925
FXUS63 KGRR 251119
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
719 AM EDT Sat Apr 25 2026
.KEY MESSAGES...
- Quiet weather conditions today through Monday morning
- Showers and thunderstorms expected Monday night
- Mainly dry and cooler for the remainder of the work week
&&
.DISCUSSION...
Issued at 350 AM EDT Sat Apr 25 2026
- Quiet weather conditions today through Monday morning
Rain showers have moved east of the Lower Peninsula this morning
as a low treks southeast away from the Great Lakes. A northerly
push of wind in the wake of the low is bringing in low clouds
early this morning. We expect the clouds to peak in coverage this
morning and then gradually try to erode from west to east during
the midday and afternoon. HRRR soundings would speak to a more
pessimistic forecast though as a stout subsidence inversion is
seen with moisture trapped below. Would not be surprised to hang
on to some clouds through the entire day, especially towards JXN.
Dry weather is expected tonight through the rest of the weekend
with high pressure in control of the area weather at the surface.
Precipitation with our next system looks to hold off through much
of Monday. Temperatures will be near normal for this time of year.
- Showers and thunderstorms expected Monday night
Showers and storms are likely Monday night with some shower
activity lingering into Tuesday morning. The main focus for Monday
night is the chance for severe weather. The models lift a potent
looking upper shortwave into the Great Lakes region with
diffluence seen at 500mb indicative of the strength of the system.
Down at the surface a deepening low will lift through Wisconsin
which will bring a 50 knot low level jet into the area, which is
quite strong even by April standards. Speeds in the mid levels
are on the order of 60-70 knots. So, suffice it to say we will
have plenty of deep layer shear in place...near 50 knots. The
question remains how much instability we will have to work with as
the activity will be coming in during the night. Models suggest
we still may have 1,000 j/kg to work with. Given surface dew
points rise to around 60F and PWAT values increase to around 1.5
inches, our feeling is the instability in the GFS and ECMWF is
probably underdone. The NAM`s 1,000 to 2,000 j/kg looks more
likely. Given the CAPE / Shear parameter space we feel severe
weather is certainly possible. SPC`s day 3 outlook has us in a
marginal at this point in the southwest corner of the CWA. Could
see that expanding in coverage and possibly being bumped up a
category as we draw closer to Monday night. Given the moisture and
lift in play, we are looking at a locally heavy rain threat as
well. Half inch to one inch amounts look reasonable.
- Mainly dry and cooler for the remainder of the work week
We remain in broad upper troughing through the remainder of the
work week. Given a colder airmass and late April sun angles we
probably can`t rule out some diurnal showers each afternoon, but
the bulk of the time most areas will be dry from Tuesday afternoon
through Friday. Partly cloudy skies and temperatures sliding back
into the 50s for highs.
&&
.AVIATION /12Z TAFS THROUGH 12Z SUNDAY/...
Issued at 720 AM EDT Sat Apr 25 2026
Low clouds have spread over much of Southwest Lower Michigan as of
12z. Ceilings vary a few hundred feet either side of 1,000 feet
making both IFR and MVFR ceilings present. Through the course of
the morning we expect ceilings to scatter out across Western Lower
Michigan. Through the center of the state, LAN and JXN, we expect
the lower ceilings to persist into the afternoon. There is a
chance that the lower ceiling remain in place even into the
evening at JXN. Tonight VFR weather is expected at all sites.
&&
.MARINE...
Issued at 350 AM EDT Sat Apr 25 2026
Low pressure will pull away to the east of Lower Michigan today
resulting in north winds over Lake Michigan. 10-20 knot winds are
likely with a chance for slightly higher when looking at the mid
lake buoy BUFKIT site. We should be looking at 2-4 foot waves
today with the highest waves occurring from Grand Haven to the
south.
High pressure settles in for the rest of the weekend with winds
going off shore given our base of the high location. Winds and
waves will stay below Advisory levels tonight and Sunday. A strong
low will lift northward across Wisconsin on Monday resulting in an
increase in winds. Small Craft Advisory conditions are likely
Sunday night into Monday. We may touch gale force winds Monday
night.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...Duke
AVIATION...Duke
MARINE...Duke
NWS GRR Office Area Forecast Discussion
