back in to end the month, giving us mostly sunny skies and mild temperatures on the 30^th and 31^st.   
  
February 2009:
As has been the case most of the 2008-2009 winter season in the region, temperatures were above normal and precipitation was below normal.  Most of February was dry and sunny, with generally pleasant conditions (of course that depends on your individual definition of pleasant weather).  The low amounts of snowfall during the month, while unusual, is not too significant since February is normally one of the driest months of the year anyway.   Hopefully, March and April will be more “normal”, which would mean plenty of snow to get things green for spring. 

The first full week of February was dry and mild with sunshine and temperatures in the 40’s and 50’s through from Monday the 2^nd through Saturday the 6^th.  A quick, but powerful storm system then moved through the region on Sunday the 7^th.  However, this storm moved through so quick that winds were never able to turn upslope for the Front Range long enough to bring any substantial moisture.  Instead, we got a quick shot of snow later Sunday the 6^th, cooler temperatures, and strong winds.  This pattern is typical for a La Nina year which we are experiencing right now, which creates a powerful Polar Jet Stream.  This in turn races storms outs of the Gulf of Alaska, drags cold air from Canada and hammer the central and eastern United States.  So far this winter, many places from the upper Midwest through the Southeast and East Coast have experienced record snowfall and record cold.  We of course have been right on the edge of all this, with the action staying just to our east. 

Active weather affected the region during the second week of February as several strong Pacific storms moved through the region. However, because the origin of the storms was from the west/northwest, the mountains were the main beneficiary of the moisture, as we received on light amounts of snow and brief intrusions of cold air.  During the week, most of us picked up 2-4 inches of fresh snowfall, mainly on the 10^th and the 13^th.  Most of this melted quickly in areas that received sunshine as the sun angle continued to get stronger as we head toward spring.  Temperatures were held to slightly below average levels for the week, with highs in the 30’s and low 40’s.  The coldest day of the week was the 13^th with highs holding in the 20’s with 1-2 inches of snow falling during the early morning hours. 

Quiet, dry, and mild weather continued from the 16^th through the 22^nd, with one quick shot of cool weather and light snow during the evening of the 20^th.  Temperatures overall were above average, with highs in the 40’s and 50’s through the week.  Skies were mostly sunny for the beginning of the week and to start the weekend, with plenty of high and mid level clouds on Sunday. 

Then month ended with weather that was a microcosm of the month, with several days of sunny and dry weather interrupted by a quick moving cold front on the 27^th which dropped a little less than an inch of snow.
   
March 2009: 
The first two thirds of March continued the trend we saw in February of dry and mild conditions, as temperatures were well above average and very little moisture moved into the region.  A welcome pattern change did take place starting around the 23^rd of the month and brought with it below normal temperatures and several rounds of refreshing snowfall.  This of course included the blizzard which slammed into the region on the 26^th.  Overall, the month was warmer than normal and a little drier than normal. We did make up most of the moisture deficit during the last week of the month, which is good news for plants that are just starting to grow. 

Warm and windy weather greeted us to start off March, continuing the trend we saw for most of February.  From the 2^nd through the 8^th, temperatures were above normal each afternoon except for the 7^th.  High temperatures reached well into the 60’s, nearly touching 70 on the 2^nd, as high pressure built into the region from the Southwest.  This warm, dry air mass combined with westerly winds to push temperatures to near record levels.  A storm system began to approach the region from the west towards the middle of the week and this really kicked winds up quite a bit around the region.  The strong winds, combined with dry conditions produced hazardous fire weather conditions, but we made it through un-scorched.  This storm sent a cold front through the region during the evening of the 6^th and temperatures were held in the 30’s on the 7^th.  Areas of snow showers, heavy at times, developed by late morning of the 7^th and continued off and on as the system passed through producing some much needed moisture with 1-2 inches of snow falling throughout the area.  However, this system was a quick mover and we dried out very quickly with sunshine and mild conditions melting most of the snow on Sunday the 8^th. 

