Small Craft Advisory 68, NWS Gaylord, MI

849 
WHUS73 KAPX 060008
MWWAPX

URGENT - MARINE WEATHER MESSAGE
NATIONAL WEATHER SERVICE GAYLORD MI
808 PM EDT SAT AUG 5 2017

LHZ347-348-060115-
/O.CAN.KAPX.SC.Y.0068.000000T0000Z-170806T0200Z/
5NM EAST OF MACKINAC BRIDGE TO PRESQUE ISLE LIGHT MI INCLUDING
BOIS BLANC ISLAND-
PRESQUE ISLE LIGHT TO STURGEON PT MI INCLUDING THUNDER BAY
NATIONAL MARINE SANCTUARY-
808 PM EDT SAT AUG 5 2017

...SMALL CRAFT ADVISORY IS CANCELLED...

THE NATIONAL WEATHER SERVICE IN GAYLORD HAS CANCELLED THE SMALL
CRAFT ADVISORY. 

GUSTY WINDS HAVE DIMINISHED THIS EVENING. THEREFORE THE SMALL 
CRAFT ADVISORY HAS BEEN CANCELLED.

$$

Area Forecast Discussion
National Weather Service Gaylord MI
336 PM EDT Sat Aug 5 2017

.NEAR TERM...(Tonight through Sunday)
Issued at 337 PM EDT Sat Aug 5 2017

...Remaining coolish, some showers on Sunday...

High impact weather potential...few non-svr thunderstorms northern
lower MI Sunday afternoon.

High pressure in eastern KY is extending ridging into the upper MS
valley. This ridge separates a departing low in Quebec, and an
incoming low in western KS. Diurnal heating, combined with the
coolest temps remaining aloft, have contributed to some showers over
eastern upper and far ne lower MI. Though that will wane, a stray
diurnal shower from upstream could drift into the region. Better
chances for rain will play out on Sunday in northern lower MI, as
low pressure advances toward the lower OH Valley.

As mentioned above, ongoing diurnal showers over far eastern upper
and ne lower MI will dissipate quickly this evening. However,
additional diurnal showers are firing upstream in ne WI and western
upper MI. This activity also won't have an especially long lifetime.
But, with a coolish airmass in place and a warmer Lake MI, these may
have somewhat more success in crossing the lake than one would
otherwise expect. A stray late afternoon thru mid-evening shower may
be needed in parts of nw lower MI. Otherwise, the wx looks largely
quite late tonight into the start of Sunday...though with some
potential for steepish mid-level lapse rates and the return of 850-
700mb warm advection to allow a stray elevated shower in parts of
northern lower.

Better chances for rain arrive Sunday, particularly in the
afternoon. The incoming low is well to our sw and won't provide a
lot of dynamic support for precip, outside of generally weak warm
advection. However, moist advection will be more prevalent,
especially below 700mb. This should not be enough moisture (or lift)
for widespread cloud cover. So diurnal heating should be sufficient
to develop enough instability for lake breezes to trigger
convection. MlCape values of around 500j/kg aren't impressive from a
svr standpoint, and in fact getting thunder at all will be a
somewhat marginal proposition. But there is certainly enough local
forcing/moisture/instability for sct showers, and a rumble/two of
thunder. These will be most prevalent in northern lower MI in the
afternoon, and away from the stabilizing influence of Lake MI.

Min temps on the cool side tonight, upper 40s to mid 50s for most.
Max temps most commonly low/mid 70s.

&&

.SHORT TERM...(Sunday night through Tuesday)
Issued at 337 PM EDT Sat Aug 5 2017

...Mostly Dry and Warming...

High impact weather potential...none.

Surface low tracks up the ohio river valley Sunday night and Monday.
Meanwhile, aloft, upper low moves through Ontario, dragging the main
trough through the region late Monday. Small but sharp ridge moves
through Tuesday.

Surface low is quite far south for significant , but models
showing 70+% RH in the 850-700mb layer Sunday night with some weak
energy moving through northern MI until upper trough goes
through. So small chance for lingering showers Sunday night.
Monday, daytime heating and cold pool overhead could kick off some
isolated afternoon showers south until mid level moisture is
stripped away with the upper trough. Otherwise, high moves in
Monday night, clearing out skies and helping temperatures Tuesday
warm to near normal.

