ZCZC SPCSWOMCD ALL
ACUS11 KWNS 262236 
SPC MCD 262236 
IAZ000-MOZ000-KSZ000-NEZ000-270000-

Mesoscale Discussion 0534
NWS Storm Prediction Center Norman OK
0536 PM CDT Fri Apr 26 2024

Areas affected...Mid Missouri Valley

Concerning...Tornado Watch 140...142...

Valid 262236Z - 270000Z

The severe weather threat for Tornado Watch 140, 142 continues.

SUMMARY...Supercells, and attendant severe threat, will spread
northeast across western IA/northwest MO.

DISCUSSION...Exit region of mid-level jet is spreading northeast
ahead of ejecting short-wave trough. Boundary-layer air mass is
stubbornly recovering across central IA where mid 50s surface dew
points persist. Partial clearing across southwestern IA has
contributed to surface temperatures warming into the lower 70s, and
lower 60s dew points have now advanced into Crawford/Audubon County.
Forecast soundings suggest 60F dew points are needed for
surface-based buoyancy and additional recovery is expected into
central IA later this evening.

Around a half dozen well-defined, long-lived supercells are now
advancing east of the MO River into western IA. Per 60F dew points,
air mass immediately downstream is adequately buoyant for
maintaining robust updrafts. Tornado threat continues until updrafts
encounter cooler conditions farther downstream.

..Darrow.. 04/26/2024

...Please see www.spc.noaa.gov for graphic product...

ATTN...WFO...DMX...EAX...FSD...OAX...TOP...

LAT...LON   42589550 42329451 40819410 39869514 40099577 41079581
            41769625 42589550 

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