550
fxus63 kdtx 310415
afddtx
area forecast discussion
national weather service detroit/pontiac mi
1215 am edt tue mar 31 2026
.key messages...
- periods of showers and thunderstorms will affect the area tonight
through tuesday evening. isolated severe thunderstorms are possible
tonight. scattered severe thunderstorms are possible tuesday with
damaging wind being the primary but also including potential for
large hail and tornadoes.
- a strong cold front fuels storms but also a chance for excessive
rainfall. there is a marginal risk of excessive rainfall mainly
along and south of m-46 tuesday afternoon and evening.
- after the front tuesday night, temperatures drop back to normal or
slightly below normal for wednesday through late week.
- another system will bring rain and a chance of thunderstorms
wednesday night into thursday.
&&
.aviation...
a notable increase in low level moisture under sustained southwest
flow will maintain a weakly unstable environment overnight. this
will sustain a lower probability for some form of convective shower
and thunderstorm activity to develop near a frontal zone draped
across central lower mi and/or through downstream propgation of
ongoing activity over northern illinois. confidence in occurance at
any one location remains low through tuesday morning and precludes a
defined mention outside of mbs early this morning. otherwise, vfr
under intevals of thicker mid-high based cloud into the morning
period. highest likelihood for thunderstorm development will focus
across the tuesday afternoon and evening periods, as a southward
sagging cold front engages increasingly unstable conditions.
outgoing forcast outlines the most likely window, with further
refinement of specific timing expected as confidence improves with
time.
for dtw...very low probability for a shower or thunderstorm late
tonight and tuesday morning. the highest probability exists tuesday
afternoon and evening, with one or more rounds of convection
possible within this window.
dtw threshold probabilities...
* low for cigs aob 5000 ft through tuesday morning, then medium
tuesday afternoon and evening.
* low for thunderstorms tuesday.
&&
.prev discussion...
issued at 306 pm edt mon mar 30 2026
discussion...
afternoon temperatures across se mi have rising into the low 70s
within ongoing low level warm air advection. a surface cold front,
now over the northern great lakes, is forecast to sink south into
the northern saginaw valley/thumb region tonight, forcing the post
frontal lake modified cold air into the far northern sections of the
forecast area. strengthening southwest flow in the low to mid levels
will in turn advect deep layer moisture from the lower-mid ms valley
this afternoon across the southern lakes region tonight. meanwhile,
very steep mid level lapse rates will result in decent elevated
instability overnight (0-3km mu cape possibly over 1500 j/kg). the
initial mid level theta e surge this evening will support a chance
of convection. additional moisture advection overnight within the
time period of steeper lapse will lead to increased convective
chances, especially across the northern half of the forecast area
closer to lower tropospheric frontal forcing. the degree of elevated
instability and strong mid level wind fields will support isolated
strong to severe convection. limited boundary layer stability
suggest strong winds in addition to hail will be the primary severe
weather concerns. ideal hodograph structure along the cold front
across the saginaw valley/thumb raises some concerns for isolated
supercells. this potential looks to be very limited based on weak
surface instability.
there is the potential for a couple of rounds of convection on
tuesday as resident deep layer moisture and an axis of steep mid
level lapse rates reside overhead. low level frontogenetical forcing
will also be present as the aforementioned cold front gradually
sinks south during the day. hi res models present an array of timing
of the convection across the area, much of which will be dependent
upon timing and coverage of nocturnal convection and associated
convective short wave impulses. deep layer shear profiles will
remain supportive of strong to severe convection, predicated upon
the availability of surface based convection. both linear and
supercellular storm structure will be favored based on forecast
hodographs. the passage of the cold front will be marked by a
drastic cool down given the degree of shallow post frontal cold air.
low to mid level anticyclonic flow will envelop the northern great
lakes wednesday, ensuring dry conditions across the northern half of
the forecast area. the cold front is forecast to stall across the
ohio valley, with the elevated portion of the front remaining active
through the day wednesday, warranting chance type pops across the
south. a progressive mid level wave forecast to lift from the
southern high plains wed night into the western great lakes thurs
night will drive the front back north as a warm front wed
night/thursday morning. the thermal profile within the shallow cold
air across the tri cities and northern thumb will support mixed
precip in these locals wed night. recent probabilistic guidance has
reasonably high probabilities for trace to a tenth inch of ice north
of m 46. by thursday most of the forecast area is forecast to be in
the warm sector, suggesting a chance for thunderstorms. medium range
guidance then indicates the surface low and associated cold front
tracking across lower mi thurs night into friday.
marine...
broad southwest flow will veer to the east for most of lake huron by
this evening as the next low pressure system and its warm front gain
influence locally. the shift in flow will also be accompanied by an
expansion of showers and elevated thunderstorms overnight into
tuesday morning, where hail will be the primary threats. the surface
low tracks across northern michigan tuesday afternoon, drawing a
cold front across lower michigan and adjacent marine waters in its
wake. a line of strong to severe thunderstorms will be possible
along the frontal passage tuesday evening, in which localized gusts
in excess of 35 knots will be possible. elevated winds and/or waves
will be driven mainly by thunderstorm activity, as otherwise stable
conditions prevent gusts from mixing to the surface. a cooler post-
frontal airmass then moves in mid-week as flow shifts to the
northwest tuesday night with the fropa. high pressure then drifts
across ontario wednesday, causing winds to veer around the southern
edge of the high before the next system lifts into the area
thursday.
hydrology...
periods of showers and thunderstorms will affect the area tonight
through late tuesday. locally heavy rainfall is likely with the
strongest storms. model ensemble means suggest high probabilities
for 12 to 24 hour total rainfall of 1/2 inch to an inch. there is
however low probabilities for total rainfall of 2 to 4 inches within
regions that see more persistent thunderstorms. localized flooding
is possible, especially in more urbanized areas. a slow moving
frontal boundary will linger across the metro detroit and ann arbor
areas tuesday night into wednesday, supporting additional chances
for light rain. this front is forecast to lift back north wed night,
with a slow moving cold front then forecast to approach thurs into
fri. these systems will produce additional rainfall, with current
projections suggesting additional rainfall remaining an inch or less.
&&
.dtx watches/warnings/advisories...
mi...none.
lake huron...none.
lake st clair...none.
michigan waters of lake erie...none.
&&
$$
aviation.....mr
discussion...sc
marine.......mv
hydrology....sc
you can obtain your latest national weather service forecasts online
at www.weather.gov/detroit.