textproduct: Detroit/Pontiac

KEY MESSAGES

- Heavy rain showers moving through the Detroit Metro Area end by early evening.

- Low clouds and fog are expected tonight, with potential areas of dense fog significantly reducing visibility.

- Milder temperatures move into the area Friday-Saturday with daytime highs in the 60s to near 70 degrees on Saturday.

- A chance for strong to marginally severe thunderstorms late Friday night through Saturday afternoon. Damaging winds and hail are the primary concerns.

- Even without storms, it will become windy Saturday afternoon. Southwest winds are expected to gust between 40-45 mph.

- After a brief cool-down, well-above-normal temperatures in the 60s are expected to return early next week.

DISCUSSION

Low pressure is tracking through northern Ohio this afternoon, passing east of the Eastern Great Lakes this evening. Heavy rain showers with compact upper level wave/deformation will come to an end before 00z with mid-level drying and upper-level ridging building over the Central Great Lakes tonight. However, a lack of low level cold advection/drying and weak flow near the surface in the wake of the low will likely produce low clouds and fog, as surface dew pts remain elevated (above 32 degrees) over the frozen ground. A dense fog advisory may be needed tonight for parts of the CWA, as a light southeast component off Lake Erie/Lake ST. Clair/southern Lake Huron helps the cause. However, low clouds depths may be sufficient to produce even some drizzle, so not sure fog will end up being widespread 1/4sm or less, as winds attempt to increase slowly around sunrise.

A highly amplified upper level pattern continues, with summer-like upper level ridge off the East and an upper level trough extending along and west of the Rockies. A strong upper level wave will eject out of the Four Corners region on Friday. An extreme low level jet traversing through Lower Michigan Friday night - Saturday as an aggressive height fall center and associated surface low tracks through Eastern Lake Superior or close to the Straights. 12z NAM suggests surface dew pts rising to 60 degrees, supportive of 1000- 850 MB capes in the 500-1000 J/kg range. Favorable late afternoon timing of the cold front draws concerns for damaging winds with any stronger convection, due to the strong left over jet- at least 50 knots at 850 MB. Mid-level lapses rates are decent, and with favorable wet bulb zero heights around 10000 feet, hail is also possible. No issues with the marginal risk issued by SPC for day 3. Even without any thunderstorm development, gradient winds/boundary layer mixing will likely approach wind advisory criteria/40-45 mph per local probabilistic guidance, as there looks to be 45+ knot of flow at 925 MB level. 925 MB temps at or slightly above 14 C supports highs around 70 degrees, but will be dependent on the coverage and duration of the showers.

Short lived cold shot shot (850 MB temps slightly negative) Saturday night with rebounding heights and warming to finish the weekend into early next week. Temperatures once again well into the 60s for Monday and Tuesday, with even 70 degrees possible on Tuesday (per about half euro ensemble members). This is dependent on elevated warm front lifting through, which could lead to showers and cooler temps.

MARINE

Weak area of low pressure continues to slide along the length of Lake Erie this evening bringing showers to the southern half of the region. Departure of the low overnight brings a period of drier weather as well as lighter winds shifting to the southeast. A stronger low then lifts out of the Plains and into the northern Great Lakes Saturday. In advance, the attendant warm front lifts through the central Great Lakes late Friday supporting another round of showers and a shot at a few thunderstorms with southwesterly winds developing post-front Friday night. While strengthening warm advection results in 50-55kt flow only a couple thousand feet off the surface, magnitude of the airmass maintains strong thermal stability over the lakes keeping winds at or below 30kts. System's cold front crosses the region second half of the day Saturday generating wider spread showers and scattered thunderstorms, particularly towards the southern Great Lakes. An isolated strong to severe storm is possible over these southern waters. There remains a couple hour window along/immediately following the front where west/west-northwest gusts could near entry-level gales. That said, while the gradient is supportive of stronger gusts, trailing airmass is not particularly cold relative to the current lake temps resulting in only slightly unstable to neutral thermal profiles acting as an inhibiting factor in peak wind speed potential. Confidence at this time is not high enough to warrant a Gale Watch.

PREV DISCUSSION

Issued at 1228 PM EST Thu Mar 5 2026

AVIATION...

A range of flight conditions cover southern Lower Mi this afternoon driven by proximity to the front stalled across IN/OH. LIFR/IFR in fog and stratus is widespread up to PTK transitioning to borderline IFR/MVFR farther north from FNT to MBS. This general setup holds this afternoon as rain showers spread across the area, especially south of FNT, as a ripple of low pressure runs along the frontal zone. That system exits eastward this evening, however the IN/OH front remains stalled there through tonight in a favorable position to maintain or redevelop IFR/LIFR across the region. Cool easterly wind off the eastern Great Lakes into Lower Mi helps maintain saturated boundary layer conditions already supported by the stalled frontal zone, also enhanced by gradual nocturnal cooling into Friday morning. The next low pressure system draws the front northward into Lower Mi while maintaining LIFR in typical warm frontal fashion through Friday morning.

For DTW... LIFR/IFR conditions persist this afternoon in a mix of fog and stratus, enhanced by cool easterly wind and rain showers increasing across the region. The rain exits eastward this evening while LIFR/IFR ceiling and fog continue tonight through sunrise Friday.

DTW THRESHOLD PROBABILITIES...

* High for ceiling at or below 5000 ft this afternoon through Friday morning.

* Moderate for ceiling and visibility below 200 ft and/or 1/2SM tonight into Friday morning.

DTX WATCHES/WARNINGS/ADVISORIES

MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None.