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AWUS01 KWNH 110156
FFGMPD
NMZ000-AZZ000-UTZ000-NVZ000-CAZ000-110730-

Mesoscale Precipitation Discussion 1001
NWS Weather Prediction Center College Park MD
954 PM EDT Mon Aug 10 2026

Areas affected...Southwest U.S.

Concerning...Heavy rainfall...Flash flooding likely

Valid 110154Z - 110730Z

SUMMARY...Scattered monsoonal showers and thunderstorms will
continue into the evening hours which will likely support some
additional areas of flash flooding.

DISCUSSION...The latest GOES-W IR satellite imagery shows
scattered areas of cold-topped convection continuing to impact the
Southwest U.S., with some of the coldest/deepest convection
occurring over portions of central and southern AZ. MLCAPE values
vary a bit across the region, but are locally as high as 1500 to
2500 J/kg where the atmosphere has not been convectively
overturned yet. This is especially the case across southwest AZ.
Instability is also seen persisting over southeast CA, with a nose
of this aimed up into far southern NV and to a lesser extent
southwest UT.

A couple of MCVs are still in place over far southern NV and
southwest UT, and are generally drifting northward around the
western periphery of the subtropical ridge. They will still be
capable of working in tandem with the leftover instability and
orographics for some additional areas of convection over the next
few hours. However, generally the greatest remaining threat of
convection will be down across central and southern AZ where
elevated instability and as much as 30 to 40 kts of effective bulk
shear will favor convective sustenance and organization through
the remainder of the evening hours.

Rainfall rates with the continuing monsoonal shower and
thunderstorm activity may again be locally as high as 1.5 inches
in as little as 30 minutes. Some storms in radar imagery are also
showing some spotty evidence of backbuilding, and this will only
enhance the hourly rainfall potential. The latest experimental
WoFS guidance suggests additional rainfall totals of 2 to 2.5
inches where these stronger storms in central and southern AZ tend
to persist.

Given the current convective trends, additional areas of flash
flooding will be likely for at least a few more hours, and
especially across areas of central and southern AZ. The threat
will be more isolated across far southern NV and southern UT.

Orrison

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

ATTN...WFO...ABQ...EPZ...FGZ...GJT...PSR...SGX...SLC...TWC...
VEF...

ATTN...RFC...FWR...RSA...STR...NWC...

LAT...LON   38551135 37721034 36490991 35370914 34680870
            34090849 33280845 32560861 31870897 31530937
            31311009 31391153 31871333 32211483 32321599
            32651673 33161697 33761709 34401703 35231682
            36231624 37661484 38501293