Beach Hazards Statement 5, NWS Grand Rapids, MI

Area Forecast Discussion
National Weather Service Grand Rapids MI
329 PM EDT Sat Jul 6 2019

LATEST UPDATE...
Synopsis/Discussion/Marine

.SYNOPSIS...
Issued at 329 PM EDT Sat Jul 6 2019

- Spotty showers/storms will continue this afternoon and evening
  south of I-96 with heavy downpours likely.

- Drier and less humid conditions are expected from Sunday through
  Tuesday.

- A cold front will sweep through the Great Lakes around the
  Wednesday timeframe, with calm weather returning thereafter.

&&

.DISCUSSION...(This evening through next Saturday)
Issued at 329 PM EDT Sat Jul 6 2019

The radar screen continues to fill in generally south of I-96 and
especially along I-94 at the overlap of MLCAPE of 1000-1500 J/kg
and a low- level frontal zone. We've seen a few more robust
updraft pulses over the past hour suggesting that gusty winds to
35-45 mph remain possible with the strongest thunderstorms in
addition of course to torrential rainfall and cloud-to-ground
lightning. We continue to monitor an MCV currently located near
Milwaukee slowly moving east/south east as well as broken mid-
level cloud cover/light showers mainly along and north of US-10.

Showers and a few thunderstorms will likely continue percolating
through the southern half of Lower Michigan this afternoon limited
in intensity by weak lapse rates and deep-layer shear. As the
aforementioned MCV tracks along the IN/MI border this evening, an
uptick in coverage of showers and a few thunderstorms is possible
south of I-96 potentially lasting after dark. The track of the MCV
would place southern Lower Michigan in a preferred zone for
persistent forcing but there are questions as to how much
instability will be left after the activity this afternoon.
Regardless, concern remains for a locally heavy rainfall/ponding
on roadways/low-lying areas across the southern two rows of
Michigan through early Sunday given PWATS > 1.5" and a residual
low-level frontal zone. It's worth noting both the 00Z and 12Z SPC
HREF indicate the potential for localized rainfall totals >2"
along I-94 by midnight tonight. An uptick in showers may also
occur after midnight tonight along a secondary cold front (coming
off of Lake Huron), but current indications are coverage should be
spotty.

By Sunday morning, the brunt of the low-level moisture should be
south of the state line but a brief afternoon shower will remain
possible inland from the lake.  Otherwise, the forecast through
Tuesday continues to look quiet (and frankly more comfortable) as a
high pressure system slides through the Great Lakes yielding highs
in the lower 80s, lows in the mid-60s, and light winds.

A fast-moving shortwave trough will swing through the Great Lakes
around the Wednesday timeframe with an associated band of showers
and thunderstorms. While forecast shear may promote modest storm
organization (e.g. 0-6 km and 0-1 km shear on the order of 30 kts
and 20 kts, respectively), meager lapse rates and "tall and
skinny" CAPE profiles will likely limit the intensity of any
thunderstorm. Given PWATS are expected to climb above 1.5" again,
locally heavy downpours will be possible but the progressive
nature to the system will likely mitigate any impacts. Pleasant
weather is then expected to return for the end of the week as
another high pressure system slides through the area.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 1238 PM EDT Sat Jul 6 2019

AZO/BTL/JXN:

Showers and a few thunderstorms are expected to fester along a
boundary draped over the TAF sites this afternoon with an uptick in
coverage expected through roughly 00Z. Winds are also likely to be
variable through 00Z, as well. Have maintained inherited VCTS from
the previous TAF package and will offer amendments as individual
thunderstorms evolve and potentially threaten individual sites. A
cumulus field is expected to transition to a broken cloud deck at or
around 6000 ft this evening as precipitation wanes, before showers
redevelop after midnight tonight (e.g. added VCSH for now).
Northeasterly winds are expected to prevail after sunset tonight
with a trend toward VFR after sunrise Sunday.

