Category Archives: Climatology

2016 Thornton annual weather recap: A warmer, drier than normal year

Another year in the books for us and as we look back on our overall weather for 2016, we see overall temperatures were warmer than normal while precipitation fell a good bit short of normal.  The year did seem to lack any major drama in terms of severe weather or winter storms which is likely a good thing.

We started out with above normal temperatures for the first quarter of the year.  March, as usual, was our snowiest month and also became our wettest month of the year.  April followed with some snow and a good bit of rain to be our second wettest and May the third.

May also saw much cooler than normal temperatures with the biggest departure from normal. From there, drier conditions reigned through November with each month registering below normal precipitation.

October and November saw our biggest deviations from normal temperatures as high pressure dominated and we saw extraordinarily warm conditions.  This changed in December as Arctic air infiltrated the region leading to well below normal temperatures.

Overall, Thornton’s annual temperature came in at 51.6 degrees.  This was 1.1 degrees above Denver’s 30 year average (1981 to 2010) of 50.5 degrees.  We saw readings ranging from a high of 100.4 degrees down to a low of 10.7 degrees below zero.  Fifty days saw 90 degrees or higher while at the opposite end we saw 169 days with readings at or below freezing.

Out at DIA where the Mile High City’s official measurements are kept, it was warmer with an annual average of 52.3 degrees.  For Denver, that ranks as the 14th warmest year in its 145 year temperature history.

In terms of precipitation, Denver averages 14.3 inches per calendar year.  Both Thornton and Denver fell well short of that mark with 12.98 inches and 11.85 inches respectively.  For Denver, that is the 37th driest year on record.

Thornton saw a very respectable 68.1 inches for the calendar year.  At the airport Denver saw less with 61.6 inches. Both were well above the annual average of 53.8 inches.

Click here to view Thornton’s 2016 climate summary report.

Thornton, Colorado's annual temperature summary for 2016.
Thornton, Colorado’s annual temperature summary for 2016.
Thornton, Colorado's annual precipitation summary.
Thornton, Colorado’s annual precipitation summary.

From the National Weather Service:

CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
1010 AM MST SUN JAN 1 2017

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

...THE DENVER CO CLIMATE SUMMARY FOR THE YEAR OF 2016... 

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2016

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 08/08/1878
 LOW              -29   01/09/1875
HIGHEST           102   07/10/2016                   98  08/15
LOWEST            -15   12/17/2016                  -10  01/04
AVG. MAXIMUM     66.7              64.7     2.0     65.4
AVG. MINIMUM     38.0              36.3     1.7     38.6
MEAN             52.3              50.5     1.8     52.0
DAYS MAX >= 90     55              39.6    15.4       48
DAYS MAX <= 32     14              20.0    -6.0       29
DAYS MIN <= 32    138             156.9   -18.9      126
DAYS MIN <= 0 4 5.8 -1.8 7 PRECIPITATION (INCHES) RECORD MAXIMUM 23.31 1967 MINIMUM 7.29 2008 TOTALS 11.85 14.30 -2.45 18.31 DAILY AVG. 0.03 0.03 0.00 0.05 DAYS >= .01        71              79.7    -8.7      107
DAYS >= .10        32              34.9    -2.9       49
DAYS >= .50         5               7.6    -2.6       10
DAYS >= 1.00        2               2.3    -0.3        2
GREATEST
 24 HR. TOTAL    1.38   2016                5/26 TO 5/27
                 1.22   2016                4/15 TO 4/16
                 0.77   2016                3/23 TO 3/23
SNOWFALL RECORDS JANUARY THROUGH DECEMBER TOTALS
               MAXIMUM           MINIMUM
                115.9   1913       18.9    1887
                112.0   1959       21.5    1888
                 99.2   1929       21.8    1890
 24 HR TOTAL     23.6   12/24/1982 TO 12/24/1982

