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CXUS55 KRIW 092053 CCA
CLMRIW
CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
121 PM MST FRI JAN 09 2026
...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR RIVERTON 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
..RIVERTON WAS DRIER WITH RECORD WARMTH IN DECEMBER.
THE AVERAGE TEMPERATURE FOR RIVERTON IN DECEMBER WAS 35.3 DEGREES
WHICH WAS 15.7 DEGREES ABOVE NORMAL. IT WAS THE WARMEST DECEMBER
SINCE RECORDS BEGAN IN 1996. THE WARMEST READING FOR THE MONTH WAS
64 DEGREES ON THE 24TH AND BROKE THE 2021 RECORD OF 47. IT ALSO SET
A NEW RECORD FOR ALL-TIME MONTHLY HIGH FOR DECEMBER. SEVERAL DAILY
HIGH RECORDS WERE BROKEN AND ARE LISTED BELOW. THE COLDEST READING
WAS 1 DEGREE ON THE 1ST.
DATENEW OLDYEAR
9TH 58 562015
10TH56 531996
11TH59(T) 592004
12TH59 531995
16TH62 552012
17TH58(T) 582013
19TH55 462024
21ST52 512021
22ND59 532024
23RD57 482021
25TH55 412021
26TH 48 472006
27TH45(T) 452005
PRECIPITATION FOR THE MONTH WAS 0.18 INCHES...WHICH IS 69 PERCENT OF
NORMAL. THE WETTEST 24-HOURS WAS THE 2ND-3RD WHEN 0.14 INCHES FELL.
NO PRECIPITATION OR SNOWFALL RECORDS WERE BROKEN THIS MONTH.
SNOWFALL FOR THE MONTH WAS 1.5 INCHES. THE SNOWIEST 24-HOURS WAS ON
THE 2ND-3RD WHEN 1.5 INCHES FELL. THE HIGHEST WIND GUST WAS 73 MPH
FROM THE SOUTHWEST AND OCCURRED ON THE 10TH.
..THE RIVERTON WY CLIMATE SUMMARY FOR THE MONTH OF DECEMBER 2025
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1995 TO 2026
WEATHER OBSERVED NORMAL DEPART LAST YEAR'S
VALUE DATE(S) VALUE FROM VALUE
NORMAL
..........................................................
TEMPERATURE (F)
RECORD
HIGH 61 12/01/2021
12/01/1995
12/02/2021
LOW -31 12/22/2022
HIGHEST 64R 12/24
LOWEST 1 12/01
AVG. MAXIMUM 47.5R 30.8 16.7
AVG. MINIMUM 23.0R 8.4 14.6
MEAN 35.3R 19.6 15.7
DAYS MAX >= 90 0
DAYS MAX <= 32 4
DAYS MIN <= 32 26
DAYS MIN <= 0 0
PRECIPITATION (INCHES)
RECORD
MAXIMUM 0.79 2022
MINIMUM T 2001
TOTALS 0.18 0.26 -0.08 0.05
DAILY AVG. 0.01 0.01 0.00
DAYS >= .01 4
DAYS >= .10 1
DAYS >= .50 0
DAYS >= 1.00 0
GREATEST
24 HR. TOTAL 0.14 12/02 TO 12/03
STORM TOTAL 0.11
SNOWFALL (INCHES)
TOTALS 1.5 MM MM
SINCE 7/1 3.5 MM MM
SNOWDEPTH AVG. 0
DAYS >= 1.0 1
DEGREE DAYS
HEATING TOTAL 912 1407 -495
SINCE 7/1 2355 3306 -951
COOLING TOTAL 0 0 0
SINCE 1/1 611 499 112
..........................................................
WIND (MPH)
AVERAGE WIND SPEED 10.3
RESULTANT WIND SPEED/DIRECTION 5/270
HIGHEST WIND SPEED/DIRECTION 47/290 DATE 12/17
HIGHEST GUST SPEED/DIRECTION 73/250 DATE 12/10
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.11
NUMBER OF DAYS FAIR 29
NUMBER OF DAYS PC 2
NUMBER OF DAYS CLOUDY 0
AVERAGE RH (PERCENT) 56
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 0 SNOW 1
LIGHT SNOW 4 SLEET 0
FOG 4 FOG W/VIS <= 1/4 MILE 2
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 30 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 7 DEGREES. THE AVERAGE HIGH AT THE END OF THE MONTH IS 32 DEGREES
AND THE AVERAGE LOW TEMPERATURE IS 9. THE AVERAGE MONTHLY
PRECIPITATION IS 0.29 INCHES.
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