SPC Mar 19, 2025 0100 UTC Day 1 Convective Outlook

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0756 PM CDT Tue Mar 18 2025

Valid 190100Z - 191200Z

...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM NORTHEAST
KANSAS TO FAR EASTERN IOWA...

...SUMMARY...
Isolated, marginally severe hail is possible by late tonight in a
corridor from north central Kansas through central Iowa.

...Discussion...
00Z Surface analysis shows a 989mb surface low in west-central
Kansas this evening. Ahead of this surface low, a low-level jet is
strengthening (now 50 kts below 1km on the KICT VWP). This low-level
jet is forecast to strengthen to 65 to 70 knots by 06Z which will be
crucial for low-level moistening and thunderstorm potential later
tonight. The 00Z RAOB from TOP showed a very dry profile. However,
slightly better moisture is in place across central Oklahoma with a
8C dewpoint at 850mb at OUN. Forecast guidance continues to indicate
that enough of this moisture will advect north into warm frontal
zone across northeast Kansas and Iowa for weak to moderate
instability by 08-10Z. If sufficient moistening occurs for 1000 J/kg
MUCAPE early Wednesday morning, supercells capable of large hail
will be possible given 40-45 knots of effective shear. 

Expanded the marginal slightly east this outlook to account for
latest HRRR placement of the strongest storms early Wednesday
morning.

..Bentley.. 03/19/2025

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