Small Craft Advisory 63, NWS Detroit, MI

158 
WHUS73 KDTX 241937
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
337 PM EDT Sun Oct 24 2021

LHZ362-363-421-422-441>443-462>464-250830-
/O.UPG.KDTX.GL.A.0011.211025T0800Z-211026T0800Z/
/O.NEW.KDTX.GL.W.0015.211025T0400Z-211026T0800Z/
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond
5NM off shore-
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off
shore-
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
337 PM EDT Sun Oct 24 2021

...GALE WARNING IN EFFECT FROM MIDNIGHT TONIGHT TO 4 AM EDT
TUESDAY...

* WHAT...Expect sustained winds up to 31 knots from the 
  northeast with gusts up to 41 knots. The largest significant 
  waves will be 12 feet with a potential maximum wave height of 
  17 feet.

* WHERE...Portions of Lake Huron. 

* WHEN...The maximum winds are expected around 5 PM EDT Monday 
  with the largest waves expected around 12 AM EDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LEZ444-250830-
/O.EXT.KDTX.SC.Y.0063.211024T2000Z-211025T1400Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
337 PM EDT Sun Oct 24 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 10 AM EDT MONDAY...

* WHAT...Expect sustained winds up to 22 knots from the 
  northeast with gusts up to 25 knots. The largest significant 
  waves will be 4 feet with a potential maximum wave height of 5 
  feet.

* WHERE...Michigan Waters of Lake Erie from Detroit River to 
  North Cape MI.

* WHEN...The maximum winds are expected around 9 PM EDT Sunday 
  with the largest waves expected around 12 AM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LCZ460-250800-
/O.CON.KDTX.SC.Y.0063.211024T2000Z-211025T0800Z/
Lake St Clair-
337 PM EDT Sun Oct 24 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 4 AM EDT MONDAY...

* WHAT...Expect sustained winds up to 18 knots from the 
  northeast with gusts up to 25 knots. The largest significant 
  waves will be 2 feet with a potential maximum wave height of 3 
  feet.

* WHERE...Lake St Clair.

* WHEN...The maximum winds are expected around 12 AM EDT Monday 
  with the largest waves expected around 3 AM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

IRL

757 
WHUS73 KDTX 250812
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
412 AM EDT Mon Oct 25 2021

LCZ460-252015-
/O.EXP.KDTX.SC.Y.0063.000000T0000Z-211025T0800Z/
/O.NEW.KDTX.SC.Y.0064.211025T0812Z-211027T0200Z/
Lake St Clair-
412 AM EDT Mon Oct 25 2021

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 10 PM EDT TUESDAY...

* WHAT...Expect sustained winds up to 25 knots from the north 
  with gusts up to 30 knots. The largest significant waves will 
  be 3 feet with a potential maximum wave height of 4 feet.

* WHERE...Lake St Clair.

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 9 PM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

* ADDITIONAL DETAILS...PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LHZ362-363-421-422-441>443-462>464-252015-
/O.CON.KDTX.GL.W.0015.000000T0000Z-211026T0800Z/
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond
5NM off shore-
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off
shore-
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
412 AM EDT Mon Oct 25 2021

...GALE WARNING REMAINS IN EFFECT UNTIL 4 AM EDT TUESDAY...

* WHAT...Expect sustained winds up to 31 knots from the 
  northeast with gusts up to 42 knots. The largest significant 
  waves will be 13 feet with a potential maximum wave height of 
  19 feet.

* WHERE...Portions of Lake Huron. 

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 1 AM EDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LEZ444-252015-
/O.EXT.KDTX.SC.Y.0063.000000T0000Z-211027T0200Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
412 AM EDT Mon Oct 25 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 10 PM EDT TUESDAY...

* WHAT...Expect sustained winds up to 23 knots from the north 
  with gusts up to 28 knots. The largest significant waves will 
  be 4 feet with a potential maximum wave height of 5 feet.

