Subj : MESO: Nws Weather Prediction Center College Park Md
To   : wx-storm@lists.illinois.edu
From : COD Weather Processor
Date : Tue Aug 06 2024 23:28:38

AWUS01 KWNH 062328
FFGMPD
AZZ000-070430-

Mesoscale Precipitation Discussion 0824
NWS Weather Prediction Center College Park MD
728 PM EDT Tue Aug 06 2024

Areas affected...Southern Arizona...

Concerning...Heavy rainfall...Flash flooding possible

Valid 062330Z - 070430Z

SUMMARY...Strengthening scattered thunderstorms with increasing
rainfall efficiency and potential for downstream collisions
suggest widely scattered localized flash flooding may be possible
tonight.

DISCUSSION...GOES-E WV suite depicts a compact TUTT cell
retrograding slowly across the US/Mexico border around 109W,
providing favorable DPVA aloft with a favorable northeasterly 3H
jet streak (30kts) across central AZ supporting favorable outflow
to any developing thunderstorms.  Deep layer moisture and higher
theta-E air mass continues to pool over the low Deserts and as
banked up against the higher terrain of E Pinal and Cochise
counties reaching total values up to 1.25" (while having deeper
and much higher Tds into the 60s over W Pima/Yuma county, reaching
as much as 1.75").  Additionally, with Tds into the 60s as far
east as 110W, there are favorable MLCAPEs values of up to 1500
J/kg that have become generally uncapped over the last few hours.=20
As such, scattered CBs have developed in the vicinity of I-8
between Marana and into Santa Cruz county.  Moisture convergence
into the cells is sufficient to support 1-1.5"/hr rates (higher
instantaneous rates).  Further expansion and intensification is
expected based on Hi-Res CAMs, including the UA WRF.  This leads
to the potential for merging cells or outflow boundary collisions
that would broaden overall updraft width/slab ascent.  Given much
of this would fall over hydrophobic (either urban or hard-pan
desert), rapid runoff may result in localized flash flooding
conditions across the area of concern.  However, cells will slowly
diminish with loss of heating after dark, with remaining cells
forming on those colliding old outflow boundaries.=20

Gallina

....Please see https://urldefense.com/v3/__http://www.wpc.ncep.noaa.gov__;!!=
DZ3fjg!4UoWWWO2AzbjqDSnTwChf8czZ8itmTpMwZFNELeD7HPB52Ru2pN59bHs6SwtYr8cpoQs=
m9yhE50EWMqDmTpM9ONRtt4$  for graphic product...

ATTN...WFO...PSR...TWC...

ATTN...RFC...CBRFC...NWC...

LAT...LON   33211060 32901040 32211012 31540995 31221014=20
            31191103 31621240 31991337 32251368 32681347=20
            33041211 33191125=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 3.20-Linux
 * Origin: capitolcityonline.net * Telnet/SSH:2022/HTTP (1:2320/105)

.