TOTALS           61.6              53.8     7.8     64.4
 LIQUID EQUIV    6.16              5.40    0.76     6.44
SINCE 7/1        11.4              22.5   -11.1     22.6
 LIQUID 7/1      1.14              2.20   -1.06     2.26
SNOWDEPTH AVG.      0                MM      MM        0
DAYS >= TRACE      37              33.3     3.7       51
DAYS >= 1.0        13              16.3    -3.3       25
GREATEST
 SNOW DEPTH        10   03/24                          9  02/23
 24 HR TOTAL     13.1   03/23
                 11.8   04/16
                  6.9   02/01

 STORM TOTAL     13.1   03/23

DEGREE_DAYS
HEATING TOTAL    5415              6059    -644     5479
 SINCE 7/1       2042              2468    -426     5575
COOLING TOTAL     878               769     109      877
 SINCE 1/1        878               769     109      877

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

WIND (MPH)
AVERAGE WIND SPEED              10.0
RESULTANT WIND SPEED/DIRECTION   2/194
HIGHEST WIND SPEED/DIRECTION    54/340    DATE  07/24
HIGHEST GUST SPEED/DIRECTION    74/340    DATE  07/24

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           94
NUMBER OF DAYS PC            210
NUMBER OF DAYS CLOUDY         62

AVERAGE RH (PERCENT)     50

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                3     RAIN                      13
LIGHT RAIN               72     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       4
HEAVY SNOW                5     SNOW                      17
LIGHT SNOW               39     SLEET                      0
FOG                      80     FOG W/VIS <= 1/4 MILE     26
HAZE                     33

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

..........2016 CLIMATE YEAR IN REVIEW........... 

THE YEAR OF 2016 IN DENVER, THE FRONT RANGE AND NORTHERN COLORADO,
WAS A TRANSITION FROM STRONG EL NINO CONDITIONS OVER TO WEAK LA NINA
AND INTO THE CURRENT ENVIRONMENT WHICH IS ENSO NEUTRAL. AS EL NINO
CONDITIONS WEAKENED FROM MID-WINTER THROUGH LATE SPRING 2016,
TEMPERATURES CAME IN WARMER THAN AVERAGE FOR JANUARY THROUGH MARCH
ALONG WITH NEAR TO SLIGHTLY ABOVE NORMAL PRECIPITATION FOR THE THREE
MONTHS. DENVER`S WETTEST MONTH OF 2016 ARRIVED IN APRIL WITH 2.56
INCHES OF PRECIPITATION ALONG WITH 18.4 INCHES OF SNOW. TEMPERATURES
FOR THEN COOLED TO NEAR AVERAGE FOR APRIL AHEAD OF ABOVE AVERAGE
PRECIPITATION AND FURTHER COOLING INTO MAY. MAY WAS THE SECOND
WETTEST MONTH OF 2016 AND ALSO HAD THE COLDEST MONTHLY DEPARTURE
FROM AVERAGE FOR THE YEAR AT 2.7 DEGREES BELOW DENVER`S MONTHLY MAY
NORMAL.

WITH WATER TEMPERATURE CONDITIONS RAPIDLY CHANGING IN THE EQUATORIAL
PACIFIC REGION IN THE FIRST HALF OF 2016, NORTHERN COLORADO AND THE
HIGH PLAINS STATES TRANSITIONED INTO A DIFFERENT PATTERN AS WELL.
THE FIVE MONTHS OF JUNE THROUGH OCTOBER ALL REGISTERED PRECIPITATION
TOTALS BELOW THEIR MONTHLY AVERAGE. AUGUST RECEIVED A MERE 0.22
INCHES OF PRECIPITATION IN DENVER WHICH WAS 1.47 INCHES BELOW
AVERAGE AND WAS THE LOWEST PERCENTAGE OF NORMAL OF ALL MONTHS OF
2016 AT 13 PERCENT.

