Mesoscale Discussion 248

Issued

Mar 24, 2021, 11:37 PM CDT (04:37 UTC)

Expired

Mar 25, 2021, 12:30 AM CDT

In force

53 min

Issued by

the Storm Prediction Center

Concerning

Severe potential...watch unlikely

Chance of a watch

20%

The Western Arkansas radar (KSRX), 130 km from the middle of the area, began a volume at 04:37 UTC, the scan nearest the moment this went out.

Open the radar archive at this moment

The archived warnings, watches and discussions in force at that minute are drawn over the scan, this one among them.

333 
ACUS11 KWNS 250437
SWOMCD
SPC MCD 250437 
ARZ000-LAZ000-TXZ000-OKZ000-250530-

Mesoscale Discussion 0248
NWS Storm Prediction Center Norman OK
1137 PM CDT Wed Mar 24 2021

Areas affected...southwestern Arkansas...northeastern Texas...and
southeastern Oklahoma

Concerning...Severe potential...Watch unlikely 

Valid 250437Z - 250530Z

Probability of Watch Issuance...20 percent

SUMMARY...Occasional instances of large hail are expected across the
discussion area for the next few hours.  A WW issuance is not
anticipated for this activity.

DISCUSSION...Persistent, occasionally severe thunderstorms have
resulted in reports of 1-1.75 inch diameter hail in southwest
Arkansas recently, and newer convection is developing near the
Arkadelphia area.  Additional convection is also migrating eastward
into the discussion area from southeastern Oklahoma and northeastern
Texas.  The storms are in an environment characterized by relatively
weak instability - especially north of a warm front extending from
near Hugo to Arkadelphia and Monticello.  However, forcing for
ascent associated with increasing low-level flow (around 850 mb) and
fairly steep lapse rates (ranging from 7.5-8 deg C/km based on point
forecast soundings) are supporting occasional hail formation
especially within updrafts that can obtain rotation aloft.  This
general regime should continue over the course of the next few
hours, with convection continuing to spread northeastward - perhaps
toward central Arkansas and vicinity.  The overall regime does not
merit a WW issuance due to the sporadic nature of the hail threat. 
If convection can become rooted nearer the surface, a wind/brief
tornado threat would emerge, although this scenario is in doubt.

..Cook/Grams.. 03/25/2021

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

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

LAT...LON   34879525 35079457 35239361 35139262 34679174 34229183
            33619199 33219270 33009357 33029468 33299536 33599599
            34039612 34329595 34879525

Mesoscale Discussions in Arkansas, 2021Mesoscale Discussions in Texas, 2021Mesoscale Discussions in Oklahoma, 2021Every mesoscale discussion in 2021

The product and its follow-ups from the Iowa Environmental Mesonet's archive of National Weather Service and Storm Prediction Center text; the sounding from the Mesonet's radiosonde archive; radar from the NEXRAD Level II archive.