D21 Tracon Decision Support

204 PM EDT Tue May 19 2026
.AVIATION...

Another hot and humid day (by mid-May standards) lends potential for
diurnal convection this afternoon and early evening. To the west of
the terminals, initial updrafts are testing what little remains of
the capping inversion layer, characterized by shallow updrafts and
limited glaciation/lightning. Meanwhile, sufficient daytime
insolation should lead to surface-based instability within the next
couple of hours marking an expansion in convective coverage across
some of the terminals. Confidence is highest from PTK south, but
uncertainty in overall coverage/intensity of thunderstorms remains.
FNT will be right on the edge of the pre-frontal troughing so opted
for a VCTS mention as opposed to a TEMPO for thunder the rest of the
PM hours. Visibilities will drop to IFR in the heaviest downpours.
Non-convective gusts have stayed elevated given the ambient wind
fields, but expect enhancements within water-loaded downdrafts.
Nocturnal stabilization emerges overnight as gusts drop-off, and
gradient winds gradually veer toward the north throughout the
overnight hours. Post-frontal northerly flow draws a plume of low-
level moisture through Southeast Michigan late tonight into
Wednesday morning favoring MVFR ceilings.

D21/DTW Convection...Window for scattered convection is focused
between 20Z and 23Z this afternoon/evening, although initial storms
could drift eastward a bit sooner. Storm motion will be southwest to
northeast around 40 kt while the corridors of storms migrate west to
east. IFR visibility reductions possible in heaviest downpours.

.DTW THRESHOLD PROBABILITIES...

* Medium for thunderstorms 20-23Z today.

* Medium for ceilings at or below 5000 ft through this evening, then
   high early Wednesday.

TAF Dashboard (AWC)

102 FTUS43 KDTX 191735 TAFDTW TAF KDTW 191735Z 1918/2024 21020G30KT P6SM FEW045 FM191900 22021G31KT P6SM BKN040 TEMPO 1920/1923 3SM -TSRA OVC035CB FM200100 25013KT P6SM SCT040 OVC070 FM200400 28011KT P6SM BKN040 BKN250 FM200900 33009KT P6SM OVC025 FM201400 35008KT P6SM BKN035 OVC120 FM201700 02007KT P6SM FEW040 OVC250=

pWind

pWind Direction Change

Ensemble Wind Direction Distribution

Forecast hourly 18 hours - 3 hourly to 36 hours ... Updated Hourly

pGust

Ensemble Wind Gust Distribution

Forecast hourly 18 hours - 3 hourly to 36 hours ... Updated Hourly

DTW Flow Probabilities based on Ensemble Winds

Forecast hour to 18 hours - 3 hourly to 36 hours ... Updated Hourly

DTW Flow Probabilities based on Ensemble Gusts

Forecast hour to 18 hours - 3 hourly to 36 hours ... Updated Hourly

TCF

https://www.aviationweather.gov/tcf

pConvection

WCAA Dashboard

Hourly Snow Rate at DTW	3 Hourly (centered running total) Snow Rate at DTW

Hourly Snow Density at DTW

Hourly Precip Type at DTW

6hr Prob Snow