757
FXUS63 KDTX 151108
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
708 AM EDT Wed May 15 2024

.KEY MESSAGES...

- Few lingering light showers south of I-94 this morning. Otherwise
dry weather returns as clouds gradually clear north to south today.

- Scattered to numerous showers and possible embedded thunderstorms
return Thursday night and Friday.

- Active pattern holds this weekend into the beginning of next week
with warmer temperatures and shower/storm chances most days.

&&

.AVIATION...

Low pressure exiting the Ohio valley grazes the DTW corridor with
brief MVFR ceiling early this morning. Otherwise, mid and high
clouds gradually diminish from MBS southward throughout the day.
High pressure in northern Ontario supplies a steady NE wind across
the area leading to clear sky this evening. Cloud level wind veering
easterly hints at a resupply of low to mid clouds late tonight
reaching borderline MVFR into Thursday morning.

For DTW/D21 Convection...Thunderstorms are not expected during this
forecast period.

DTW THRESHOLD PROBABILITIES...

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

&&

.PREV DISCUSSION...
Issued at 336 AM EDT Wed May 15 2024

DISCUSSION...

Surface low pressure and parent mid-level trough remain over the
Ohio Valley today before shortwave energy shifts east to reorganize
into a mid-Atlantic coastal low. Locally, the slow departure
supports continued a low chance (~15-25%) for scattered showers over
areas along/south of I-94- greatest potential focused over
Lenawee/Monroe counties. For the rest of the CWA, dry air advection
amidst NE flow lends to a gradual though steady north-to-south
clearing of cloud cover with areas north of I-96/I-696 likely
experiencing mostly sunny-partly cloudy skies by late this afternoon
(sunniest north). Seasonably average day for inland areas today as
high top out in the low to mid 70s. Areas down wind of Lake Huron,
ie Tri-Cities/Thumb, hold cooler in the 60s with areas closest to
the shoreline likely struggling to get out of the 50s.

Mid-level ridging in advance of another mid-upper trough ejecting
out of the Rockies slides across the central Great Lakes Thursday.
Pleasant day as winds shift to the southeast in response allowing
most areas to see temperatures reach the mid 70s even with
increasing clouds through the day. These clouds mark the lead edge
of height falls tied to the aforementioned Rockies trough that will
fully expand over southern lower MI Thursday night and Friday.
Weakening surface low pressure lifting through the upper Midwest
sends a washing out cold front toward the region supporting shower
chances overnight into Friday morning. Thunder chances are low but
non-zero as mid-range solutions advertise a few hundred J/kg of
elevated instability attempting to creep into the state. Mid-level
trough settles over the Great Lakes daytime Friday providing upper
level support for afternoon shower and thunderstorm redevelopment.

Muddled pattern going into this weekend as separate northern and
southern stream waves traverse the central CONUS. Southern stream
wave tracks through the Ohio/Tennessee valleys Saturday maintaining
weak mid-level troughing over the southern Great Lakes. This offers
a shot for diurnal pop-up showers/storms Saturday afternoon with
long range models suggesting a few to several hundred J/kg of MLCAPE
to develop during peak heating. Northern stream wave flattens the
western ridge and largely prevents its significantly warmer airmass
over the Southwest/Plains from reaching into the Great Lakes as the
trough`s associated weak cold front is instead driven through the
Great Lakes Sunday. Weak frontal forcing and lack of upper support
with the parent shortwave/PV residing over the northern Great Lakes
looks to limit precip chances locally with northern areas having the
best shot at seeing rain. Near zonal northern jet is then progged to
set up for the early week period allowing a series of shortwaves to
track into the central Great Lakes maintaining our more active
recent pattern.

MARINE...

Low pressure lingers over the Ohio Valley today supporting continued
shower chances over Lake Erie, at least for the first half of the
day. Modest gradient and sunnier skies in the north promote better
mixing supporting an uptick in northeast flow into the Thumb
nearshore waters this afternoon. This is especially true for the
Saginaw Bay as favorable wind direction funneling down the bay is
expected to support gusts between 25-30kts. Small Craft Advisories
are in effect today for the all the Bay as a result as well as the
Port Sanilac-Port Huron nearshore zone due to higher wave action.
High pressure then briefing slides across the region Thursday
bringing favorable marine conditions. Active pattern with showers
and perhaps a couple thunderstorms return Thursday night into Friday
as weakening low pressure lifts in the upper Midwest.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...

MI...None.

Lake Huron...Small Craft Advisory until 8 PM EDT this evening for LHZ421-422.

     Small Craft Advisory from 4 PM this afternoon to 11 PM EDT this
     evening for LHZ443.

Lake St Clair...None.

Michigan waters of Lake Erie...None.

&&

$$

AVIATION.....BT
DISCUSSION...KDK
MARINE.......KDK


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