273
FXUS63 KDTX 142308
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
708 PM EDT Tue May 14 2024

.KEY MESSAGES...

- High pressure brings mainly dry weather and near normal
temperatures for Wednesday.

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

- Warming temperatures to close out the work week and carry through
the weekend, when highs likely reach into the lower 80s on Sunday.

&&

.AVIATION...

Mid/upper clouds will persist across the area around low pressure
circulation to the south and southwest. A portion of this low will
pivot closer to the region tonight with cigs aob 4-6kft thickening
KPTK south. There is some chance of MVFR cigs, especially into the I-
94 corridor. Lower VFR cigs will be slow to erode/pivot away from
area on Wednesday, but expect a gradual clearing trend from north to
south into the end of the forecast period. Northeast winds will
prevail throughout the forecast.

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

DTW THRESHOLD PROBABILITIES...

* Low confidence in cigs aob 5000 feet late tonight into Wednesday
  morning.

&&

.PREV DISCUSSION...
Issued at 324 PM EDT Tue May 14 2024

DISCUSSION...

700 MB moisture axis (5.5 g/kg of specific humidity)/right entrance
upper level jet forcing triggering showers around M-46 to Saginaw
Bay finally waning as low level northeast dry air also continues to
undercut.

Upper level low over the western Ohio Valley with associated low
along the Ohio River, sliding east through tomorrow, with 500 MB
ridge axis (568-570 DAM) building over the Central Great Lakes by
Wednesday evening. Higher low level moisture content and still
backed low level southeast flow this evening near the southern
Michigan border will support a chance of light showers up to the I-
94 corridor, with a slight chance of weak thunderstorm right near
the border. But otherwise, the low level dry air will continue to
make further inroads tonight as low level northeast winds increase
further. Still just enough residual moisture and modest cold
advection around tomorrow to support decent amount of clouds, but
highs still likely making a run aoa 70 degrees south of I-69, farther
removed from the cool flow off Lake Huron.

Upper level energy over the northern Rockies to get booted off to
the east-northeast as 140 knot upper level jet tracks through
southern British Columbia. Lead height fall center to track through
Minnesota Wednesday night-Thursday, but additional weaker height
falls/weak surface reflection to track through Central Great Lakes
on Friday, supportive of unsettled/chance of rain showers to end the
work week with the isentropic ascent/moisture advection. Marginal
instability and modest instability will promote a slight chance of
non-severe thundestorms as well.

Large upper level ridge off the Pacific Northwest coast will sink
south and become more west-east elongated, with some of the warm air
over the Central Rockies breaking off and arriving over the Weekend,
as 850 MB temps progged to exceed 15 C by Sunday, supportive of
lower 80s for highs with favorable southwest winds.

MARINE...

Shower chances will remain possible into the early evening as high
pressure continues to build in over the northern Great Lakes and
pushes the frontal boundary south. There will continue to be a
chance for rain and thunder overnight into Wednesday, mainly over
Lake Erie, as low pressure moves eastward across the Ohio Valley.
This low pressure system will reinforce northeast flow across all of
the Great Lakes, building wave heights into Saginaw Bay and across
the Lake Huron shoreline on Wednesday. Small Craft Advisories may be
needed across Saginaw Bay and portions of the Lake Huron shorelines
given wave heights building slightly above four feet. High pressure
will continue to settle in over the Great Lakes on Thursday,
relaxing wind speeds and subsequently wave heights.

&&

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

$$

AVIATION.....DG
DISCUSSION...SF
MARINE.......SS


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at www.weather.gov/detroit.