Category Archives: Colorado Weather

Beautiful Tuesday, Cooler Wednesday, Big Snow Monday?

Variable weatherWe’re in the typical rollercoaster weather pattern that we usually see in the spring.  Tuesday was beautiful with a high of 68 degrees in Thornton.  Today will be a bit cooler as we reach 62 or so and that cooling trend should continue into the weekend.  A small disturbance could bring some minor snow accumulations to the area on Friday. 

Looking a bit further ahead, big changes could be in store for Sunday night and into Monday.  We are currently tracking a major Pacific storm system that is working its way west and if it tracks over the state, significant snowfall could result.  This far out the models are pretty inconsistent – some show it hitting us, others show it tracking much farther south into New Mexico. 

Snow & Blowing Snow Advisory Issued – Changes Are Here!

Snow on the way!Updated, Sunday, 3/2/08 @ 4:20pm – The storm has pretty much passed to the south of the Thornton area at this time.  The NWS says they will keep the Snow & Blowing Snow Advisory in effect until 8:00pm but there is little cause for concern on our side of town.  Any lingering showers should be confined south of I-76 and I-70.  Look for clearing skies tonight and a cool but decent day tomorrow.  Our next chance for precipitation should be into Wednesday but at this time that doesn’t look like it will amount to much. 

Updated, Sunday, 3/2/08 @ 2:00pm – After a bit of a lull things started picking back up for a while.  Winds continue to blow quite a bit and more snow is falling.  As previously mentioned, it is difficult to measure with how much it is blowing and drifting.  The National Weather Service guidelines say to take an average and pretty much make a “best guess” so that is what we do – call it 4.1″ of snow thus far today. 

Areas south continue to get the worst of the storm, particularly from Park and Jefferson counties east through Douglas and Elbert counties.  Blizzard conditions exist in these areas and do stretch north into eastern Adams county and to Limon.  Travel is not advised in these areas.

Radar does seem to indicate that the storm is slowly moving out and we should start seeing a decrease in intensity on the north side of town in the next couple of hours. 

Speaking of blizzards…  As of yet, this storm has not been classified as an official one – at least in the metro area.  By National Weather Service definition, a blizzard has winds of 35mph or greater and blowing snow that reduces visibilities to 1/4 mile or less for more than 3 hours.  Today, while the wind has been nasty, speeds have  been a bit erratic and we haven’t  had the sustained speeds to meet the definition.  Further, snowfall rates for the most part haven’t caused that severe of visibility issues.   Areas south and east of Denver however do appear to meet the criteria.

Updated, Sunday, 3/2/08 @ 8:40am – Fast and furious would be a good description of this storm.  The wind is the biggest thing right now causing drifting.  In our area depending on where you measure you can have anywhere from 1/2″ to 5″ which makes it pretty difficult to get an accurate measurement.  Radar does currently show that the worst of the storm has passed us by so it should continue to taper off although the wind will be with us for a while. 

Below are a few pictures we took at around 6:40 this morning as the worst of the snow was falling.

The ThorntonWeather.com sensor suite in the snow.  A view of the ThorntonWeather.com backyard.  A view of the ThorntonWeather.com backyard.  A view of the ThorntonWeather.com street.

Updated, Sunday, 3/2/08 @ 5:25am – The storm is here!  Snow has started falling in the north Thornton area just in the last 15 minutes.  Coupled with it are extremely high and dangerous winds.  The winds started building about an hour ago as the storm approached and reached a crescendo just before 5:00am when we recorded a ThorntonWeather.com record wind gust of 46mph.  This shatters the old record of 40mph.  Current average windspeeds are above 30mph which is quite high.

Radar is showing the front moving south across the area and conditions should continue to deteriorate as we get closer to sunrise and as the morning progresses.  Please rememeber that there is a Snow & Blowing Snow Advisory in effect until 8:00pm tonight.  A snow and blowing snow advisory means that visibilities will be limited due to a combination of falling and blowing snow. Use caution when traveling, especially in open areas.

Saturday, 3/1/08 @ 11:00pm – At 9:51pm tonight the National Weather Service issued a Snow & Blowing Snow Advisory for much of central Colorado and the central and northern mountains.  This goes into effect at 5:00am Sunday through 8:00pm.  Areas affected do include the Denver metro area.  Current models are indicating a stronger than expected upslope with this storm which will help slow it down as it moves through the area. 

Rain and snow showers could start to appear after 2:00am, changing to mostly snow by dawn.  By the end of the day Sunday we could see between three and five inches of snow in Thornton.  However, the ground is pretty warm thanks to the nice weather in recent days so a lot of it won’t stick.  The wind could cause some minor drifting and higher accumulations.   The south metro area and the Palmer Divide could see some significant accumulations and driving conditions will deteriorate quickly so if you are heading that way, please be aware.

