MD 1166 CONCERNING SEVERE POTENTIAL…WATCH UNLIKELY FOR PORTIONS OF SOUTH-CENTRAL MT
Mesoscale Discussion 1166 NWS Storm Prediction Center Norman OK 0210 PM CDT Thu Jul 26 2018 Areas affected...Portions of south-central MT Concerning...Severe potential...Watch unlikely Valid 261910Z - 262145Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorms capable of severe hail and severe wind gusts will evolve through the area this afternoon but are expected to be isolated enough to preclude a Watch. DISCUSSION...A subtle perturbation in relatively moist mid-to-upper level flow rounding the top of the western ridge, sufficient mid-level lapse rates, and surface heating within low 50s dewpoints has contributed to isolated thunderstorms early this afternoon. Continued heating should contribute to further destabilization ahead of the storms moving off the Big Snowy Mountains, as well over the higher elevations to the west and northwest of there. An additional storm or two is expected to emerge from the decaying storms currently over Musselshell county as a corridor of increasing MLCAPE and steepening low-level lapse rates becomes established over the area. Effective shear in the 35-45 kt range should allow for supercell structures and severe hail/wind potential as these storms respond to the increasing CAPE. Additional thunderstorms should develop off the Little and Big Belt Mountains to the north and west into the Glacier National Park area, where a similar environment will also support a severe hail/wind threat. However, given the weak large-scale forcing for ascent and somewhat limited instability, the coverage of storms/severe weather is expected to remain low enough to preclude a Watch, but the area will be monitored throughout the afternoon for signs of a more widespread severe threat. ..Coniglio/Hart.. 07/26/2018 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BYZ...GGW...TFX...MSO... LAT...LON 45130893 45241010 45841194 46961336 47621375 48251393 48791351 48771306 48201179 47500999 47040881 46460782 45870748 45480754 45010773 45120883 45130893
from SPC Mesoscale Discussions http://bit.ly/2OoirNo
Be First to Comment