111
FXUS63 KDTX 221729
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
129 PM EDT Tue Apr 22 2025

.KEY MESSAGES...

- Cooler Tuesday, but temps back up into the 70s Wednesday-Friday.

- Widespread rain expected to return for Friday.

&&

.AVIATION...

High pressure over the Ohio Valley maintains VFR conditions with
light westerly surface wind backing and weakening tonight. A series
of weak disturbances will bring in mid-level moisture this afternoon
through tonight with ceilings likely to stay above 5000 kft. There
will be a slight chance for showers across the entire area with low
confidence on timing and impact to flight category. The highest
probability exists at MBS where the PROB30 group was maintained late
this evening. Non-zero chance exists for thunder but too unlikely to
include in the TAF. A warm front will migrate over the area on
Wednesday, maintaining the mid-level clouds and low-end chances for
showers and thunderstorms - mainly during the afternoon.

.DTW THRESHOLD PROBABILITIES...

* Low for ceiling at or below 5000 feet tonight and Wednesday.

* Low for thunderstorms Wednesday afternoon.

&&

.PREV DISCUSSION...
Issued at 343 AM EDT Tue Apr 22 2025

DISCUSSION...

Mid week period governed by low amplitude westerly mid level flow,
featuring a series of minor pv features and emergence of a broader
scale warm frontal boundary. High pressure anchored over the Ohio
valley this morning offers a definitive window of dry and stable
conditions under existing mid level subsidence through the daylight
hours today. Low level thermal troughing evident locally this
morning loses influence with time as a moderating thermal profile
capitalizes on full insolation potential. This positions afternoon
temperatures again above average - highs mainly low to mid 60s.
Initial shortwave shears across the region tonight and early
Wednesday. This process dumps a limited supply of mid level moisture
into SE MI, but retains a dry low level profile. Given a rather
disorganized or ill-defined vertical motion field tied to passing
mid level energy, rain shower potential appears limited. There will
be a noted increase in mid level lapse rates, so even a low coverage
could offer a rumble of thunder.

Warm frontal boundary washes northward Wednesday, initiating an more
meaningful warming trend within the background of gradually building
upper heights. Established warm air advection will persist through
Thursday, affording the warmest day this forecast period as highs
peak well into the 70s. Convective shower w/ isolated t-storm
potential remains ill-defined throughout this period, owing to
uncertainty in both placement and magnitude of additional inbound
low amplitude pv, as well as low level frontal positioning and
associated convergence. Forecast will continue to highlight broader
lower end rain chances at times, with further revision likely as near
term detail becomes more evident.

A more dynamic open wave ejecting out of the southern plains will
provide a greater larger scale opportunity for rain Friday.
Collective ensemble guidance generally holds with a progressive
solution overall, confining the impact to mainly the Friday and
Friday night periods ahead of high amplitude ridging set to dominate
conditions next weekend. A cooler overall profile in the wake of
this system with the likelihood for an easterly component to low
level flow means temperatures near average, with dry conditions
favored throughout the weekend.

MARINE...

West to northwest flow in the wake of a cold front will continue to
produce gusts to gales across the northern-third of Lake Huron
through the morning hours. Wind gusts to gales will then diminish
quickly through the late morning and afternoon hours once high
pressure moves in and settles over the Great Lakes. Lighter winds
will carry on through the midweek period given the continued
influence of higher pressure, which will maintain a weak pressure
gradient. The next active weather system will move in Friday, which
will bring the next chance for active weather and some elevated wind
gusts.

&&

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

$$

AVIATION.....TF
DISCUSSION...MR
MARINE.......HI


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