AS A LARGE AND STRONG RIDGE OF HIGH PRESSURE PERSISTED ACROSS THE
CENTRAL AND SOUTHERN ROCKIES FROM MID SUMMER INTO MID FALL,
TEMPERATURES REFLECTED THIS WITH OCTOBER AND NOVEMBER LANDING WELL
ABOVE THEIR MONTHLY AVERAGE TEMPERATURES. BOTH OCTOBER AND NOVEMBER
IN DENVER CAME IN WITH MONTHLY TEMPERATURE DEPARTURES OF 6.9 AND 6.8
DEGREES ABOVE AVERAGE RESPECTIVELY. PRECIPITATION ALSO HELD BELOW
NORMAL FOR THESE TWO MONTHS AS WELL WITH 0.26 INCHES IN OCTOBER AND
0.52 INCHES IN NOVEMBER. HOWEVER, WITH TWO MOIST AND WINTER-LIKE
PACIFIC DISTURBANCES IN MID NOVEMBER, THE DEPARTURE FROM NORMAL IN
NOVEMBER WAS ONLY -0.09 OR 85 PERCENT OF AVERAGE.

AS METEOROLOGISTS OBSERVED THE DEVELOPING NORTHERN HEMISPHERIC
PATTERN FROM LATE NOVEMBER INTO EARLY DECEMBER, IT WAS CLEAR THAT A
CHANGE FOR THE COLDER WAS COMING TO MUCH OF THE UNITED STATES,
INCLUDING DENVER. IN EARLY DECEMBER, WINDS ALOFT BROADLY EXTENDED
LONGITUDINALLY FROM THE ARCTIC REGION NORTH OF SIBERIA, ACROSS THE
NORTH POLE REGION AND INTO SOUTHERN CANADA. FRIGID ARCTIC AIR WAS
BROUGHT SOUTHWARD INTO CANADA AND ACROSS MUCH OF THE CENTRAL UNITED
STATES AS A RESULT. THIS WAS FOLLOWED BY ANOTHER PATTERN OF
PERSISTENT NORTHERLY WINDS ALOFT ACROSS NORTHERN LATITUDES WHICH
USHERED IN ANOTHER PERIOD OF COLD AND SNOWFALL AHEAD OF THE
CHRISTMAS HOLIDAY. THESE TWO SYSTEMS WERE ENOUGH TO BRING DECEMBER`S
AVERAGE MONTHLY TEMPERATURE DOWN TO -2.2 BELOW NORMAL ALONG WITH
ABOVE AVERAGE PRECIPITATION AND SNOWFALL.

WHEN 2016 ENDED, THE AVERAGE ANNUAL TEMPERATURE FOR DENVER FINALIZED
AT 52.3 DEGREES, WHICH IS 1.8 DEGREES ABOVE THE 1981-2010 ANNUAL
AVERAGE OF 50.5 DEGREES. THIS RANKS AS 14TH WARMEST IN DENVER`S 145
YEAR TEMPERATURE HISTORY. THE WARMEST YEAR IN DENVER`S WEATHER
HISTORY WAS IN 1934 WITH AN AVERAGE ANNUAL TEMPERATURE OF 54.8
DEGREES. THE COLDEST YEAR WAS 1912 WITH AN ANNUAL AVERAGE OF 47.6
DEGREES.

FOR THE PRECIPITATION CATEGORY, 2016 IN DENVER WAS ON THE DRY SIDE
OF THE 1981-2010 ANNUAL AVERAGE. THE YEAR ENDED WITH 11.85 INCHES OF
PRECIPITATION WHICH WAS 2.45 INCHES BELOW THE ANNUAL NORMAL OF 14.30
INCHES, OR 83 PERCENT OF NORMAL. THE ANNUAL TOTAL OF 11.85 INCHES
RANKS AS 37TH DRIEST IN DENVER`S 145 YEAR WEATHER HISTORY. THE
WETTEST YEAR IN DENVER`S WEATHER HISTORY WAS IN 1967 WHEN 23.31
INCHES OF PRECIPITATION FELL. DENVER`S DRIEST YEAR OCCURRED IN 2002
WHEN ONLY 7.48 INCHES OF PRECIPITATION WAS RECORDED.

