MD 0555 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF CENTRAL AND EASTERN WYOMING INTO WESTERN NEBRASKA AND SOUTH DAKOTA
Mesoscale Discussion 0555
NWS Storm Prediction Center Norman OK
0546 PM CDT Tue Apr 18 2023
Areas affected...portions of central and eastern Wyoming into
western Nebraska and South Dakota
Concerning...Severe potential...Watch unlikely
Valid 182246Z - 190115Z
Probability of Watch Issuance...20 percent
SUMMARY...A few severe gusts are possible through the remainder of
the evening. The severe threat is expected to remain isolated and a
WW issuance is not expected.
DISCUSSION...A surface low continues to intensify across the central
High Plains as a mid-level trough impinges on the central U.S. from
the Rockies. A mid-level impulse is approaching the northern Plains
from central WY, which should support convective intensification
through the remainder of the evening into early overnight across
portions of eastern WY into western SD/NE. Strongly forced,
low-topped convection will develop and intensify atop a relatively
dry boundary layer extending up to 700 mb. Though overall buoyancy
is scant, the dry boundary layer consists of steep low-level lapse
rates (i.e. 8-9 C/km per 22Z mesoanalysis) which could foster
efficient downward momentum transport in the stronger storms to
support damaging gusts. Nonetheless, the severe threat is expected
to remain isolated and a WW issuance is not expected.
..Squitieri/Edwards.. 04/18/2023
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...LBF...UNR...CYS...RIW...
LAT...LON 43250817 44080661 44650502 44820381 44740245 44600196
44240159 43530151 42760167 42110198 41880221 41750280
41700371 41500518 41450637 41770750 43250817
