Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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207 FXUS63 KDTX 111720 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 120 PM EDT Tue Jun 11 2024 .KEY MESSAGES... - Warming trend through mid-week with high temperatures possibly reaching 90 degrees for Thursday. - The next chance for rain and thunderstorms will be Thursday. Isolated strong to severe thunderstorms will be possible with a Marginal Risk in place across much of southeast Michigan. - Higher than usual confidence in hot and humid conditions early next week. Temperatures into the 90s Monday and Tuesday with relatively high humidity will likely bring the highest heat indices we have seen so far this year. && .AVIATION... VFR conditions are expected through the rest of the forecast as both high and low clouds currently approach the area. Low clouds come from developing diurnal cumulus making its way northeast. Confidence is low on the final areal extent of this cloud deck before it dissipates later today. High cirrus from the west continue to make their way southeast through this evening and tonight. Ceilings will gradually lower overnight as a cold front moves closer to the area through Wednesday. No rain is expected to impact the CWA with this system, with ceilings reaching 5000 feet at their lowest tomorrow. For DTW/D21 Convection...Thunderstorms are not expected through the TAF period. DTW THRESHOLD PROBABILITIES... * Moderate for ceilings aob 5000 feet Wednesday afternoon. && .PREV DISCUSSION... Issued at 400 AM EDT Tue Jun 11 2024 DISCUSSION... Clear skies and calm winds overnight with the cooler airmass in place will allow for a somewhat chilly start to this morning. Observed morning temperatures at many locations are down into the 40s. Expecting mostly clear skies through the majority of today as an upper ridge axis passes over the Great Lakes today. A surface high pressure will also slide east of the state allowing for a moderating south-southwest wind. Expecting high temperatures to respond under full insolation through much of peak heating and climb into the low to mid 70s. Mid level trough will arrive on the heels of the exiting ridge axis tonight, which will likely be supporting upstream convection this evening along an advancing frontal boundary. Here in southeast Michigan, we will see increasing high clouds late today ahead of this activity. Precipitation associated with this frontal boundary is expected to weaken as enters western Michigan and encounters the resident dry lower levels. Any remnant high based showers continuing to drift east into southeast Michigan should struggle to reach the surface with these dry low levels. Will maintain a dry forecast for tonight given the underlying environment. The passing of this trough will mark the beginning of notable warming and increasing moisture trends Wednesday into the late week period. Strong mid/upper level westerly flow will drive 850 mb temperatures upwards of 16C into Michigan for Thursday. Dewpoints are also forecast to climb above 60 degrees with PWATs to around 1.50 inches. This will make for a hot and muggy day as daytime highs reach into the mid/upper 80s with 90 degrees achievable across the urban heat island of Detroit. This will also lead to moderate instability in place with MLCAPEs to around 1000 J/kg forecast during the afternoon ahead of a southward moving cold front. Deep layer shear will improve over southeast Michigan on the southern edge of a strong 70+ knot mid-level jet. The progged environment would be support a severe thunderstorm threat with any cluster of thunderstorms that develop ahead of the advancing front in this unstable environment. A Marginal Risk for severe weather is in place for Day 3. There is higher than usual confidence in hot and humid conditions early next week as a broad ridge builds across the central and eastern CONUS. This will also bring fairly high confidence in dry conditions for the weekend as return flow on the back of the passing ridge ushers in 850 mb temperatures reaching upwards of 20C during the early week period. Several ensemble members pointing towards temperatures into the 90s across all of southeast Michigan for Monday and Tuesday. The accompanied increase in moisture will likely result in the highest heat indices we have seen so far this year. MARINE... High pressure builds southeast into the Ohio Valley today promoting weak flow across the central Great Lakes. The ridge of high pressure will migrate eastward Wednesday offering a return-flow setup, veering winds southerly as the gradient slowly becomes more established into the second half of the week. A low pressure system is projected to arrive late Thursday into Friday which could support a period of Small Craft Advisory conditions with several opportunities for showers and thunderstorms. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...None. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....BC DISCUSSION...AA MARINE.......KGK You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.