December 2016 weather recap: A colder, wetter month finally arrives

For the three previous months we had seen warmer and drier than normal conditions.  December finally brought an end to that streak with temperatures well below normal and precipitation almost doubt the average for the month.

The month was largely an unsettled one as a series of storm systems moved across the region.  Two significant blasts of Arctic air sent the mercury plummeting.  The first, from the 6th to the 8th, brought little snowfall but the second from the 16th to the 18th was quite generous.  The balance of the month saw things warm up with 10 of the last 13 days seeing above normal mercury readings.

Overall, Thornton saw an average monthly temperature of 28.1 degrees.  This was well below Denver’s 30 year average (1981 – 2000) for the month of December of 30.0 degrees.  Out at DIA where the Mile High City’s official measurements are taken, the month averaged 27.8 degrees.

Temperatures ranged from a high of 65.7 degrees on the 30th down to a bone-chilling low of 10.7 degrees below zero on the morning of the 17th.  Denver saw its warmest temperature of 65 degrees and coldest of 15 degrees below zero on the same dates.

That low reading in Denver on the 17th was also a record low for the date.  Additionally, the airport saw a high temperature of only 3 degrees that day setting a new record low maximum for the 17th.

In all, Thornton saw five days where the high temperatures failed to climb above freezing and four days with temperatures below zero.  Denver recorded six and four respectively.

In terms of precipitation, Denver averages 0.35 inches of liquid precipitation during December.  Thornton easily bested the average with 0.64 inches for the month while Denver fared better with 0.78 inches.

Both Thornton and Denver saw above average levels of snowfall.  The Mile High City averages 8.5 inches in December. In 2016, Thornton saw 8.9 inches while DIA recorded 9.7 inches.

Click here to view Thornton’s December  2016 climate report.

Thornton, Colorado's December 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado’s December 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado's December 2016 precipitation summary. (ThorntonWeather.com)
Thornton, Colorado’s December 2016 precipitation summary. (ThorntonWeather.com)

From the National Weather Service:

CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
718 AM MST SUN JAN 1 2017

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

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2016... 

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2016

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................ 
TEMPERATURE (F)
RECORD
 HIGH              79   12/05/1939
 LOW              -25   12/22/1990
                        12/24/1876
HIGHEST            65   12/30        43      22       69  12/09
LOWEST            -15   12/17        17     -28        0  12/28
                                                          12/17
AVG. MAXIMUM     42.7              42.8    -0.1     40.9
AVG. MINIMUM     12.9              17.1    -4.2     17.9
MEAN             27.8              30.0    -2.2     29.4
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      6               5.8     0.2       10
DAYS MIN <= 32     30              29.4     0.6       28
DAYS MIN <= 0 4 2.0 2.0 2 PRECIPITATION (INCHES) RECORD MAXIMUM 5.21 1913 MINIMUM 0.00 1881 TOTALS 0.78 0.35 0.43 0.71 DAILY AVG. 0.03 0.01 0.02 0.02 DAYS >= .01         6               4.1     1.9        5
DAYS >= .10         2               1.1     0.9        3
DAYS >= .50         0               0.1    -0.1        0
DAYS >= 1.00        0               0.0     0.0        0
GREATEST
 24 HR. TOTAL    0.63   12/16 TO 12/17

SNOWFALL (INCHES)
TOTALS            9.7   2016        8.5 NORMAL
RECORDS          57.4   1913
                    T   1905 1906 2002

DEGREE_DAYS
HEATING TOTAL    1146              1086      60     1097
 SINCE 7/1       2042              2468    -426     2187
COOLING TOTAL       0                 0       0        0
 SINCE 1/1        878               769     109      877

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

WIND (MPH)
AVERAGE WIND SPEED              9.2
RESULTANT WIND SPEED/DIRECTION   3/167
HIGHEST WIND SPEED/DIRECTION    37/260    DATE  12/05
HIGHEST GUST SPEED/DIRECTION    46/260    DATE  12/05

