240
FXUS63 KDTX 080958
AFDDTX

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
558 AM EDT Mon Jun 8 2026

.KEY MESSAGES...

- Mostly dry conditions and warmer temperatures today.

- Showers and thunderstorms tonight and tomorrow will pose a locally
  heavy rainfall threat.

- Wednesday and Thursday will see hot and humid conditions along with
  additional thunderstorm chances.

&&

.AVIATION...

Lingering influence of high pressure, now over Quebec, ensures
another day of light southeast winds and dry weather. A pattern
shift emerges late tonight into Tuesday with the development of low
pressure that tracks from southern Iowa into Wisconsin. Rapid
moisture transport early Tuesday morning will draw the first band of
showers, possibly a few decaying thunderstorms, into the airspace
after ~06z. This will also cause ceilings to lower to low VFR/MVFR
by daybreak. Weak instability in the morning limits confidence in
thunder, so opted for broad shower coverage with this TAF issuance.
Thunder potential then increases early Tuesday afternoon with the
arrival of the surface warm front and subsequent destabilization.

D21/DTW Convection...There is a low chance for thunderstorms late
tonight-early Tuesday morning as a moisture-rich airmass rotates
into the region. Lead wave of possible convection reaches DTW around
05z-09z, although with decaying intensity and an uncertain amount of
instability to work with. Low thunder chances persist through
roughly 16z, then increasing into the afternoon as instability
improves.

.DTW THRESHOLD PROBABILITIES...

* Low for cigs aob 5000 feet this evening becoming high by Tuesday
  morning.


* Low for thunderstorms 05z through 16z Tuesday. Medium after 16z
  Tuesday.

&&

.PREV DISCUSSION...
Issued at 400 AM EDT Mon Jun 8 2026

DISCUSSION...

Surface high pressure slides through the eastern Great Lakes today
with the high amplitude ridge to follow. Dry conditions are expected
to hold throughout the bulk of the daylight hours while still under
the influence of the high pressure. An increase in mean thickness
today will lead to a bump in afternoon high temperatures this
afternoon into the mid and upper 80s for most of the area.

A lower amplitude wave will be lifting into the Midwest being drawn
northward by the larger trough over the Canadian Rockies. The
increasing low level jet flow with this approaching wave will lead
to moisture transport of rich moisture environment with ties to the
Gulf into Michigan tonight and tomorrow. Initial sign of this
moisture will be with increasing cloud cover and POPs creeping into
southwest portions of the CWA late this afternoon. Greater POPs look
to hold off until after 8 pm this evening as scattered activity
arrives with the lead ascent. Likely showers and scattered
thunderstorms expected during the day Tuesday supported by larger
scale ascent with the wave moving overhead and increasing diurnal
instability. PWATs are expected to climb to around 2.00 inches,
which will be well above climatological norms and ranking around the
99th percentile, while surface dewpoints climb to the mid/upper 60s
to low 70s. Forecast soundings continue to indicate tall skinny CAPE
profiles, weak cloud layer winds, and warm cloud depth. The result
will be convection that will pose a locally heavy rainfall threat
given the impressive moisture that will available along with the
slower storm motion. The overall severe threat will remain low given
the weak shear profiles, but isolated strong winds will remain
possible given the potential for water loaded downbursts.

Return flow becomes established Wednesday east of troughing
extending across the northern plains into the upper Midwest. This
will lead to strong low level warm advection that will send 850 mb
temperatures to around 20C. Forecast will continue to highlight the
mid to late week heat and humidity. NBM continues to be on the
higher side of guidance, but airmass will be supportive of
temperatures well into the 80s and possibly low 90s as surface
dewpoints hold in the 60s to low 70s. This would put heat indices
that will approach 100 degrees if the higher temperatures look to
verify. The higher temperature outcome will be dependent on the
convective potential and associated cloud cover both Wednesday and
Thursday. Stronger southwest flow with increasing bulk shear and
moderately strong instability elevates the severe weather potential
both Wednesday and Thursday/Thursday night.

MARINE...

High pressure will center over New England this morning which will
back wind direction from east to southeast. Winds will remain light
with dry weather expected for most of the day. A weak low pressure
system will arrive late tonight into tomorrow which will bring
scattered to numerous showers and a chance for some embedded
thunderstorms. There will be some additional chances for rain
showers and thunderstorms Wednesday into Thursday. The overall
pressure gradient will stay weak, holding wind gusts aob 20 knots
through the middle of the week, with some localized stronger gusts
possible with any thunderstorms.

HYDROLOGY...

A moisture rich environment will pose a locally heavy rainfall
threat late tonight through Tuesday. Majority of ensemble members
put QPF amounts within 0.25" to 0.75", but the environment will be
supportive of pockets of 1.00" to 2.00" rainfall amounts or greater.
Thus, highly variable amounts are expected across southeast
Michigan. Convective rainfall rates will have potential to reach
1.00" or greater at times, especially during the day Tuesday. Low
confidence exists at this time as to where these heavier pockets of
rainfall would fall, but the environment will certainly support
isolated flash flooding potential especially if it occurs over any
urban areas or flood prone areas.

&&

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

$$

AVIATION.....MV
DISCUSSION...AA
MARINE.......AM
HYDROLOGY....AA


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