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March preview: Biggest snow month also brings much milder temperatures

The past two months have brought periods of extreme cold but not a lot of snow to Denver.  March however is our snowiest month and may bring a turnaround in those numbers.  It also typically brings much warmer temperatures.

March is historically Denver’s snowiest month and brings about 20% of our annual snowfall.  Heavy, wet spring snow storms can oftentimes bring the entire month’s snowfall total in one monstrous snow.

We also start the transition to spring and severe weather season and the month typically brings our first thunderstorms of the year.  Temperatures climb throughout the month and by the end our average daytime highs are near 60 degrees.

For a complete look at what lies ahead in March 2014, click here.

February 2014 top shots: Monthly photo slideshow

February started with a shot of snow in Thornton. (Jason McNeil)
February started with a shot of snow in Thornton. (Jason McNeil)

The month of February is one that begins a transition to warmer temperatures and oftentimes lacks snowfall.  Nevertheless, Mother Nature oftentimes offers stunning scenes to be captured in imagery as we see in our February 2014 slideshow.

  • Slideshow updated February 28, 2014

Showcasing images captured by ThorntonWeather.com readers as well as some of our own, our monthly slideshow covers the entire gamut of weather-related imagery.  Sunsets, sunrises, wildlife and of course snow are vividly depicted.

Throughout the month we will gather the images sent to us via email or shared with us via our various social media outlets and post them in the slideshow below.

To learn more about getting your photos added to our monthly slideshow, click here. 

Click the play button below and sit back and enjoy the images.

Video: NASA animation shows polar vortex and its far reaching effects

NASA's Atmospheric Infrared Sounder (AIRS) instrument on NASA's Aqua spacecraft  shows the cold air pushed down from the Arctic in January 2014. (NASA)
NASA’s Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua spacecraft shows the cold air pushed down from the Arctic in January 2014. (NASA)

Unseasonably cold weather gripped much of the nation in January and brought a term to public’s consciousness they may not have heard before: polar vortex.  As explained in a video from NASA, the ‘stretching’ of the vortex was responsible for the record-setting cold seen last month.

NASA writes:

This movie of temperature observations from NASA’s Atmospheric Infrared Sounder (AIRS) instrument on NASA’s Aqua spacecraft depicts the first major North American weather event of 2014: cold air moving out of the Arctic and south to cover much of the continent. The temperatures shown are at a pressure of 850 hectopascals (hPa, formerly knows as millibars; sea level pressure is normally around 1000 hPa). Pressures of 850 hPa correspond to an altitude of about 3,000 feet (1 kilometer) above sea level. The temperatures in the movie range from about minus 18 degrees Fahrenheit (245 Kelvin or minus 28 degrees Celsius) to warmer than 66 degrees Fahrenheit (290 Kelvin or about 17 degrees Celsius). The very coldest temperatures in purples and blues are minus 18 to 17 degrees Fahrenheit (minus 28 to about minus 8 degrees Celsius).

The most obvious feature of the movie is the tongue of cold air moving out of Canada and southward to cover much of the eastern United States during early January 2014. This event was covered extensively in the media, and introduced the term ‘polar vortex’ to a broader audience.

This global perspective illustrates some features not noted in all the recent media attention. Perhaps most obvious: this is not a global phenomenon. The eastern half of the United States includes only about one percent of the total surface area of the planet (about two million of 197 million square miles). One advantage of satellite observations, as from AIRS, is coverage of the entire planet. A truly global perspective is required when studying variations in climate, and this event must be compared against a number of other phenomena occurring around the planet. Note that Alaska and northern Eurasia were warm during this period of unusual cold over the eastern United States.

Photo: Bald eagle and afternoon iridescent clouds

One of our friends was hanging out along the South Platte again this afternoon.  Had to shoot pictures into the sun but with the iridescent clouds in the background it looks really cool.

Cloud iridescence is caused by clouds (usually cirrus) that have small water droplets or ice crystals in them causing the light to be diffracted, or spread out. The phenomena is much like the rainbow colors seen with oil in water.

Remember we are always looking for pics of just about anything to add to our monthly slideshow.  Be sure to email or post them so we can add them. Check out this month’s slideshow here.

A bald eagles rests in a tree along the South Platte River. (ThorntonWeather.com)
A bald eagles rests in a tree along the South Platte River. (ThorntonWeather.com)

Denver sets record coldest high temperature for February 6

Record Cold TemperaturesThe big chill continued on Thursday as for the second day in a row the Mile High City’s high temperature set a record as the coldest for the date.

As officially measured at DIA, Denver’s high temperature today was 1 degree.  That easily bested the previous record low maximum for February 6 of 5 degrees set in 1929 and years prior.

The mark was an improvement, albeit a slight one, over yesterday’s high of 1 degree below zero which also set a record.

Here in Thornton we fared slightly better with our high temperature topping out at 4 degrees today and 1.9 degrees on Wednesday.

Warmer weather is on the way as the cold Arctic air mass is expected to be pushed out tomorrow.  Temperatures on Friday should climb above freezing for the first time in eight days.

January 2014 weather recap: Near average temps but well above normal snowfall

January 2014 could be remembered as a month that brought a weather rollercoaster.  Looking back it seems as if we were constantly jumping between mild temperatures to cold to warmth and back to cold again.