* WHERE...Michigan Waters of Lake Erie from Detroit River to 
  North Cape MI.

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 4 AM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

790 
WHUS73 KDTX 251934
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
334 PM EDT Mon Oct 25 2021

LHZ362-363-421-422-441>443-462>464-260800-
/O.CON.KDTX.GL.W.0015.000000T0000Z-211026T0800Z/
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond
5NM off shore-
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off
shore-
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
334 PM EDT Mon Oct 25 2021

...GALE WARNING REMAINS IN EFFECT UNTIL 4 AM EDT TUESDAY...

* WHAT...Expect sustained winds up to 30 knots from the 
  northeast with gusts up to 40 knots. The largest significant 
  waves will be 13 feet with a potential maximum wave height of 
  19 feet.

* WHERE...Portions of Lake Huron. 

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 1 AM EDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LCZ460-260930-
/O.CON.KDTX.SC.Y.0064.000000T0000Z-211027T0200Z/
Lake St Clair-
334 PM EDT Mon Oct 25 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT
TUESDAY...

* WHAT...Expect sustained winds up to 24 knots from the north 
  with gusts up to 27 knots. The largest significant waves will 
  be 3 feet with a potential maximum wave height of 4 feet.

* WHERE...Lake St Clair.

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 9 PM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LEZ444-260930-
/O.CON.KDTX.SC.Y.0063.000000T0000Z-211027T0200Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
334 PM EDT Mon Oct 25 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT
TUESDAY...

* WHAT...Expect sustained winds up to 22 knots from the north with
  gusts up to 30 knots. The largest significant waves will be 3
  feet with a potential maximum wave height of 5 feet.

* WHERE...Michigan Waters of Lake Erie from Detroit River to 
  North Cape MI.

* WHEN...The maximum winds are expected around 9 PM EDT Monday 
  with the largest waves expected around 8 PM EDT Monday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

720 
WHUS73 KDTX 260722
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
322 AM EDT Tue Oct 26 2021

LHZ421-422-261930-
/O.CAN.KDTX.GL.W.0015.000000T0000Z-211026T0800Z/
/O.EXB.KDTX.SC.Y.0064.000000T0000Z-211026T2000Z/
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
322 AM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 4 PM EDT THIS AFTERNOON...
...GALE WARNING IS CANCELLED...

* WHAT...Expect sustained winds up to 23 knots from the north 
  with gusts up to 31 knots. The largest significant waves will 
  be 9 feet with a potential maximum wave height of 13 feet.

* WHERE...Outer Saginaw Bay SW of Alabaster to Port Austin MI to 
  Inner Saginaw Bay and Inner Saginaw Bay SW of Point Au Gres to 
  Bay Port MI.

* WHEN...The maximum winds are expected around 3 AM EDT Tuesday 
  with the largest waves expected around 3 AM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LHZ362-260830-
/O.CAN.KDTX.GL.W.0015.000000T0000Z-211026T0800Z/
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond
5NM off shore-
322 AM EDT Tue Oct 26 2021

...GALE WARNING IS CANCELLED...

$$

LHZ363-441>443-462>464-261930-
/O.EXT.KDTX.GL.W.0015.000000T0000Z-211026T2000Z/
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off
shore-Port Austin to Harbor Beach MI-
Harbor Beach to Port Sanilac MI-Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
322 AM EDT Tue Oct 26 2021

...GALE WARNING NOW IN EFFECT UNTIL 4 PM EDT THIS AFTERNOON...

* WHAT...Expect sustained winds up to 26 knots from the north 
  with gusts up to 34 knots. The largest significant waves will 
  be 12 feet with a potential maximum wave height of 17 feet.

* WHERE...Portions of Lake Huron. 

* WHEN...The maximum winds are expected around 3 AM EDT Tuesday 
  with the largest waves expected around 3 AM EDT Tuesday.

