241
FXUS63 KDTX 060929
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
529 AM EDT Mon May 6 2024

.KEY MESSAGES...

- Dry weather with some high clouds today.

- There is a risk for isolated strong to severe storms Tuesday
evening southwest of a FLint to Detroit line.

- There is another chance for showers on Thursday.

&&

.AVIATION...

High pressure over the northern Great Lakes today will lead to east-
northeast winds today (around 10 knots), which will dry out the low
levels. Thus, any lingering patches of low clouds (2-5 kft) around
at the start of the taf period should dissipate. There will be high
clouds around through the day however, as an upper level wave tracks
through the Ohio Valley. Surface ridge holds Monday evening, leading
to very light winds and mainly clear skies in the low levels once
again. However, increasing southeast winds just above the surface
overnight will lead to an increasing moisture/chance of low cloud
development over the southern TAFs late tonight.

For DTW/D21 Convection...No thunderstorms expected through 18z
Tuesday.

DTW THRESHOLD PROBABILITIES...

* Medium in cigs aob 5000 feet Tuesday morning, high Tuesday
  afternoon.

&&

.PREV DISCUSSION...
Issued at 307 AM EDT Mon May 6 2024

DISCUSSION...

Surface high pressure will become centered over Lake Huron today,
tucked under a mid level ridge axis over Lower Mi. Easterly flow
circulating around this anticyclone will sustain ample dry air in
the low to mid levels today. A short wave impulse over the Mid
Mississippi Valley early this morning is however driving an
abundance of high level clouds across southern Michigan. Model RH
probs indicate these high clouds will remain in place through the
afternoon as this short wave feature tracks across the Ohio Valley.
These clouds and the easterly sfc winds associated with the high
will keep afternoon highs in the 60s, with cooler readings along
Lake Huron. The high clouds are expected to exit to the east late
this afternoon and evening as the short wave feature weakens as it
heads toward the Mid Atlantic. Clearing skies with an expected
weakening of the sfc gradient as the high expands across the eastern
lakes will support ideal radiational cooling conditions tonight
given the dry boundary layer. Nighttime mins will drop into the 40s
accordingly.

An deep upper low will evolve from a highly amplified long wave
trough over western NOAM and is forecast to become centered over the
northern high plains by Tuesday. The associated occluded sfc low
will have a warm front extending eastward all the way to the Ohio
Valley. An intense mid/upper level jet lifting out of the southern
plains will take aim on Lower Mi Tuesday afternoon/evening. A ribbon
of enhanced isentropic ascent along the nose of the mid level jet is
forecast to traverse Se Mi roughly in the 21Z to 00Z time frame late
Tuesday. Latest hi res guidance indicates the axis of forcing
narrowing as it lifts across southeast Michigan, which may only
support a band of scattered to broken showers. Some degree of
instability is then forecast to advect into Se Mi during the evening
along the sfc warm front. Given the late day timing, sfc based
instability may struggle to make inroads too far into the forecast
area. Ample elevated instability amidst steepening mid level lapse
rates will still support a chance of thunderstorms area wide, with
hail being a concern, Given 0-6km bulk shear values of 60-70 knots, a
marginal risk for severe storms is in the current day 2 soutwest of
a Flint ot Detroit line, which has the better potential to see some
late day surface based instability.

Mid level dry air will expand across Se Mi by Wednesday. Model
soundings indicate respectable mixing depths by afternoon, which
will warrant warm afternoon highs from the mid 70s to near 80.
Ensemble spread increases markedly with respect to timing/amplitude
of short wave energy forecast to lift out of the central high plains
and across the Ohio Valley/southern lakes region Wednesday
night/Thursday. The latest 00Z model suite is at least supportive of
a chance of rain and continue to hold the better instability south
of the state.

MARINE...

High pressure built over the region overnight and will hold into
Tuesday. During this time, variable winds under the high will
generally hold under 15 knots with low wave heights. Next chance of
showers and thunderstorms comes Tuesday afternoon through Tuesday
night as a warm front gets pulled up through the Great Lakes. Winds
will become easterly Tuesday with gusts 15 to 20 knots. After a
possible lull in precipitation on Wednesday, a low pressure system
will then target the area on Thursday bringing another chance for
showers and thunderstorms. At this time winds and waves are likely
to remain below marine headline criteria through the forecast.

&&

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

$$

AVIATION.....SF
DISCUSSION...SC
MARINE.......DRK


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at www.weather.gov/detroit.