ACUS11 KWNS 251850
SWOMCD
SPC MCD 251849=20
NDZ000-MTZ000-WYZ000-252045-

Mesoscale Discussion 0864
NWS Storm Prediction Center Norman OK
0149 PM CDT Thu May 25 2023

Areas affected...portions of southern and eastern Montana and far
northwestern Wyoming.

Concerning...Severe potential...Watch unlikely=20

Valid 251849Z - 252045Z

Probability of Watch Issuance...20 percent

SUMMARY...Isolated strong to severe storms should develop and move
off the higher terrain this afternoon. A few instances of damaging
winds and marginally severe hail are possible with the strongest
storms. Uncertainty on the coverage of severe weather is high,
suggesting the probability of a Weather Watch is low.

DISCUSSION...As of 1840 UTC, regional satellite analysis showed
deepening cumulus towers and incipient thunderstorms developing
across the higher terrain in parts of southern MT and northern WY.
Along the eastern edge of a broad upper-level low over the Northwest
and northern Rockies, weak synoptic forcing for ascent, diurnal
heating and terrain circulations should allow for scattered
thunderstorm development this afternoon. Sufficient surface moisture
(surface dewpoints in the mid to upper 50s) in combination with
modestly steep mid-level lapse rates near 7 C/km are support
500-1000 J/kg of MLCAPE from SPC mesoanalysis. As updrafts mature,
modest mid-level flow east of the upper low will allow for some
storm organization with 25-35 kt of effective shear present.
Multi-cell clusters and perhaps transient supercell structures are
possible this afternoon/evening. The strongest storms may pose a
risk for isolated strong wind gusts and perhaps marginally severe
hail given enhanced flow aloft. However, the lack of broader
synoptic support for organized storms suggests the severe threat
will likely remain isolated, and a Weather Watch is unlikely.

..Lyons/Hart.. 05/25/2023

...Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj= g!-2KyTLaNvCr4tkA7P3BjzwKtabsMuQrD0dCra3RkAtfZ_bdsLJ_JfiALPEsyKF-PdtcfDObIG= OdCCj8jYQnriU9yDMI$ for graphic product...

ATTN...WFO...BIS...BYZ...GGW...RIW...TFX...MSO...

LAT...LON 49000690 49040413 48590373 45370421 44730866 44621076
45341194 45751236 46351183 47181042 49000690=20


=3D =3D =3D
To unsubscribe from WX-STORM and you already have a login, go to https://lists.illinois.edu and use the "Unsubscribe" link. Otherwise email Chris Novy at cnovy@cox.net and ask to be removed from WX-STORM.

--- SBBSecho 3.14-Linux
* Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)