448
WWUS75 KRIW 182357
NPWRIW
URGENT - WEATHER MESSAGE
NATIONAL WEATHER SERVICE RIVERTON WY
557 PM MDT MON MAY 18 2026
WYZ003>006-010-011-191500-
/O.NEW.KRIW.FZ.W.0003.260519T0300Z-260519T1500Z/
CODY FOOTHILLS-NORTH BIGHORN BASIN-SOUTHWEST BIGHORN BASIN-
SOUTHEAST BIGHORN BASIN-NORTHEAST JOHNSON COUNTY-SOUTHEAST
JOHNSON COUNTY-
INCLUDING THE CITIES OF GREYBULL, WORLAND, MEETEETSE, KAYCEE,
CLARK, CODY, POWELL, SHELL, LOVELL, TEN SLEEP, BASIN,
THERMOPOLIS, AND BUFFALO
557 PM MDT MON MAY 18 2026
...FREEZE WARNING IN EFFECT FROM 9 PM THIS EVENING TO 9 AM MDT
TUESDAY...
* WHAT...LOW TEMPERATURES OF 24 TO 28 DEGREES.
* WHERE...SOUTHWEST BIGHORN BASIN, NORTHEAST JOHNSON COUNTY,
SOUTHEAST BIGHORN BASIN, SOUTHEAST JOHNSON COUNTY, CODY FOOTHILLS,
AND NORTH BIGHORN BASIN.
* WHEN...FROM 9 PM MONDAY EVENING TO 9 AM MDT TUESDAY.
* IMPACTS...FROST AND FREEZE CONDITIONS COULD KILL CROPS, OTHER
SENSITIVE VEGETATION AND POSSIBLY DAMAGE UNPROTECTED OUTDOOR
PLUMBING.
* ADDITIONAL DETAILS...A CLEARING SKY OVERNIGHT WILL ALLOW FOR
TEMPERATURES TO FALL WELL BELOW SEASONAL NORMALS.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TAKE STEPS NOW TO PROTECT TENDER PLANTS FROM THE COLD.
TO PREVENT WATER PIPES FROM FREEZING, WRAP OR DRAIN WATER LINES.
WYZ016>020-191500-
/O.NEW.KRIW.FZ.W.0003.260519T0300Z-260519T1500Z/
UPPER WIND RIVER BASIN-WIND RIVER BASIN-LANDER FOOTHILLS-GREEN
MOUNTAINS AND RATTLESNAKE RANGE-NATRONA COUNTY LOWER ELEVATIONS-
INCLUDING THE CITIES OF CASPER, LANDER, JEFFREY CITY, RIVERTON,
SHOSHONI, AND DUBOIS
557 PM MDT MON MAY 18 2026
...FREEZE WARNING IN EFFECT FROM 9 PM THIS EVENING TO 9 AM MDT
TUESDAY...
* WHAT...LOW TEMPERATURES OF 20 TO 24 DEGREES, WITH COLDER
TEMPERATURES OF 15 TO 20 DEGREES POSSIBLE IN SNOW-COVERED AREAS
ABOVE 6,000 FEET.
* WHERE...GREEN MOUNTAINS AND RATTLESNAKE RANGE, LANDER FOOTHILLS,
NATRONA COUNTY LOWER ELEVATIONS, UPPER WIND RIVER BASIN, AND WIND
RIVER BASIN.
* WHEN...FROM 9 PM MONDAY EVENING TO 9 AM MDT TUESDAY.
* IMPACTS...FROST AND FREEZE CONDITIONS COULD KILL CROPS, OTHER
SENSITIVE VEGETATION AND POSSIBLY DAMAGE UNPROTECTED OUTDOOR
PLUMBING.
* ADDITIONAL DETAILS...OVERNIGHT LOWS COULD BE A FEW DEGREES WARMER
IF CLOUD COVER DOES NOT CLEAR EARLY TUESDAY. SUB-FREEZING
TEMPERATURES WOULD STILL OCCUR.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
TAKE STEPS NOW TO PROTECT TENDER PLANTS FROM THE COLD.
TO PREVENT WATER PIPES FROM FREEZING, WRAP OR DRAIN WATER LINES.
FOR MORE INFORMATION FROM THE NATIONAL WEATHER SERVICE, VISIT
HTTPS://WEATHER.GOV/RIW/ .
CNJ
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