Subj : MESO: Mesoscale Discussion 1644
To   : wx-storm@lists.illinois.edu
From : COD Weather Processor
Date : Thu Jul 20 2023 18:16:10

ACUS11 KWNS 201816
SWOMCD
SPC MCD 201815=20
COZ000-NEZ000-NMZ000-WYZ000-202015-

Mesoscale Discussion 1644
NWS Storm Prediction Center Norman OK
0115 PM CDT Thu Jul 20 2023

Areas affected...Southeast WY...far southwest NE...eastern/central
CO...and far northeast NM

Concerning...Severe potential...Watch likely=20

Valid 201815Z - 202015Z

Probability of Watch Issuance...95 percent

SUMMARY...Severe thunderstorms capable of very large hail, severe
winds, and possibly a couple tornadoes are expected this afternoon
into the evening. A watch is likely for parts of the area in the
next 1-2 hours.

DISCUSSION...Latest water vapor imagery depicts a convectively
augmented midlevel impulse advancing eastward across southern WY --
in the wake of an MCV moving eastward into southwestern NE.
Continued heating along the high terrain from southern WY southward
into northern NM, combined with moist east-southeasterly upslope
flow (upper 50s/lower 60s dewpoints), will support increasing
convective development during the next couple of hours. Additional
convective development is possible along east/west-oriented remnant
outflow and differential heating boundaries intersecting the
Rockies.

40 kt midlevel westerlies (sampled by regional VWP) atop sheltered
east/southeasterly low-level flow will yield around 50 kt of
effective shear -- supportive of supercell development. The primary
concerns with initial storm development will be very large hail and
severe gusts, though a tornado or two cannot be entirely ruled out
given rich boundary-layer moisture/deep-effective inflow layers and
modest clockwise low-level hodograph curvature (around 200 m2/s2 0-1
km SRH) sampled by the KFTG VWP.=20

With time, storms should increase in coverage with
east-southeastward extent as a plume of weak warm-air advection
overspreads the rich low-level moisture across eastern CO -- in
response to the approaching midlevel impulse. While a corresponding
increase in low-level hodograph curvature will conditionally favor a
couple of tornadoes (especially in the vicinity of the
aforementioned boundaries), numerous storms and related cell
interactions cast uncertainty on the overall risk. Nevertheless,
severe winds and large hail are expected with
east-southeastward-moving supercells and organized clusters. A watch
will likely be issued in the next hour or two for parts of the area.

...Weinman/Hart.. 07/20/2023

....Please see https://urldefense.com/v3/__http://www.spc.noaa.gov__;!!DZ3fj=
g!8pLvsEdJnlc_PBJMUyQeLh66dvNEIpkdvSwmdtaJObehUkSnp55Ps8P6gIwztwIzI5c9xw_gQ=
Lgd7gfxHpTSnt1jQbs$  for graphic product...

ATTN...WFO...GLD...PUB...BOU...CYS...ABQ...

LAT...LON   38810517 40090531 41140534 41460516 41600481 41620456
            41510414 41250366 40740295 40460262 39890239 39020242
            38110263 37440281 37120299 36910328 36810416 36860475
            36950496 37210507 38810517=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)

.