SPC MD 545



MD 0545 CONCERNING SEVERE THUNDERSTORM WATCH 131… FOR SOUTHEASTERN NEBRASKA AND NORTHEAST KANSAS.

MD 0545 Image

Mesoscale Discussion 0545
NWS Storm Prediction Center Norman OK
0501 PM CDT Sun May 05 2019

Areas affected...Southeastern Nebraska and northeast Kansas.

Concerning...Severe Thunderstorm Watch 131...

Valid 052201Z - 052330Z

The severe weather threat for Severe Thunderstorm Watch 131
continues.

SUMMARY...A cluster of supercells in southeastern Nebraska are
producing large to potentially very large hail. This threat is
expected to continue into the evening as these storms drift
southward along a slow moving cold front.

DISCUSSION...Several supercells in southeast Nebraska have been
producing large hail for the past few hours. The westernmost
supercell in Hamilton county Nebraska has produced multiple golf
ball sized hail reports and latest MESH trends suggest hail in
excess of 2 inches may be possible. Expect the westernmost storm in
this cluster to continue to pose the greatest severe threat due to
the higher instability (2000 J/kg MLCAPE per RAP mesoanalysis).
Current effective shear is around 30 to 35 knots per RAP
mesoanalysis and UEX/OAX VWP, however, mid-level winds are expected
to increase through the evening which will further support supercell
organization. In addition, a low-level jet is expected to increase
somewhat during the late evening and early overnight hours which,
combined with maintenance due to the dynamic pressure perturbations
of the rotating updrafts, will support a severe threat continuing
after dark, possibly into northeast Kansas. 

Additional storm development is possible along the cold front in
western portions of watch 131. Cumulus have become more numerous
along the line in the last hour and low-level moisture advection
into this area will lead to continued destabilization along the
boundary. 

Very steep mid-level lapse rates (9.3 C/km per 12Z LBF RAOB) will
continue to support very large hail with the strongest updrafts,
especially in the western half of watch 131 where destabilization is
greatest.

..Bentley.. 05/05/2019

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

ATTN...WFO...EAX...OAX...TOP...GID...GLD...

LAT...LON   41249859 41409797 41449722 41409663 41259593 40639574
            40049548 39769566 39649710 39789846 39889904 39889958
            39919986 40059995 40349997 40809937 41249859 

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