357  
WGUS65 KPIH 181630  
FFAPIH  
 
URGENT - IMMEDIATE BROADCAST REQUESTED  
FLOOD WATCH  
NATIONAL WEATHER SERVICE POCATELLO ID  
1030 AM MDT FRI SEP 18 2026  
 
IDZ053-190600-  
/O.CAN.KPIH.FF.A.0007.000000T0000Z-260919T0400Z/  
/O.NEW.KPIH.FA.A.0002.260918T1630Z-260919T0600Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
UPPER SNAKE RIVER PLAIN-  
INCLUDING THE CITIES OF REXBURG, IDAHO FALLS, AND ST. ANTHONY  
1030 AM MDT FRI SEP 18 2026  
   
..FLASH FLOOD WATCH FOR THE BIG ROCK BURN SCAR IS BEING EXPANDED
 
 
THE FLASH FLOOD WATCH FOR THE BIG ROCK BURN SCAR IS BEING REPLACED  
WITH A MORE BROAD FLASH FLOOD WATCH ACROSS EASTERN IDAHO.  
 

 
   
..FLASH FLOOD WATCH IN EFFECT THROUGH THIS EVENING
 
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...A PORTION OF SOUTHEAST IDAHO, INCLUDING THE FOLLOWING AREA,  
UPPER SNAKE RIVER PLAIN.  
 
* WHEN...THROUGH THIS EVENING.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
FLOODING MAY OCCUR IN POOR DRAINAGE AND URBAN AREAS. STORM DRAINS  
AND DITCHES MAY BECOME CLOGGED WITH DEBRIS.  
 
* ADDITIONAL DETAILS...  
- HEAVY RAINFALL FROM THUNDERSTORMS IS EXPECTED THROUGH THIS  
EVENING ACROSS EASTERN IDAHO. RAINFALL AMOUNTS IN EXCESS OF 0.50"  
ARE POSSIBLE, LEADING TO FLOODING WITHIN BURN SCARS, STEEP  
TERRAIN, AND URBAN AREAS.  
- HTTP://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION  
SHOULD FLASH FLOOD WARNINGS BE ISSUED.  
 

 
 

 
 
IDZ052-054-058>068-070>073-075-190600-  
/O.NEW.KPIH.FA.A.0002.260918T1630Z-260919T0600Z/  
/00000.0.ER.000000T0000Z.000000T0000Z.000000T0000Z.OO/  
ARCO/MUD LAKE DESERT-LOWER SNAKE RIVER PLAIN-MARSH AND ARBON  
HIGHLANDS-FRANKLIN/EASTERN ONEIDA REGION-BEAR RIVER RANGE-BEAR  
LAKE VALLEY-BLACKFOOT MOUNTAINS-CARIBOU RANGE-BIG HOLE MOUNTAINS-  
TETON VALLEY-CENTENNIAL MOUNTAINS - ISLAND PARK-BEAVERHEAD -  
LEMHI HIGHLANDS-LOST RIVER VALLEY-CHALLIS/PAHSIMEROI VALLEYS-  
FRANK CHURCH WILDERNESS-SAWTOOTH/STANLEY BASIN-SUN VALLEY REGION-  
WOOD RIVER FOOTHILLS-  
INCLUDING THE CITIES OF MONTPELIER, CRATERS OF THE MOON NM, SHELLEY,  
DOWNEY, TETONIA, CHILLY, ARCO, MALAD, VICTOR, EMIGRATION SUMMIT,  
GRACE, STANLEY, INL, CHALLIS, KILGORE, BLACKFOOT, SPENCER, DUBOIS,  
GEORGETOWN, LAVA HOT SPRINGS, AMERICAN FALLS, PRESTON, SMALL, FORT  
HALL, GALENA, DRIGGS, SODA SPRINGS, MCCAMMON, ISLAND PARK, CLAYTON,  
BELLEVUE, PICABO, SUN VALLEY, MUD  
LAKE, POCATELLO, ST. CHARLES, BONE, HENRY, HOWE, ASHTON, WAYAN,  
MACKAY, THATCHER, HAILEY, SWAN VALLEY, INKOM, KETCHUM, AND EDIE  
SCHOOL  
1030 AM MDT FRI SEP 18 2026  
   
..FLASH FLOOD WATCH IN EFFECT THROUGH THIS EVENING
 
 
* WHAT...FLASH FLOODING CAUSED BY EXCESSIVE RAINFALL IS POSSIBLE.  
 
* WHERE...PORTIONS OF CENTRAL, EASTERN, AND SOUTHEAST IDAHO,  
INCLUDING THE FOLLOWING AREAS, IN CENTRAL IDAHO, CHALLIS/PAHSIMEROI  
VALLEYS, FRANK CHURCH WILDERNESS, LOST RIVER VALLEY,  
SAWTOOTH/STANLEY BASIN, SUN VALLEY REGION AND WOOD RIVER FOOTHILLS.  
IN EASTERN IDAHO, BEAVERHEAD - LEMHI HIGHLANDS, BIG HOLE MOUNTAINS,  
CENTENNIAL MOUNTAINS - ISLAND PARK AND TETON VALLEY. IN SOUTHEAST  
IDAHO, ARCO/MUD LAKE DESERT, BEAR LAKE VALLEY, BEAR RIVER RANGE,  
BLACKFOOT MOUNTAINS, CARIBOU RANGE, FRANKLIN/EASTERN ONEIDA REGION,  
LOWER SNAKE RIVER PLAIN AND MARSH AND ARBON HIGHLANDS.  
 
* WHEN...THROUGH THIS EVENING.  
 
* IMPACTS...EXCESSIVE RUNOFF MAY RESULT IN FLOODING OF RIVERS,  
CREEKS, STREAMS, AND OTHER LOW-LYING AND FLOOD-PRONE LOCATIONS.  
FLOODING MAY OCCUR IN POOR DRAINAGE AND URBAN AREAS. STORM DRAINS  
AND DITCHES MAY BECOME CLOGGED WITH DEBRIS.  
 
* ADDITIONAL DETAILS...  
- HEAVY RAINFALL FROM THUNDERSTORMS IS EXPECTED THROUGH THIS  
EVENING ACROSS CENTRAL AND EASTERN IDAHO. RAINFALL AMOUNTS IN  
EXCESS OF 0.50" ARE POSSIBLE, LEADING TO FLOODING WITHIN BURN  
SCARS, STEEP TERRAIN, AND URBAN AREAS.  
- HTTP://WWW.WEATHER.GOV/SAFETY/FLOOD  
 
PRECAUTIONARY/PREPAREDNESS ACTIONS...  
 
YOU SHOULD MONITOR LATER FORECASTS AND BE PREPARED TO TAKE ACTION  
SHOULD FLASH FLOOD WARNINGS BE ISSUED.  
 

 
 

 
 
JKEYES  
 
CLICK HERE TO GO TO PREVIOUS BULLETINS.

The Nexlab ID Page Main Text Page