Mesoscale Discussion 0322
NWS Storm Prediction Center Norman OK
1253 PM CDT Sat Apr 13 2019
Areas affected...Northeast Louisiana into southwest/west central
Mississippi
Concerning...Severe potential...Watch possible
Valid 131753Z - 132000Z
Probability of Watch Issuance...60 percent
SUMMARY...Thunderstorms are expected to continue to initiate across
the region through the afternoon. Some of these may be accompanied
by a risk for severe hail through mid afternoon, before the
potential for tornadoes increases closer to 3-4 PM CDT, when the
issuance of a watch currently appears most likely.
DISCUSSION...Vigorous thunderstorm development, largely supported by
strengthening low-level warm advection above/to the cool side of a
northward advancing surface front, is now underway as far east as
the Monroe LA vicinity, where a 4-5 mb 2 hour surface pressure fall
maximum has spread within the last hour. In the presence of
moderately large CAPE and strong cloud-bearing layer shear, this
activity may continue to pose a severe hail risk through mid
afternoon.
Gradually, as the front progresses northward, it appears that a
warming and moistening boundary layer (including surface dew points
increasing to near 70f) may become supportive of intensifying
boundary-layer based storm development closer to the 21-22Z time.
Models suggest that this will also coincide with enlarging low-level
hodographs beneath an 850 mb jet strengthening to 50+ kt, which is
expected to support increasing potential for tornadoes, a few of
which may become strong.
..Kerr/Grams.. 04/13/2019
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...JAN...
LAT...LON 33139141 33538979 32798943 32468946 31789007 31649080
31679147 32579188 33139141
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