385
CXUS55 KRIW 092058 CCA
CLMRKS
CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
121 PM MST FRI JAN 09 2026
...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR ROCK SPRINGS FOR THE
MONTH OF DECEMBER 2025...
...OFFICIAL CLIMATE DATA FOR THE MONTH OF DECEMBER 2025 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
..ROCK SPRINGS WAS DRIER WITH RECORD WARMTH IN DECEMBER
THE AVERAGE TEMPERATURE FOR ROCK SPRINGS IN DECEMBER WAS 35.6
DEGREES WHICH WAS 14.2 DEGREES ABOVE NORMAL. IT WAS THE WARMEST
DECEMBER SINCE RECORDS BEGAN IN 1948. THE WARMEST READING FOR THE
MONTH WAS 59 DEGREES ON THE 22ND AND BROKE THE 1964 RECORD OF 47. IT
ALSO SET A NEW ALL-TIME MONTHLY HIGH FOR DECEMBER. PREVIOUS RECORD
WAS 58 DEGREES SET DECEMBER 12 2021. SEVERAL OTHER DAILY HIGH
RECORDS WERE BROKEN AND ARE LISTED BELOW. THE COLDEST TEMPERATURE
WAS 10 DEGREES ON THE 28TH.
DATENEW OLDYEAR
11TH53 512004
12TH51(T) 512004
13TH51 49 2010
16TH51(T) 511980
19TH54 491969
23RD56 481969
24TH51 46 1955
25TH55 471980
PRECIPITATION FOR THE MONTH WAS 0.10 INCHES...WHICH WAS 32 PERCENT
OF NORMAL. THE WETTEST 24-HOUR PERIOD WAS ON THE 17TH WITH 0.04
INCHES. NO PRECIPITATION RECORDS WERE BROKEN THIS MONTH. THE HIGHEST
WIND GUST WAS 79 MPH FROM THE WEST ON THE 17TH.
...THE ROCK SPRINGS WY CLIMATE SUMMARY FOR THE MONTH OF DECEMBER
2025...
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1948 TO 2026
WEATHER OBSERVED NORMAL DEPART LAST YEAR'S
VALUE DATE(S) VALUE FROM VALUE
NORMAL
..........................................................
TEMPERATURE (F)
RECORD
HIGH 58 12/02/2021
LOW -29 12/22/1990
12/21/1990
12/31/1978
HIGHEST 59R 12/22
LOWEST 10 12/28
AVG. MAXIMUM 44.6R 29.5 15.1
AVG. MINIMUM 26.5R 13.4 13.1
MEAN 35.6R 21.4 14.2
DAYS MAX >= 90 0
DAYS MAX <= 32 4
DAYS MIN <= 32 22
DAYS MIN <= 0 0
PRECIPITATION (INCHES)
RECORD
MAXIMUM 1.78 1975
MINIMUM 0.00 1962
TOTALS 0.10 0.31 -0.21 0.18
DAILY AVG. 0.00 0.01 -0.01
DAYS >= .01 4
DAYS >= .10 0
DAYS >= .50 0
DAYS >= 1.00 0
GREATEST
24 HR. TOTAL 0.04 12/17 TO 12/17
STORM TOTAL 0.04
SNOWFALL (INCHES)
TOTALS MM 5.8 MM
SINCE 7/1 MM 19.6 MM
SNOWDEPTH AVG. MM
DAYS >= 1.0 MM
DEGREE DAYS
HEATING TOTAL 905 1350 -445
SINCE 7/1 2397 3297 -900
COOLING TOTAL 0 0 0
SINCE 1/1 442 320 122
..........................................................
WIND (MPH)
AVERAGE WIND SPEED 17.5
RESULTANT WIND SPEED/DIRECTION 15/250
HIGHEST WIND SPEED/DIRECTION 61/260 DATE 12/17
HIGHEST GUST SPEED/DIRECTION 79/260 DATE 12/17
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.32
NUMBER OF DAYS FAIR 16
NUMBER OF DAYS PC 14
NUMBER OF DAYS CLOUDY 1
AVERAGE RH (PERCENT) 55
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 1 MIXED PRECIP 0
HEAVY RAIN 0 RAIN 0
LIGHT RAIN 7 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 0
LIGHT SNOW 8 SLEET 0
FOG 7 FOG W/VIS <= 1/4 MILE 0
HAZE 0
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
LOOKING AHEAD TO JANUARY 2026. THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 29 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 13 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 30
DEGREES AND THE AVERAGE LOW TEMPERATURE IS 14. THE AVERAGE MONTHLY
PRECIPITATION IS 0.38 INCHES.
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