Monday the 9^th started of with above normal temperatures and breezy conditions as highs hit the low 50’s.  A weak cold front did move through that evening and a little snow fell during the morning of the 10^th.  Most of us only picked up a dusting to 1 inch however, certainly not enough to do much good.  Temperatures remained cool over the next two days with highs holding in the low 40’s, slightly below normal for this time of the year.  Another quick moving front produced a short lived snow shower during the morning of the 13^th.  With a cold air mass in place and clear skies, low temperatures the next morning were chilly, in the single digits to low teens.  Warm and dry air quickly followed again however, as high pressure built back into the area from the west.  This sent temperatures through the 50’s and into the 60’s for the weekend.   

The week of the 16^th was warm and dry around the region, with plenty of sunshine and breezy conditions.  Of course, this wasn’t a huge surprise, as most of the last two months have been this way.  Temperatures were above normal for the week, with highs well into the 60’s on the 16^th and 17^th, then dipping briefly into the 50’s on the 18^th and 19^th, with more warmth returning for the weekend.  Highs hit the mid to upper 60’s Friday through Sunday, making for a very pleasant weekend and start to Spring. 

The pattern changed quickly to end the month as a deep trough of low pressure and associated cold air developed over the Pacific Northwest and sent several waves of energy through the region.  The first front moved through during the early morning of the 23^rd with some light snow dusting the ground.  We just missed out on a big storm with this one, as the low pressure moved about 100 miles too far to the north for us, otherwise we would have seen blizzard conditions and over a foot of snow.  High temperatures were held in the 40’s that afternoon.  Over the next two days two more disturbances moved through and each produced a round of light snow, which melted quickly in the strong March sunshine.   

But a bigger, much more powerful storm was building at this same time, riding a strong jet stream through the Intermountain west towards the Four Corners.  This time, unlike a few days before, the storm took a more favorable track, with the low pressure riding along the Colorado/New Mexico border.  This brought a round of heavy, wind driven snow to the region from late on the morning of the 26^th through the morning of the 27^th.  This storm produced blizzard conditions for several hours on the afternoon of the 26^th and brought the region to a standstill.  Temperatures also tumbled with the cold front, dropping from the 20’s in the morning to the single digits by late afternoon.  Not bad for late March.  Most areas accumulated 10-15 inches of fresh snowfall, and .50-1 inch of liquid.  Just what we needed around here as we head into growing season.  High pressure briefly built in behind this departing storm, bringing lots of sunshine for the weekend.  Temperatures were slow to warm however, as much of the sun’s energy was deflected by the fresh snow and what made it to the ground was used to melt snow instead of warming the air.  We did manage to hit the 50’s for highs on Sunday however, making for a pleasant day.  Another powerful storm moved in on the morning of the 30^th.  This one again took a more northerly track and moved through very quickly.  Therefore, we only picked up a quick 1-3 inches of snow during the morning as the main front blasted through.  Temperatures were cold with this storm again, with daytime highs not reaching out of the 20’s.  Sunshine returned for the last day of the month and after a chilly start, highs reached back to the 40’s.

 April 2008:
As is typical around the Tri-Lakes region the transition from winter to spring is never smooth.  This was the case during the first week of April as we were greeted by everything from sun to snow.  The month started off on the cold side with light snow on the 1^st and high temperatures only in the 30’s.  Temperatures warmed the next day under mostly sunny to partly cloudy skies as highs hit the 50’s.  But more cold air moved in overnight and low clouds, fog, freezing drizzle, and flurries started us off on the 3^rd.  This cold air quickly retreated as we warmed into the 50’s and 60’s from the 4^th through the 6^th.  More cool, unsettled weather returned for the 7^th with snow showers across the area during the afternoon.

 Winter tried to hold for most of the week of the 7^th with measurable snowfall occurring on the 7^th and the 9^th through the 12^th.  Most of us received 4-8 inches during this timeframe, however, as is usual this time of the year, anytime the sun appeared the snow quickly disappeared.  The strongest storm occurred on the 10^th as an area of low pressure deepened over eastern Colorado and western Kansas.  This developed a very strong pressure gradient across the area, producing very strong northerly winds.  Snow began to fall steadily that morning and continued through the early evening.  This combined with the strong winds produced blizzard conditions at times.  Just the day before, as the first affects of this system began to move into the region on the 9^th, we saw a little bit of everything around the area.  Snow showers, plain old rain, thunderstorms, and fog all occurred at some point on the 9^th, just about what you would expect for the middle of April.  During the week high temperatures ranged from the low 30’s to the high 50’s, a little below normal for this time of the year. 

