171
FXUS63 KDTX 160357
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
1157 PM EDT Sun Sep 15 2024

.KEY MESSAGES...

- Seasonably warm and dry conditions prevail through mid-week with
patchy morning fog Sunday through Tuesday.

- Spotty light rain becomes possible Wednesday.

&&

.AVIATION...

Expansive area of high pressure maintains influence this period.
This ensures dry and stable conditions, precluding lower cloud
development. Shallow ground fog will again be possible at daybreak
Monday due to favorable radiative cooling conditions. Light winds
generally from the southeast persist.

For DTW/D21 Convection... Thunderstorms are not in the forecast for
the foreseeable future.

 DTW THRESHOLD PROBABILITIES...

* None.

&&

.PREV DISCUSSION...
Issued at 349 PM EDT Sun Sep 15 2024

DISCUSSION...

A longwave blocking ridge over much of eastern North America will
continue to dominate the weather through the midweek period at
minimum. A strong anticyclonic vorticity advection signal is progged
on Monday as a remnant dipole high maximum aloft retrogrades back
into the area from the east. Ridge reinforcement is then advertised
for Tuesday and Wednesday as right exit region dynamics from the
center of the country spread northeastward with time. Just a
remarkable stretch of persistence weather continuing with daytime
highs in the lower 80s and nighttime lows dropping into the 50s.
Again, the preference has been to side with EC-AIFS for temperatures
since blended gridded guidance continues to run high. Patchy morning
ground fog each of the days will give way to clear skies.

The blocking ridge will slowly evolve into a pseudo rex feature this
week with heights lowering and a coalescing of deeper moisture
content over the Southeast United States. Models differ on the
details and timing of the moisture advection to the northwest with
time. Latest thoughts are a lobe of absolute vorticity will push
into the area increasing high cloud Tuesday with 850-600mb thetae
then arriving over the far southeastern CWA sometime Wednesday.
Forecast soundings show moist adiabatic lapse rates at moist
adiabatic above 10.0 kft but a fair amount of high static stability
lingering between 2.5 and 7.5 kft agl. Slight chance PoPs at 20% or
less are sufficient for now. A strong ridging max of the rex block
is then expected to be in close proximity of the area and will
likely perpetuate quiet weather into next weekend.

MARINE...

High pressure continues to dominate conditions across the central
Great Lakes through the first half of the week. Light (aob 15kts)
southerly flow holds through Monday before turning back to more
easterly midweek.

&&

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

$$

AVIATION.....MR
DISCUSSION...CB
MARINE.......KDK


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