606
FXUS63 KGRR 232341
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
741 PM EDT Thu Apr 23 2026
.KEY MESSAGES...
- Slight chance of showers/storms this afternoon/evening, better
chance Friday
- Chance of storms Monday
- Cooler next week
&&
.DISCUSSION...
Issued at 224 PM EDT Thu Apr 23 2026
- Slight chance of showers/storms this afternoon/evening, better
chance Friday
There`s been a surge of moisture today across the cwa behind a
warm front and surface dewpoints are near 60 in many locations.
Additionally, a weak short wave is riding over the upper ridge
across the state. As such, some of the CAMs are pointing toward
some isolated convection developing later this afternoon after 3-4
pm, mainly southeast of Grand Rapids. SBCAPE is progd to increase
to 1000-1500 j/kg this afternoon. Any storms that develop,
however, are expected to be sub-severe as bulk shear is progd to
remain below 20 knots which will limit storm organization.
The next chance of storms will arrive Friday when a cold front
moves through the region. RRFS-EMC progs point toward decaying
showers/storms moving across the cwa Friday morning with a
potential refiring Friday afternoon. The clouds and lingering
precipitation Friday morning may keep a lid on instability through
much of the cwa Friday. CAMs show this with storms redeveloping
east of Lansing Friday afternoon where morning convection didn`t
have as much of an influence on atmospheric instability.
Nevertheless, CAMs also show some redevelopment along the cold
front after 20z east of US-131, so there`s likely to be some
recovery after the morning precipitation with a likelihood of
strong storms southeast of the cwa.
- Chance of storms Monday
After a weekend featuring partly to mostly sunny skies, highs in
the mid 60s and dewpoints in the 40s, the next system will arrive
Monday night and Tuesday. The next cold front will move in Monday
night. SBCAPE is progd near 500 j/kg early Tuesday morning. Thus
storms are possible, but the late night arrival will diminish
chances for severe storms.
- Cooler next week
Once the cold front moves through Tuesday, h8 temperatures will
fall from 12c Tuesday to 0c Wednesday morning. That will set the
stage for cooler weather mid to late week. We`ll see highs in the
mid 50s Wednesday and Thursday. Surface high pressure will build
in from the northwest, but zonal flow aloft will likely supply
some high clouds.
&&
.AVIATION /00Z TAFS THROUGH 00Z SATURDAY/...
Issued at 741 PM EDT Thu Apr 23 2026
VFR conditions will continue into Friday morning then MVFR is
possible in the late morning and afternoon as rain showers move in
from the west. There could be an isolated thunderstorm in the
afternoon but coverage is low enough that it has been left out of
the forecast for now. South winds around 10 knots overnight will
go southwest on Friday afternoon.
&&
.MARINE...
Issued at 224 PM EDT Thu Apr 23 2026
High pressure overhead is keeping wind and waves below advisory
criteria. South winds will increase Friday ahead of the next cold
front and waves will build to 2 to 4 feet north of Grand Haven.
It`s not out of the question that a small craft advisory may be
needed Friday, but confidence is`t high enough to issue yet.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...04
AVIATION...Ostuno
MARINE...04
NWS GRR Office Area Forecast Discussion
