534
CDUS45 KRIW 210727
CLICPR
CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
127 AM MDT THU MAY 21 2026
...............................
..THE CASPER WY CLIMATE SUMMARY FOR MAY 20 2026
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1939 TO 2026
WEATHER ITEM OBSERVED TIME RECORD YEAR NORMAL DEPARTURE LAST
VALUE (LST) VALUE VALUE FROM YEAR
NORMAL
...............................................................
TEMPERATURE (F)
YESTERDAY
MAXIMUM 63 4:05 PM 89 1954 69 -6 65
1964
MINIMUM 25 3:54 AM 24 2003 39 -14 33
AVERAGE 44 54 -10
PRECIPITATION (IN)
YESTERDAY 0.00 0.81 1975 0.07 -0.07 T
MONTH TO DATE 1.08 1.44 -0.36 0.72
SINCE MAR 1 2.52 3.69 -1.17 3.64
SINCE JAN 1 3.06 4.74 -1.68 4.36
SNOWFALL (IN)
YESTERDAY 0.0 8.4 1975 0.1 -0.1 0.0
MONTH TO DATE 2.5 2.3 0.2 0.3
SINCE MAR 1 13.9 23.1 -9.2 16.0
SINCE JUL 1 29.6 71.4 -41.8 26.5
SNOW DEPTH 0
DEGREE DAYS
HEATING
YESTERDAY 21 12 9 16
MONTH TO DATE 292 307 -15 264
SINCE MAR 1 1498 1896 -398 1813
SINCE JUL 1 5675 7258 -1583 6828
COOLING
YESTERDAY 0 0 0 0
MONTH TO DATE 0 0 0 0
SINCE MAR 1 0 0 0 0
SINCE JAN 1 0 0 0 0
...............................................................
WIND (MPH)
HIGHEST WIND SPEED 21 HIGHEST WIND DIRECTION SW (220)
HIGHEST GUST SPEED 30 HIGHEST GUST DIRECTION SW (210)
AVERAGE WIND SPEED 10.4
SKY COVER
POSSIBLE SUNSHINE MM
AVERAGE SKY COVER 0.1
WEATHER CONDITIONS
THE FOLLOWING WEATHER WAS RECORDED YESTERDAY.
NO SIGNIFICANT WEATHER WAS OBSERVED.
RELATIVE HUMIDITY (PERCENT)
HIGHEST 96 4:00 AM
LOWEST 20 4:00 PM
AVERAGE 58
......................................................
THE CASPER WY CLIMATE NORMALS FOR TODAY
NORMAL RECORD YEAR
MAXIMUM TEMPERATURE (F) 69 87 1964
2006
MINIMUM TEMPERATURE (F) 39 26 2001
SUNRISE AND SUNSET
MAY 21 2026...........SUNRISE 5:37 AM MDT SUNSET 8:28 PM MDT
MAY 22 2026...........SUNRISE 5:36 AM MDT SUNSET 8:29 PM MDT
- INDICATES NEGATIVE NUMBERS.
R INDICATES RECORD WAS SET OR TIED.
MM INDICATES DATA IS MISSING.
T INDICATES TRACE AMOUNT.
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