760
FXUS63 KDTX 290747
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
347 AM EDT Wed May 29 2024

.KEY MESSAGES...

- Light showers will carry through the morning near the Ohio border
as a low pressure system passes to the south. Additional scattered
showers and isolated thunderstorms will develop early this afternoon
mainly south of I94.

- Dry weather builds in later today which continues through late
week.

- Temperatures drop below average throughout the mid week period
before warming up again into the weekend.

&&

.DISCUSSION...

The broad trough over the Great Lakes will offer one more chance at
showers and isolated thunderstorms today as a mid level short wave,
surface low, and sinking cold front all work together in a way to
use the last of the moisture before it`s shunted to the south. Main
focus for early day showers will be the ongoing band stretching from
southern Lake MI to Cleveland on the deformation/moisture axis of a
surface low that will track along that same line. The compact mid
level wave and surface reflection will reach south of CLE by 12Z
this morning with the band of showers pivoting up into SE MI. These
showers will mostly affect locations south of I94 but there are some
isolated showers already developing up toward M59 as well. A cold
front will then push southward through the early afternoon which the
CAMs are mostly showing sparks up another round of showers and
possible some isolated thunderstorms. The residual moisture pool
with PWATs up near 1.0 inch and cooler air in the mid levels briefly
enhance the lapse rates and produce up to 500 J/kg of MUCAPE. This
is all while dry air advection is underway so expectation is for a
burst of diurnally driven cu that may develop into scattered showers
with an isolated thunderstorm that will fade quickly in the late
afternoon due to lack of greater forcing and moisture. Again this
will largely be south of I94 so most locations north of M59 should
stay dry through the day.

Expansive surface ridge will then begin to build into the area late
in the day and overnight. The high will be centered off to the west
keeping northerly flow persisting over SE MI overnight. Dry air with
dewpoints falling into the 30s with clear skies and decreasing winds
will offer fairly good radiational cooling conditions. Low
temperatures are forecast down to around 40 but would not be
surprised to see a few cooler spots come in with an upper 30. The
short nights this time of year along with any lingering moisture
being pushed out will both help minimize the extent of those sub 40
values.

Thursday and Friday will be dry with a gradual warming trend back
into the 70s as the surface low becomes centered over the Great
Lakes and amplified upper level ridge reaches the region. The ridge
axis passes east Friday evening opening the door for warmer
southwest flow into the region boosting temps further pushing 80 on
Saturday and into the 80s on Sunday. The next trough is already
pushing across central Canada at this time with an extension
southward through the Plains which will accompany the lead edge of
the warm advection push early Saturday. The pattern flattens out and
becomes progressive again which keeps us on the warmer side of the
jet into next week but also presents periodic opportunities for
precipitation next week.

&&

.MARINE...

Surface trough departs this morning in favor of high pressure moving
in from Canada this afternoon. Transition between these pressure
patterns results in a period of enhanced northerly flow through this
evening, with a combination of gusts to 25 knots and waves of 3 to 5
feet prompting additional Small Craft Advisories for today and
tonight. Drier conditions prevail to end the work week with winds
organizing out of the southwest by this weekend.

&&

.PREV DISCUSSION...
Issued at 1055 PM EDT Tue May 28 2024

AVIATION...

Lingering high based showers diminish through the early morning
hours. Otherwise, extensive cloud generally between 6 and 10k ft
will mark the overnight period. Despite the recent rainfall,
sufficient gradient flow from the northwest limits fog potential for
the early morning period. A general increase in diurnal cu on
Wednesday as moisture associated with a low pressure system to south
slowly vacates the region. This may trigger a low coverage of
showers/t-storms of limited duration across mainly the Detroit
corridor Wednesday afternoon. Winds prevailing from the north
Wednesday, with some intermittent gusts to 20 knots possible.

For DTW/D21 Convection...A brief window for isolated thunderstorm
development will exist Wednesday afternoon.

DTW THRESHOLD PROBABILITIES...

* Low in ceilings aob 5000 feet through through Wednesday.

* Low for thunderstorms Wednesday afternoon.


&&

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

     Small Craft Advisory from 10 AM this morning to 10 PM EDT this
     evening for LHZ442-443.

Lake St Clair...None.
Michigan waters of Lake Erie...None.
&&

$$

DISCUSSION...DRK
MARINE.......MV
AVIATION.....MR


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