* IMPACTS...Strong winds will cause hazardous waves which could 
  capsize or damage vessels and reduce visibility.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Mariners should alter plans to avoid these hazardous conditions.
Remain in port, seek safe harbor, alter course, and/or secure the
vessel for severe conditions.

&&

$$

LCZ460-261930-
/O.CON.KDTX.SC.Y.0064.000000T0000Z-211027T0200Z/
Lake St Clair-
322 AM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

* WHAT...Expect sustained winds up to 19 knots from the north 
  with gusts up to 28 knots. The largest significant waves will 
  be 2 feet with a potential maximum wave height of 3 feet.

* WHERE...Lake St Clair.

* WHEN...The maximum winds are expected around 7 AM EDT Tuesday 
  with the largest waves expected around 3 AM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LEZ444-261930-
/O.CON.KDTX.SC.Y.0063.000000T0000Z-211027T0200Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
322 AM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

* WHAT...Expect sustained winds up to 19 knots from the north 
  with gusts up to 26 knots. The largest significant waves will 
  be 3 feet with a potential maximum wave height of 4 feet.

* WHERE...Michigan Waters of Lake Erie from Detroit River to 
  North Cape MI.

* WHEN...The maximum winds are expected around 3 AM EDT Tuesday 
  with the largest waves expected around 3 AM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

858 
WHUS73 KDTX 261945
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
345 PM EDT Tue Oct 26 2021

LHZ441>443-271200-
/O.CAN.KDTX.GL.W.0015.000000T0000Z-211026T2000Z/
/O.EXB.KDTX.SC.Y.0064.000000T0000Z-211027T1200Z/
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
345 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY IN EFFECT UNTIL 8 AM EDT WEDNESDAY...
...GALE WARNING IS CANCELLED...

* WHAT...Expect sustained winds up to 22 knots from the north 
  with gusts up to 31 knots. The largest significant waves will 
  be 9 feet with a potential maximum wave height of 13 feet.

* WHERE...Port Austin to Harbor Beach MI, Harbor Beach to Port 
  Sanilac MI and Port Sanilac to Port Huron MI.

* WHEN...The maximum winds are expected around 3 PM EDT Tuesday 
  with the largest waves expected around 3 PM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LHZ363-462>464-262045-
/O.CAN.KDTX.GL.W.0015.000000T0000Z-211026T2000Z/
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off
shore-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
345 PM EDT Tue Oct 26 2021

...GALE WARNING IS CANCELLED...

Northerly winds gusting up around 30 knots this afternoon will
continue to slowly diminish this evening. 

$$

LHZ422-262045-
/O.CAN.KDTX.SC.Y.0064.000000T0000Z-211026T2000Z/
Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
345 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY IS CANCELLED...

Northwest winds have dropped below 20 knots and thus the small
craft advisory has been cancelled. 

$$

LHZ421-271200-
/O.EXT.KDTX.SC.Y.0064.000000T0000Z-211027T1200Z/
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-
345 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY NOW IN EFFECT UNTIL 8 AM EDT WEDNESDAY...

* WHAT...Expect sustained winds up to 20 knots from the north 
  with gusts up to 28 knots. The largest significant waves will 
  be 7 feet with a potential maximum wave height of 10 feet.

* WHERE...Outer Saginaw Bay SW of Alabaster to Port Austin MI to 
  Inner Saginaw Bay.

* WHEN...The maximum winds are expected around 3 PM EDT Tuesday 
  with the largest waves expected around 3 PM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LCZ460-270200-
/O.CON.KDTX.SC.Y.0064.000000T0000Z-211027T0200Z/
Lake St Clair-
345 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

* WHAT...Expect sustained winds up to 18 knots from the north 
  with gusts up to 26 knots. The largest significant waves will 
  be 2 feet with a potential maximum wave height of 3 feet.

* WHERE...Lake St Clair.

