|Mesoscale Discussion 1228|
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Mesoscale Discussion 1228
NWS Storm Prediction Center Norman OK
1251 AM CDT Tue Jul 04 2017
Areas affected...Southeast OK...Far NE Texas...Western and Central
Concerning...Severe Thunderstorm Watch 394...
Valid 040551Z - 040745Z
The severe weather threat for Severe Thunderstorm Watch 394
SUMMARY...An isolated wind damage threat is expected to decrease
over the next couple of hours as a convective line moves eastward
into western Arkansas. Weather watch issuance should not be needed
to the east of WW 394.
DISCUSSION...The latest radar imagery shows a linear MCS moving
through eastern Oklahoma. Although satellite shows warming tops with
the linear MCS, the convective line is being supported by a southern
Plains shortwave trough evident on water-vapor imagery. Surface
analysis shows a moist airmass ahead of the line with surface
dewpoints in the lower to mid 70s F. This is resulting in moderate
instability across far eastern Oklahoma and western Arkansas. This
should enable the line to remain intact over the next couple of
hours. However, the WSR-88D VWPs at Fort Smith, AR and Little Rock,
AR suggest that deep-layer shear weakens with eastward extent. This
along with dropping surface temperatures should result in a gradual
weakening of the MCS over the next hour or two.
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 36109525 35459539 34889575 34389642 33939649 33449544
33269450 33469327 33899254 34699233 35689249 35989389
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