Special Weather Statement, NWS Grand Rapids, MI

Area Forecast Discussion
National Weather Service Grand Rapids MI
339 PM EDT Mon Jun 28 2021

LATEST UPDATE...
Synopsis/Discussion/Marine

.SYNOPSIS...
Issued at 339 PM EDT Mon Jun 28 2021

- Thunderstorm threats both Today and again on Tuesday

- Upper trough in place mid week to cooler weather with showers

- Warmer and drier into the Sunday and Monday time frame

&&

.DISCUSSION...(This evening through next Monday)
Issued at 339 PM EDT Mon Jun 28 2021

- Thunderstorm threats both Today and again on Tuesday

The threat for strong to severe thunderstorms exist both this
afternoon and evening and again Tuesday afternoon and evening. A
warm front has nudged northward to near I-96 this afternoon and
showers and storms will be fairly prevalent near and south of it
through 1000pm. Deep layer shear is marginal for severe weather,
but instability has built to solid levels into the 2,000 to
3,000 J/KG range. Damaging winds associated with wet microbursts
would be the most likely chance at severe weather this afternoon
and evening.

Pattern remains relatively close to the same on Tuesday with the
forecast area in the warm sector between a weak warm front to the
north and a weak cold front to the west. Instability will be
similar, but the difference on Tuesday will be a stronger mid
level wind up towards 50 knots. Shear will be a bit better and
storm organization will be better as well. A better chance at some
damaging winds tomorrow afternoon and evening.

Same air mass is in place so locally heavy rain is possible. It
will not be widespread enough to significantly affect the rivers,
but we could certainly be looking at Flood Advisories both today
and tomorrow.

- Upper trough in place mid week to cooler weather with showers

The pattern shifts into the middle of the week as an upper trough
moves our direction and pivots overhead from the Northern Plains.
We will turn a bit more showery into Wednesday and Thursday. The
upper trough moves through Thursday and Thursday night. Friday and
Saturday we begin to dry out with the trough moving east and north
flow setting up.

- Warmer and drier into the Sunday and Monday time frame

Late in the weekend and into early next week the western ridge
makes a run at the Great Lakes, losing much of its amplitude. We
should be dry Sunday into Monday and turning warmer. 850mb
temperatures support very warm conditions trending towards +21C
into Monday. This would support highs trending to around 90F.

&&

.AVIATION...(For the 18Z TAFS through 18Z Tuesday afternoon)
Issued at 137 PM EDT Mon Jun 28 2021

Our main concerns with the 18z forecasts are initially storm
potential this afternoon/evening, and then fog/stratus overnight.

A few showers have already developed down along I-94 as of 1730z.
We expect additional development through the afternoon, with the
showers growing into thunderstorms soon. It may take a little long
for KGRR and KMKG being further north away from the warm front.
KMKG has a good chance of not even seeing a storm with the
stabilizing influence of Lake Michigan and an onshore wind. The
storm potential will linger until 23-00z, with the best chance and
tempo group roughly from 19-23z. IFR conditions are likely under
any shower/storm, and have indicated this in the tempo group.

There does look to be a chance of some fog and stratus tonight
with lighter winds at the surface and a moist boundary layer. KMKG
may have both with a flow off of the lake. We can not rule out a
few showers overnight with another possible wave moving through.

The fog/stratus will dissipate by mid Tuesday morning. Showers and
storms will be possible/likely again Tuesday afternoon. Those
should be after the end of this forecast period however.

&&

.MARINE...
Issued at 339 PM EDT Mon Jun 28 2021

Main concern over the course of the next two days will be marine
dense fog. Higher dew point air will advect out over Lake Michigan
tonight into Tuesday. Confidence is not high enough to roll with a
marine dense fog advisory at this time. We will be monitoring
webcams along the lakeshore.

Conditions are expected to remain below Small Craft and Beach
Hazards Advisory criteria for the next several days at least. We
will be in a typical southwest flow for summer over the next
couple of days. Winds will be southwest at 5 to 15 knots, with
some potential for gusts to 20 knots at times. Nothing that will
push waves anywhere close to 4 feet though. Waves are actually
forecast to be 2 feet or less through Wednesday.