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR            7
NUMBER OF DAYS PC             18
NUMBER OF DAYS CLOUDY          6

AVERAGE RH (PERCENT)     57

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       0
LIGHT RAIN                1     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                2     SNOW                       3
LIGHT SNOW                7     SLEET                      0
FOG                      11     FOG W/VIS <= 1/4 MILE      3
HAZE                      6

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

Thornton’s January 2017 preview: Usually a relatively cold, dry month

Denver's January weather and climatology preview for 2013.As we begin the new year the winter chill begins to set in.  While January can see its share of extremes, the month historically sees stable temperatures and is usually relatively dry.

January ranks as the second coldest month in Denver next to December with average temperatures remaining virtually the same from the start to the end of the month.

In terms of snowfall, the month only ranks as the fourth snowiest and it is not uncommon for it to be quite dry.

What does January 2017 hold for us?  Follow the link to find out.

For the complete January preview including a look at historical averages and extremes, click here. 

Astronomical winter to begin Wednesday with the shortest day of the year

The Earth at the Winter Solstice. The Northern Hemisphere sees their shortest day of the year while the Southern Hemisphere gets its longest. (NASA)
The Earth at the Winter Solstice. The Northern Hemisphere sees their shortest day of the year while the Southern Hemisphere gets its longest. (NASA)

Astronomical winter arrives in Thornton early tomorrow morning and with the solstice also comes the shortest day of the year.

Winter officially begins at 3:44am on Wednesday, December 21, 2016. The Winter Solstice occurs when the North Pole is tilted at its furthest from the sun – 23.5 degrees away. This results in the shortest day of the year in the Northern Hemisphere.

Here in Denver, with sunrise at 7:18am and sunset at 4:39pm, our day Wednesday is 9 hours, 21 minutes and 14 seconds long. The day after it will be three seconds longer and each day from now through to the Summer Solstice in June will get gradually longer as well.

While we have a short day on the winter solstice, it is nothing like what will be experienced in the Arctic Circle.  Areas north of there to the North Pole will have no direct sunlight at all.  Conversely, areas south of the Antarctic Circle toward the South Pole will have 24 hours of daylight and have a midnight sun.

Did you know that there is a difference between the astronomical seasons that we are discussing here and meteorological seasons?

Meteorological seasons differ slightly and are geared toward matching the calendar with the annual temperature cycle. This is done primarily for meteorological observing and forecasting and in many ways it is more logical than the astronomical seasons.

For the Northern Hemisphere, the meteorological spring covers the months of March, April and May. Summer brings the hottest months of the year and so meteorological summer is June, July and August. Meteorological fall then is September, October and November followed by the coldest months of December, January and February as meteorological winter.

Thornton’s December preview: With arrival of winter, cold and snow increase

The month of December brings with it the official start of winter and oftentimes, colder and snowier weather conditions. It however can also offer unseasonably warm temperatures and bone dry conditions.  Given our recent mild and dry weather, we are certainly hoping for a change in the coming month.

Overall December’s monthly mean temperature of 30.0 degrees (1981 – 2010 averages) makes it our coldest month.  Snow is always on everyone’s mind this time of year but December is only our 3rd snowiest month behind March and November with an average of 8.5 inches of the white stuff.

We closed out November quite wet and chilly and that is expected to continue into the first part of December.  Long term models then point to a continuation of above normal precipitation but near normal temperatures.

Get all the details on Thornton’s December weather including a look back at historical events and a look at the long range forecast in our December weather preview here.

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Denver ties all-time record high temperature for month of November

Record High TemperaturesWe thought the daily high temperature record for November 16 would fall today and indeed it did.  However the Mile High City also managed to tie the record for the warmest temperature ever recorded during the month of November.

At 1:24pm the station at Denver International Airport reported a mercury reading of 80 degrees.

This easily bested the previous record high temperature for November 16 of 77 degrees set in 1941.

