283
fxus63 kdtx 082216
afddtx
area forecast discussion
national weather service detroit/pontiac mi
616 pm edt sun sep 8 2024
.key messages...
- a light shower or sprinkle cannot be ruled out over the thumb late
tonight and early monday morning.
- breezier midday monday with gusts to around 25 mph.
- mainly dry conditions in-place through the workweek with low
humidity and steadily increasing temperatures.
- thursday will be the warmest day of the week as highs maximize in
the upper 80s to near 90f.
&&
.aviation...
recent uptick in cumulus coverage is quickly mixing out and only
expecting some residual boundary layer based clouds early this
evening. a weak upper-level disturbance upstream of the area will
slide southeast, signaled by the presence of a deck of mid-level
clouds and maybe a light shower - especially across the northern
airspace. meanwhile, winds will continue to relax and back to the
southwest tonight. expecting a rapid re-emergence of somewhat gusty
west/southwest flow monday morning, as a more favorable environment
for mixing works across. as the disturbance exits to the east later
monday, a rather sharp frontal boundary, with assistance from lake
huron, will release south across southeast michigan - starting mid-
afternoon and continuing into the evening. it will take the balance
of the evening to reach the immediate detroit airspace and will lose
much of it`s momentum by then. otherwise, vfr conditions are
expected through the forecast time window - with pockets of ceilings
in the 5-10kft layer.
for dtw/d21 convection...no thunderstorms are forecast through the
taf period.
dtw threshold probabilities...
* low for ceilings at or below 5kft tonight and monday.
&&
.prev discussion...
issued at 239 pm edt sun sep 8 2024
discussion...
a transitional period gets underway this afternoon across southeast
michigan as the pv anomaly that governed conditions throughout the
weekend consolidates over quebec. this adjustment helps clear the
southwestern periphery of the occluded low from the region and
initiates a period of moderating thermodynamics as geopotential
heights begin to rebound ahead of an advancing western conus ridge.
meanwhile, weak cva embedded within a shortwave trough positioned
near the inflection point of the longwave wave pattern descends over
lake superior and lake huron tonight. resulting dynamic ascent
appears rather inconsequential given low specific humidity values
throughout most of the column, but a light shower or sprinkle cannot
be ruled out over the thumb late tonight and early monday morning,
supporting the continuation of entry-level pops (20 percent). clouds
thicken with the passing disturbance causing overnight lows to
rebound into the 50s as more outgoing longwave radiation is
intercepted and re-emitted. additionally, hrrr/rap smoke models
indicate a plume of western wildfire smoke arriving this evening and
overnight, mainly aloft.
surface reflection of the inbound ridge will be quite evident monday
morning as 1024 mb high pressure stretches across the mid
mississippi and ohio valleys by daybreak. flow should theoretically
shift to a more southwesterly trajectory, but the aforementioned
shortwave washes out in the vicinity, forcing a more zonal gradient
wind orientation for the day. still, h8 temps warm to near 12c,
allowing for a shift to climatologically warm readings, in the upper
70s to near 80f via mixing. also increased midday gustiness to
around 25 knots based on enhanced mixed-layer speeds. the synoptic
ridge amplifies into northern canada on tuesday while the axis
drifts eastward. the low-level anticyclone becomes well-established
to the southeast by tuesday afternoon with winds over southern lower
michigan decreasing and trending southwesterly. temperatures warm by
a couple more degrees tuesday, but the core of the thermal ridge
marked by h7 temps of 13c generally remains fixed across the
intermountain west.
the emergence of a secondary upstream ridge axis maintains
seasonably hot and dry conditions wednesday through friday, as daily
highs continue to rise. the hottest day appears to be thursday with
potential for temperatures to approach 90f for the western part of
the cwa. this closed high of 590 dam forms over northern michigan on
thursday while also setting up a rex block once a tropical cyclone
tracks north out of the gulf coast. rain chances will likely hold
off for the area until next weekend once the post-tropical system
breaks down with the assistance of an impending pacific trough. this
allows dewpoints to climb into the 60s for the first time since the
end of august.
marine...
milder air is streaming into the central great lakes this afternoon
with westerly winds topping out at or just above 20 knots. 850 mb
temps progged to rise further, into the lower teens tomorrow
morning, ahead of a cold front dropping south. westerly winds could
briefly approach 25 knots over lake huron, but with the offshore
flow and waves under 4 feet, not planning on a issuing a small craft
advisory. the weak cold front is expected to clear lake huron by
evening, with just light northerly flow following the passage. ridge
of high pressure in place for tuesday will assure light winds, with
just light southerly winds developing during the mid week period as
sprawling high pressures moves to the east coast. with weak pressure
gradient/ridging holding on, light winds look to persist right into
the first half of the weekend.
&&
.dtx watches/warnings/advisories...
mi...none.
lake huron...none.
lake st clair...none.
michigan waters of lake erie...none.
&&
$$
aviation.....mann
discussion...kgk
marine.......sf
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at www.weather.gov/detroit.