703  
ACUS01 KWNS 301234  
SWODY1  
SPC AC 301232  
 
DAY 1 CONVECTIVE OUTLOOK  
NWS STORM PREDICTION CENTER NORMAN OK  
0732 AM CDT MON MAR 30 2026  
 
VALID 301300Z - 311200Z  
 
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF  
THE MIDDLE AND UPPER MISSISSIPPI VALLEY...  
   
..SUMMARY  
 
A FEW SEVERE THUNDERSTORMS WITH LARGE HAIL, ARE EXPECTED ACROSS  
PARTS OF THE MIDDLE AND UPPER MISSISSIPPI RIVER VALLEY TONIGHT  
THROUGH EARLY TUESDAY MORNING. ISOLATED STRONG TO MARGINALLY SEVERE  
STORMS COULD OCCUR FURTHER EAST INTO PARTS OF LOWER MICHIGAN EARLY  
TUESDAY MORNING AS WELL AS OVER THE TEXAS SOUTH PLAINS THIS  
AFTERNOON AND EVENING.  
   
..SYNOPSIS  
 
EARLY-MORNING SATELLITE IMAGERY SHOWS A RELATIVELY ZONAL PATTERN IN  
PLACES ACROSS THE MAJORITY OF THE CONUS. THE ONLY EXCEPTION IS  
ACROSS THE GULF COAST, WHICH IS ALONG THE NORTHERN PERIPHERY OF  
MODEST SUBTROPICAL RIDGING. RECENT SURFACE ANALYSIS SHOWS A BROAD  
AREA OF LOW PRESSURE ACROSS THE CENTRAL HIGH PLAINS/CENTRAL PLAINS  
WITH SEVERAL EMBEDDED LOWS, INCLUDING ONE OVER SOUTHWEST SD, ANOTHER  
OVER SOUTH-CENTRAL NE, AND ANOTHER NEAR THE OK/KS/CO BORDER  
INTERSECTION. MODEST TROUGHING EXTENDS BETWEEN THESE FEATURES, WHILE  
A STATIONARY FRONT EXTENDS FROM THE SOUTHWEST SD LOW  
EAST-NORTHEASTWARD ACROSS SOUTHERN MN AND CENTRAL WI. AT 11Z, MID  
50S DEWPOINTS EXTENDED FROM SOUTH-CENTRAL OK INTO THE MID-SOUTH,  
WITH 60S DEWPOINTS FARTHER SO FROM CENTRAL TX INTO THE LOWER MS  
VALLEY.  
 
OVERALL UPPER PATTERN IS EXPECTED TO REMAIN PREDOMINANTLY ZONAL  
THROUGHOUT THE PERIOD AS A LOW-AMPLITUDE SHORTWAVE TROUGH MOVES  
ALONG THE US/CANADA BORDER, ACCOMPANIED BY A STRENGTHENING JET  
STREAK. SUBSTANTIAL LOW-LEVEL MOISTURE ADVECTION IS EXPECTED  
THROUGHOUT THE DAY FROM THE SOUTHERN PLAINS/LOWER MS VALLEY INTO THE  
MID MS AND OH VALLEYS AND LOWER MI. BY EARLY TOMORROW MORNING, MID  
50S DEWPOINTS WILL LIKELY EXTEND FROM SOUTHERN WI ACROSS LOWER MI  
AND INTO THE UPPER OH VALLEY, DEMARCATING A DEVELOPING WARM FRONT.  
 
PRIMARY AREA OF THUNDERSTORM DEVELOPMENT ANTICIPATED TODAY IS IN THE  
VICINITY OF THE DEVELOPING WARM FRONT FROM THE MID/UPPER MS VALLEY  
ACROSS THE LOWER GREAT LAKES INTO THE UPPER OH VALLEY AND NORTHEAST.  
ISOLATED THUNDERSTORMS ARE ALSO POSSIBLE WITH THE MOIST AND  
CONFLUENT ENVIRONMENTS OF THE FL PENINSULA AND THE LOWER MS VALLEY  
AS WELL AS ALONG THE DRYLINE IN THE SOUTHERN HIGH PLAINS AND  
SEASONABLY MOIST AIRMASS OVER THE SOUTHWEST.  
   
...MID/UPPER MS VALLEY INTO LOWER MI AND THE UPPER OH VALLEY  
 
SIGNIFICANT LOW-LEVEL MOISTURE ADVECTION IS EXPECTED THROUGHOUT THE  
DAY INTO MID MS VALLEY, ALTHOUGH THIS ADVECTION WILL BE OFFSET  
SOMEWHAT BY STRONG HEATING AND DEEP BOUNDARY-LAYER MIXING. GENERAL  
EXPECTATION IS THAT UPPER 50S DEWPOINTS WILL REACH THE IA/MO/CENTRAL  
IL VICINITY BY 00Z, WITH MID 50S FARTHER NORTH INTO SOUTHERN WI AND  
SOUTHERN LOWER MI. GIVEN NEGLIGIBLE LARGE-SCALE FORCING AND STRONG  
MIXING, CAPPING IS EXPECTED PREVAIL THROUGHOUT THE DAY AND INTO THE  
EARLY EVENING. HOWEVER, BEGINNING AROUND 22-00Z, INCREASING  
MID-LEVEL MOISTURE COUPLED WITH CONTINUED LOW-LEVEL MOISTURE  
ADVECTION AND CONVERGENCE NEAR A WEAK SURFACE LOW COULD RESULT IN  
CONVECTIVE INITIATION ACROSS CENTRAL IA. THE EARLIEST DEVELOPMENT  
COULD BE SURFACE BASED WITH A TREND TOWARDS MORE ELEVATED STORMS  
WITH TIME AND NORTHEASTWARD EXTENT AS WARM-AIR ADVECTION INCREASE  
DURING THE EVENING. STEEP LAPSE RATES AND MODERATE SHEAR SUPPORT THE  
POTENTIAL FOR SUPERCELLS WITH ANY MORE SUSTAINED UPDRAFTS. LARGE TO  
ISOLATED VERY LARGE HAIL IS THE PRIMARY SEVERE RISK. EVEN WITH THE  
ELEVATED STORM CHARACTER, THE PREVAILING WARM/DRY CONDITIONS ABOVE  
THE SHALLOW RETURN MOISTURE COULD SUPPORT STRONG DOWNDRAFTS WITH  
STRONG SURFACE GUSTS.  
 
FARTHER EAST, A FEW INSTANCES OF SMALL HAIL ARE POSSIBLE FROM  
WESTERN PA INTO WESTERN NY WITH THE THUNDERSTORMS EXPECTED DURING  
THE EVENING AND OVERNIGHT.  
   
..SOUTHERN HIGH PLAINS  
 
ISOLATED THUNDERSTORM DEVELOPMENT IS POSSIBLE ALONG A DRYLINE  
FORECAST TO EXTEND FROM A WEAK LOW IN WESTERN KS SOUTHWESTWARD INTO  
THE TX TRANS PECOS. BUOYANCY WILL BE WEAK AND VERTICAL SHEAR MODEST  
SO STORM STRUCTURES ARE NOT EXPECTED TO BE PARTICULARLY ROBUST OR  
LONG LIVED. HOWEVER, HIGH CLOUD BASES AND STEEP LOW-LEVEL LAPSE  
RATES COULD STILL SUPPORT A FEW STRONGER GUSTS AT THE SURFACE.  
 
..MOSIER/MARSH.. 03/30/2026  
 
 
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