Mesoscale Discussion 1611
NWS Storm Prediction Center Norman OK
0254 PM CDT Mon Jul 13 2026
Areas affected...parts of southeastern through central Arizona
Concerning...Severe potential...Watch unlikely
Valid 131954Z - 132230Z
Probability of Watch Issuance...5 percent
SUMMARY...Widely scattered to scattered intensifying thunderstorms
are increasingly probable by 3-5 PM MST, accompanied by a few
strong, but generally localized, downbursts.
DISCUSSION...A modestly deep-mixed boundary layer is evolving, with
continued daytime heating. Surface temperature/dew point spreads
are increasing in excess of 30-35 degrees F, as temperatures warm
through the 90s. Latest objective analysis suggests that this
environment is also becoming characterized by modest instability,
with CAPE now on the order of 1000 J/kg across the deserts around
Tucson, northwestward toward the Greater Phoenix vicinity.
In response to this destabilization, deepening convection is evident
across the higher terrain of southeastern Arizona, as well as along
the Mogollon Rim vicinity, beneath 10-15 kt southeasterly deep-layer
mean flow. Over the next few hours, scattered thunderstorms appear
likely to continue to initiate and gradually intensify while
propagating northwestward across southeastern into central Arizona.
As it does, the most vigorous cells will pose increasing potential
to produce generally localized strong downbursts during the peak
late afternoon heating.
It is possible that orographic forcing near the Rim could support a
bit more notable upscale growth or clustering of convection, but
steering flow may not support much, if any, propagation and
intensification away from the higher terrain.
..Kerr.. 07/13/2026
...Please see www.spc.noaa.gov for graphic product...
ATTN...WFO...TWC...FGZ...PSR...
LAT...LON 34551179 33491015 32770954 31550936 31411065 32051108
33531243 34031246 34551179
MOST PROBABLE PEAK WIND GUST...55-70 MPH
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