There is a slight risk of severe weather for Sunday (mainly in the evening into the overnight hours) for most of the state of Iowa. It covers all of the state except far NW Iowa and the SE part of the state.

POTENTIAL MID/UPPER FORCING FOR CONVECTIVE DEVELOPMENT ON SUNDAY IS STILL UNCLEAR. HOWEVER…MODELS CONTINUE TO INDICATE MID 60S TO NEAR 70F SURFACE DEW POINTS WILL RETURN NORTHWARD THROUGH THE CENTRAL U.S…ALONG AND AHEAD OF A COLD FRONT WHICH IS EXPECTED TO STALL AND WEAKEN BEFORE RETREATING OR REDEVELOPING NORTHWARD…TO THE WEST AND THE NORTH OF THE UPPER RIDGE. AND IT APPEARS PROBABLE THAT A PRE-FRONTAL CORRIDOR OF STRONGER HEATING WILL CONTRIBUTE TO MODERATE TO STRONG BOUNDARY LAYER INSTABILITY ACROSS PARTS OF WESTERN/NORTHERN KANSAS…NORTHWARD AND EASTWARD INTO WESTERN AND NORTHERN WISCONSIN.

THIS INSTABILITY…CHARACTERIZED BY CAPE UP TO 3000 J/KG…IS EXPECTED TO BECOME SUPPORTIVE OF AT LEAST SCATTERED STRONG/SEVERE STORM DEVELOPMENT…WHERE LOW-LEVEL FORCING BECOMES LOCALLY ENHANCED AND INHIBITION WEAKENS DURING THE HOURS NEAR AND SHORTLY AFTER PEAK HEATING. MODESTLY STRONG AND VEERING WIND FIELDS WITH HEIGHT IN LOWER/MID LEVELS PROBABLY WILL PROVIDE SUFFICIENT SHEAR FOR SUPERCELLS ACROSS THE PLAINS PORTION OF THE SLIGHT RISK AREA. MID/UPPER FLOW LIKELY WILL BE CONSIDERABLY WEAKER ACROSS UPPER MISSISSIPPI VALLEY PORTIONS…BUT MOMENTUM/SHEAR ASSOCIATED 25-30 KT SOUTHWESTERLY 850 MB FLOW MAY STILL BE ENOUGH TO ENHANCE STORM MOTIONS AND ORGANIZATION