Marine Forecasts

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7 Day Forecast for Marine Location Near Holland, MI

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Area Discussion for - Grand Rapids, MI

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FXUS63 KGRR 220455 AFDGRR

Area Forecast Discussion National Weather Service Grand Rapids MI 1155 PM EST Thu Jan 21 2021

LATEST UPDATE . Aviation

SYNOPSIS. Issued at 320 PM EST Thu Jan 21 2021

- Lake effect snow showers and colder Friday

- Quiet most of Saturday but chilly

- Light snow Saturday night into Sunday

- Possible snow storm Monday and Thursday

UPDATE. Issued at 1023 PM EST Thu Jan 21 2021

Lake effect snow is ongoing across the area at 1015pm with the stronger activity occurring off to the north of I-96 across Central Lower Michigan. The deeper moisture and better vertical motion exist across Central and Northern Lower Michigan which is closer to the shortwave diving southeastward in the northwest flow aloft. The better moisture and lift will stay in those areas and be confined to the first half of the night or roughly through about 400am. So, we expect the "heavier" snow to remain up in Central Lower Michigan tonight. Also, we expect the intensity of the snow to drop off considerably as we approach daybreak. Snowfall totals will range from an inch or two up along U.S. 10 in a few spots to trace amounts for much of the rest of the forecast area.

A cold front stretches from near Alpena to Ludington to just north of Milwaukee at 1000pm with a solid push to the south ongoing. This front will bring a burst of snow showers to many areas, but they will be short lived at any one location and not result in much in the way of impact. The front will flip the flow from a westerly to more northerly direction. So, overnight once the frontal snow showers pass through the activity will focus more towards the lakeshore.

All in all, a fairly typical January night. Temperatures will tumble behind the front as readings currently are near zero F across northern Minnesota and in the single digits as close as northern Wisconsin. We will see temperatures fall into the teens and lower 20s by daybreak here.

DISCUSSION. (This evening through next Thursday) Issued at 320 PM EST Thu Jan 21 2021

- Lake effect snow showers and colder Friday

Yet another minor lake effect snow event is expected later tonight into Friday night. This event does look a little better now than it did a few days ago but it still will struggle to result in more than a 1/2 inch in most locations by Saturday evening. An isolated 2 inch amount is possible through. We do have cyclonic flow at low levels into Friday and inversion heights will be near 5000ft we do get a snow event from this. A pathetic one, at best, but snow is snow. I do want to point out the NAM has inversion heights only to 4000 ft but the HRRR and RAP model get to 6000 ft. All things considered I would go with the HRRR and RAP on that idea. One way of the other that is not all that deep but there is lift in the DGZ and speed convergence near the lake shore so we will get some light snow showers tonight into Friday night. Winds of 25 to 35 knots in the clouds will bring the snow bands well inland into Friday. That deceases snowfall too through, since it spreads the snowfall out over a larger area.

Thanks to large upper high moving westward over Greenland we get a brief window to get some truly cold air into Southwest Michigan during the next in the next 24hrs. The problem with this cold air is that cold air not staying over Michigan for very long. That upper high keeps moving west. That upper high would need to stay over Greenland for us to stay in the cold air. Since it does not stay there, that in turn off the cold air nearly nearly as quickly as it allows it to impact us. None the less, this will be the coldest air of the winter but like every other event this winter,so far, it does not last more then 18-24 hrs. With 850 temperatures falling to near -18c (coldest so far, this winter, for this area) that is more than cold enough given Lake Michigan's mean surface water temperature is near 40 degrees.

- Quiet most of Saturday but chilly

As the next upstream northern and southern stream shortwaves move into North America, that causes a shortwave ridge to move over this area Saturday. That ends the snow shower but it will remain cold.

- Light snow Saturday night into Sunday

As those next upstream shortwave move toward the central CONUS, we get a warm advection snow event. This is in the late Saturday night into midday Sunday time frame. There is a northern stream wave associated with this system so the great snowfall will be over northern Lower Michigan.

