167
FXUS63 KDTX 062309
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
709 PM EDT Thu Jun 6 2024

.KEY MESSAGES...

- Still breezy on Friday with high temperatures topping out around
  70 degrees.

- Temperatures running below normal over the Weekend into Monday,
with a good chance of showers Saturday afternoon/evening.

&&

.AVIATION...

Stronger westerly winds this afternoon diminish around sunset, but
still likely hold sustained around 10 knots tonight.

Cooler air and lower clouds tracking into southern Lower Michigan
from the Western Great Lakes. Isolated-scattered showers will hang
around Saginaw Bay, and could  MBS stand the best chance of briefly
impact being impacted. MBS also stands the best chance for cigs to
reach MVFR by sunrise Friday morning, but preference is to wait and
watch trends, as preference is to hold cloud bases in the 3000-4500
foot level. Diurnal heating on Friday will help slowly lift cloud
bases, with westerly winds picking up again with increasing boundary
layer depths. However, overall winds look to be weaker compared to
today, and expecting wind gusts mostly around 25 knots in the afternoon.

For DTW/D21 Convection...Thunderstorms are not expected.

 DTW THRESHOLD PROBABILITIES...

* Moderate for ceiling 5000 ft or less late tonight and Friday
  morning.

&&

.PREV DISCUSSION...
Issued at 337 PM EDT Thu Jun 6 2024

DISCUSSION...

Breezy westerly winds have gusted above 30 mph, as temperatures have
climbed well into the 70s this afternoon.

12z INL raob indicated 500 MB height of 545 DAM, with a 500 MB temp
of -20 C. The cold core/500 MB low center tracking close to the
Straights and into Georgian Bay tomorrow morning. Stream of upper
level PV/Jet energy on the backside of this circulation will track
through Lower Michigan tonight into tomorrow, triggering
isolated/scattered showers as the mid levels (5000-10000 kft)
steepen up with some modest cape generated. Activity should be
mostly over the Thumb region, closest to the departing upper level
low.

Still breezy on Friday, but the overall wind field looks slightly
weaker compared to today, so would expect only up to 30 mph or so.
Looking at high temperature around 70 degrees with the cooler start
and 850 MB temps progged to reside in the 7-8 C range.

Fast flow over the Great Lakes region this weekend with the jet
stream (110-15 knots at 250 MB) overhead.  Jet forcing and cold pool
tracking through Lake Superior expected to elicit a mid level FGEN
response over Lower Michigan with the tight baroclinic zone in place.
Good forcing is progged to reside over the north half of the CWA
Saturday afternoon, before sinking south Saturday afternoon. NBM
pops appear to be slow in increasing pops.

Perhaps some isolated showers to close out the weekend as cool
cyclonic flow/shortwave tracks through the Central Great Lakes.
Otherwise, upper level ridge builds in early next week (by Tuesday)
supporting cool nights (40s) and dry/mild days (70s).

MARINE...

Small Craft Advisories are in effect for all nearshore zones as post-
frontal winds remain strong and bring potential for hazardous waves.
Chances for some light showers through the rest of the evening today
over northern Lake Huron. Upper level low remains in place tomorrow,
maintaining westerly flow and sustaining chances for light wrap-
around showers. Winds once again reach 20 knots gusting to 25 with a
similar setup to today`s winds, which have been overachieving at
times today. As the upper level low continues to bring chances for
light showers to the Great Lakes and moves off to the east this
weekend, it develops an trough to the east, bringing a ridge over
Michigan and an associated high pressure to start next week. Winds
lighten slightly to 10-15 knots over the weekend before the high
pressure center settles overhead and brings winds below 10 knots.
The next low pressure system is expected to arrive mid-week next
week.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...None.
Lake Huron...Small Craft Advisory until 10 PM EDT this evening for LHZ421-422-
     441>443.

Lake St Clair...Small Craft Advisory until 10 PM EDT this evening for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory until 10 PM EDT this evening for LEZ444.

&&

$$

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


You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.