000  
ACUS11 KWNS 282134  
SWOMCD  
SPC MCD 282134  
IDZ000-MTZ000-WAZ000-282330-  
 
MESOSCALE DISCUSSION 0883  
NWS STORM PREDICTION CENTER NORMAN OK  
0434 PM CDT THU MAY 28 2026  
 
AREAS AFFECTED...EASTERN WASHINGTON...THE IDAHO PANHANDLE...AND FAR  
NORTHWEST MONTANA  
 
CONCERNING...SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY  
 
VALID 282134Z - 282330Z  
 
PROBABILITY OF WATCH ISSUANCE...80 PERCENT  
 
SUMMARY...THE THREAT FOR SEVERE THUNDERSTORMS CAPABLE OF 60-75 MPH  
WIND GUSTS AND HAIL UP TO GOLF-BALL SIZE IS EXPECTED TO INCREASE  
FROM SOUTH TO NORTH ACROSS THE DISCUSSION AREA THIS AFTERNOON INTO  
EVENING. A SEVERE THUNDERSTORM WATCH WILL LIKELY BE REQUIRED.  
 
DISCUSSION...VISIBLE SATELLITE AND MOSAIC RADAR DATA INDICATE  
GRADUALLY DEEPENING CONVECTION ALONG THE SALMON RIVER MOUNTAINS AND  
ADJACENT HIGH TERRAIN OF THE SOUTHERN ID PANHANDLE INTO THE  
BITTERROOT MOUNTAINS IN WESTERN MT. FORCING FOR ASCENT DOWNSTREAM  
FROM A VIGOROUS SHORT-WAVE TROUGH PIVOTING NORTHWEST THROUGH THE  
NORTHERN GREAT BASIN IN CONJUNCTION WITH HEATING/DESTABILIZATION  
ALONG THE HIGH TERRAIN ARE CONTRIBUTING TO THE CONVECTIVE  
DEVELOPMENT, WITH SCATTERED THUNDERSTORMS EVENTUALLY EVOLVING IN  
THESE AREAS.  
 
STRONG DAYTIME HEATING ACROSS THE DISCUSSION AREA WILL COMBINE WITH  
BOUNDARY-LAYER DEWPOINTS IN THE 50S TO SUPPORT FURTHER AIR MASS  
DESTABILIZATION THROUGH THE PEAK OF THE DIURNAL HEATING CYCLE, WITH  
THE PRESENCE OF STEEP LOW/MID-LEVEL LAPSE RATES YIELDING MLCAPE AS  
HIGH AS 1500-2500 J/KG. THE DESTABILIZATION PROCESS WILL COINCIDE  
WITH GRADUALLY STRENGTHENING MID- TO HIGH-LEVEL WINDS WITH EFFECTIVE  
BULK SHEAR INCREASING TO 30-40 KT, WHICH WILL FAVOR ORGANIZED STORM  
MODES, INCLUDING SUPERCELLS AND BOWING STRUCTURES CAPABLE OF WIND  
GUSTS UP TO 60-75 MPH AND HAIL UP TO GOLF-BALL SIZE.  
 
..MEAD/GUYER.. 05/28/2026  
   
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT  
 
ATTN...WFO...MSO...OTX...PDT...  
 
LAT...LON 45471474 45421568 45781646 46041692 46071739 46121828  
46811874 47721887 48471865 48651815 48681723 48811646  
48721554 48221500 47481460 46841427 46111420 45471474  
 
MOST PROBABLE PEAK WIND GUST...65-80 MPH  
MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN  
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