971
FXUS63 KDTX 111946
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
346 PM EDT Fri Jul 11 2025

.KEY MESSAGES...

- Chance of thunderstorms remains this afternoon and evening as a
warm front lifts through the region.

- Increasing potential for showers and thunderstorms Saturday which
could produce isolated severe storms and localized heavy rainfall.

- Warmer summertime pattern underway which will continue into next
week today, continuing through midweek as humidity rises and heat
indices hover around 90.

- Drier weather expected Sunday through midweek as high pressure
moves over the area.

&&

.DISCUSSION...

Remnants of last nights elevated MCV still working through SE MI
this afternoon with a bit of an uptick in convection as the surface
warm front lifts up through the region. There is still a chance to
build some instability once this moves through this evening but
chances decrease as subsidence in the wake of the MCV should help
minimize coverage of new development. We`ll keep the current chance
pop going as the clearing upstream is already allowing a bubble of
SBCAPE in excess of 2000 J/kg to build and the nose of the 850mb low
level starts pushing into SW lower. Shear will remain fairly weak,
around 20 knots, so storms should struggle to get too organized but
an isolated storm or two may become strong to severe. Damaging
downbursts winds would be the biggest threat with heavy downpours
also a concern as dewpoints are rising into the 70s behind the
lifting warm front and PWATs are up around 1.75 inches. We remain in
a Marginal Risk for severe weather today.

Better chance for strong to severe storms comes Saturday as a
northern stream trough moves into the Midwest and pulls the stalled
shortwave over IA rapidly northeastward tonight through the northern
Great Lakes with the trailing cold front draped just west of Lake
MI. This puts us solidly in the warm sector tonight into Saturday
with southwesterly flow through that time. There will be a chance of
isolated showers/storms tonight with highest chance up across Mid MI
with a leading edge of the theta e gradient. Rest of SE MI should be
fairly quiet.

On Saturday there is a Slight Risk of severe weather per SPCDY2. The
main trough axis approaches toward morning with the increasing low
level jet pushing a weak shortwave up through SW MI which in turn
pulls up a secondary warm front/theta e surge. Strong WAA will bring
temps to near 90 with dewpoints into the 70s ahead of the cold front
which looks to sweep through the area during peak heating in the
evening. Most CAMs suggest initiation around 18Z with the frontal
line of convection pushing through by about 00Z. SBCAPE will rise to
around 2500 J/kg with shear remaining on the lower side around 25
knots but could reach up to around 30, sufficient to help storms
organize. Wind still looks to be the main threat with these storms,
with hail and heavy rain additional threats. Still cannot rule out a
tornadic threat with the warm fronts in the area.

Quieter weather to end the weekend Sunday as mid level trough lies
over the region and high pressure starts building in. Cold front
could get hung up over far eastern lower MI which could spark a few
showers Sunday, but most of SE MI will remain dry. Nearly zonal flow
with a slight broad mid level ridge builds over the region to start
the week with the next chance of storms targeting the area on
Wednesday as the next trough arrives.

&&

.MARINE...

A weak area of high pressure will continue to promote lighter winds
through the remainder of the day. Scattered to numerous showers with
some embedded thunderstorms remain possible through the afternoon
and evening, which brings the chance to see some embedded stronger
wind gusts. Additional chances for showers and thunderstorms will re-
enter Saturday into Sunday ahead of and along a cold front, which
brings additional chances for strong to severe thunderstorm
development capable of producing wind gusts aoa 35 knots. Winds veer
from southeast to southwest through tonight into tomorrow, with
continued veering to the west after the passage of the front. Dry
conditions return in the wake of the front.

&&

.PREV DISCUSSION...
Issued at 1226 PM EDT Fri Jul 11 2025

AVIATION...

Lead surge of moisture and subtle upper level disturbance allowing
for scattered showers/isolated thunderstorms at the present time.
Weak convergence/warm front lifts northward this afternoon, which
could prove sufficient for additional isolated-scattered showers and
thunderstorms developing with the daytime heating/instability.
However, confidence is low in the subsidence wake of the departing
disturbance, but FNT/MBS stand the best chance of activity late
today/this evening. Southeast Michigan then looks to be solidly in
the warm sector tonight with ceiling free skies (under 10 kft)
expected. Low level moisture and instability ramps up tomorrow with
southwest winds increasing, sustained aoa 10 knots with gusts aoa 20
knots by early afternoon. Cold front should be able to trigger a
blossoming coverage of showers and strong thunderstorms in the late
afternoon hours.

For DTW/D21 Convection... Low chance of a thunderstorm impacting the
airport this afternoon/evening. Much higher chance late tomorrow
afternoon.

THRESHOLD PROBABILITIES...

* Low for ceiling 5000 ft or less outside of thunderstorms.

* Low for thunderstorms, except medium late tomorrow afternoon.


&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&

$$

DISCUSSION...DRK
MARINE.......AM
AVIATION.....SF


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