MKG:

Broken cloud cover at 6000 ft is expected to this afternoon with
northwesterly winds off Lake Michigan likely holding off
precipitation chances this afternoon. The broken cloud deck will
likely prevail through the evening and overnight hours as
northwesterly winds become reestablished, before gradual improvement
toward sunrise Sunday.

LAN/GRR:

Broken cloud cover at 6000 ft is expected to spread over the TAF
sites this afternoon with "hit or miss" scattered showers. A
thunderstorm is also possible but the possibility appears too low
to mention at this time. The broken cloud cover is expected to
prevail through the overnight hours with improvement after sunrise
Sunday. Note that showers may redevelop after midnight but
confidence is not high enough to include in the TAFs at this time.
Northwesterly winds are expected to prevail through the entirety
of the TAF package.

&&

.MARINE...
Issued at 329 PM EDT Sat Jul 6 2019

Buoy observations and webcams confirm that 2-4 foot waves continue
along the lakeshore owing to northerly flow. While this regime is
more on the marginal side than a slam dunk, we've opted to issue a
Small Craft Advisory and Beach Hazards Statement from Grand Haven
southward for the remainder of the afternoon given a longer duration
of the potential hazardous conditions and high beach/near shore
traffic. Northerly flow will transition to northeasterly tonight
with conditions becoming calmer Sunday. As a high pressure system
swings through the Great Lakes for the early portion of the
workweek, quiet conditions are expected over Lake Michigan.
Waves of 2-4 feet will then be possible on Wednesday as a cold
front swings through the Great Lake. A return to calm conditions
is then expected thereafter.

&&

.GRR WATCHES/WARNINGS/ADVISORIES...
MI...Beach Hazards Statement until 2 AM EDT Sunday for MIZ056-064-071.

LM...Small Craft Advisory until 2 AM EDT Sunday for LMZ844>846.

&&

SYNOPSIS...Borchardt
DISCUSSION...Borchardt
AVIATION...Borchardt
MARINE...Borchardt

Hazardous Weather Outlook
National Weather Service Grand Rapids MI
329 PM EDT Sat Jul 6 2019

MIZ037>040-043>046-050>052-056>059-064>067-071>074-071930-
Mason-Lake-Osceola-Clare-Oceana-Newaygo-Mecosta-Isabella-Muskegon-
Montcalm-Gratiot-Ottawa-Kent-Ionia-Clinton-Allegan-Barry-Eaton-
Ingham-Van Buren-Kalamazoo-Calhoun-Jackson-
329 PM EDT Sat Jul 6 2019

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

.DAY ONE...This Afternoon and Tonight

Scattered thunderstorms with heavy downpours and cloud to ground
lightning are possible mainly south of I-96 through the remainder
of the day. Localized ponding on roadways and low-lying areas is
possible.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Showers and thunderstorms are possible Wednesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

LMZ844>849-071930-
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-
329 PM EDT Sat Jul 6 2019

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

.DAY ONE...This Afternoon and Tonight

An isolated thunderstorm is possible this evening along the
lakeshore.

Conditions will be hazardous to small crafts and beachgoers
south of Grand Haven through 2 AM tonight.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Showers and thunderstorms are possible on Wednesday.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed.

BORCHARDT

Special Weather Statement
National Weather Service Grand Rapids MI
147 PM EDT Sat Jul 6 2019

MIZ071>073-061930-
Van Buren-Kalamazoo-Calhoun-
Including the cities of South Haven, Kalamazoo, and Battle Creek
147 PM EDT Sat Jul 6 2019

...Scattered Storms This Afternoon...

At 145 PM EDT, scattered showers and storms have developed around Paw
Paw, Kalamazoo, Battle Creek, and Marshall. These showers and storms
are drifting slowly toward the southeast. Localized downpours and
wind gusts to 30 mph are possible. Occasional lightning strikes and
water ponding on roadways are also possible. Be alert for changing
weather conditions this afternoon, and be prepared to move indoors
when storms threaten.

CAS