Area Forecast Discussion
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