Area Forecast Discussion
Issued by NWS Detroit/Pontiac, MI
Issued by NWS Detroit/Pontiac, MI
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612 FXUS63 KDTX 150353 AFDDTX Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1153 PM EDT Tue May 14 2024 .KEY MESSAGES... - High pressure brings mainly dry weather and near normal temperatures for Wednesday. - Scattered to numerous showers and possible embedded thunderstorms return Thursday night and Friday. - Warming temperatures to close out the work week and carry through the weekend, when highs likely reach into the lower 80s on Sunday. && .AVIATION... Mid/upper clouds will persist across the area around low pressure circulation to the southwest. A lobe of this low will pivot closer to the region overnight with cigs 4-6kft thickening into I-94 and possibly KPTK. There is some chance of MVFR cigs. Lower VFR cigs will be erode/pivot away from area by midday Wednesday, and expect gradual clearing from north to south into the end of the forecast. Northeast winds will prevail throughout the forecast. For DTW/D21 Convection...Thunderstorms are not expected during this forecast period. DTW THRESHOLD PROBABILITIES... * Low confidence in cigs aob 5000 feet late tonight into Wednesday morning. && .PREV DISCUSSION... Issued at 324 PM EDT Tue May 14 2024 DISCUSSION... 700 MB moisture axis (5.5 g/kg of specific humidity)/right entrance upper level jet forcing triggering showers around M-46 to Saginaw Bay finally waning as low level northeast dry air also continues to undercut. Upper level low over the western Ohio Valley with associated low along the Ohio River, sliding east through tomorrow, with 500 MB ridge axis (568-570 DAM) building over the Central Great Lakes by Wednesday evening. Higher low level moisture content and still backed low level southeast flow this evening near the southern Michigan border will support a chance of light showers up to the I- 94 corridor, with a slight chance of weak thunderstorm right near the border. But otherwise, the low level dry air will continue to make further inroads tonight as low level northeast winds increase further. Still just enough residual moisture and modest cold advection around tomorrow to support decent amount of clouds, but highs still likely making a run aoa 70 degrees south of I-69, farther removed from the cool flow off Lake Huron. Upper level energy over the northern Rockies to get booted off to the east-northeast as 140 knot upper level jet tracks through southern British Columbia. Lead height fall center to track through Minnesota Wednesday night-Thursday, but additional weaker height falls/weak surface reflection to track through Central Great Lakes on Friday, supportive of unsettled/chance of rain showers to end the work week with the isentropic ascent/moisture advection. Marginal instability and modest instability will promote a slight chance of non-severe thundestorms as well. Large upper level ridge off the Pacific Northwest coast will sink south and become more west-east elongated, with some of the warm air over the Central Rockies breaking off and arriving over the Weekend, as 850 MB temps progged to exceed 15 C by Sunday, supportive of lower 80s for highs with favorable southwest winds. MARINE... Shower chances will remain possible into the early evening as high pressure continues to build in over the northern Great Lakes and pushes the frontal boundary south. There will continue to be a chance for rain and thunder overnight into Wednesday, mainly over Lake Erie, as low pressure moves eastward across the Ohio Valley. This low pressure system will reinforce northeast flow across all of the Great Lakes, building wave heights into Saginaw Bay and across the Lake Huron shoreline on Wednesday. Small Craft Advisories may be needed across Saginaw Bay and portions of the Lake Huron shorelines given wave heights building slightly above four feet. High pressure will continue to settle in over the Great Lakes on Thursday, relaxing wind speeds and subsequently wave heights. && .DTX WATCHES/WARNINGS/ADVISORIES... MI...None. Lake Huron...Small Craft Advisory from 8 AM to 8 PM EDT Wednesday for LHZ421-422. Small Craft Advisory from 4 PM to 11 PM EDT Wednesday for LHZ443. Lake St Clair...None. Michigan waters of Lake Erie...None. && $$ AVIATION.....DG DISCUSSION...SF MARINE.......SS You can obtain your latest National Weather Service forecasts online at www.weather.gov/detroit.