SPC Jun 18, 2025 1630 UTC Day 1 Convective Outlook

SPC 1630Z Day 1 Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
1119 AM CDT Wed Jun 18 2025

Valid 181630Z - 191200Z

...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON
AND EVENING FROM SOUTHEAST MISSOURI EASTWARD ACROSS MUCH OF
ILLINOIS/INDIANA...WESTERN OHIO...AND NORTHERN KENTUCKY...

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PORTIONS OF
THE MID-ATLANTIC REGION...

...SUMMARY...
Severe thunderstorms are expected this afternoon and evening from
parts of southeast Missouri northeastward to the southern Great
Lakes. Scattered to numerous damaging winds, isolated large hail,
and tornadoes all appear possible. Severe thunderstorms with
damaging winds may also develop across parts of the Mid-Atlantic.

...Midwest...
A well-defined shortwave trough is currently over western MO,
tracking rapidly eastward.  At the surface, a low is centered over
northeast MO, with a very moist/unstable air mass in place across
much of IL/IN.  As large-scale forcing for ascent and strengthening
wind fields overspread the unstable warm sector, supercell
thunderstorms are expected to rapidly develop.  All severe hazards,
including a few tornadoes, appear possible through the afternoon as
storms track rapidly northeastward across IL into central/northern
IN.  Refer to MCD #1345 for further details.  Congealing outflow may
eventually lead to a greater damaging wind threat as storms spread
into lower MI and northern OH.

To the southeast of this early thunderstorm scenario, another zone
of convective initiation is expected from southeast MO into parts of
KY/southern IN.  These storms are more likely to grow upscale by
early evening, with a risk of damaging winds spreading into southern
OH and central KY.  Have expanded the ENH slightly eastward to
better cover this area.

...Mid Atlantic...
Visible satellite imagery shows mostly clear skies and strong
heating occurring over northern/central VA, where a hot/humid
airmass is present.  Thunderstorms are expected to develop off the
terrain this afternoon and spread eastward into the DelMarVa region.
 Sufficient flow aloft and steep low-level lapse rates will promote
a risk of strong storms capable wind damage.  Isolated strong storms
may also affect south-central VA and northern NC later this
afternoon as well. Refer to MCD #1344 for further details.

..Hart/Wendt.. 06/18/2025

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