059
FXUS63 KGRR 241726
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
126 PM EDT Thu Sep 24 2026
.KEY MESSAGES...
- Dry and mild through the weekend
- Chance of rain late Tuesday/Wednesday
&&
.DISCUSSION...
Issued at 126 PM EDT Thu Sep 24 2026
- Dry and mild through the weekend
The blocking ridge over Ontario/Quebec continues to dominate our
weather and will through the weekend. Latest visible loop shows
clear skies over much of the cwa with some diurnal co over the
southern row...around the periphery of the Ohio Valley low. We
aren`t going to see much change for several more days as the
blocking pattern remains in place. Highs from the mid 60s to lower
70s Friday will gradually warm to highs in the lower to mid 70s by
Monday. Lows in the mid to upper 40s are expected each day.
- Chance of rain late Tuesday/Wednesday
The GFS has taken a turn toward the ECMWF late Tuesday and
Wednesday and now shows a northern stream wave moving across the
upper Midwest and knocking down the ridge. Concurrently, a
southern stream wave helps to develop a surface low in the
southern Plains. This result is that the cold front pushed across
the state by the northern wave gets hung up over the cwa late
Tuesday into Wednesday by the developing Plains low. This frontal
boundary then becomes quasi stationary and a focus for shower
development. Thus, confidence is fairly high that we`ll see
precipitation late Tuesday into Wednesday that may linger into
Thursday. ECMWF and GFS ensembles also show this. At this point,
the thunder threat looks low given weak instability.
&&
.AVIATION /12Z TAFS THROUGH 12Z FRIDAY/...
Issued at 644 AM EDT Thu Sep 24 2026
High confidence in VFR weather the next 24 hours. High pressure
will bring mainly clear skies and fair weather today. Some
FEW-SCT clouds around 5,000 feet are expected today with some
cirrus moving in tonight with BKN bases around 20,000ft. Winds
will be from the east today at 5-15 knots.
&&
.MARINE...
Issued at 126 PM EDT Thu Sep 24 2026
A high pressure ridge over the Great Lakes will continue to supply
the region with an easterly wind flow. That will push the highest
waves off shore. Given the light pressure gradient, even the waves
at the 5 mile point off shore will be at or below 3 feet. These
conditions will persist through the weekend.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...None.
&&
$$
DISCUSSION...04
AVIATION...Duke
MARINE...04
NWS GRR Office Area Forecast Discussion
