635
FXUS63 KDTX 270737
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
337 AM EDT Thu Jun 27 2024

.KEY MESSAGES...

- Cool airmass around today supporting highs in the 70s, with lows
dipping into the mid 40s to mid 50s tonight.

- Showers and strong thunderstorms expected to return by Saturday.

- Cool and dry weather for the second half of the weekend.

&&

.DISCUSSION...

A cool start to the day over southeast Michigan, but late June
insolation will allow temperatures to climb back into the 70s,
warmer south, farther removed from the northerly flow off Lake
Huron. Area of low clouds moving through southeast early this
morning will dissipate and give way to modest fair weather diurnal
Cu up by afternoon. Tonight`s lows look even cooler compared to this
morning, as afternoon dew pts dip into the mid 40s to lower 50s.
Would expect the good radiators across the Thumb region to follow
suite and dip into the mid/upper 40s with the center of the surface
high holding for a good portion of the night before retreating off
to the east for Friday.

Return flow around the high will ramp up through the day on Friday,
with increasing high clouds. Surface dew pts still likely struggling
to reach 60 degrees by day`s end.

Model trends for Friday night are dramatic, with bulk of the
solutions suggesting a weaker warm front with convection firing up
over the Midwest tending to fizzle out or tracking just southeast of
the area. Unfortunately, still timing uncertainty with the actual
cold front on Saturday and amount of destabilization during the day,
as good 0-6 KM bulk shear arrives by early Saturday evening. Lead
surface moisture axis/trough likely triggers showers and
thunderstorms Saturday morning already, which of course would limit
severe chances. With that said, SPC day 3 indicating a marginal risk
of severe thunderstorms for all of southeast Michigan.

Another healthy shot of cold air to follow for the second half of
the weekend, with 850 MB temps progged to lower to 6-8 C, per 00z
Euro. Airmass looks very dry and stable (showalter index around 10
C), thus not expecting showers despite the embedded upper level wave
in the fairly sharp 500 MB trough axis progged to swing through
Sunday evening.

&&

.MARINE...

High pressure moves over the Great Lakes today and brings clear
skies and gentle winds over Lake Huron. Cold, northerly flow
switches to southerly flow overnight as the high pressure center
passes over Lake Huron. Winds re-strengthen up to 20 knots with
gusts to 25 over Northern Lake Huron. The next low pressure system
is set to track into the Great Lakes on Saturday and bring chances
for showers and storms.

&&

.PREV DISCUSSION...
Issued at 1138 PM EDT Wed Jun 26 2024

AVIATION...

Patch of lower VFR/MVFR stratus over Saginaw Valley and Thumb will
shift south overnight with northerly flow from Lake Huron most
likely allowing for some expansion into early Thursday morning.
Otherwise, expect VFR conditions as any BKN conditions early mix to
FEW-SCT during the day Thursday.

For DTW/D21 Convection...No convection is expected this forecast
period.

DTW THRESHOLD PROBABILITIES...

* Low for ceilings aob 5kft overnight within developing north flow
  in the wake of cold frontal passage.


&&

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

$$

DISCUSSION...SF
MARINE.......BC
AVIATION.....DG


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