


Area Forecast Discussion
Issued by NWS Grand Rapids, MI
Issued by NWS Grand Rapids, MI
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567 FXUS63 KGRR 071123 AFDGRR Area Forecast Discussion National Weather Service Grand Rapids MI 723 AM EDT Sat Jun 7 2025 .KEY MESSAGES... - Upper Low Brings Some Rain Early Next Week && .DISCUSSION... Issued at 311 AM EDT Sat Jun 7 2025 One more day of fair weather before rain chances increase on Sunday in advance of a vigorous upper low moving across the Great Lakes region. Before then...there is a slight chance of rain across the far southern zones tonight as a sfc low tracks across the Ohio Valley. The upper low approaches on Sunday with an axis of positive vorticity advection and upper level divergence moving through in the afternoon and evening. Thunder potential is limited by marginal instability with forecast soundings showing convective inhibition persisting through the afternoon. A secondary area of differential positive vorticity advection associated with the core region of the upper low moves in by Monday afternoon and combines with deeper moisture and steepening lapse rates/instability to bring a stronger diurnal enhancement of showers and thunderstorms in the afternoon and evening. The low moves out late Tuesday with fair weather returning for Wednesday. && .AVIATION /12Z TAFS THROUGH 12Z SUNDAY/... Issued at 723 AM EDT Sat Jun 7 2025 VFR conditions should prevail through tonight, although some light haze could persist through the morning at AZO and JXN. Winds will be light, generally below 8 knots. && .MARINE... Issued at 114 AM EDT Sat Jun 7 2025 Winds and waves are expected to be relatively calm through the middle of next week with winds less than 20 knots and waves 3 feet or less. && .GRR WATCHES/WARNINGS/ADVISORIES... MI...None. MARINE...None. && $$ DISCUSSION...Ostuno AVIATION...Ostuno MARINE...Ostuno