649
fxus63 kdtx 251748
afddtx
area forecast discussion
national weather service detroit/pontiac mi
1248 pm est sat jan 25 2025
.key messages...
- there is a chance of light snow showers this evening/tonight
producing minor accumulations.
- a modest warming trend for early next week with temperatures
slightly above normal. back below normal during the mid to late
week period.
- monday will be windy with gusts possibly around 40 mph through
most of the day.
- a clipper will pass through the area tuesday night with a cold
front following on wednesday bringing the next chance of light snow.
&&
.aviation...
clear skies prevail for all terminal sites except mbs where
southwest flow is directing pockets of lake enhanced cloud at
issuance. diurnal mixing should generally keep any ceilings above
3.0 kft. narrow band of moisture accompanies a northwest-southeast
cold frontal passage this evening (01z-06z), but bases look to stay
between 4.0-6.0 kft agl. light snow showers/flurries are possible
invof the front, but the forecast has trended much drier in the past
few cycles with little to no accumulation expected. 20-25 knot gusts
accompany the fropa with a shift to nw flow that brings lake
moisture toward the terminals for much of sunday morning. cigs begin
to scatter toward the end of the period.
dtw threshold probabilities...
* low for ceiling at or below 5000 ft today. medium tonight through
sunday morning.
* high in precip type falling as snow.
&&
.prev discussion...
issued at 342 am est sat jan 25 2025
discussion...
today is looking a little quieter than before, not that lot was
expected but snow chances seem lower. models are trending drier in
the boundary layer as southwesterly winds persist through the day.
after the area of stratus pushes east this morning we will have some
mid level clouds streaming in but there may be some breaks in that
cloud deck so some peaks of sun may be possible across the southern
cwa. attention turns toward this evening as a surface low over the
northern plains, embedded in the mid/upper level trough, passes
through northern mi. between 00-06z the cold front will get pulled
through lower mi bringing the next chance of snowfall. setup is not
favorable for a good widespread coating of snow. inversion heights
are low to start, around 5kft, and will drop through the period down
toward 3kft. thermally, we`ll have good low level lapse rates but
the thin saturated layer looks to only touch the -10c layer so won`t
maximize the little moisture with ideal flake growth. best frontal
forcing will be up north of i69 with weaker forcing to the south.
earlier model runs were then showing a god pop of lake effect as
colder air worked in behind the front (850mb temps down toward -
13c), which would light up a period of lake effect off lake mi in
the usual corridor between i69 and m59 between 06-12z. not seeing
that as much the last couple runs with the usual 925mb or 850mb wind
convergence band setting up which will be harder to get across the
state with the potential for sub 3kft inversion heights. so look for
less than an inch of new snow tonight overall.
monday will offer the next feature of note as the next strong mid
level vort max dives down through manitoba and western ontario into
the northern great lakes sending a surface trough across lake
superior. this will usher another arctic airmass toward the region
with 850mb temps down toward -30c nosing into the region. as this
surface trough quickly runs up against high pressure sprawled across
the southern conus, it will compress the gradient leading to a gusty
day. early indications from the nam show an 850mb low level jet
upwards of 60 knots, gfs bufkit soundings show 50 knots down to
900mb, and local probabilities show a high chance of gusts to around
40 knots through the bulk of the day.
a clipper will then dive se through lower mi tuesday night. a
leading isentropic band of snow may track over parts of mid mi
tuesday with the cold front sweeping through wednesday. 850mb temps
drop to -20c behind this front which will drop temps back into the
20s after a few days hovering around freezing earlier in the week.
looks to be a brief period of colder troughing as the ridge already
start building back in friday.
marine...
extended period of troughing resumes today which supports additional
snow showers and an uptick in winds. shallow low-level stability
profiles pair with inbound jet energy driving gusts to near gales at
times tonight, but the west-southwesterly warm advection should keep
peak gusts infrequent enough to preclude any gale headlines. most
likely area for overachievement of gusts lies over the open waters
of northern/central lake huron. a shortwave trough feature rounding
the base of a strengthening 477 dam 500 mb upper low over northern
canada brings higher confidence in strong gradient winds and long-
duration gusts to gales sunday night and monday. a gale watch is in
effect for all of lake huron (us waters) from 10 pm est sunday to 10
pm est monday, and an expansion into lake st. clair and/or western
lake erie is possible in the upcoming forecast cycles. west-
southwesterly gusts to gales of up to 40 knots possible during the
peak of the event.
&&
.dtx watches/warnings/advisories...
mi...none.
lake huron...gale watch from sunday evening through late monday night for
lhz361>363-421-422-441>443-462>464.
lake st clair...none.
michigan waters of lake erie...none.
&&
$$
aviation.....mv
discussion...drk
marine.......kgk
you can obtain your latest national weather service forecasts online
at www.weather.gov/detroit.