Quiet, “spring-like” weather greeted us for most of the 3^rd week of the month.  The week started off on the warm side with highs jumping into the 70’s on the 14^th and 15^th along with sunny skies.  Only some gusty winds took away from the warmth.  These were the warmest temperatures we’d send since late October.  Oh, but just when you thought it was safe to put the snow shovel away, a storm system moved through the region by early the next morning.  A cold front pushed over the area around 2:30am on the 16^th and we said goodbye to the 70’s and hello to snow.  This storm brought 4-8 inches of snow to most of us from the morning of the 16^th to the morning of the 17^th.  With temperatures holding in the 30’s both afternoons.  Temperatures did quickly rebound behind the system under sunny skies, as highs reached back into the 60’s for the rest of the week and through the weekend.  Again, only gusty winds each afternoon put a damper on the otherwise quiet weather. 

The first full week of May started off a little wet and cool behind a departing storm system.  The first three days of the month saw drear conditions with low clouds, fog, drizzle, and rain showers.  Temperatures were oh so close to snow, with highs in the low 40’s and lows in the low to mid 30s.  Right on the heels of this storm was some windy and mild weather moved in, as highs reached all the way into the upper 70’s on the 6^th and 7^th-a few areas did touch the low 80’s during the afternoon of the 7^th.  This warmth and sunshine really got things turning green around the area, as plants enjoyed the bountiful moisture left behind during April.  This warmth was ahead of a weak storm system which moved through overnight on the 7^th into the morning of the 8^th.  This dropped the temperature back below normal levels, with highs in the upper 50’s and low 60’s.  Winds turned to more of an upslope direction as we headed into the weekend of the 9^th.  This allowed extensive areas of low clouds, fog, drizzle, and light rain showers to develop, especially on the 9^th and 10^th.   

A bit of an up and down week temperature wise from the 11^th through the 17^th, but overall pretty pleasant.  Temperatures swung from the low 60’s on the afternoon of the 11^th to the upper 70’s and low 80’s the next afternoon as southwesterly winds kicked in.  This was ahead of a weak storm that moved through and dropped temperatures back down the 60’s the next two afternoons.  Warmth returned again on the 15^th, before another cool front brought low clouds, fog, and drizzle on the 16^th and kept highs only in the 50’s.  But the last day of the weekend saw a beautiful rebound as highs jumped back into the upper 70’s under sunny skies.   

The week of the 18^th started off more like summer than spring, as highs hit the 80’s area-wide for the first time this season on the 18^th and 19^th.  And, much like summer, afternoon thunderstorms developed each day, dropping some quick ¼ to ½ inch amounts of rain around the region.  Cooler unsettled conditions then moved in for the remainder of the week, with temperatures dropping from the 70’s on the 20^th to the 50’s on the 21^st, and then holding in the 60’s through the holiday weekend.  Each day saw plenty of clouds, fog, thunderstorms, and rain, with most of us picking up and inch or two for the week.  Of course, this has helped things get awfully green, and when combined with the abundant moisture since late March, we are now above normal for precipitation for the year and for the snow season.  Unfortunately, those who had outdoor plans for Memorial Day weekend didn’t have the best weather, but I guess it could have been worse, at least it wasn’t snowing. 

The last week of the month was right about normal, with highs ranging from the upper 50’s on the 26^th to the low and mid 70’s from the 28^th through the 31^st.  Typical diurnal patterns set up as well, with morning sunshine giving way to afternoon clouds and scattered thunderstorms.  The strongest of the storms did produce areas of heavy rain on the afternoon and evenings of the 30^th and 31^st. 

June 2009:
As was the case across the majority of the US (especially the East Coast where many records were set for the coldest June on record i.e. New York, Boston) temperatures were well below normal for the month, averaging more than 2° below normal.  The cool temperatures were most prevalent during the first two thirds of June.  Along with the cool temperatures, precipitation was above normal. 

