Mesoscale Discussion 1860
NWS Storm Prediction Center Norman OK
1035 PM CDT Fri Aug 07 2026

Areas affected...Parts of southeast AZ

Concerning...Severe potential...Watch unlikely 

Valid 080335Z - 080530Z

Probability of Watch Issuance...5 percent

SUMMARY...Strong to locally severe gusts are possible into late
evening.

DISCUSSION...Some increase in storm coverage and intensity has been
noted within the last hour to the northeast of Tucson, with cooling
cloud tops noted on IR imagery. This uptick has occurred as
southwesterly moving outflow interacts with local terrain features
and moderate buoyancy. With increasing CINH downstream of this
convection, the magnitude and longevity of any severe threat remains
uncertain. However, weak northeasterly steering flow will allow
outflow to continue spreading southwestward. In the presence of a
remnant well-mixed boundary layer and steep low-level lapse rates,
potential for strong to locally severe gusts may continue into the
late evening, even if deep convection begins to weaken with time.

..Dean/Mosier.. 08/08/2026

...Please see www.spc.noaa.gov for graphic product...

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

LAT...LON   31821020 31701096 31961163 32721206 33001179 33011101
            32711007 32400987 32110987 31890993 31821020 

MOST PROBABLE PEAK WIND GUST...55-70 MPH

Day 1 Convective Outlook  
NWS Storm Prediction Center Norman OK
0745 PM CDT Fri Aug 07 2026

Valid 080100Z - 081200Z

...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF
SOUTHERN IOWA...AND THE UPPER GREAT LAKES...

...SUMMARY...
Isolated severe thunderstorms remain possible across parts of the
Upper Midwest/Great Lakes this evening, with large hail and severe
winds the main threats. The severe risk should gradually decrease
through 05z (midnight local time).

...Iowa into northern Wisconsin/U.P. of Michigan...

Isolated strong to severe thunderstorms continue this evening across
parts of IA and the U.P. of MI ahead of a surface cold front. Some
additional re-development may occur along the front across
central/southern IA over the next few hours, while convection
further north gradually decreases in intensity over the next couple
of hours. Isolated large hail and strong/locally damaging wind gusts
remain possible. Reference MCD 1857 for more information. 

Further south, severe probabilities were trimmed across portions of
the MO Valley, where thunderstorm potential appears limited
overnight. 

...AZ/NM into the TX Panhandle...

Isolated strong to severe thunderstorms will persist for a few more
hours across parts of eastern NM into the TX Panhandle and far
west-central OK. Severe wind gusts will be the main hazards with
this activity given the hot, well-mixed boundary layer. Some of the
stronger storms could sporadically produce large hail. Overall
severe risk should gradually wane with loss of daytime heating after
03z. 

Further southwest, isolated thunderstorms moving off higher terrain
into portions of southern AZ and southwest NM will pose a risk for
strong wind gusts the next few hours. Storm coverage currently is
fairly sparse, and it is uncertain if sufficient clustering will
occur and spread west/southwest into lower elevations. Given
uncertainty, will maintain the Marginal (level 1 of 5) risk. 

...Ozark Plateau...

Widely scattered thunderstorms will continue for a few more hours
this evening within the moderately unstable environment. Locally
damaging wind gusts will be possible, but thunderstorm intensity
should gradually wane over the next 1-3 hours. Reference MCD 1858
for more information.

...SD/NE...

A conditional large hail risk remains late tonight/early Saturday
across parts of southern SD into northern NE. Forecast guidance
still suggests isolated elevated thunderstorms will develop within a
corridor of favorable elevated instability and 35+ kt effective
shear magnitudes. If storms develop, large hail will be possible. 

...OH Valley into the Mid-Atlantic...

Locally gusty winds may continue another hour or two with a
thunderstorm cluster of WV and another cluster in CT. Thunderstorm
activity may persist across parts of the Midwest toward the
Mid-Atlantic beyond 02-03z, but overall severe potential is expected
to largely be diminished by then due to loss of daytime and
increasing boundary layer stabilization.

..Leitman.. 08/08/2026