Winds shift to the northwest behind a cold front for the Wednesday
and Thursday time frame, but it does not appear that they will be
strong enough to reach criteria for SCA/BHS.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...None.
LM...None.
&&

SYNOPSIS...Duke
DISCUSSION...Duke
AVIATION...NJJ
MARINE...Duke

Hazardous Weather Outlook
National Weather Service Grand Rapids MI
117 PM EDT Mon Jun 28 2021

MIZ037>040-043>046-050>052-056>059-064>067-071>074-290845-
Mason-Lake-Osceola-Clare-Oceana-Newaygo-Mecosta-Isabella-Muskegon-
Montcalm-Gratiot-Ottawa-Kent-Ionia-Clinton-Allegan-Barry-Eaton-
Ingham-Van Buren-Kalamazoo-Calhoun-Jackson-
117 PM EDT Mon Jun 28 2021

This hazardous weather outlook is for portions of southwest Lower
Michigan.

.DAY ONE...This Afternoon and Tonight

Scattered thunderstorms are expected this afternoon and evening
between roughly 200pm and 1000pm. All storms today will contain
locally heavy rain and lightning, with the strongest storms capable
of producing damaging wind gusts and small hail. The possibility of
flooding exists where any rainfall occurs today given the saturated
soils.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

A chance of severe thunderstorms exists Tuesday afternoon and
evening as well. Damaging winds are the primary severe hazard. Where
the storms persist...excessive rain will be possible...which could
lead to an increase/return of the small stream and urban flooding.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

LMZ844>849-290845-
St Joseph to South Haven MI-South Haven to Holland MI-
Holland to Grand Haven MI-Grand Haven to Whitehall MI-
Whitehall to Pentwater MI-Pentwater to Manistee MI-
117 PM EDT Mon Jun 28 2021

This hazardous weather outlook is for portions of southwest Lower
Michigan.

.DAY ONE...This Afternoon and Tonight

Isolated thunderstorms with gusty winds will be possible. Patchy
dense fog could occur as well early.

.DAYS TWO THROUGH SEVEN...Tuesday through Sunday

Thunderstorms will be possible into Tuesday night. Cloud to water
lightning strikes and gusty winds are the main forecasted hazard.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GRAND RAPIDS MI
144 PM EDT MON JUN 28 2021

..TIME...   ...EVENT...      ...CITY LOCATION...     ...LAT.LON...
..DATE...   ....MAG....      ..COUNTY LOCATION..ST.. ...SOURCE....
            ..REMARKS..

0423 PM     TORNADO          3 WNW LOWELL            42.95N 85.39W
06/26/2021                   KENT               MI   NWS STORM SURVEY

            EF-0 WITH PATH LENGTH 0.6 MILES. TREES AND
            LIMBS WERE SNAPPED FROM BENNETT ST AND
            CUMBERLAND AVE TO VERGENNES ST EAST OF
            CUMBERLAND AVE.

&&

Special Weather Statement
National Weather Service Grand Rapids MI
400 PM EDT Mon Jun 28 2021

MIZ057-058-282030-
Ionia-Kent-
400 PM EDT Mon Jun 28 2021

...A STRONG THUNDERSTORM WILL AFFECT SOUTHEASTERN KENT AND WEST
CENTRAL IONIA COUNTIES...

At 400 PM EDT, a thunderstorm was located 6 miles southwest of
Lowell, or near the Grand Rapids Airport, moving northeast at 20 mph.

Winds in excess of 40 mph are possible with this storm.

Locations impacted include...
Lowell...              Ada...                 Murray Lake...
Alto...                Cascade...

Frequent cloud to ground lightning is occurring with this storm.
Lightning can strike 10 miles away from a thunderstorm. Seek a safe
shelter inside a building or vehicle.

LAT...LON 4305 8546 4304 8517 4284 8531 4288 8554
TIME...MOT...LOC 1959Z 212DEG 17KT 4288 8546

CAS