Marine Forecasts

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7 Day Forecast for Marine Location Near Pinconning, MI

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Area Discussion for - Detroit/Pontiac, MI

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FXUS63 KDTX 231744 AFDDTX

Area Forecast Discussion National Weather Service Detroit/Pontiac MI 1244 PM EST Sat Jan 23 2021

AVIATION.

High pressure continues to move across the northern Ohio Valley early this afternoon, with northern extent reaching into the airspace and allowing for mainly clear skies with the exception of lingering stratocu at KMBS and KFNT, which has occasionally dipped MVFR at times. Sky attempts to stay mainly clear into the early evening hours before mid/high clouds fill in from the southwest ahead of approaching upper wave that will bring a round of periodic light snow late in the TAF period Sunday after 12z. West/northwest winds 5-10 knots will trend variable overnight for a time before reorienting out of the southeast Sunday.

For DTW . Light snow looks to hold off until after 12z Sunday as southern wing of moisture ascent will take some time to overcome near-surface dry air. Potential will exist for some intervals of MVFR snow towards the end of the period, but confidence not there to include mention at this time.

DTW THRESHOLD PROBABILITIES .

* Low in ceilings below 5000 feet after 12z Sunday.

* High in ptype as snow after 12z Sunday

PREV DISCUSSION. Issued at 358 AM EST Sat Jan 23 2021

DISCUSSION .

Overnight stratus has held on nicely through the early parts of the morning, with rapid erosion of cloud cover now noted via infrared across the Grand Rapids region as mid-level subsidence ahead of surface high pressure currently located over the Midwest. Expecting the continued erosion of stratus to take place (south of the thumb) as high pressure continues to work east into the Ohio Valley by this afternoon. After a very cold start to the morning marked by overnight lows in the teens and wind chills in the single digits, a modest warm up into the mid to upper 20s is expected later today along with some sunshine. As the high pressure tracks east through the evening, low-level flow will back from northwest to southwest. This will usher in low and mid level clouds across the state and will keep overnight lows slightly warmer, holding in the upper teens to lower 20s.

The next chance for light accumulating snowfall will then expand across Michigan throughout Sunday morning (after 6 AM EST) as weak system relative isentropic ascent takes place behind the departing high pressure system. Saturation will initially occur in the mid- levels on the 296-203K surfaces and will have to overcome some initial low level dry air. As the column saturates, expecting light snow to fill on across the state, with slightly better forcing noted across Flint up into the Tri Cities, where likely PoPs hold. Expecting around an inch of accumulation through the early afternoon in and around the Tri Cities, with totals holding under an inch elsewhere (half inch or under for northern Metro region south). Area of best isentropic ascent will then slide into the Thumb during the later part of the afternoon, with snow chances diminishing by the late evening.

Water vapor imagery shows one of the main features of interest for this forecast package, a pv feature just off the coast of California, set to pivot south across Baja California late in the day before ejecting east into TX/OK by early Monday morning. This will result in the development of a low pressure system interacting with a baroclinic zone, set to track north into the Ohio Valley between 00Z Tue - 12Z Tue. Plentiful moisture will eject north across the Ohio Valley and into the Great Lakes ahead of the low pressure system and will bring the likely chance to see accumulating snowfall for portions of SE MI starting late Monday evening into Tuesday morning. Predictability of where the heaviest axis of snowfall (potential for 4+ inches) will fall remains low given it will remain sensitive to both the track of the low and trowal/deformation dynamics. WPC cluster phase space analysis shows the most likely location the axis will fall will be somewhere across southern lower Michigan or south into the northern Ohio Valley. As a result, preliminary forecasted snowfall totals of 3-5 inches will hold over the Metro region down to the Ohio border, with gradually decreasing totals north of this heavier forecasted area. Additional adjustments will be needed as the PV feature comes onshore and is better sampled by the NWS upper-air stations in the coming days.

Last, snow chances are expected to taper off later in the day on Tuesday with high pressure filling in from north to south through the midweek period. This will minimize precipitation chances to end the week while temperature trends remain seasonable.

MARINE .