The month started out cooler than normal for the first two days with a light shot of snow on New Year’s Day.  Temperatures then shot into the 60s on the 3rd but were followed by colder temperatures and more snow on the 4th.  On the 5th we registered our coldest day of the month.

From the 7th to the 16th we experienced relatively calm conditions and only very light snow on one day.  We saw above normal temperatures from the 15th to the 21st.  Two cold days followed with snow falling on the 23rd.

Alternating above-normal and below-normal temperatures closed out the month.  Four of the last five days saw snowfall.

Thornton recorded an average monthly temperature of 31.3 degrees.  This was slightly higher than Denver’s official recording of 31.2 degrees.  Both were slightly above the historical average January temperature of 30.7 degrees.

Temperatures in Thornton ranged from a high of 67.0 degrees on the 19th down to a low of -5.5 degrees on the 6th.  Denver’s warmest temperature of 65 degrees also occurred on the 19th and it recorded its coldest of -10 degrees on the 5th.

All 31 days of the month saw low temperatures below freezing in Thornton and four days saw high temperatures fail to reach 32 degrees.  Two days saw readings below zero.  Denver’s readings were similar with four days staying below freezing and three seeing lows below zero.

Precipitation for the month was nearly double of the Denver historical average thanks to snowfall that was about double of normal.

Thornton recorded 1.06 inch of liquid precipitation, well above the average of 0.41 inch. Denver saw a bit less with 0.94 inch.

While no major snowstorms were seen, there were plenty of smaller events.  These gave Thornton 13.4 inches of the white stuff during the month, Denver saw 14.3 inches.  Both were about double the January average of 7.1 inches.  The official Denver measurement propelled January 2014 into the books as the 11th snowiest January on record.

Thornton, Colorado January 2014 temperature summary.
Thornton, Colorado January 2014 temperature summary.
Thornton, Colorado January 2014 precipitation summary.
Thornton, Colorado January 2014 precipitation summary.
CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
517 AM MST SAT FEB 1 2014

...................................

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF JANUARY 2014...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2014

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................
TEMPERATURE (F)
RECORD
 HIGH              76   01/27/1888
 LOW              -29   01/09/1875
HIGHEST            65   01/19        76     -11       66  01/24
LOWEST            -10   01/05       -29      19      -12  01/12
AVG. MAXIMUM     44.9              44.0     0.9     44.6
AVG. MINIMUM     17.3              17.4    -0.1     16.0
MEAN             31.1              30.7     0.4     30.3
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      4               5.5    -1.5        6
DAYS MIN <= 32     30              29.4     0.6       30
DAYS MIN <= 0       3               1.7     1.3        5 

PRECIPITATION (INCHES) 
RECORD 
 MAXIMUM         2.35   1883 
 MINIMUM         0.01   1933           
                        1934       
                        1952 
TOTALS           0.94              0.41    0.53     0.31 
DAILY AVG.       0.03              0.01    0.02     0.01 
DAYS >= .01         9               4.1     4.9        4
DAYS >= .10         3               0.9     2.1        1
DAYS >= .50         0               0.0     0.0        0
DAYS >= 1.00        0               0.0     0.0        0
GREATEST
 24 HR. TOTAL    0.26   01/30 TO 01/31           01/28 TO 01/29
                                                          01/29 TO 01/29
                                                          01/29 TO 01/29
 STORM TOTAL       MM                                 MM
 (MM/DD(HH))            MM                    01/29(00) TO 01/29(00)
                                                 01/29(00) TO 01/29(00)9
                                                 01/29(00) TO 01/29(00)9

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   MM
TOTALS           14.3               7.0

DEGREE_DAYS
HEATING TOTAL    1046              1063     -17     1067
 SINCE 7/1       3497              3531     -34     3300
COOLING TOTAL       0                 0       0        0
 SINCE 1/1          0                 0       0        0

FREEZE DATES
RECORD
 EARLIEST     09/08/1962
 LATEST       06/08/2007
EARLIEST                        10/07
LATEST                          05/05
..........................................................

WIND (MPH)
AVERAGE WIND SPEED              10.7
RESULTANT WIND SPEED/DIRECTION   4/230
HIGHEST WIND SPEED/DIRECTION    36/290    DATE  01/12
HIGHEST GUST SPEED/DIRECTION    44/280    DATE  01/12

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           10
NUMBER OF DAYS PC             14
NUMBER OF DAYS CLOUDY          7

AVERAGE RH (PERCENT)     56

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       0
LIGHT RAIN                0     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                2     SNOW                       5
LIGHT SNOW               11     SLEET                      0
FOG                      11     FOG W/VIS <= 1/4 MILE      4
HAZE                      4

-  INDICATES NEGATIVE NUMBERS.
R  INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T  INDICATES TRACE AMOUNT.

Thornton’s February weather preview: Month usually brings warmer temps, dry conditions

Thornton and Denver, Colorado February Weather Preview.February in Colorado typically brings to an end an extended period when average temperatures are at their lowest.  Winter begins to loosen its grip and temperatures get warmer but precipitation is not a particularly common event during the month.

Thanks to some late January snows, Denver’s seasonal snowfall has started to rebound but still remains below normal.  February is only our sixth snowiest month so it may not provide much help on the precipitation month.

Temperatures however do usually see a nice rebound during the month.  Average high temperatures climb from an average of 44 degrees at the start to 50 degrees by the end of February.

For the complete February preview including a look at historical averages and extremes as well as a look at what long range forecasts are predicting, click here.