028
FXUS63 KGRR 041900
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
300 PM EDT Mon May 4 2026
.KEY MESSAGES...
- Marginal Risk Severe Tonight
- Frost/Freeze Potential Tuesday and Wednesday Nights
&&
.DISCUSSION...
Issued at 258 PM EDT Mon May 4 2026
- Marginal Risk Severe Tonight
Cold front sags south to meet modest moisture return overnight
with some isolated storms capable of producing hail and enough
DCAPE thanks to dry subcloud layer for strong gusty winds to reach
the surface with any descending precip cores. Severe threat
diminishes late tonight as the front clears the southern zones.
- Frost/Freeze Potential Tuesday and Wednesday Nights
Cold airmass behind the front with cloudy cool and showery
conditions lingering across the southern zones on Tuesday. SOme
clearing is possible across the north Tuesday night which would
allow frost and freezing conditions, so Frost/Freeze headlines
will probably be needed across the northern counties. Wednesday
night could see more clearing and thus colder temperatures.
A clipper type low moves through Thursday and model soundings
show wet-bulb zero heights not far off the surface across the
northern zones, so graupel or wet snow is possible there.
Frost/Freeze potential lingers into next weekend and beyond as a
cold northwest flow regime continues.
&&
.AVIATION /18Z TAFS THROUGH 18Z TUESDAY/...
Issued at 158 PM EDT Mon May 4 2026
Prevailing VFR expected over the next several hours with few to
scattered cumulus bases around 6,000 feet. Winds will be gusty
from the southwest. Scattered showers and thunderstorms may
develop between AZO and JXN after 22 Z, followed by a 2 or 3 hour
period of showers and some embedded thunderstorm cells in the
vicinity of a cold front sweeping through the whole area from
west to east between 00 and 06 Z. Any thunderstorms will be
capable of microbursts and outflow resulting in gusty winds up to
40 or 50 knots and LLWS.
&&
.MARINE...
Issued at 258 PM EDT Mon May 4 2026
No changes to the SCA. Winds and waves will diminish behind the
cold front late tonight and on Tuesday. Fairly tranquil conditions
through Wednesday.
&&
.FIRE WEATHER...
Issued at 258 PM EDT Mon May 4 2026
Issued a RFW as RH is down to around 20 percent and winds are
gusting to 35 mph. Higher dew points will be spreading north this
afternoon and evening as temperatures and wind gusts diminish.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Red Flag Warning until 7 PM EDT this evening for MIZ038>040-
044>046-051-052-058-059.
MARINE...Small Craft Advisory until 11 PM EDT this evening for LMZ844>849.
&&
$$
DISCUSSION...Ostuno
AVIATION...CAS
MARINE...Ostuno
FIRE WEATHER...Ostuno
NWS GRR Office Area Forecast Discussion
