Sunrise 6:06 AM   Sunset 8:50 PM Moonrise 2:07 PM   Moonset 2:32 AM

  Print   HELP   Reset   Save   Recall  New

LCZ422 /o.can.kdtx.ma.w.0007.000000t0000z-240508t0215z/ 1005 Pm Edt Tue May 7 2024
.the special marine warning is cancelled - .
the affected areas were - . St. Clair river - .
the Thunderstorm has moved out of the area and no longer poses a significant threat to boaters.
&&
lat - .lon 4267 8251 4262 8251 4255 8258 4255 8261 4265 8259 4270 8262 4270 8261 4266 8259 4264 8256 4265 8255 4276 8251 4282 8251 4282 8248 4276 8247 time - .mot - .loc 0201z 248deg 49kt 4275 8219

LCZ400
No data

FXUS63 KDTX 170339 AFDDTX

Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1139 PM EDT Thu May 16 2024

KEY MESSAGES

- Numerous showers late tonight and into early Friday morning.

- Chance of thunderstorms Friday afternoon.

- Very warm this weekend through early next week. Increased chances for thunderstorms Monday night into Wednesday morning next week.

AVIATION

Increasing lower VFR cigs in the 5-10kft range will occur into the overnight with eventual scattered showers (and possibly an isolated thunderstorm or two) late tonight into early Friday morning. By Friday morning, MVFR cigs will be more likely even as showers move east of the region. Additional showers/isolated thunderstorms will be possible late in the day as well (20z-02z). Light southeast to south flow will veer to southwest Friday and then become light and variable Friday night.

For DTW/D21 Convection... An isolated thunderstorm is possible within a broader area of showers late tonight. The storms will be elevated and weak but capable of a brief lower visibility downpour through Friday morning. A second window for a thunderstorm or two will occur 21z-01z Friday afternoon/evening. Again, locally heavy downpours will be the main concern (and the exception).

DTW THRESHOLD PROBABILITIES...

* Moderate for ceiling 5000 ft or less late tonight and Friday morning.

* Low for thunderstorms late tonight into early Friday morning and then again by late Friday afternoon/early evening.

PREV DISCUSSION
Issued at 301 PM EDT Thu May 16 2024

DISCUSSION...

Weak afternoon destabilization and inbound height falls across Western Lower Mi is forecast to initiate scattered convection across SW Lower Mi late this afternoon/evening. Remnants of this convection may advance into Se Mi this evening before surface based instability wanes with the loss in daytime heating. Mid level troughing now advancing into the northern and western Great lakes will track across Lower Mi late tonight through Friday morning. Overall, system relative isentropic ascent is forecast to be stronger from the thumb region and points north toward daybreak Friday, and much weaker across the rest of the forecast area. A plume of deep layer moisture (precipitable water values just over an inch) preceding the mid level trough axis and steepening mid level lapse rates (weak elevated instability) will still support scattered to numerous coverage of showers and isolated thunderstorms late tonight/early Fri morning. The increasing cloud coverage and low level moisture advection (sfc dewpoints rising into the 50s) will suppress nocturnal cooling, leading to min temps in the 50s.

Lingering early morning convection will give way to decreasing cloud cover in the wake of the surface trough axis late Fri morning into the afternoon. Recent 12Z model guidance suggests the strongest push of mid level subsidence and subsequent capping will hold off until Fri aftn/evng as mid level negative vorticity advection arrives from the northwest. Lingering sfc troughing over Se Mi combined with sfc dewpoints near 60F and daytime temps well into the 70s will support increasing daytime instability, suggesting some scattered convective development perior to the mid levels becoming capped. Model soundings suggest 0-1KM ML Cape of 800 to 1500 J/kg, focused along the sfc trough axis over the eastern half of the forecast area. Bulk shear parameters of only 20-25 knots will limit the risk for strong to severe convection. There does however appear to be a narrow window of opportunity Fri aftn prior to the strengthening of the mid level cap when convective downdraft potential may be supportive of isolated strong/severe thunderstorms.

Mid level ridging will dominate Lower Michigan through the weekend.
Despite rising mid level geopotential heights on Saturday, an easterly component to the sfc winds off the lakes and the strength of the mid level subsidence will limited mixing potential to a degree, suggesting afternoon highs from the upper 70s to around 80 (with cooler readings near Lake Huron). Further building of the mid level ridge toward the end of the weekend and a shift to a more southerly wind trajectory will push afternoon highs into the lower to mid 80s across most of the forecast area on Sunday.

Persistent low level SSW flow will ensure well above normal temperatures into early next work week, with high probabilities for highs both Monday and Tuesday into the 80s. The 12Z deterministic solutions indicate a short wave trough ejecting out of the southwest across the Great Lakes Mon night, supporting a chance for convection. A more amplified wave is then forecast to eject out of the longer wavelength western US trough across the Great Lakes in the late Tues to early Wed time frame. This will be a more dynamic system, thus supporting greater shower/thunderstorm chances. There is certainly a severe weather potential, predicated to a degree on whether the dynamics can line up with peak instability.

MARINE...

A weak low pressure system lifts across Lake Superior tonight, sending a dissipating front across the central Great Lakes overnight into early Friday. Despite the overall weak system, a disturbance aloft will help provide enough forcing for scattered to numerous showers with isolated non-severe storms to develop after midnight and into early Friday. A weak ridge then fills into the area Saturday into Sunday, promoting continued light winds and mainly dry conditions. The next disturbance moves into the area Monday night into Tuesday with slightly stronger southerly winds along with scattered showers and thunderstorms.

DTX WATCHES/WARNINGS/ADVISORIES
MI...None.
Lake Huron...None.
Lake St Clair...None.
Michigan waters of Lake Erie...None.

toggle option: (graph/table)

Full Color Weather Map

Link to Loop


Other links: GEOS-West     Contential US     Full GOES-East

Detroit, MI,