This is of course quite a change compared to today (Saturday) when DIA reached a new record high for this date of 74 – the old record was 73.  Up north in Thornton we were a bit warmer with a high of 75.7.  We hope everyone enjoyed the warmth because change is coming!  🙂

March 2008 Weather Preview Now Available

March 2008 PreviewMarch in Denver typically means frequent and rapid weather changes. The days grow longer and we start enjoying more sunshine and sometimes summer-like weather. However, on occasion arctic air masses can still force their way south into Colorado dropping temperatures quickly and markedly.  Occasional thunderstorms do start to happen in March as well.

To see what to expect in the coming month, click here to view our March 2008 Preview.

Dry winter forecasts? Buried in the snow!

Dry winter?  Not here!An interesting article in the Denver Post today talks about how the forecasts for a dry winter have been way off the mark (thus far).  Even as recently as a month ago NOAA was saying that La Nina was going to wreak havoc and dry things out severely.  Yet today the mountains continue to have an amazing amount of snowpack with every basin well above normal. 

Meteorologist Klaus Wolter told the Denver Post that recent failures of their predictions may be traced to climate change.  Wolter said, “So we have two years in a row here where the atmosphere does not behave as we expect.  Maybe global changes are pulling the rug out from underneath us. We may not know the answer for 10 years, . . . but one pet answer is that you should get more variability with global change.”

 There it is!  You knew it was coming!  If all else fails, blame global warming!  🙂 

In all seriousness, assuming things continue as they have been, the concern now shifts not from drought but to possible flooding this spring.  Emergency planners are keeping a close eye and a fast run-off could not only lead to a loss of good, usable water but it could also cause a lot of problems. 

Despite the mountains of snow in the mountains, here on the plains we haven’t been quite as fortunate.  In the metro area, the historical seasonal average through the end of February is 39.6 inches of snow.  As of this morning (2/14), thus far this season ThorntonWeather.com has recorded 33.0 nches and the National Weather Service puts the official Denver measurement at 35.5 inches.  This puts us below average but there are still 15 days left in this month to catch up. 

 Please click here to view the entire Denver Post article:  Dry winter forecasts miss mark.

Latest Snowpack Reports Continue to Hold Promise

Snowpack above normalSnowpack reports as of this morning continue to hold great promise for Colorado.  All of the major basins are above average with the exception of the South Platte.  Another major snowstorm is hitting the mountains today and yet another is forecast for Wednesday.  We can only hope this pattern continues and NOAA’s forecasts of a dry first quarter don’t hold true.

It would however be nice if some of that moisture would move out onto the front range and into the Denver area and the plains.  There is a chance for a bit of snow in the metro area tomorrow and again on Wednesday although right now it doesn’t look like they will amount to much.

Colorado SNOTEL Snowpack Update Report
Based on Mountain Data from NRCS SNOTEL Sites
**Provisional data, subject to revision**
Data based on the first reading of the day (typically 00:00) for Sunday, January 27, 2008
Basin
Site Name
Elev
(ft)
Snow Water Equivalent Percent of
Current
(in)
Today’s
Average
(in)
Avg
Peak
(in)
Avg
Peak
Date
Today’s
Average
Avg
Peak
GUNNISON RIVER BASIN
Basin-wide percent of average 132 72
UPPER COLORADO RIVER BASIN
Basin-wide percent of average 114 61
SOUTH PLATTE RIVER BASIN
Basin-wide percent of average 93 49
LARAMIE AND NORTH PLATTE RIVER BASINS
Basin-wide percent of average 99 54
YAMPA AND WHITE RIVER BASINS
Basin-wide percent of average 99 56
ARKANSAS RIVER BASIN
Basin-wide percent of average 148 80
UPPER RIO GRANDE BASIN
Basin-wide percent of average 150 83
SAN MIGUEL, DOLORES, ANIMAS AND SAN JUAN RIVER BASINS
Basin-wide percent of average 141 78

Storm Chaser Convention Coming to Denver

Storm Chaser Convention Coming to DenverFebruary 15th -17th Denver will play host to the 10th Annual National Storm Chaser Convention.  The event will be held at the Raddison Hotel at I-225 and Parker Road (3200 South Parker Road).  Most notably, the keynote speakers will be Dr. Josh Wurman and Sean Casey who appeared in the recently aired Discovery Channel special, Storm Chasers.  This is a great opportunity for weather enthusiasts to share storm stories, learn more about severe weather and storm chasing, see new weather gadgetry and hear from some of the experts in weather related fields. 

To learn more, please visit the National Storm Chaser Convention website at:  http://chaserconvention.com

State Lucky Thus Far – Dry Months Ahead According to NOAA

Dry Months Ahead?Klaus Wolter, a meteorologist affiliated with the University of Colorado and the National Oceanic and Atmospheric Administration continues to promise a dry winter.  In an article today in the Rocky Mountain News he says, “I think we should count our blessings. We got lucky” in regards to the amount of moisture the state has seen thus far.

