Severe Storm Outlook Narrative (AC)
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000
ACUS11 KWNS 182002
SWOMCD
SPC MCD 182001
ARZ000-MOZ000-TXZ000-OKZ000-182200-

Mesoscale Discussion 0482
NWS Storm Prediction Center Norman OK
0301 PM CDT Thu Apr 18 2024

Areas affected...eastern Oklahoma and western Arkansas

Concerning...Severe potential...Watch possible

Valid 182001Z - 182200Z

Probability of Watch Issuance...60 percent

SUMMARY...Isolated to widely scattered supercells are possible this
afternoon/evening.

DISCUSSION...A strong cold front continues to move rapidly across
Oklahoma this afternoon. Temperatures ahead of the front have warmed
into the upper 70s to near 80 across eastern Oklahoma with a moist
airmass featuring dewpoints in the upper 60s to low 70s. This yields
over 2500 J/kg MLCAPE and effective shear around 40 to 45 knots.
This parameter space is quite favorable for supercells capable of
large to very large hail if storms form. However, there is
considerable uncertainty regarding convective coverage this
afternoon/evening. Despite strong convergence along the front in
northeast Oklahoma, updrafts have struggled to deepen sufficiently
to produce lightning. KINX base reflectivity indicates this is most
likely due to storms struggling to stay anchored to, or ahead of,
the cold front in the warm air. Stronger mid-level flow, the arrival
of which likely coincides with mid-upper level cirrus moving across
western Oklahoma now, may assist in storms remaining along or ahead
of the front later this afternoon. Therefore, anticipate storms may
struggle for the next 1 to 2 hours before a better chance of a few
strong to severe supercells occurs later this afternoon/evening with
the arrival of this mid-level speed max.

..Bentley/Mosier.. 04/18/2024

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

ATTN...WFO...LZK...SGF...SHV...TSA...FWD...OUN...

LAT...LON   36209306 35319317 34159382 33649456 33789532 33909642
            34319669 34989611 35799563 36569507 36489303 36209306
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