With 2011 now behind us we can look back at the year in weather and in doing so we note that it wasn’t a particularly eventful one. Temperatures were very close to average for the year and while it was a wet one, there weren’t any events that will remain emblazoned in our memories.
In terms of temperatures, the year saw an average temperature of 50.6 degrees as recorded at Denver’s official monitoring station at Denver International Airport. This was a negligible 0.1 degrees above normal. Thornton was slightly cooler with an average of 49.8 degrees.
Denver recorded 50 days of 90 degree or warmer temperatures but failed to reach the 100 degree mark at all. Three days including July 4th, July 31st and August 25th hit 99 degrees. Thornton saw 44 90 degree or warmer days during the year and only one hit 99 degrees (July 4th).
The mercury dipped below zero on 12 days at DIA with the coldest temperature of -17 degrees occurring on February 2nd. Here in Thornton we recorded 10 days below zero with the coldest reading coming on February 2nd when we dropped to -14.7 degrees.
While temperatures were not particularly notable, we did managed to record much more precipitation than normal. In all, DIA saw 17.31 inches which was 2.39 inches above the normal of 14.92. Thornton bested Denver’s number with 18.80 inches during the year.
The first quarter of the year saw precipitation readings slightly below normal. Then in May, the skies opened up and Denver received 4.79 inches of rain – far above the normal for the month of 2.15 inches. Most of this fell with two storms systems, one on the 11th and 12th and a second on the 17th and 18th.
Thornton as well saw a wet May as 5.67 inches fell into our rain bucket. Much of that occurred in the 24 hours leading up to the city’s annual ThorntonFest resulting in flooding at the Multipurpose Fields and forcing the cancellation of the festival.
June and July brought more wet weather and above normal precipitation. The monsoons during the first half of July brought rain on 9 out of 10 days from the 5th to the 14th and the month recorded 3.20 inches overall.
Here again Thornton was the recipient of even more rain as we recorded 5.51 inches during the month. One nighttime storm did provide not only rain but a decent lightning show and another resulted in flooding in the southern part of the city.
The last half of July and all of August were quite dry and followed by a relatively average September. October once again brought above normal precipitation, November followed with drier than normal conditions and December was wetter than average.
For the calendar year, Denver received 47.5 inches of snowfall. The biggest storm occurred on October 26th when 8.0 inches of snow fell. Thornton was slightly snowier as we received 51.0 inches of snow during 2011.
Click here to view Thornton’s 2011 climate summary. Following is the official Denver statistics for the year from the National Weather Service.
CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
217 PM MST SUN JAN 1 2012
...................................
...THE DENVER CO CLIMATE SUMMARY FOR THE YEAR OF 2011...
CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2011
WEATHER OBSERVED NORMAL DEPART LAST YEAR`S
VALUE DATE(S) VALUE FROM VALUE DATE(S)
NORMAL
................................................................
TEMPERATURE (F)
RECORD
HIGH 105 07/20/2005
08/08/1878
LOW -29 01/09/1875
HIGHEST 99 08/25 64 35 102 07/17
07/31
07/04
LOWEST -17 02/02 36 -53 -16 01/07
AVG. MAXIMUM 64.8 64.7 0.1 65.3
AVG. MINIMUM 36.4 36.3 0.1 37.0
MEAN 50.6 50.5 0.1 51.2
DAYS MAX >= 90 50 39.6 10.4 49
DAYS MAX = .01 80 79.7 0.3 71
DAYS >= .10 37 34.9 2.1 24
DAYS >= .50 10 7.6 2.4 9
DAYS >= 1.00 6 2.3 3.7 3
GREATEST
24 HR. TOTAL 1.95 MM 12/31 TO 12/31
12/31 TO 12/31
12/31 TO 12/31
STORM TOTAL MM MM
(MM/DD(HH)) MM 12/31(00) TO 12/31(00)
12/31(00) TO 12/31(00)1
12/31(00) TO 12/31(00)1
SNOWFALL (INCHES)
RECORDS
TOTAL MM 5
24 HR TOTAL MM
SNOW DEPTH MM MM
TOTALS 47.5 MM MM 27.8
LIQUID EQUIV MM MM MM MM
SINCE 7/1 29.5 MM MM 4.8
LIQUID 7/1 MM MM MM MM
SNOWDEPTH AVG. 0 MM MM 0
DAYS >= TRACE 40 MM MM 42
DAYS >= 1.0 16 MM MM 10
GREATEST
SNOW DEPTH 7 01/11 8 03/24
01/10
24 HR TOTAL 8.0 11/26 12/31 TO 12/31
12/31 TO 12/31
12/31 TO 12/31
STORM TOTAL MM MM
(MM/DD(HH)) MM 12/31(00) TO 12/31(00)
12/31(00) TO 12/31(00)1
12/31(00) TO 12/31(00)1
DEGREE_DAYS
HEATING TOTAL 6069 6059 10 5774
SINCE 7/1 MM 2463 MM 2072
COOLING TOTAL 964 769 195 870
SINCE 1/1 964 769 195 870
FREEZE DATES
RECORD
EARLIEST 09/08/1962
LATEST 06/08/2007
EARLIEST 10/07
LATEST 05/05
..................................................
WIND (MPH)
AVERAGE WIND SPEED 9.9
RESULTANT WIND SPEED/DIRECTION 2/211
HIGHEST WIND SPEED/DIRECTION 51/210 DATE 07/13
HIGHEST GUST SPEED/DIRECTION 72/200 DATE 06/29
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.50
NUMBER OF DAYS FAIR 87
NUMBER OF DAYS PC 232
NUMBER OF DAYS CLOUDY 46
AVERAGE RH (PERCENT) 49
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 51 MIXED PRECIP 0
HEAVY RAIN 11 RAIN 22
LIGHT RAIN 76 FREEZING RAIN 1
LT FREEZING RAIN 3 HAIL 8
HEAVY SNOW 7 SNOW 21
LIGHT SNOW 39 SLEET 0
FOG 92 FOG W/VIS