* WHEN...The maximum winds are expected around 3 PM EDT Tuesday 
  with the largest waves expected around 3 PM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

LEZ444-270200-
/O.CON.KDTX.SC.Y.0063.000000T0000Z-211027T0200Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
345 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 10 PM EDT THIS
EVENING...

* WHAT...Expect sustained winds up to 17 knots from the north 
  with gusts up to 25 knots. The largest significant waves will 
  be 2 feet with a potential maximum wave height of 3 feet.

* WHERE...Michigan Waters of Lake Erie from Detroit River to 
  North Cape MI.

* WHEN...The maximum winds are expected around 4 PM EDT Tuesday 
  with the largest waves expected around 3 PM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

811 
WHUS73 KDTX 270124
MWWDTX

URGENT - MARINE WEATHER MESSAGE
National Weather Service Detroit/Pontiac MI
924 PM EDT Tue Oct 26 2021

LCZ460-270230-
/O.CAN.KDTX.SC.Y.0064.000000T0000Z-211027T0200Z/
Lake St Clair-
924 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY IS CANCELLED...

Northwest winds have decreased to 20 knots or less and will
continue to diminish tonight. 

$$

LEZ444-270230-
/O.CAN.KDTX.SC.Y.0063.000000T0000Z-211027T0200Z/
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
924 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY IS CANCELLED...

Northwest winds have decreased to 20 knots or less and will
continue to diminish tonight. 


$$

LHZ421-441>443-271200-
/O.CON.KDTX.SC.Y.0064.000000T0000Z-211027T1200Z/
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner
Saginaw Bay-Port Austin to Harbor Beach MI-
Harbor Beach to Port Sanilac MI-Port Sanilac to Port Huron MI-
924 PM EDT Tue Oct 26 2021

...SMALL CRAFT ADVISORY REMAINS IN EFFECT UNTIL 8 AM EDT
WEDNESDAY...

* WHAT...Expect sustained winds up to 19 knots from the north 
  with gusts up to 26 knots. The largest significant waves will 
  be 6 feet with a potential maximum wave height of 8 feet.

* WHERE...Port Austin to Harbor Beach MI, Harbor Beach to Port 
  Sanilac MI, Port Sanilac to Port Huron MI and Outer Saginaw 
  Bay SW of Alabaster to Port Austin MI to Inner Saginaw Bay.

* WHEN...The maximum winds are expected around 9 PM EDT Tuesday 
  with the largest waves expected around 9 PM EDT Tuesday.

* IMPACTS...Conditions will be hazardous to small craft.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

Inexperienced mariners, especially those operating smaller
vessels, should avoid navigating in hazardous conditions.

&&

$$

Area Forecast Discussion
National Weather Service Detroit/Pontiac MI
354 AM EDT Sun Oct 24 2021

.DISCUSSION...

A relatively long duration rain event is forecasted for Southeast
Michigan late today and Monday as a strong area of low pressure
tracks from the Central Plains to the western basin of Lake Erie.

A strong potential vorticity anomaly ejecting into the lee of the
Rocky Mountains has resulted in spin cyclogenesis with a 998mb
surface low in far SW KS. Models have been extremely consistent in
forecasting a very dynamic system across the Midwest today/tonight as
the strong upper level dynamics shift eastward. One of the most
notable aspects of the forecast data has been with regards to the
degree/strength of the deep tropospheric frontogenesis that will
occur in the eastern flank of the system. The warm/thetae advection
appears to occur more as a step function with a series of warm
advection surges.

