Comstock, Michigan Weather Forecast Discussion

553
FXUS63 KGRR 141133
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
733 AM EDT Sun Sep 14 2025
.KEY MESSAGES...
- Dry weather most of this week
- Chance of showers and thunderstorms starting Friday
&&
.DISCUSSION...
Issued at 304 AM EDT Sun Sep 14 2025
- Dry weather most of this week
Flow over the eastern CONUS will resemble a Rex block pattern (ridging
with the polar jet and troughing with the subtropical jet) beginning
early this work week. Being a blocky pattern, it should persist
for several days. And, given rather sharp ridging aloft in our
vicinity, we can expect dry and abnormally warm maximum temperatures.
We are now looking at upper 80s Wednesday/Thursday, and this
could easily be exceeded on Thursday especially.
- Chance of showers and thunderstorms starting Friday
Model guidance has been fairly consistent with bringing an upper
shortwave trough to the western Great Lakes, which will bring more
seasonal temperatures along with a chance for showers and thunderstorms.
Predictability is limited given weak and poorly phased flow aloft,
especially regarding precipitation chances. QPF is broad-brushed
areally and temporally (across multiple days including the weekend)
to illustrate the uncertainty. But in reality, precipitation may
be quite episodic and spotty with any accumulations not expected
to make much of a dent in our recent precipitation deficits.
&&
.AVIATION /12Z TAFS THROUGH 12Z MONDAY/...
Issued at 733 AM EDT Sun Sep 14 2025
There is a low probability of MVFR visibility restrictions in BR
before 13Z. This will be followed by a prolonged period of VFR
conditions. A broken cloud layer above 5000 feet is currently
being reported at some observation sites. However, this layer is
expected to become scattered areawide later this morning. Winds
will be light and predominantly easterly in direction.
&&
.MARINE...
Issued at 304 AM EDT Sun Sep 14 2025
Winds and waves are expected to remain below hazardous levels. As
noted previously, the larger scale flow will generally be light
and offshore. However, large diurnal temperature swings are
expected over Lower Michigan and this will promote an active
lake/land breeze diurnal cycle.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...TJT
AVIATION...TJT
MARINE...TJT

NWS GRR Office Area Forecast Discussion