693
FXUS63 KGRR 151903
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
303 PM EDT Sun Mar 15 2026
.KEY MESSAGES...
- Rain and Thunder tonight with a low threat for Severe storms
- Much Colder with Lake effect Snow on Monday into Tuesday
&&
.DISCUSSION...
Issued at 303 PM EDT Sun Mar 15 2026
- Rain and Thunder tonight with a low threat for Severe storms
We have hoisted a Winter Weather Advisory for the western two rows
of counties and extended and expanded the Wind Advisory.
Temperatures across Lower Michigan this afternoon range from 30
degrees at CAD to near 70 at the MI-IND border. Despite over 50
knots of deep layer shear, the severe weather threat is limited by
a lack of instability as seen by forecast and observed soundings.
A first batch of convection has weakened as it moved into a more
stable environment this afternoon with dew points still in the 30s
down to I-94. The dew points across the southern zones should
recover to the lower 50s based on upstream obs, but the threat for
severe appears to be limited to isolated wind gusts this evening
across the far southern/southeast zones.
Sfc low tracks through central Lower Michigan with cold advection
beginning after midnight and synoptic winds expected to begin or
continue gusting to 40 to 50 mph for all zones by daybreak.
- Much Colder with Lake effect Snow on Monday into Tuesday
Strong CAA continues all day Monday and temperatures will drop
into the teens by evening. Model soundings show inversion heights
around 8 kft and strong northwest flow with snow showers
penetrating far inland. With temperatures well below freezing,
blowing snow will reduce visibilities through Tuesday morning.
The snow showers will diminish on Tuesday as the upper trough axis
shifts east surface high pressure builds in.
&&
.AVIATION /18Z TAFS THROUGH 18Z MONDAY/...
Issued at 141 PM EDT Sun Mar 15 2026
We`ll see a little bit of everything during the period. Light rain
showers will begin the TAF period. Strong winds aloft will create
LLWS. Thunderstorms developing along a cold front will move
across the terminals late this afternoon and early evening. IFR
cigs will develop once the cold front moves through. As colder air
advects over the region, rain showers will transition to snow
showers. Strong winds will continue with a veering to the WNW and
create some blowing snow too. Accumulations are possible Monday at
MKG/GRR.
&&
.MARINE...
Issued at 303 PM EDT Sun Mar 15 2026
No changes to the Gale and Heavy Freezing Spray Warnings. After a
line of showers and thunderstorms go through this evening the winds
will go northwest on Monday with occasional gusts to 40 knots.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Winter Weather Advisory from 8 AM Monday to 11 AM EDT Tuesday
for MIZ037-038-043-044-050-056-057-064-065-071-072.
Wind Advisory until 11 PM EDT Monday for MIZ039-040-045-046-051-
052-058-059-064>067-071>074.
MARINE...Gale Warning until 5 AM EDT Tuesday for LMZ844>849.
Heavy Freezing Spray Warning from 8 AM Monday to noon EDT
Tuesday for LMZ844>849.
&&
$$
DISCUSSION...Ostuno
AVIATION...04
MARINE...Ostuno
NWS GRR Office Area Forecast Discussion
