586
CDUS45 KRIW 180740
CLICPR
CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1240 AM MST THU DEC 18 2025
...............................
..THE CASPER WY CLIMATE SUMMARY FOR DECEMBER 17 2025
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1939 TO 2025
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...............................................................
TEMPERATURE (F)
YESTERDAY
MAXIMUM 54 1:14 PM 60 1980 34 20 38
MINIMUM 30 11:22 PM -31 1964 14 16 18
AVERAGE 42 24 18
PRECIPITATION (IN)
YESTERDAY T 0.45 1970 0.02 -0.02 0.00
MONTH TO DATE 0.11 0.34 -0.23 0.01
SINCE DEC 1 0.11 0.34 -0.23 0.01
SINCE JAN 1 11.80 11.95 -0.15 9.13
SNOWFALL (IN)
YESTERDAY MM 7.4 1968 0.3 MM 0.0
MONTH TO DATE 1.0 6.0 -5.0 T
SINCE DEC 1 1.0 6.0 -5.0 T
SINCE JUL 1 5.3 23.4 -18.1 T
SNOW DEPTH MM
DEGREE DAYS
HEATING
YESTERDAY 23 41 -18 37
MONTH TO DATE 478 672 -194 540
SINCE DEC 1 478 672 -194 540
SINCE JUL 1 1904 2474 -570 2040
COOLING
YESTERDAY 0 0 0 0
MONTH TO DATE 0 0 0 0
SINCE DEC 1 0 0 0 0
SINCE JAN 1 467 443 24 538
...............................................................
WIND (MPH)
HIGHEST WIND SPEED 56 HIGHEST WIND DIRECTION NW (300)
HIGHEST GUST SPEED 78 HIGHEST GUST DIRECTION W (290)
AVERAGE WIND SPEED 29.1
SKY COVER
POSSIBLE SUNSHINE MM
AVERAGE SKY COVER 0.3
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
THUNDERSTORM
LIGHT RAIN
LIGHT SNOW
HAZE
RELATIVE HUMIDITY (PERCENT)
HIGHEST 74 3:00 PM
LOWEST 22 10:00 PM
AVERAGE 48
......................................................
THE CASPER WY CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 34 52 1994
MINIMUM TEMPERATURE (F) 14 -18 1983
SUNRISE AND SUNSET
DECEMBER 18 2025......SUNRISE 7:32 AM MST SUNSET 4:33 PM MST
DECEMBER 19 2025......SUNRISE 7:33 AM MST SUNSET 4:34 PM MST
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
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