582
FXUS63 KGRR 160700
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
300 AM EDT Fri Oct 16 2026
.KEY MESSAGES...
- Wet, windy, and colder today; Frost tonight
- Tranquil weather for Sat and beyond with moderating temperatures
&&
.DISCUSSION...
Issued at 300 AM EDT Fri Oct 16 2026
- Wet, windy, and colder today; Frost tonight
No surprises thus far with the ongoing system over the area this
morning. The main batch of rain showers came through earlier with
the nose of the strong low level jet passing through. This has
exited east, and the initial cold front has just about cleared the
area to the east as of 230 am.
Plenty of forcing remains and continues to bring showers to the area
as the large northern stream trough is now approaching with large
scale upper divergence ahead of it moving over the area. In
addition, the RRQ of a 140 knot upper jet will aid in the rain
development this morning.
We continue to watch the secondary front/cold conveyor belt that is
expected to drop through from mid morning into the early afternoon
hours. This will bring more showers to the area, highly concentrated
near the lakeshore where cold enough low level air and cyclonic
flow/cold air aloft moves in. We continue to see good signs that a
few storms will be possible close to the lakeshore with this
feature due to the strong instability over the lake feeding this.
The flow will quickly shift to become more from the NNE behind this
front. We will see the gusty winds behind this, which look to peak
around 40 mph for a brief time. No wind advisory looks to be needed
at this time. Even along the lakeshore where it will be slightly
offshore. We will see a few pop up rain showers continue to be
possible inland, but nothing looks to be organized.
Once we lose the diurnal boost of the instability, the threat for
showers will drop significantly or end. The upper cyclonic flow will
exit the area after 00z, allowing ridging to build in through the
night. Winds will be up in the evening, but will settle down quite a
bit overnight. We could decouple well at that time, and see a fair
amount of frost for much of the interior. A frost advisory may be
needed, and can be issued by the day shift.
- Tranquil weather for Sat and beyond with moderating temperatures
Confidence continues to increase that we will see an extended period
of tranquil weather from Saturday through the upcoming week, and
likely beyond.
The increased confidence comes as we see the pattern expected to be
even more amplified than previously thought, and the favorable
weather under the upper ridge expected to be over our region. The
upper trough/low to our west is expected to close off now and slow
up in trying to move east. This is likely at least partially due to
the closed low off of the east coast and upper ridge slowing down
the progression of the upper air flow over the CONUS.
The majority of the time, pops will be near zero with strong
subsidence overhead. There is a period on Thursday and Friday where
the ridge is temporarily flattened by energy over Canada. These
short waves will have no decent moisture to advect in, and little to
no moisture to start with.
Temperatures will start out cool on Saturday in the 50s with the
cool flow from Canada remaining in place immediately behind the
Friday system. We will see heights build, and a return flow advect
warmer air gradually over the area. We are likely to see
temperatures approach 70 by mid week, and stay mild through the end
of the week, with just a slight cool down with the ridge flattened
briefly.
&&
.AVIATION /06Z TAFS THROUGH 06Z SATURDAY/...
Issued at 153 PM EDT Fri Oct 16 2026
The first batch of rain has moved through the area ahead of a
front that is located near KLAN to KJXN at 0530z. A noticeable
wind switch is occurring with the front, and a brief increase in
wind gusts to about 35 knots. IFR remains dominate across the area
with pockets of MVFR. IFR will continue for a few more hours with
showers continuing with the next part of this system moving in.
Conditions will improve to MVFR this morning, but we could see
some IFR with another front moving through mid-morning to early
afternoon. This front could actually cause some storms at KMKG
with the instability over the lake.
Once the secondary front moves through this afternoon, winds will
shift to become from the NNW and gust to 30-35 knots. Conditions
will improve slowly to high end MVFR, and eventually VFR late this
afternoon and evening. Showers will tend to migrate closer to the
Lake Michigan shoreline. More cloud cover may hold at KLAN and
KJXN this evening with some clouds coming in from Lake Huron.
&&
.MARINE...
Issued at 300 AM EDT Fri Oct 16 2026
Everything looks to be on track with regards to headlines this
morning, so no changes are necessary at this time.
We have solid Small Craft Advisory conditions ongoing behind the
initial front that passed through around midnight. The Gales are
expected to arrive by noon with a secondary front dropping through
that will bring a nice cold surge with it. Solid Gales remain
expected, with a small chance of a brief Storm Force wind gust. Not
enough to need a Storm Warning.
Winds will steadily diminish then this evening as we see a sfc ridge
axis pass through. This will be short lived as another strong area
of gradient winds drops down over the area late Saturday through
most of Sunday. Those winds and waves will require another Small
Craft Advisory to be issued.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory until 11 AM EDT this morning for LMZ844>849.
Gale Warning from 11 AM this morning to 2 AM EDT Saturday for
LMZ844>849.
&&
$$
DISCUSSION...NJJ
AVIATION...NJJ
MARINE...NJJ
NWS GRR Office Area Forecast Discussion
