129
FXUS63 KDTX 110723
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
323 AM EDT Sun Aug 11 2024

.KEY MESSAGES...

- Conditions today again marked by below normal temperatures and
breezy westerly winds.

- Dry or mainly dry weather, with just a slight/low chance of brief
showers today, and sporadic brief times next week.

- Near normal temps expected next week.

&&

.DISCUSSION...

Higher amplitude mid level troughing entrenched locally early this
morning, as meaningful height falls emanate from a closed mid level
circulation over eastern Ontario/western Quebec. Plume of higher mid
level moisture evident on satellite pivoting through a perturbed
cyclonic flow contributing to some widely scattered light showers,
despite a general lack of greater moisture quality or depth. This
underlying profile to receive an additional boost to the upward
vertical motion field with time via a combination of a mid level
trough passage and improving diurnal lapse rates environment beneath
the inherent cold pool. This lends to a persistent lower end chance
for light shower production today, with greater prospects edged
higher with northward extent. The cooler resident thermal profile
again translates into highs in the 70s.

Confluent mid level northwest flow suggests a higher degree of
underlying stability for Monday. Weak signal remains for a very
minor potential /less than 20 percent/ for shower development at
peak heating as lapse rates attempt to steepen sufficiently.
Sufficient recovery within the mean thickness field to bring
temperatures back closer to average to begin the work week. Similar
overall conditions into Tuesday, with no evidence of meaningful
thermal advection to shift toward a more noteworthy warming trend
yet. There remains some potential for a still ill-defined shortwave
to transit the region during the daylight hours. An infusion of dcva
to capitalize on steeper lapse rates could prove sufficient toward
generating a low end coverage of convective showers sometime within
the late Tuesday/early Tue night window. Blended model guidance
holding firm with a dry forecast, but enough evidence in the
individual solution space to provide a limited mention attm.

Seasonable and generally benign conditions in store for the Wed-Thu
timeframe. Ridge of high pressure anchored just to the east
maintains influence under a building upper height field. Retention
of a low level southeasterly gradient mutes the overall potential
for a more meaningful warming trend. Highs projected to arrive in
the lower 80s. Transition toward a potentially more active pattern
to finish the work week, with conditions governed by behavior of
stronger height falls ejecting out of the plains and corresponding
convective evolution both upstream and locally. Low predictability
setup at this stage and NBM agrees in offering a modest precip
chance mention.

&&

.MARINE...

Broad upper low still spins just off to the northeast of the Lake
Huron with another trough rotating around it this morning. With
overall pressure gradient weakening with the northward advancement
of high pressure into the southern Great Lakes, weaker winds aloft
to mix down, and lower mixing height, will keep winds under 25 knots
in the nearshore zones although a brief gust or two may reach 25
knots. This is especially the case around the tip of the Thumb
closer to the stronger gradient over the open waters and closer to
the low where winds are still expected to peak around 30 knots
today. There is also a chance for waterspouts over the waters today
with any showers that develop. The high will continue northward,
eventually encompassing the entire region tonight. The high will then
persist through the first half of the week keeping the waters quiet.

&&

.PREV DISCUSSION...
Issued at 1042 PM EDT Sat Aug 10 2024

AVIATION...

Unsettled pattern within cyclonic west/northwest flow will maintain
periods of lower VFR cigs into tonight, but with some scattering out
possible in time. A few showers may also encroach on KMBS/KFNT/KPTK.
An additional diurnal component should then lead to a period of BKN
cigs again Sunday. Westerly flow will of 10 knots or less overnight
with gusts to 20 or more knots by midday Sunday with better mixing.

For DTW/D21 Convection... No thunderstorms are expected.

DTW THRESHOLD PROBABILITIES...

* Low for cigs at or below 5000 ft Sunday afternoon.


&&

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

$$

DISCUSSION...MR
MARINE.......MR
AVIATION.....DG

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