First warm advection surge will occur this afternoon from the
southern cwa down into Ohio as zonal jet axis over Ontario/Quebec
lifts poleward causing erosion of midlevel cold pool/temperatures
and an instantaneous geopotential height rebound. The main impetus
for rainfall to get started over the cwa will be 322-328Ke frontal
surface surging northward into the area. Textbook ageostrophic
response to right entrance region dynamics causing high end dynamics
to roll eastward with time form northern Illinois through Michigan
to upstate New York. This first window of widespread rain is set
from roughly 18-22Z south of I 69. Some question about how sharp the
northern edge of falling precipitation will be. There is some signal
that suggests 925-850mb frontolysis could set a sharp northern edge.
No real concern for any strong to severe weather today with main +50
knot 850mb low level jet axis remaining fairly veered as it passes
to the south of the state. The next increase in fgen/warm front
forcing appears set from approximately 01-09Z tonight. Predominant
forcing shifts down the column as the warm front lifts northward.
Very strong signal for 850-700mb frontogenesis in the models with
what will be extreme veering wind profile with height under true
deformation over the southern 2 or 4 counties of Southeast Michigan.
It is under this forcing (00Z-12Z Monday) that the majority of the
rainfall will fall for Detroit and areas Downriver. Look of QPF with
in-house probability techniques suggests rainfall rates of/reaching
0.25 inch per 3 hour and greater than 1 inch per 12 hours likely.
Based on the very low static stability existing above the steep
frontal slope, rainfall rates may briefly reach/exceed 0.5 inch per
3 hours. A limiting factor to precipitation amounts may in fact be
some dry slotting issues sneaking in south of I94. Given the modest
rates, event duration, and NBM 75th percentile of 1.50inch will be
forgoing any Flood Watch.

With the main warm advection surge well east of the region, models
show some closing of geopotential heights and a occlusion to the low
pressure system. Main forcing transitions to midlevel deformation
forcing across the northern portions of the cwa. Did increase PoPs
across the board for Monday with no significant concern for amounts.
Raw, breezy conditions anticipated Monday for the majority of the
area, did increase winds. Will need to assess model data coming in
but its possible a Wind Advisory will be needed for the shoreline
areas of Lake Huron with strong onshore winds due to a well mixed,
unstable marine environment. Very well could see sustained winds
exceeding 30 mph particularly Monday afternoon and evening. Did go
out now with a Lakeshore Flood Advisory for the Lake Huron
shoreline.

Strong mid to upper level ridging with surface high pressure will
result in quiet weather to Southeast Michigan Tuesday through
Thursday. Highs Tuesday are only expected to top out in the upper
40s to lower 50s with rebounding temps by Wednesday. A complex
evolution to very strong full latitude trough over the western
United States will govern the weather for the end of the week. The
big question mark remains timing and progression of southern United
States closed low extension. Amplitude of preceding upper level
ridge suggests some initial blocking which should keep widespread
rain out of the area until Friday.

&&

.MARINE...

Low pressure system moving out of the central Plains will continue
deepening as it tracks northeastward towards the northern Ohio
Valley today into Monday bringing an extended period of wet and
unsettled weather. Winds will flip northeasterly with the approach
of the low and strengthen in response to the tightening pressure
gradient. A Gale Watch has been issued for the Lake Huron waters.
due to the rapidly increasing northeast flow. Small Craft Advisories
are in effect for the Michigan Waters of Lake Erie and Lake St
Clair. Northeast flow decreases but remains moderate then heading
into the middle of next week as the low departs off to the east.

&&

.HYDROLOGY...

A long duration rainfall event will begin near the MI and OH state
line by midday Sunday and gradually extend northward downstream of a
strengthening low pressure system emerging from the central Rockies.
A steady feed of moisture into the area in advance of this system
will result in PWATs near 1.25" over southern parts of the forecast
area which should translate into 1 to 3 inches of rainfall over the
southern half of the area. Lighter totals an be expected to the
north of I-69 where one half or three quarters of an inch will be
possible. This system will shift east of the area overnight Monday
night with overall flood impacts generally expected to be minor and
confined to poorly drained and low lying areas. Some gradual river
rises will also occur, but bankfull levels are not anticipated.

&&

.PREV DISCUSSION...
Issued at 1142 PM EDT Sat Oct 23 2021

AVIATION...