- Possible snow storm Monday and Thursday

The southern stream tries to get active again this coming week. Since the ECMWF (as typical) is slower moving upper waves out of the Southwestern CONUS, it allows a better and strong system to head this way than does the GFS which is likely to quick in moving this system east. The ECMWF has had this storm impacting us for at least 6 model runs in a row. Meanwhile the GFS is had it not impacting us for those same model runs. Nearly all of the ECMWF 50 ensemble members like the snow getting into Michigan while only 5 out of the 30 GFS members like that idea. If it happens it would be the largest snow storm of the season so far (which given what has happens so far is not saying much).

If you like that event, then we have a similar event on Thursday to watch. It is very similar to the Monday event. So that will be the next system to watch for.

AVIATION. (For the 06Z TAFS through 06Z Friday night) Issued at 1155 PM EST Thu Jan 21 2021

Widespread MVFR ceilings should spread across the TAF sites in the next couple of hours, or through 08z. The MVFR ceilings should remain in place the rest of the night and through much of Thursday. Scattered snow showers can be expected the remainder of the night, but overall heavy snow shower activity is not expected at the TAF sites. Periodic dips in visibility are possible, to 3-5SM, but overall VFR visibilities are expected. The snow shower activity is expected to be even lighter on Friday, generally flurries.

Winds will remain gusty tonight into the 20-30 knot range out of the northwest, but a gradual settling of the wind will occur between now and Friday evening.

MARINE. Issued at 320 PM EST Thu Jan 21 2021

With the cold air coming in, little question we will have 20 to 30 knot winds over the near shore into Friday night. So no changes needed in the marine headlines.

GRR WATCHES/WARNINGS/ADVISORIES. MI . None. LM . Small Craft Advisory until 3 AM EST Saturday for LMZ844>849.



UPDATE . Duke SYNOPSIS . wdm DISCUSSION . wdm AVIATION . Duke MARINE . wdm

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Weather Reporting Stations

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Stations	Dist	Age	Wind	Air Temp	Water Temp	Waves	Pressure	DewPt
HLNM4 - 9087031 - Holland, MI	6 mi	67 min	WNW 23 G 27	36°F	34°F		1006.2 hPa	26°F
SVNM4 - South Haven, MI	27 mi	55 min	25 G 28	36°F
MKGM4 - Muskegon, MI	34 mi	55 min	N 22 G 29	31°F			1008.7 hPa (+2.4)	22°F
SJOM4 - St. Joseph, MI	51 mi	55 min	W 19 G 24	36°F			1008.8 hPa (+0.7)

Wind History for Holland, MI

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SW25 G32

SW23 G28

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W17 G21

W15 G19

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W19 G24

W21 G27

SW23 G28

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NW18 G27

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W26 G32

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1 day ago

N5 G8

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NW21 G26

NW17 G24

NW12 G17

W11 G15

W8 G12

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W19 G23

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W14 G18

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W13 G17

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NW10 G13

N17 G21

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NW20 G25

NE8 G11

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Airport Reports

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Airport	Dist	Age	Wind kt	Visibility	Sky/Weather	Temp	DewPt	Humidity	Pressure
Holland - West Michigan Regional Airport, MI	1 mi	62 min	WNW 12 G 23	10.00 mi	Overcast	36°F	20°F	52%	1007.1 hPa

Link to 5 minute data for KBIV

Wind History from BIV (wind in knots)

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W16 G26

W18 G28

W20 G29

W21 G33

W22 G30

W16 G29

W12 G24

W10 G22

NW12 G21

NW9 G17

W14 G19

W12 G25

W11 G27

W12 G23

1 day ago

N4

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NW11 G18

NW12 G19

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SW13 G23

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2 days ago

W9

W10 G24

W11 G19

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W11 G20

W12 G22

W11 G21

W9 G18

W11 G17

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Tide / Current Tables for

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Weather Map

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Ground Weather Radar Station

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