Perhaps more notably, the reading also ties the all-time record high temperature for the month of November.  The old mark was 80 degrees set on November 8, 2006.  This is in turn the latest in the year an 80 degree reading has been tallied.

Here in Thornton, we were a bit warmer than DIA.  Our temperature topped out at 81.5 degrees at 1:02pm.

Showcasing the wide swings of weather we experience here in Colorado is the fact that after these records today, high temperatures tomorrow won’t go very far into the 40s.  Check out forecast for the latest.

  • Stay up to date with Thornton’s weather: ‘Like’ us on Facebook, follow us on Twitter and add us to your Google+ circles

2016 ‘Likely’ Hottest Year Ever: WMO

2016 will “very likely” be the hottest year on record, according to the United Nations World Meteorological Organization. According to a news release from the WMO, 2016 will likely eclipse the previous hottest year, 2015. “Another year. Another record. The high temperatures we saw in 2015 are set to be beaten in 2016,” said WMO Secretary-General… Continue reading 2016 ‘Likely’ Hottest Year Ever: WMO

Thornton’s November 2016 preview: Will we break out of the warm, dry pattern?

Thornton's November weather previewThe weather during the month of November in Denver metro area can offer just about anything.  While it is normally a quiet month, it can be prone to extremes.

November is Denver’s second snowiest month and major snowstorms are not entirely uncommon.  However conditions can also be quite dry.

Temperatures during the month continue to cool as we get closer to winter and by the end of the month the low temperatures routinely dip to 20 degrees or below.  At times it can in fact bring conditions more like what we see in January.

Certainly given how warm and dry we were in October, we could use some relief.  Will that happen?

Get all the details on November’s weather and what we can expect in our complete preview here.

October 2016 weather recap: An exceedingly warm and dry month

High pressure was the dominant weather feature for the month of October and that led to a pattern that blocked off moisture and kept temperatures well above normal.  Record-setting highs were made while precipitation was a rare event.

The historical average monthly temperature for the month of October in Denver is 50.9 degrees.  That number was easily eclipsed.  Here in Thornton we saw an average temperature of 55.8 degrees.  Out at DIA where Denver’s official numbers are kept, it was much warmer with an average of 57.8 degrees.

Both averages for October 2016 were far above normal.  Officially the month was so warm it became the fourth warmest October on record in Denver.  The number one spot was quite secure though with an average of 59.9 degrees back in 1950.

Temperatures in Thornton ranged from a high of 84.8 degrees on the 16th down to a low of 27.1 degrees on the morning of the 20th.  Out at the airport, the warmest reading was 86 degrees and the lowest 25 degrees, both on the same days that Thornton saw its warmest and coldest readings.

Denver recorded four record daily high temperatures during the month.  The first record high came on the 15th of the month to be followed by records on the 27th and 28th then a tie for the record high on the 31st.

In terms of precipitation, the same high pressure that kept things warm, kept things dry as well.  Thornton recorded a mere 0.43 inches in its rain bucket, all during the first half of the month. The airport was a bit drier with 0.26 inches recorded.

On average Denver receives 1.02 inches of precipitation in October so both locations were far below normal.  While it was certainly dry, it was not so much so that it was a record-setter as the month failed to make it into the top 20 driest Octobers.

No snow was recorded during the month so we are still awaiting that first event of the season.  This however is not entirely unusual as historically, 27% of Denver’s October fail to see any of the white stuff.

Click here to view Thornton’s October 2016 climate report.

Thornton, Colorado's October 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado’s October 2016 temperature summary. (ThorntonWeather.com)
Thornton, Colorado's October 2016 precipitation summary. (ThorntonWeather.com)
Thornton, Colorado’s October 2016 precipitation summary. (ThorntonWeather.com)

From the National Weather Service:

CLIMATE REPORT
NATIONAL WEATHER SERVICE DENVER/BOULDER CO
244 AM MDT TUE NOV 1 2016

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

...THE DENVER CO CLIMATE SUMMARY FOR THE MONTH OF OCTOBER 2016... 

