485
ACUS11 KWNS 201255
SWOMCD
SPC MCD 201255
IAZ000-WIZ000-MNZ000-201500-
MESOSCALE DISCUSSION 1670
NWS STORM PREDICTION CENTER NORMAN OK
0755 AM CDT MON JUL 20 2026
AREAS AFFECTED...FAR SOUTHEAST MINNESOTA...EASTERN IOWA
CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY
VALID 201255Z - 201500Z
PROBABILITY OF WATCH ISSUANCE...20 PERCENT
SUMMARY...AN ISOLATED WIND-DAMAGE THREAT WILL LIKELY CONTINUE WITH A
SHORT LINE OF STRONG TO SEVERE STORMS NEAR THE IOWA-MINNESOTA STATE
LINE. THIS LINE WILL MOVE SOUTH-SOUTHEASTWARD ACROSS EASTERN IOWA
OVER THE NEXT COUPLE OF HOURS. THE THREAT IS EXPECTED TO BE MARGINAL
AND WEATHER WATCH ISSUANCE APPEARS UNLIKELY.
DISCUSSION...THE LATEST SURFACE ANALYSIS SHOWS A NORTH-TO-SOUTH
CORRIDOR OF LOW-LEVEL MOISTURE FROM FAR WESTERN MISSOURI NORTHWARD
INTO WESTERN IOWA, ALONG WHICH DEWPOINTS ARE IN THE MID 70S F.
SLIGHTLY FURTHER EAST, THE RAP HAS AN AXIS OF MODERATE INSTABILITY
WITH MLCAPE IN THE 1000 TO 2000 J/KG RANGE ANALYZED OVER CENTRAL
IOWA. SCATTERED THUNDERSTORMS ARE ONGOING ALONG THE INSTABILITY
GRADIENT TO THE EAST OF THIS AXIS. THE STORMS ARE BEING SUPPORTED BY
A SUBTLE MID-LEVEL SHORTWAVE TROUGH EVIDENT ON WATER VAPOR IMAGERY
MOVING SOUTHEASTWARD ACROSS THE UPPER MISSISSIPPI VALLEY. ALTHOUGH
FORECAST SOUNDINGS ACROSS EASTERN IOWA THIS MORNING HAVE A
NEAR-SURFACE INVERSION IN PLACE, EFFECTIVE SHEAR IS ESTIMATED TO BE
NEAR 40 KNOTS. THIS COULD SUPPORT AN ISOLATED AND MARGINAL THREAT
FOR SEVERE WIND GUSTS OVER THE NEXT COUPLE OF HOURS, ESPECIALLY AS
SURFACE TEMPERATURES AHEAD OF THE STORMS BEGIN TO INCREASE.
..BROYLES/SMITH.. 07/20/2026
..PLEASE SEE WWW.SPC.NOAA.GOV FOR GRAPHIC PRODUCT
ATTN...WFO...DVN...ARX...MPX...DMX...
LAT...LON 43549372 43049385 41999340 41419293 41159252 41039199
41089155 41329112 41759080 42189082 42839106 43439143
43809184 43999228 43979296 43799344 43549372
MOST PROBABLE PEAK WIND GUST...55-70 MPH
MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
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