As the sun sets on 2012 and the new year dawns, we look back on the past 12 months and can see it for what it was: unusually dry and warm.  While we were spared monster blizzards or much severe weather, there were still noteworthy weather events.

In terms of temperatures, Denver recorded an overall average of 53.8 degrees as recorded at Denver International Airport.  This was 3.4 degrees above average and put 2012 in the history books as the third warmest year in Denver history.  Here in Thornton we were, as usual, a bit cooler with an annual average temperature of 52.9 degrees.

The National Weather Service reported 73 days with temperatures at or above 90 degrees which far exceeds the average of 40 such days we normally see annually.  Here in Thornton we too saw more than average with 62 days of 90 degree or hotter temperatures.

The late spring and early summer proved to be record setting in terms of heat.  The month of June set a record high temperature average and July was the hottest month in Denver history.  Two days, June 25th and 26th broke daily high temperature records and tied Denver’s all-time high temperature of 105 degrees.

On the opposite end of the thermometer, Denver officially recorded 132 days with temperatures at or below freezing.  Here in Thornton we recorded two more with 134 days.  On average the Mile High City records 157 days of freezing temperatures.

While the year was unusually warm, it was also extraordinarily dry.  A mere 10.11 inches of precipitation was recorded in Denver’s rain bucket at DIA, 4.19 inches below normal.  Here in Thornton we were even drier as we recorded 9.61 inches of precipitation in 2012.  While extremely dry, neither measurement was low enough to make the list of top 15 driest years.

Total snowfall for the calendar year ended up at 38.5 inches at DIA and 35.1 inches in Thornton. Both locations fell well short of the Denver annual average snowfall of 53.5 inches.  Denver’s snowfall was enough to keep it off the list of top 15 least snowiest years.  However Thornton’s measurement would have made it the 13th least snowiest on Denver’s list.

Snowfall started out reasonably strong thanks to a healthy snowfall total in February.  However while March is on average our snowiest month, that did not hold true in 2012.  A mere 0.03 inch of precipitation was recorded setting the stage for the balance of a dry year.

Combined, June, July and August recorded only 1.81 inches of precipitation at DIA.  This was an astonishing 4.02 inches below average for that period.  Thornton fared only slightly better over the period with 2.34 inches.

While September brought above normal precipitation, the final three months of 2012 returned us to drier than normal conditions.

Extreme weather events were not particularly common in 2012.  There was a distinct lack of heavy snow events and even spring’s severe weather season was relatively tame.

However, the hot summer temperatures and tinder dry conditions did lead to a deadly and destructive wildfire season.

The High Park Fire in June quickly became the second largest wildfire in Colorado history.  That blaze was soon followed by the Waldo Canyon Fire west of Colorado Springs which went into the history books as the most destructive blaze in state history.

Click here for Thornton’s 2012 Climate Summary Report

From the National Weather Service:

CLIMATE REPORT
NATIONAL WEATHER SERVICE BOULDER, CO
130 AM MST TUE JAN 1 2013

...THE DENVER CO CLIMATE SUMMARY FOR THE YEAR OF 2012...

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2012

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................ 
TEMPERATURE (F)
RECORD
 HIGH             105   06/26/2012
                        06/25/2012
                        07/20/2005
 LOW              -29   01/09/1875
HIGHEST           105R  06/26        64      41       99  08/25
                        06/25                             07/31
                                                          07/04
LOWEST             -6   01/11        36     -42      -17  02/02
AVG. MAXIMUM     68.4              64.7     3.7     64.8
AVG. MINIMUM     39.3              36.3     3.0     36.4
MEAN             53.9              50.5     3.4     50.6
DAYS MAX >= 90     73              39.6    33.4       50
DAYS MAX <= 32     19              20.0    -1.0       23
DAYS MIN <= 32    132             156.9   -24.9      158
DAYS MIN <= 0       4               5.8    -1.8       12

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        23.31   1196
 MINIMUM         7.29   2008
TOTALS          10.11             14.30   -4.19    17.31
DAILY AVG.       0.03              0.04   -0.01     0.05
DAYS >= .01        52              79.7   -27.7       80
DAYS >= .10        23              34.9   -11.9       37
DAYS >= .50         9               7.6     1.4       10
DAYS >= 1.00        1               2.3    -1.3        6
GREATEST
 24 HR. TOTAL    1.63   MM                       05/11 TO 05/12
                                                          10/26 TO 10/26
                                                          10/26 TO 10/26
 STORM TOTAL       MM                               2.52
 (MM/DD(HH))            MM                    05/12(00) TO 05/12(00)
                                                 10/26(00) TO 10/26(00)6
                                                 10/26(00) TO 10/26(00)6

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   5
 24 HR TOTAL       MM
 SNOW DEPTH        MM   MM
TOTALS           38.5              53.8   -15.3     46.8
 LIQUID EQUIV    3.85              5.40   -1.55     4.68
SINCE 7/1        12.4              22.5   -10.1     29.5
 LIQUID 7/1      1.24              2.20   -0.96     2.95
SNOWDEPTH AVG.      0                MM      MM        0
DAYS >= TRACE      36              33.3     2.7       41
DAYS >= 1.0        13              16.3    -3.3       16
GREATEST
 SNOW DEPTH        11   02/04                          7  01/10
                                                          01/11
 24 HR TOTAL     12.5   MM                       10/26 TO 10/26
                                                          10/26 TO 10/26
                                                          10/26 TO 10/26
 STORM TOTAL       MM                                8.5
 (MM/DD(HH))            MM                    10/26(00) TO 10/26(00)
                                                 10/26(00) TO 10/26(00)6
                                                 10/26(00) TO 10/26(00)6

DEGREE_DAYS
HEATING TOTAL    5198              6059    -861     6069
 SINCE 7/1         MM              2468      MM       MM
COOLING TOTAL    1236                 0    1236      964
 SINCE 1/1       1236               769     467      964

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

WIND (MPH)
AVERAGE WIND SPEED              10.3
RESULTANT WIND SPEED/DIRECTION   3/205
HIGHEST WIND SPEED/DIRECTION    52/240    DATE  06/02
HIGHEST GUST SPEED/DIRECTION    67/250    DATE  06/02

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           86
NUMBER OF DAYS PC            235
NUMBER OF DAYS CLOUDY         45

AVERAGE RH (PERCENT)     44

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                4     RAIN                      12
LIGHT RAIN               45     FREEZING RAIN              0
LT FREEZING RAIN          1     HAIL                       3
HEAVY SNOW                4     SNOW                      15
LIGHT SNOW               37     SLEET                      0
FOG                      73     FOG W/VIS <= 1/4 MILE     21
HAZE                     51

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