Area Forecast Discussion
Issued by NWS Grand Rapids, MI

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FXUS63 KGRR 091155

Area Forecast Discussion
National Weather Service Grand Rapids MI
755 AM EDT Fri Jun 9 2023


.SHORT TERM...(Today through Saturday)
Issued at 345 AM EDT Fri Jun 9 2023

Little in the way of concern in the Today through Saturday period.
Mainly dry weather is forecast throughout, with clear to partly
cloudy skies today and tonight. Clouds will be on the increase on
Saturday in advance of an upper trough diving south into the area
in northerly upper flow. The SREF has 20-40 pops across Central
Lower and we have gone with 20-30 percent pops in the late
afternoon and evening. Bulk of the more active weather is beyond
the short term.

The HRRR smoke model shows very much the same story as the last
couple of days. Plenty of vertically integrated smoke in place
through the course of the day today, so the sky will be a bit
opaque at times. The near surface smoke has a push into the area
early this morning, lingering through the morning and slowly
sinking south in the afternoon. Bottom line...much of the same as
we have seen lately. Not expecting major restrictions to surface
visibility as the magnitude of the smoke in Western Lower
Michigan is not overly high.

.LONG TERM...(Saturday night through Thursday)
Issued at 345 AM EDT Fri Jun 9 2023

- Chance for showers Saturday night through Tuesday -

A significant wx pattern change will occur Sunday through Tuesday as
a closed upper low meanders slowly across our region. This system
will bring cooler conditions and fairly extensive cloud cover and
occasional showers. Shower potential will be enhanced from time to
time by several vort maxes which will rotate around the upper low.
Convective potential looks quite low given weak instability.

Latest GEFS/ECMWF ensembles support potential for at least a half an
inch of rainfall Sunday through Tuesday. However considerable
variability in rainfall across our area is expected. Rainfall
amounts could range from under a quarter of an inch in some spots to
around two inches or greater as shown by some of the deterministic
medium range guidance where rain showers are heaviest/most

- Fair weather returns Wednesday and Thursday -

The upper low will finally move east of our region by Wednesday.
Fair wx will return Wed/Thur along with a moderating trend of temps
as an upper ridge begins to build in from the west in this time


.AVIATION...(For the 12Z TAFS through 12Z Saturday morning)
Issued at 756 AM EDT Fri Jun 9 2023

VFR weather is forecast throughout the TAF period. There may be a
bit of cumulus that develops today with bases around 5,000 feet,
but did not include that in the TAFs at this time. Winds will
become northwest at 5-10 knots today.


Issued at 345 AM EDT Fri Jun 9 2023

No significant marine concerns over the next couple days with a
mainly light wind regime in place. The next time frame of concern
will come on Sunday as northerly winds increase as a low develops
and then traverses the Southern Great Lakes. We are at least
looking at Small Craft Advisory conditions from later on Sunday
into Monday as winds and waves build. The NAM looks too deep with
the low, but it would suggest even Gales are possible.


Issued at 345 AM EDT Fri Jun 9 2023

We have opted to not issue a Red Flag Warning today as conditions
look quite marginal in regard to one of the weather factors,
namely the wind. Fire danger remains high to extreme, but winds
look quite light and therefore fire spread would not be as great.
We still have highs in the mid to upper 70s with RH values that
will dip to around 25 percent. Again, with regard to the wind,
this will likely be the lightest wind field of the last several
days. HRRR winds are generally 10 knots or less today across the
coniferous forested counties of our northern couple rows across
Central Lower Michigan.




LONG TERM...Laurens
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