501
CXUS55 KRIW 011644
CLMP60
CLIMATE REPORT
NATIONAL WEATHER SERVICE RIVERTON WY
1032 AM MDT MON JUN 01 2026
...PRELIMINARY MONTHLY CLIMATE SUMMARY FOR LAKE YELLOWSTONE FOR THE
MONTH OF MAY 2026...
...OFFICIAL CLIMATE DATA FOR THE MONTH OF MAY 2026 WILL BE AVAILABLE
APPROXIMATELY IN 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
..LAKE YELLOWSTONE IN WARMER AND DRIER THAN NORMAL IN MAY
AVERAGE TEMPERATURE FOR LAKE YELLOWSTONE IN MAY WAS 41.2 DEGREES
WHICH IS 2.8 DEGREES ABOVE NORMAL. IT WAS THE 5TH WARMEST MAY SINCE
RECORDS BEGAN IN 1998. THE WARMEST READING OF THE MONTH WAS 72
DEGREES ON THE 18TH AND ALSO ON THE 13TH WHICH BROKE THE 2013 RECORD
OF 70. THE 11TH HIT 69 AND BROKE THE 2007 RECORD OF 68. THE COLDEST
READING OF THE MONTH WAS 16 DEGREES ON THE 6TH AND 19TH. THE LOW OF
21 DEGREES ON THE 22ND BROKE THE 2022 RECORD OF 22.
TOTAL PRECIPITATION AT LAKE YELLOWSTONE WAS 0.97 INCHES...WHICH WAS
41 PERCENT OF NORMAL. IT WAS THE 4TH DRIEST MAY ON RECORD. THE
WETTEST 24-HOUR PERIOD DURING THE MONTH WAS THE 21ST WITH 0.41
INCHES. NO PRECIPITATION RECORDS WERE BROKEN THIS MONTH. THE HIGHEST
WIND GUST WAS 39 MPH FROM THE WEST ON THE 13TH.
...THE LAKE YELLOWSTONE WY CLIMATE SUMMARY FOR THE MONTH OF MAY
2026...
CLIMATE NORMAL PERIOD: 1991 TO 2020
CLIMATE RECORD PERIOD: 1998 TO 2026
WEATHER OBSERVED NORMAL DEPART LAST YEAR'S
VALUE DATE(S) VALUE FROM VALUE
NORMAL
..........................................................
TEMPERATURE (F)
RECORD
HIGH 78 05/28/2003
LOW 0 05/07/2010
HIGHEST 72 05/13
05/28
LOWEST 16 05/06
05/19
AVG. MAXIMUM 55.6 50.6 5.0
AVG. MINIMUM 26.8 26.3 0.5
MEAN 41.2 38.4 2.8
DAYS MAX >= 90 0
DAYS MAX <= 32 0
DAYS MIN <= 32 27
DAYS MIN <= 0 0
PRECIPITATION (INCHES)
RECORD
MAXIMUM 4.53 2022
MINIMUM 0.42 2019
TOTALS 0.97 2.35 -1.38 2.45
DAILY AVG. 0.03 0.08 -0.05
DAYS >= .01 11
DAYS >= .10 3
DAYS >= .50 0
DAYS >= 1.00 0
GREATEST
24 HR. TOTAL 0.41 05/21 TO 05/21
STORM TOTAL 0.41
DEGREE DAYS
HEATING TOTAL 708 823 -115
SINCE 7/1 9750 11473 -1723
COOLING TOTAL 0 0 0
SINCE 1/1 0 0 0
..........................................................
WIND (MPH)
AVERAGE WIND SPEED 3.1
RESULTANT WIND SPEED/DIRECTION 0/090
HIGHEST WIND SPEED/DIRECTION 23/270 DATE 05/11
HIGHEST GUST SPEED/DIRECTION 39/270 DATE 05/11
39/280 05/13
SKY COVER
POSSIBLE SUNSHINE (PERCENT) MM
AVERAGE SKY COVER 0.00
NUMBER OF DAYS FAIR 31
NUMBER OF DAYS PC 0
NUMBER OF DAYS CLOUDY 0
AVERAGE RH (PERCENT) 59
WEATHER CONDITIONS. NUMBER OF DAYS WITH
THUNDERSTORM 0 MIXED PRECIP 0
HEAVY RAIN 0 RAIN 0
LIGHT RAIN 9 FREEZING RAIN 0
LT FREEZING RAIN 0 HAIL 0
HEAVY SNOW 0 SNOW 0
LIGHT SNOW 5 SLEET 0
FOG 0 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 JUNE 2026. THE AVERAGE HIGH TEMPERATURE ON THE
FIRST OF THE MONTH IS 56 DEGREES...AND THE AVERAGE LOW TEMPERATURE
IS 31 DEGREES. THE AVERAGE HIGH BY THE END OF THE MONTH IS 68
DEGREES AND THE AVERAGE LOW TEMPERATURE IS 36 DEGREES. THE AVERAGE
MONTHLY PRECIPITATION IS 2.38 INCHES.
CLICK HERE TO GO TO PREVIOUS BULLETINS.
Main Text Page