CLIMATE NORMAL PERIOD 1981 TO 2010
CLIMATE RECORD PERIOD 1872 TO 2016

WEATHER         OBSERVED          NORMAL  DEPART  LAST YEAR`S
                 VALUE   DATE(S)  VALUE   FROM    VALUE  DATE(S)
                                          NORMAL
................................................................ 
TEMPERATURE (F)
RECORD
 HIGH              89   10/16/1991
                        10/10/1910
 LOW               -2   10/29/1917
HIGHEST            86   10/16        83       3       87  10/11
LOWEST             25   10/20        22       3       28  10/28
AVG. MAXIMUM     74.5              65.3     9.2     70.1
AVG. MINIMUM     41.2              36.6     4.6     42.8
MEAN             57.8              50.9     6.9     56.5
DAYS MAX >= 90      0               0.0     0.0        0
DAYS MAX <= 32      0               0.4    -0.4        0
DAYS MIN <= 32      3               8.5    -5.5        1
DAYS MIN <= 0       0               0.0     0.0        0

PRECIPITATION (INCHES)
RECORD
 MAXIMUM         4.17   1969
 MINIMUM            T   1934
TOTALS           0.26              1.02   -0.76     1.76
DAILY AVG.       0.01              0.03   -0.02     0.06
DAYS >= .01         3               5.3    -2.3        6
DAYS >= .10         1               2.4    -1.4        3
DAYS >= .50         0               0.5    -0.5        2
DAYS >= 1.00        0               0.1    -0.1        0
GREATEST
 24 HR. TOTAL    0.22   10/05 TO 10/06           10/20 TO 10/21

SNOWFALL (INCHES)
RECORDS
 TOTAL             MM   MM
TOTALS            0.0               4.0

DEGREE_DAYS
HEATING TOTAL     231               440    -209      274
 SINCE 7/1        310               581    -271      301
COOLING TOTAL      17                 5      12       16
 SINCE 1/1        878               769     109      877

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

WIND (MPH)
AVERAGE WIND SPEED              10.0
RESULTANT WIND SPEED/DIRECTION   4/197
HIGHEST WIND SPEED/DIRECTION    33/260    DATE  10/04
HIGHEST GUST SPEED/DIRECTION    42/270    DATE  10/03

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.50
NUMBER OF DAYS FAIR           10
NUMBER OF DAYS PC             17
NUMBER OF DAYS CLOUDY          4

AVERAGE RH (PERCENT)     40

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

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

No October snow in Denver? Not unusual at all

The lack of measurable snow this October is not all that unusual. Click for larger view.
The lack of measurable snow this October is not all that unusual. Click for larger view.

October will end with Denver not having seen any snow accumulation at all during the month.  While that, coupled with the overall lack of precipitation is concerning, not having snow is not at all unusual.

On average, the Mile High City receives 4.2 inches during October.

However, since record-keeping began in 1882, the month failed to yield any snow at all in 19 years since.  Further, in another 17 of those years we only received a trace.

This means that in 27% of the past 134 years, we saw essentially no accumulating snow in October.  So, the fact we won’t have received any this month is not uncommon.

The average date for our first snowfall is October 18th so we aren’t running all that far behind.  The earliest seasonal snowfall came on September 3, 1961 and the latest on November 21, 1934.

We have been exceedingly dry, really since the first part of June.

In October, Denver has recorded a mere 0.26 inches of precipitation while here in Thornton we have fared better with 0.43 inches.  On average we expect to see 0.97 inches so both locations are well below normal.

Perhaps more notable than the lack of moisture is the temperatures which have been unseasonably warm.

As of right now, the average temperature for the month is at 57.2 degrees in Denver, 55.1 degrees in Thornton.  This is running far above the historical October average temperature of 50.9 degrees.

Depending on temperatures between now and the end of the month, it is looking likely that October 2016 will finish somewhere in the top five or six warmest Octobers on record.