|Mesoscale Discussion 1382|
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Mesoscale Discussion 1382
NWS Storm Prediction Center Norman OK
0343 PM CDT Fri Jul 21 2017
Areas affected...Central Nebraska...northwest Kansas
Concerning...Severe potential...Watch unlikely
Valid 212043Z - 212215Z
Probability of Watch Issuance...20 percent
SUMMARY...Thunderstorms are expected to develop the remainder of
this afternoon and continue into the evening hours. Isolated
instances of damaging winds and perhaps hail can be expected. A
watch is not anticipated due to the isolated nature of the threat.
DISCUSSION...Towering cumulus clouds were increasing in vertical
extent in the vicinity of a surface trough across northeast through
central Nebraska at 2030Z, and a small area of thunderstorms has
developed across northwest Kansas. Intense diurnal heating of a
moist (PW values of 1.5 to 1.9 inches) air mass has resulted in
strong surface-based instability with MLCAPE of 3000-4000 j/kg.
Modest westerly mid-level flow has contributed to effective shear of
20-35 kts, sufficient for some degree of organization, including
isolated supercell structures given the degree of instability.
Water loading in updrafts and strong DCAPE will promote a risk for
damaging gusts with the strongest storms through early evening, and
a few instances of hail will also be possible. Overall risk appears
to be relatively confined in space and time, and a watch is not
...Please see www.spc.noaa.gov for graphic product...
LAT...LON 40049903 39730048 39780104 40450066 40940023 41250014
41590001 41859997 42109964 42239889 42279843 42279812
42109781 41769753 41139758 40329794 40049903
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