038  
ACUS03 KWNS 130735  
SWODY3  
SPC AC 130734  
 
DAY 3 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0234 AM CDT MON JUL 13 2026  
 
VALID 151200Z - 161200Z  
   
..NO SEVERE THUNDERSTORM AREAS FORECAST  
 
   
..SUMMARY  
 
ORGANIZED SEVERE THUNDERSTORMS ARE NOT EXPECTED ACROSS THE US ON  
WEDNESDAY.  
   
.. SYNOPSIS  
 
A CONUS-WIDE MID-LEVEL RIDGE WILL REMAIN ENTRENCHED ACROSS THE  
CENTRAL US, WITH A CLOSED MID-LEVEL LOW LOCATED ON EITHER SIDE OF IT  
-- ONE OFF THE PACIFIC NORTHWEST COAST AND THE OTHER ACROSS EASTERN  
CANADA. A SHORT-WAVE TROUGH MOVING THROUGH THE ENHANCED MID-LEVEL  
FLOW WILL IMPINGE UPON THE NORTHWEST PERIPHERY OF THE US RIDGE,  
HALTING ITS WESTWARD EXPANSION. ON THE EASTERN SIDE, A STRONG  
SHORT-WAVE TROUGH WILL CONTINUE DIGGING SOUTHEAST ACROSS NEW  
ENGLAND, HELPING TO CARVE OUT A LONG WAVE TROUGH ACROSS EASTERN  
CANADA AND THE NORTHEASTERN US. THIS IN TURN WILL SUPPRESS THE US  
RIDGE SOUTHWARD ALONG THE EAST COAST, RESULTING IN A  
NORTHWEST-TO-SOUTHEAST RIDGE AXIS ACROSS THE EASTERN US.  
 
AT THE SURFACE, A COLD FRONT WILL PUSH SOUTH AND WESTWARD ACROSS  
SOUTHERN NEW ENGLAND TOWARD THE OHIO VALLEY AND MID-ATLANTIC. TO THE  
NORTH OF THIS BOUNDARY, SEASONABLY COOL AND DRY CONDITIONS WILL  
PREVAIL, WHILE ALONG AND SOUTH OF THIS BOUNDARY, HOT AND HUMID  
CONDITIONS CONTINUE.  
 
   
.. WESTERN AND CENTRAL MONTANA  
 
CONTINUED ENHANCED SOUTHWESTERLY MID-LEVEL FLOW WILL PREVAIL ACROSS  
THE NORTHERN ROCKIES ON WEDNESDAY. EMBEDDED WITHIN THIS FLOW WILL BE  
SUBTLE VORTICITY/SPEED MAXIMA. LARGE-SCALE ASCENT ASSOCIATED WITH  
THESE FEATURES, COMBINED WITH DIURNAL HEATING WILL SUPPORT SCATTERED  
THUNDERSTORMS ALONG THE HIGHER TERRAIN OF SOUTHWEST MONTANA. AFTER  
SEVERAL DAYS OF REPEATED CONVECTION ACROSS MONTANA AND IN THE  
MID-LEVEL LAPSE-RATE SOURCE REGION UPSTREAM, UNCERTAINTY REMAINS AS  
TO THE NUMBER AND INTENSITY OF THUNDERSTORMS THAT DO DEVELOP. SHOULD  
VIGOROUS CONVECTION DEVELOP, THE OVERALL STRENGTH OF THE MID-LEVEL  
FLOW WHEN COUPLED WITH STEEP LAPSE RATES WOULD SUPPORT SPORADIC  
STRONG THUNDERSTORM WINDS.  
 
..MARSH.. 07/13/2026  
 
 
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