250
FXUS63 KGRR 141815
AFDGRR
Area Forecast Discussion
National Weather Service Grand Rapids MI
215 PM EDT Thu May 14 2026
.KEY MESSAGES...
- Notable Warmup Into Next Week
- Several Chances of Showers and Storms Friday Night into Next Week,
Some May Be Strong to Severe
&&
.DISCUSSION...
Issued at 213 PM EDT Thu May 14 2026
- Notable Warmup Into Next Week
A substantial warmup is underway with 850 mb temps climbing well
into the teens by Monday. Some uncertainty exists in Saturday`s
temperature given the likely presence of an MCV driving
shower/thunderstorm potential Saturday and more extensive resulting
cloud cover. However, increasing south/southwest flow will support
highs well into the 80s, perhaps approaching 90 in some places.
Combined with dewpoints in the 70s, early next week will feel
downright summer-like. Even once the cold front moves through next
week, warm conditions continue with highs in the 70s.
The one caveat to this however is that we may see frost develop
overnight, especially across our traditional cold spots across our
northeastern CWA, depending on how fast clouds move in. If clouds
are slow to move in and temperatures fall faster, overnight lows
could fall into the mid 30s. Confidence is not high enough to go
with a Frost Advisory, but this will be monitored.
- Several Chances of Showers and Storms Friday Night into Next Week,
Some May Be Strong to Severe
Several chances for showers and thunderstorms exist between Friday
Night and mid-next week, with some questions as to the exact
evolution of this pattern.
Starting with Friday Night/Saturday, a mid-level MCV looks to
support the potential for showers and thunderstorms across the area,
with a second chance possible later Saturday near I-94 as a warm
front noses north, with greater precipitation coverage south of the
area.
Attention then turns to early next week as a low pressure system
strengthens across the Plains with a warm front surging north across
the area. With MUCAPE aoa 1000 J/kg and PWATs climbing north of 1.5
inches increasing chances for showers and thunderstorms. Cannot
completely rule out a stronger storm, but wind fields are weak, with
deep layer shear around 30 knots, keeping the risk low.
The greatest concern at this time is Monday where we currently sit
in a Day 5 Slight Risk from the Storm Prediction Center. Dewpoints
surging to near 70 with a 40-50 knot LLJ by Monday evening is
synoptically supportive of the potential for strong to severe
thunderstorms. However, timing of forcing remains uncertain, with
the better threat expected off to our west. This matches what ML
guidance from the GEFS/EPS suites has been indicating for several
days. Thus, what time the storms arrive and by extension what
environment exists for them when they do is uncertain and will
become clearer over the next few days. The other concern is the fact
that mid-level flow appears to be particularally weak, with the mid-
level jet displaced west. This will limit the magnitude of deep
layer shear available for these storms.
Then, the pattern becomes more uncertain Monday Night into early
next week. There is a trend in guidance that the strong ridging in
place struggles to dislodge, preventing a cold front from crossing
the area until later Tuesday. If this happens, strong to severe
thunderstorms would be possible once again as diurnal heating builds
instability ahead of the front. This reflects the ECMWF/AI-GFS/AI-
ECMWF consensus. On the other hand, the GFS leads the pack of
guidance that drives the cold front through Monday Night, putting us
in a post frontal environment with little risk for severe
thunderstorms Tuesday.
&&
.AVIATION /18Z TAFS THROUGH 18Z FRIDAY/...
Issued at 129 PM EDT Thu May 14 2026
VFR conditions will dominate the pattern over the next few days.
There will some partly cloudy skies but nothing substantial.
Winds will go calm this evening and then mix out out of the south
after sunrise. Gusty winds out of the south to southwest are
expected at all TAF sites tomorrow after 15Z.
&&
.MARINE...
Issued at 213 PM EDT Thu May 14 2026
Conditions become hazardous to Small Craft starting mid morning on
Friday as southerly flow strengthens. North of Holland,sustained
winds to 20 knots, with gusts as high as 30 knots possible near Big
and Little Sable Points, will drive 3-6 foot waves across the
nearshore waters. A Small Craft Advisory will be issued from mid
Friday morning through early Saturday morning. South of Holland, the
wind field is weaker, so combined with the warm air advection regime
limiting gust potential, confidence in more than isolated gusts
reaching advisory criteria is low. In coordination with neighbors,
will not issue a advisory south of Holland at this time. Winds are
then lighter for the weekend, with the potential for fog over the
waters as higher dewpoints surge into the region.
&&
.FIRE WEATHER...
Issued at 213 PM EDT Thu May 14 2026
Elevated fire danger is likely Friday, particularally along and
north of M46 east of US131. Gusty southwest winds to 25-30 mph along
with MinRHs falling in the low to mid 30s will drive elevated fire
weather conditions.Land management partners report that fuels are
drying quickly given little rain over the last day adding to the
concerns.
&&
.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
MARINE...Small Craft Advisory from 9 AM Friday to 5 AM EDT Saturday for
LMZ846>849.
&&
$$
DISCUSSION...Thomas
AVIATION...Ceru
MARINE...Thomas
FIRE WEATHER...Thomas
NWS GRR Office Area Forecast Discussion
