414
AWUS01 KWNH 130057
FFGMPD
NMZ000-AZZ000-CAZ000-130500-

Mesoscale Precipitation Discussion 1266
NWS Weather Prediction Center College Park MD
855 PM EDT Sat Sep 12 2026

Areas affected...Central and Southern AZ...West-Central NM

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

Valid 130055Z - 130500Z

SUMMARY...A few more hours of scattered showers and thunderstorms
with locally high rainfall rates may support an additional
isolated concern for some flash flooding.

DISCUSSION...The late-day GOES-W IR satellite imagery still shows
some scattered areas of showers and thunderstorms across portions
of central and southern AZ along with west-central NM. The
activity has generally peaked, and overall the cloud tops are
generally warming as instability has been exhausted through the
convective overturning process.

The instability that still remains somewhat formidable based on
the latest RAP analysis is mainly confined to areas of southwest
to south-central AZ where SBCAPE values remain as high as 2000+
J/kg. However, there are multiple outflow boundaries sweeping
across the region which are actively working to weaken the surface
instability profile.

Regardless, the remaining footprint of locally colliding outflow
boundaries and presence of orographics will continue to support at
least a few more hours of scattered areas of monsoonal shower and
thunderstorm activity. PWs remain anomalously high across the
region with values of 2 to 3 standard deviations above normal, and
therefore, any additional convection this evening will still be
capable of producing high rainfall rates of up to 1.5 inches/hour.

Where any cells still try to hang up near areas of higher terrain
or along colliding mesoscale/outflow boundaries, there may be some
additional spotty 2+ inch amounts. This may yield another instance
or two of flash flooding, and more likely that this would be an
impact to some of the normally dry washes, although a highly
localized urban impact or perhaps a burn scar issue could also
still be possible from these additional rains in the near-term.

Orrison

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

ATTN...WFO...ABQ...FGZ...PSR...TWC...VEF...

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

LAT...LON   35821178 35181023 35160859 34700771 34020770
            33430868 32731066 31691190 31761313 32321406
            33021451 33971440 34501373 35411309