Cool and wet was the story to start off June with rain falling each day from the 1^st through the 4^th.  The month started off with some strong storms on the 1^st with a few areas of heavy rain around the region.  Cold, upslope conditions moved in the next two days, with low clouds, fog, rain, and highs only in the 40’s and 50’s.  Clearing developed the next day, but there was still plenty of moisture around to fuel storms, some if which turned severe during the afternoon of the 4^th.  These produced some large hail and heavy rain right over the Black forest area around 4pm.  Drier and warmer conditions moved in the next few days, with high rebounding into the mid 70’s on Friday and Saturday.  Overall for the week, many of us picked up 1-2 inches of rainfall, adding to our above average amounts and keeping things green around the area. 

Summer officially started at 1045pm on the 20^th and pretty much up until that point we haven’t experienced much summer-like weather.  The week of the 7^th saw a continuation of the cool and moist conditions with highs holding well below average, generally in the 60’s.  Morning lows were also chilly, even touching the freezing mark on the morning of the 4^th.  Along with the cool temperatures, each afternoon from the 7^th through the 14^th saw showers and thunderstorms.  A few areas did see some severe storms as well, including a couple of tornadoes around Denver on the 7^th.  The strongest storms around here were in the 13^th and 14^th.  Most of us received brief heavy rain and hail some of it large enough to damage some plants.  A severe storm again developed on the afternoon of the 15^th just north of the El Paso County line.  This storm brought a tornado just north of the county line from just west of Highway 83 through just south of the town of Elbert.  Drier and slightly warmer air began to move into the region through Father’s Day weekend.  Highs reached back into the 70’s from the 16^th through the first day of summer on the 21^st.  There was one exception, Saturday the 20^th saw plenty of clouds move in from the south with scattered showers.  This weather pattern held highs only in the low 60’s.  But gorgeous weather returned just in time for Father’s Day, with sunshine and highs in the upper 70’s.   

Warm temperatures stuck around to end the month with highs holding slightly above average, mainly in the low to mid 80’s.  This was the product of an area of high pressure building in from the south, the Monsoon High.  Of course, this Monsoon High not only brings a rainy season to the Desert Southwest, but also allows for high levels of moisture to move into Colorado.  And this was the case during the last week of the month.  Afternoon thunderstorms developed each day, some of them strong to severe, with heavy rain and hail the main problems.  This wet weather certainly helped keep things green around the region.

