120
FXUS63 KGRR 201048
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
648 AM EDT Wed May 20 2026
.KEY MESSAGES...
- Dry weather through Thursday night with frost possible tonight
- Rain back in the forecast Friday into the weekend
- Warmer and mainly dry early next week
&&
.DISCUSSION...
Issued at 358 AM EDT Wed May 20 2026
- Dry weather through Thursday night with frost possible tonight
Surface high pressure will bring dry weather today through
Thursday night. Clouds will gradually erode today with partly
cloudy skies expected tonight. We may need a Frost Advisory
tonight across Central Lower Michigan, but after coordination with
other offices decided to hold off on the advisory/warning decision
until later today as there may be a good amount of high clouds
around yet which would affect low temperatures. In addition, there
is a fair amount of wind in the lowest 2,000 feet. A partly
cloudy day is expected on Thursday with mid and high clouds
streaming in from the west. It will be cooler than normal today
and Thursday with highs in the 50s and 60s today warming to the
60s on Thursday. Normal highs are around 70.
- Rain back in the forecast Friday into the weekend
Rain returns to the forecast on Friday and especially for Friday
night and Saturday. A shortwave trough aloft lifts from the
Southern Plains states into the Great Lakes for Friday night and
Saturday with an upper trough then swinging through on Sunday. A
healthy surge of moisture comes in on a low level jet Friday night
and Saturday which is when we should have the highest
concentration of showers and thunderstorms. This time frame will
essentially be affected by a warm front of sorts with a cold front
moving through on Sunday. Bottom line is the weather will be a bit
unsettled during this time.
- Warmer and mainly dry early next week
Warmer and drier weather is expected early next week with zonal
flow aloft trending towards ridging. At the surface, ridging will
be in place. High temperatures will be warming into the 70s to
near 80 degrees.
&&
.AVIATION /12Z TAFS THROUGH 12Z THURSDAY/...
Issued at 648 AM EDT Wed May 20 2026
There are some MVFR ceilings over portions of Lower Michigan
drifting south from I-96 at 11z. These ceilings should affect
most of the TAF sites this morning, with MKG being the exception.
By this afternoon we are expecting VFR weather to prevail which
will continue into tonight. North winds can be expected today at
7-12 knots. There will be occasional gusts into the 15-20 knot
range.
&&
.MARINE...
Issued at 358 AM EDT Wed May 20 2026
Our typical advancing high scenario presents itself today on the
first day of the Surf Zone Forecast season. A high building into
the Great Lakes from the northwest winds increase northerly winds
down the shoreline through an enhanced pressure gradient along the
lakeshore. The combination of the high building in and thermal
affects (troughing developing over the Lower Peninsula) due to a
thinning of the low clouds produces stronger winds down the
shoreline. The winds can be seen in the HRRR guidance. While we
are not expecting many swimmers today (buoy water temps are in the
lower 50s) we will still issue a Beach Hazard Statement as the
season has begun. A corresponding Small Craft Advisory will be in
effect as well, both running from 100pm into tonight. Winds go
offshore late tonight and into Thursday which will lead to
improving conditions.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement from 1 PM EDT this afternoon through
late tonight for MIZ056-064-071.
MARINE...Small Craft Advisory from 1 PM this afternoon to 2 AM EDT
Thursday for LMZ844>846.
&&
$$
DISCUSSION...Duke
AVIATION...Duke
MARINE...Duke
NWS GRR Office Area Forecast Discussion