Weak high pressure overhead has allowed skies to clear for the most
part. Current dewpoint depressions at PTK/FNT/MBS suggest some
degree of fog is possible toward daybreak given the clear skies and
light winds. Mid/high level clouds will then increase across metro
Detroit by daybreak in advance of an approaching frontal system. The
northern edge of the rain shield associated with this system will
overspread metro Detroit Sun afternoon, resulting in steadily
lowering ceiling heights in rain during the latter half of the day
Sunday.

DTW THRESHOLD PROBABILITIES...

* High in ceilings below 5000 feet Sunday afternoon and evening.

* Low in thunderstorms Sunday night.

&&

.DTX WATCHES/WARNINGS/ADVISORIES...
MI...Frost Advisory until 8 AM EDT this morning for MIZ047>049-053>055-
     060>063-068>070-075-076-082-083.

     Coastal Flood Advisory from 4 AM Monday to 8 AM EDT Tuesday for
     MIZ048-049-054-055-063.

Lake Huron...Gale Watch from late tonight through late Monday night for LHZ362-
     363-421-422-441>443-462>464.

Lake St Clair...Small Craft Advisory from 4 PM this afternoon to 4 AM EDT Monday
     for LCZ460.

Michigan waters of Lake Erie...Small Craft Advisory from 4 PM this afternoon to 4 AM EDT Monday
     for LEZ444.

&&

DISCUSSION...CB
MARINE.......IRL
HYDROLOGY....CB
AVIATION.....SC

You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.

Hazardous Weather Outlook
National Weather Service Detroit/Pontiac MI
311 PM EDT Sat Oct 23 2021

MIZ047>049-053>055-060>063-068>070-075-076-082-083-240900-
Midland-Bay-Huron-Saginaw-Tuscola-Sanilac-Shiawassee-Genesee-Lapeer-
St. Clair-Livingston-Oakland-Macomb-Washtenaw-Wayne-Lenawee-Monroe-
311 PM EDT Sat Oct 23 2021

This hazardous weather outlook is for portions of southeast
Michigan.

.DAY ONE...This Afternoon and Tonight

A Frost Advisory is in overnight. Refer to the latest weather message
for additional information.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

A long duration rainfall event is expected Sunday afternoon through
Monday evening. The heaviest rainfall totals of 2 inches or more
will be possible from I-94 southward.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today and tonight.

LCZ460-LEZ444-LHZ361>363-421-422-441>443-462>464-240900-
Lake St Clair-
Michigan Waters of Lake Erie from Detroit River to North Cape MI-
Lake Huron from 5NM east of Mackinac Bridge to Presque Isle Lt
beyond 5 NM off shore-
Lake Huron from Presque Isle Light to Sturgeon Point MI beyond 5NM
off shore-
Lake Huron from Sturgeon Point to Alabaster MI beyond 5NM off shore-
Outer Saginaw Bay SW of Alabaster to Port Austin MI to Inner Saginaw
Bay-Inner Saginaw Bay SW of Point Au Gres to Bay Port MI-
Port Austin to Harbor Beach MI-Harbor Beach to Port Sanilac MI-
Port Sanilac to Port Huron MI-
Lake Huron from Port Austin to Harbor Beach beyond 5NM Off Shore-
Lake Huron from Harbor Beach to Port Sanilac beyond 5NM Off Shore-
Lake Huron from Port Sanilac to Port Huron beyond 5NM Off Shore-
311 PM EDT Sat Oct 23 2021

This hazardous weather outlook is for portions of Lake Erie, Lake
Huron and Lake St Clair.

.DAY ONE...This Afternoon and Tonight

No hazardous weather is expected at this time.

.DAYS TWO THROUGH SEVEN...Sunday through Friday

Small Craft Advisories will likely be needed for much or all of the
nearshore waters from Sunday night into Monday night.

.SPOTTER INFORMATION STATEMENT...

Spotter activation will not be needed today and tonight.

You can obtain your latest National Weather Service forecasts online
at www.weather.gov/detroit.

DG