Station Location, Topography, and Climate

The weather station location is approximately 3 miles north of the crest of the Palmer Divide, just ½ mile east of the intersection of Highways 83 and Highway 105.  I utilize a wireless Davis Vantage Pro weather station which includes a fan aspirated radiational shield and a heated rain gauge.  Several other meteorological instruments are used for backup and verification purposes and include two 4” rain gauges, and a Taylor Min/Max thermometer.  For snow measurement, I use a 36” snow stick and a snowboard for snow depth measurement and new snow fall totals, as well as standard measuring through the station location with a ruler.  Readings are taken at midnight local time each day and represent 24 hour conditions from midnight to midnight local time (Mountain Time Zone) with the exception of heavy snowfall events were readings are taken every six hours, with a 24 hour summary.  Geographically, the Palmer Divide separates Colorado Springs (~15 miles south) from Denver (~30 miles north) as a low, broad ridge generally rising 1000’ to 2000’ above these surrounding cities.  Directly to the west, the Rampart Range rises over 9500’, with the high Rockies rising to over 14000’ a little further to the west.  Many of the mountain ranges that run through central Colorado are oriented in a north south direction, perpendicular to the prevailing wind patters.  This greatly affects the weather and climate in the region, by sapping approaching systems from the west of their moisture and facilitating downslope wind events, which cause drying and warming.  To the east, the topography gradually slopes down to just under 4000’ along the Kansas border over a distance of 100 miles.  This rise in elevations from east to west along the Front Range aids in lifting air masses and helps to produce clouds and precipitation.  This condition is referred to as upslope, and generally leads to the coldest and snowiest conditions during the fall, winter, and spring months. The Palmer Divide is generally covered with Ponderosa pine above the 7000’ elevation.  Top elevations on the divide are around 7600’, with scattered buttes that rise to between 7700’ and 7800’along the Douglas and El Paso county lines.  The highest point is Bald Mountain, with a top elevation of 7881’.  The Palmer Divide has a dramatic effect on the local weather and climate of the region and extraordinary temperature and precipitation gradients are often observed within single storms and throughout the year when compared to Colorado Springs and Denver. Because of the high elevation of the divide and its location continental location, snow is often observed as early as September and as late as May.  In extreme cases, snow may fall in late August or early June.  The dry and generally sunny climate aids, along with rapidly transitioning air masses, aid in melting snowpack rapidly.  Therefore, transportation is rarely affected for more than a few days at a time because of snowfall.  Weather across the area is characterized by rapid changes, with periods of the same air mass types (cold/warm and/or wet/dry), lasting generally less than 2-5 days at a time.  Springtime is usually the wettest and snowiest time of the season, with fall a close second.  The mid winter period, December through February, is generally the driest and coldest time of the year, but because of the high snow to water ratio, snowfall amounts are similar or exceed the fall months (September through November Cold air surges from the northern high plains of North America and Canada often blast throw the region and bank up against the Palmer Divide and the Front Range bringing dramatic drops in temperatures, gusty winds, and stratiform precipitation (generally snow or freezing drizzle depending on the depth of the cold airmass) during the fall, winter, and spring.  Storms accompanied by southerly winds also bring moisture to the area, but have less affect on the north side of the divide because of weak downsloping (drying) effects.  Storms moving in from the west or southwest are mainly wind producers as they down slope off the Front Range to the west, causing the airmass to dry and warm adiabatically.  Because of the topography of the surrounding region, wide variations over short time frames are common during the snow season.  Generally, a cold surge will push through the area with a brief shot of upslope flow, which enhances precipitation, gusty north/northeast winds, and cooler temperatures.  Often west/northwest winds will follow the surges, bringing drier and warmer weather quickly to the region.  Therefore, snowfall, although a common occurrence, usually does not stay on the ground for long periods of time, except in the shaded areas.  Major storms, which can lead to blizzards in the area, most often develop when an area of low pressure develops on the lee side of the Rocky Mountains over the east central plains of Colorado or northern New Mexico.  The biggest snowstorms occur when these storms tap in moisture from the Gulf of Mexico and become cut off from the main westerly flow, sitting in the same region for several days.  This was the case during the March 17-20th, 2003 Blizzard.   These storms may or may not be accompanied with cold, arctic air masses, but often produce tight pressure gradients between areas of high and low pressure, with strong sustained winds the result.  When the winds are in a favorable “upslope” direction, when combined with other atmospheric processes, precipitation is enhanced and cools the air through the process of orographic lift and evaporative cooling processes. The coldest air of the winter season moves through the region when strong areas of Arctic high pressure move out of Canada, down through the central plains, producing north to northeast surface winds (“upslope winds) through the area.  However, these air masses are usually low in moisture content, and snowfall is usually no more than a few inches with high snow to water ratios (often 20:1 or higher).  Generally the cold air masses modify and /or move out of the area within a few days, but sometimes the can last up to a week producing low clouds, fog and snow showers.  This results in the coldest high temperatures of the winter season, where highs may remain in the teens and twenties for several days in a row.

In contrast to the cold and snow scenarios, warm and windy weather is not uncommon during the snow season.  The classic “Chinook” winds are common along the Front Range, including the Palmer Divide, and especially prevalent along and west of Interstate 25.  This occurs when Colorado is under a strong west/southwest flow aloft, with an inversion above the high mountains to the west, creating an ideal condition for the winds to mix down to the surface through turbulent mixing and mountain wave activity.  Wind speeds can often reach over 100mph across portions of the foothills of the Front Range, with the area around the Air Force Academy being a favored spot locally.  The Palmer Divide generally does not receive the strongest of the winds gusts, but temperatures still warm dramatically and relative humidities drop.  This occurs through compressional heating of the air mass as it descends and warm dry adiabatically at approximately 5.4F per 1000’ descended off the mountains to the west.  These “Chinook” winds (Native American for snow eater), are extremely affective at melting and evaporating moisture, whether it be rain or snow.  Looking at the daily temperature graphs for the winter season reveals these patterns of cold air intrusions quickly followed by “Chinook type winds and above normal temperatures.  

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07/03/2009 12:46 PM