According to Wolter, the La Nina weather pattern present in the Pacific will persist resulting in storms tracking north of our state.  The good news though is that snowpack thus far is above normal statewide and even if their predictions bear out, we should be okay come summer.  Here are the latest readings as of today:

           S N O W  -  P R E C I P I T A T I O N    U P D A T E 
  
              Based on Mountain Data from NRCS SNOTEL Sites 
                    As of MONDAY: JANUARY 14 , 2008 
----------------------------------------------------------------------------- 
STATE                                                      PERCENT OF AVERAGE 
  RIVER BASIN                                     Number   Snow Water  Accum 
                                                 of Sites  Equivalent  Precip 
-----------------------------------------------------------------------------
COLORADO 
  GUNNISON RIVER BASIN ......................... 11 of 13     144       137 
  UPPER COLORADO RIVER BASIN ................... 27 of 29     119       124 
  SOUTH PLATTE RIVER BASIN ..................... 15 of 15     105       101 
  LARAMIE AND NORTH PLATTE RIVER BASINS ........ 13 of 13     101       109 
  YAMPA AND WHITE RIVER BASINS ................. 17 of 19     102       111 
  ARKANSAS RIVER BASIN .........................  5 of  9     141       124 
  UPPER RIO GRANDE BASIN .......................  9 of 13     158       144 
  SAN MIGUEL, DOLORES, ANIMAS 
     AND SAN JUAN RIVER BASINS ................. 14 of 16     153       135

We of course hope the forecasters are wrong just like they have been about the last two hurricane seasons

Please click here for the full Rocky Mountain News Article. 

Avalanche Danger High – One Dies in Recent Days

Avalanche danger.Recent snows along with high winds have raised the avalanche danger in the high country to “considerable” in many areas according to the Colorado Avalanche Information Center.  This was highlighted yesterday when a 27 year old man was killed just outside of Vail in an area known as the East Vail Chutes.  This is the second avalanche death of the season, the first being on December 2nd in Larimer County.  In the most recent case, these skiers had done everything right including having avalanche beacons but that was not enough. 

Avalanche Danger - 01/05/08

Everyone who intends to ski or hike in the high country, particularly outside of established areas, needs to be aware of the danger avalanches pose.  Recent weather has made the conditions ripe for these events.  The Forest Service National Avalanche Center points out that nearly all avalanches that involve people are triggered by the victims themselves or a member of their party.  The good news about that is that means that education can help to reduce the number of accidents we see each year.  To learn more, please see:

More Snow on the Way!

Snow on the way!After receiving a few inches of snow in the metro area on Christmas Day (3.6 in Thornton), another round is on the way and it has the potential to be pretty bad.  At 4:56am this morning, the National Weather Service issued a Winter Storm Watch for the entire Front Range. 

It is pretty unusual for them to issue a warning this far in advance unless they are confident it is going to hit and hit pretty hard.  4 – 8 inches are currently predicted with the potential for locally heaver amounts.  With as cold as it has been and is expected to stay for the next few days, this could get ugly.  Please plan your travel accordingly and be safe out there!

A few Christmas snowfall notes, from the National Weather Service: 

It appears that there may be a new daily snowfall for Denver for Christmas Day. The data in the link below extends back to 1900.  The 2.4 inches recorded today at 6 AM will beat the 1.7 inches set in 1912.  After dusting off some old records here at the National Weather Service office we discovered that 6.2 inches of snowfall was recorded on December 25, 1894.   We also found that prior to 1905 snowfall was recorded from 8 PM to 8 PM. From Jan 1905 to May 1999 snowfall data was from midnight to midnight. Since May 1999, snowfall data has been recorded from 6 AM to 6 AM.  The snow in 1894 began around 8 PM on the 24th and ended  around 2 PM on the 25th. The data for December 25, 2007 will show 2.4 inches recorded at 6 AM.  The remainder of the snow that fell today will be reflected on the data for the December 26.  It will be for the period from 6 AM on the 25th to 6 AM on the 26th. So did we have a record or not? It all depends on how you interpret  the data.  No matter how you look at it, Christmas day 2007 will be memorable.  Click here to check the Christmas day statistics  for snowfall from 1900 to 2006.

On a related note…  When you look at the measurements for snowfall that we make here at ThorntonWeather.com, those are typically total accumulations for the day we actually received the snow, up until 9:00pm or so.  The National Weather Service standard of 6:00am to 6:00am measurements is fine but are not what most folks expect.  As mentioned above, the 6:00am measurements from yesterday showed 2.4 inches of snow in Denver but obviously more than that fell throughout the day.  We feel that providing a total measurement for the day the snow actually feel is more in line with what folks expect and think of. 

Christmas Day Snow!

Christmas is here!As the kids wake up early this morning to see what Santa left them, we are seeing a bit of a nasty storm system move across the area.  The National Weather Service has issued a Snow and Blowing Snow Advisory that will remain in effect until 5:00pm Christmas Day.  Forecast models are a bit unclear as to how much snow we can expect – anywhere from one to five inches depending on which models we look at.  The biggest problem will be the wind blowing things around and causing travel issues for those visiting folks on the holiday.  Be sure to be safe and as always, stay tuned to ThorntonWeather.com for the latest.

Current Advisories

Current Forecast