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000
CXUS55 KRIW 011718
CLMCPR

CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1018 AM MST SAT JAN 01 2022

...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR CASPER FOR THE MONTH OF
DECEMBER 2021...

...OFFICIAL CLIMATE DATA FOR THE MONTH OF DECEMBER 2021 WILL BE
AVAILABLE IN APPROXIMATELY 60 DAYS FROM THE NATIONAL CENTERS FOR
ENVIRONMENTAL INFORMATION (HTTP://WWW.NCDC.NOAA.GOV/CDO-
WEB/DATASETS). UNOFFICIAL ASOS DAILY SUMMARIES ARE AVAILABLE ON THE
INTERNET AT HTTP://WWW.WEATHER.GOV/CLIMATE/INDEX.PHP?WFO=RIW

...CASPER WAS WARMER THAN NORMAL IN DECEMBER...

THE AVERAGE TEMPERATURE FOR CASPER IN DECEMBER WAS 30.1 DEGREES
WHICH WAS 5.3 DEGREES ABOVE NORMAL. THIS WAS THE 9TH WARMEST
DECEMBER WITH RECORDS GOING BACK TO 1939. THE WARMEST READING FOR
THE MONTH WAS 66 DEGREES ON THE 2ND...WHICH BROKE THE 1939 RECORD OF
66. THE 1ST HIT 63 DEGREES...WHICH TIED THE 1995 RECORD. THE COLDEST
TEMPERATURE WAS 9 BELOW ZERO ON THE 17TH AND 28TH.

PRECIPITATION FOR THE MONTH WAS 0.63 INCHES...WHICH IS 103 PERCENT
OF NORMAL. THE WETTEST 24-HOUR PERIOD WAS THE 9TH-10TH WHEN 0.33
INCHES FELL. THERE WERE NO PRECIPITATION OR SNOW RECORDS BROKEN THIS
MONTH.

THE TOTAL SNOWFALL IN DECEMBER WAS 9.6 INCHES...WHICH IS 1.4 INCHES
BELOW NORMAL. THE SNOWIEST DAY WAS ON THE 15TH WITH 3.6 INCHES OF
SNOW. THE HIGHEST WIND GUST WAS 66 MPH FROM THE SOUTHWEST ON THE
14TH.

...THE CASPER WY CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2021...

CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1939 TO 2021

WEATHER         OBSERVED          NORMAL  DEPART   LAST YEAR`S
                VALUE   DATE(S)   VALUE   FROM     VALUE
                                          NORMAL
..............................................................
TEMPERATURE (F)
RECORD
 HIGH             66   12/02/2021
 LOW             -41   12/21/1939
HIGHEST           66R  12/02
LOWEST            -9   12/17
                       12/28
AVG. MAXIMUM    41.7               34.7     7.0
AVG. MINIMUM    18.5               14.8     3.7
MEAN            30.1               24.8     5.3
DAYS MAX >= 90     0
DAYS MAX <= 32     8
DAYS MIN <= 32    26
DAYS MIN <= 0      3

PRECIPITATION (INCHES)
RECORD
 MAXIMUM        3.71   1982
 MINIMUM        0.03   1952
TOTALS          0.63               0.61    0.02     0.68
DAILY AVG.      0.02               0.02    0.00
DAYS >= .01        8
DAYS >= .10        3
DAYS >= .50        0
DAYS >= 1.00       0
GREATEST
 24 HR. TOTAL   0.33   12/09 TO 12/10
 STORM TOTAL    0.23

SNOWFALL (INCHES)
TOTALS           9.6               11.0    -1.4
SINCE 7/1       30.4               28.4     2.0
SNOWDEPTH AVG.     0
DAYS >= 1.0        3

DEGREE DAYS
HEATING TOTAL   1076               1248    -172
 SINCE 7/1      2499               3048    -549
COOLING TOTAL      0                  0       0
 SINCE 1/1       554                443     111
..............................................................

WIND (MPH)
AVERAGE WIND SPEED              18.8
RESULTANT WIND SPEED/DIRECTION  16/220
HIGHEST WIND SPEED/DIRECTION    49/220    DATE  12/11
HIGHEST GUST SPEED/DIRECTION    66/210    DATE  12/14

SKY COVER
POSSIBLE SUNSHINE (PERCENT)   MM
AVERAGE SKY COVER           0.22
NUMBER OF DAYS FAIR           23
NUMBER OF DAYS PC              7
NUMBER OF DAYS CLOUDY          1

AVERAGE RH (PERCENT)     55

WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM              0     MIXED PRECIP               0
HEAVY RAIN                0     RAIN                       0
LIGHT RAIN                3     FREEZING RAIN              0
LT FREEZING RAIN          0     HAIL                       0
HEAVY SNOW                1     SNOW                       3
LIGHT SNOW               13     SLEET                      0
FOG                      11     FOG W/VIS <= 1/4 MILE      2
HAZE                      7

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

LOOKING AHEAD TO JANUARY 2022...THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 34 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 14 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 36
DEGREES...AND THE AVERAGE LOW TEMPERATURE IS 15. THE AVERAGE MONTHLY
PRECIPITATION IS 0.49 INCHES...AND THE AVERAGE MONTHLY SNOWFALL IS 9
INCHES.

$$