870
FXUS63 KGRR 042316
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
616 PM EST Tue Nov 4 2025
.KEY MESSAGES...
- Mostly dry tonight, Rain Thursday night & Friday
- Colder with rain/snow showers Saturday-Monday
&&
.DISCUSSION...
Issued at 218 PM EST Tue Nov 4 2025
- Mostly dry tonight, Rain Thursday night & Friday
Latest visible loop shows quite a bit of mid clouds have developed
over the cwa in response to ongoing isentropic lift associated
with warm advection on the west side of the lake. The warm
advection is ahead of low pressure over the eastern Dakotas that
will move east across northern Lower Wednesday morning. Models
show these clouds persisting overnight.
The low will drag a cold a cold front through around 12z and
there`s a 15-20 percent chance of a shower or two north of M-46
late tonight/early Wednesday. Breezy conditions will develop
Wednesday in the wake of the front, but the cooler air won`t
arrive until Thursday when temperatures will top out around 50.
A deeper low will follow Thursday night and Friday. There`s more
moisture with this system and stronger dynamics with the trailing
short wave and we should see more rain (90-100 percent chance)
along the cold front Thursday night. QPF in the quarter to third
inch range will be common across the cwa.
- Colder with rain/snow showers Saturday-Monday
The next low in the wave train is expected Saturday night. Models
have trended a little farther south with the low and that`s
supported by the position of the upper wave across the Missouri
Valley. Additionally, the large upper low over Hudson Bay will
move south late in the weekend and early next week and send
additional short waves through the flow. Given the colder air in
place Saturday night (h8 temps in the -4 to -6c range), the
precipitation will likely be snow with some rain mixed in and some
accumulations may be possible. However it`s still too early to
pin down those details, but will certainly be watched.
Highs Sunday and Monday will be in the upper 30s and lows Sunday
night and Monday night around 20.
&&
.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/...
Issued at 616 PM EST Tue Nov 4 2025
VFR conditons will continue through the first part of the night
with cloud bases mainly in the 7-10kft range. At this time latest
trends suggest showers will stay north of the terminals. Starting
early Wednesday morning an advancing cold front will bring the
potential for MVFR ceilings to the terminals. Chances could start
as early as 10-12z with a better signal after 12z. Confidence
remains low in specific timing and extent given questionable
handling of ceilings by short range guidance. Low clouds will
begin to scatter out in the afternoon. Southerly winds are
expected tonight, with a period of LLWS as we decouple from the
winds aloft with 40 knot winds around 2kft. As the front arrives
late tonight, the cold air advection and better mixing will allow
gusts from the southwest, eventually becoming northwest by the
afternoon, to around 25 knots.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 8 AM EST Thursday for LMZ844>849.
&&
$$
DISCUSSION...04
AVIATION...Thomas
NWS GRR Office Area Forecast Discussion
