131
AWUS01 KWNH 110302
FFGMPD
COZ000-NMZ000-AZZ000-UTZ000-NVZ000-CAZ000-110800-

Mesoscale Precipitation Discussion 0858
NWS Weather Prediction Center College Park MD
1101 PM EDT Sat Aug 10 2024

Areas affected...Portions of the Southwest U.S.

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

Valid 110300Z - 110800Z

SUMMARY...Heavy showers and thunderstorms will continue to persist
for a few more hours across portions of the Southwest U.S. Some
additional pockets of flash flooding will be possible.

DISCUSSION...The evening GOES-E IR satellite imagery shows
scattered to broken coverage of showers and thunderstorms
continuing across areas of especially western and northern AZ and
into areas of south-central to southeast UT and southwest CO.
Despite increasing low-level CINH with the loss of daytime heating
and convective overturning, SBCAPE values remain as high as 2000
to 2500+ J/kg across areas of western AZ and locally across
south-central to southeast UT.

Multiple colliding outflow boundaries coupled with the remaining
instability and localized orographics should continue to favor the
ongoing convection lingering for another few hours before
gradually weakening. PWs across the region are rather high given
the depth of monsoonal moisture pooled around the western
periphery of the subtropical ridge near the Four Corners region,
and are locally on the order of 1 to 2 standard deviations above
normal.

Some very cold-topped convective cells continue to evolve, and the
rainfall rates with these remaining stronger storms may still
reach 1 to 2 inches/hour. Slow cell-motions and interaction with
the terrain locally may yield some additional totals that reach 2
to 2.5 inches. Some additional instances of flash flooding will be
possible, and especially over any of the sensitive slot canyons
and localized burn scar locations.

Orrison

...Please see www.wpc.ncep.noaa.gov for graphic product...

ATTN...WFO...ABQ...FGZ...GJT...PSR...SLC...VEF...

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

LAT...LON   38180783 37120736 35660961 34461061 33461199
            33081396 33681506 34901512 36021459 37211307
            37981053