&&

.LONG TERM...(Tuesday night through Saturday)
Issued at 337 PM EDT Sat Aug 5 2017

Extended continues to look fairly quiet into the weekend, with high
pressure overhead most of the time. A weak, elongated boundary could
bring some scattered showers Thursday. Details are a little murky
into the weekend with rain/storm chances. Seeing signs across
guidance for a potential cutoff low to our west. Some are a little
faster with it and could affect the area Saturday, some a bit slower
and affecting the area Sunday. Will see how it develops in the
coming days. Temperatures expected to run near to slightly above
normal through the period.

&&

.AVIATION...(For the 18Z TAFS through 18Z Sunday afternoon)
Issued at 137 PM EDT Sat Aug 5 2017

VFR. Some showers possible late tonight into Sunday.

Low pressure will continue to move away from the region, across
Quebec. However, an incoming low will move east from the
central/southern high plains. Clouds will thicken into lower MI
ahead of this low tonight, and some showers will enter the picture
very late tonight into Sunday. MBL has the best chance of being
impacted by showers, though this will fall out of a mid-cloud
deck, and VFR conditions are expected.

Ongoing gusty nw winds will back to the sw and decrease
substantially late today into tonight.

&&

.MARINE...
Issued at 337 PM EDT Sat Aug 5 2017

Winds/waves will continue to diminish as low pressure moves away
from western Quebec. We'll return to a somewhat more typical late
summer pattern, with weaker systems impacting the region. A ridge
of high pressure will edge east from the Upper MS Valley, before a
low advances east toward the Ohio Valley by Sunday night. A light
westerly breeze Sunday will become northerly on Monday.

&&

.APX WATCHES/WARNINGS/ADVISORIES...
MI...BEACH HAZARDS STATEMENT until 6 PM EDT this evening for MIZ017-
     018-024.
LH...SMALL CRAFT ADVISORY until 6 PM EDT this evening for LHZ345-346-
     349.
     GALE WARNING until 6 PM EDT this evening for LHZ347-348.
LM...NONE.
LS...NONE.
&&

NEAR TERM...JZ
SHORT TERM...KF
LONG TERM...AM
AVIATION...JZ
MARINE...JZ

Hazardous Weather Outlook
National Weather Service Gaylord MI
1203 PM EDT Sat Aug 5 2017

LHZ345>349-LMZ323-341-342-344>346-LSZ321-322-MIZ008-015>036-041-042-
061200-
Straits of Mackinac within 5 nm of Mackinac Bridge including
Mackinac Island-St Ignace to False Detour Channel-5NM East of
Mackinac Bridge to Presque Isle Light MI including Bois Blanc Island-
Presque Isle Light to Sturgeon Pt MI Including Thunder Bay National
Marine Sanctuary-Sturgeon Pt to Alabaster MI-Grand Traverse Bay
south of a line Grand Traverse Light to Norwood MI-Seul Choix Point
to 5NM West of Mackinac Bridge-Norwood MI to 5NM West of Mackinac
Bridge including Little Traverse Bay-Sleeping Bear Point to Grand
Traverse Light MI-Point Betsie to Sleeping Bear Point MI-Manistee to
Point Betsie MI-Whitefish Bay (U.S. Portion)/Whitefish Point to
Point Iroquois MI-St. Marys River Point Iroquois to E.
Potagannissing Bay-Chippewa-Mackinac-Emmet-Cheboygan-Presque Isle-
Charlevoix-Leelanau-Antrim-Otsego-Montmorency-Alpena-Benzie-Grand
Traverse-Kalkaska-Crawford-Oscoda-Alcona-Manistee-Wexford-Missaukee-
Roscommon-Ogemaw-Iosco-Gladwin-Arenac-
1203 PM EDT Sat Aug 5 2017

This hazardous weather outlook is for northern Lower Michigan...
eastern Upper Michigan...and adjacent nearshore waters of Lake
Michigan...Lake Huron and Lake Superior.

.DAY ONE...Today and tonight.

Gale force winds gusts are expected on parts of Lake Huron this
afternoon.

High swim risk conditions due to strong waves and currents will
persist through this afternoon on Lake Huron beaches of northeast
lower Michigan...mainly from Thunder Bay to the Straits.

.DAYS TWO THROUGH SEVEN...Sunday through Friday.

There is a slight chance of thunderstorms on Sunday across
northern Lower Michigan. Severe storms are not expected.

.SPOTTER INFORMATION STATEMENT...

Spotters are encouraged to report any significant weather and
rainfall amounts to the National Weather Service. Reports may be
made one of three ways:

Online:   weather.gov/gaylord
Facebook: facebook.com/nwsgaylord

Twitter:  twitter.com/nwsgaylord

&&

For more information visit http://weather.gov/gaylord.

JZ