Northwest winds still gusting up around 25 knots over Lake Huron will gradually diminish today, along with the snow showers. Still, the larger waves over the southern Lake Huron will lag with the unstable near surface profiles. Small craft advisories continue through 11 am for the northern/eastern tip of the Thumb region.

Light and variable winds set up this evening as a ridge of high pressure slides through tonight.

Light southerly flow expected on Sunday as weak low pressure tracks through the northern Great Lakes through Sunday night. A period of light warm advection snow likely in this time frame, but visibility's probably remaining at or above 2 miles.

A much stronger low will lift into the Ohio Valley late Monday, and will lead to increasing east-northeast/onshore flow (up around 25 knots), and small craft advisories may be needed by Monday evening and continued into Tuesday. Snow will likely overspread Lake Erie and Lake St. Clair, and possibly as far north as southern third of lake Huron.

DTX WATCHES/WARNINGS/ADVISORIES. MI . NONE. Lake Huron . NONE. Lake St Clair . NONE. Michigan waters of Lake Erie . NONE.

AVIATION . IRL DISCUSSION . AM MARINE . SC

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

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
SBLM4 - Saginaw Bay Light #1, MI	16 mi	79 min	W 11 G 14	20°F			1026.8 hPa (+1.1)
GSLM4 - Gravelly Shoals Light MI	31 mi	39 min	SW 8.9 G 11	21°F			1027.1 hPa
TAWM4 - Tawas City, MI	46 mi	39 min	WSW 5.1 G 8	23°F			1026.4 hPa

Wind History for Harbor Beach, MI

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NW11 G17

NW10 G16

NW7 G16

NW9 G14

W8 G15

W10 G14

W11 G19

NW11 G14

W10 G14

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NW11 G16

NW12 G17

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NW13 G20

NW9 G17

NW11 G15

NW10 G17

NW12

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NW8 G12

W10 G14

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W7 G11

1 day ago

W11 G19

SW9 G12

SW12 G21

SW8 G15

SW10 G14

W15 G25

W12 G19

W14 G22

W14 G19

W10 G16

W12 G20

W12 G22

W10 G17

NW15 G21

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NW11 G18

NW15 G22

NW15 G24

W14 G22

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2 days ago

W7 G13

SW10 G16

SW11 G14

SW12 G19

S12 G17

S10 G14

S10 G16

S13 G20

S16 G28

S21 G28

S15 G20

SW20 G30

SW17 G21

SW18 G26

SW13 G25

SW13 G18

SW14 G21

SW10 G17

W13 G18

W11 G15

SW15

W15 G20

W12 G21

W9 G16

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Jack Barstow Airport, MI	15 mi	24 min	WSW 7	10.00 mi	Mostly Cloudy	25°F	12°F	58%	1027.4 hPa
MBS International Airport, MI	16 mi	26 min	WSW 7	10.00 mi	Fair	24°F	11°F	57%	1028.8 hPa
Saginaw County H W Browne Airport, MI	23 mi	24 min	W 8	10.00 mi	Partly Cloudy	27°F	12°F	54%	1027.8 hPa

Link to 5 minute data for KIKW

Wind History from IKW (wind in knots)

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NW13 G16

NW10 G20

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W9 G16

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1 day ago

W13 G19

SW11 G19

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W14 G24

W12 G19

W16 G21

W11 G16

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SW14 G19

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NW10 G18

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NW9 G16

NW14 G19

W10 G15

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W9 G15

W12 G18

2 days ago

SW11 G16

S12 G16

S9

S13 G21

SW10 G21

S12 G17

S13 G17

S10 G15

S14 G18

SW9 G19

SW12 G19

SW11 G22

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SW10 G17

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W10 G18

W11 G18

W11 G18

W13 G17

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Tide / Current Tables for

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Tide / Current Tables for

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Weather Map

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NOTE: East coast views moved to GEOS-16. They are experimental and not well supported by NOAA so they may not be correct so be warned. This change required redoing a large amount of the GOES code. If the image you are expecting is not showing, please let me know. You may need to use the EDIT function to update your location.
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Ground Weather Radar Station

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