Marine Forecasts

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7 Day Forecast for Marine Location Near Fennville, MI

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Area Discussion for - Grand Rapids, MI

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FXUS63 KGRR 270849 AFDGRR

Area Forecast Discussion National Weather Service Grand Rapids MI 349 AM EST Sat Feb 27 2021

LATEST UPDATE . Synopsis/Discussion/Marine/Hydro

SYNOPSIS. Issued at 348 AM EST Sat Feb 27 2021

- Light wintry mix this morning, becoming partly cloudy for afternoon

- Drizzle late tonight and Sunday AM, small risk for freezing drizzle

- Mild for part of Sunday, then turning windy and cooler

- Cold air arrives Monday, potential for briefly hazardous travel

DISCUSSION. (Today through next Friday) Issued at 348 AM EST Sat Feb 27 2021

- Light wintry mix this morning, becoming partly cloudy for afternoon

Light wintry mix is expected to last until about 7 AM this morning, and could make roads a little slick roughly north of a Douglas to Hastings to St Johns line. South of there, we expect to see mostly rain. Snow accumulations should be fairly light and temperatures should warm above freezing by 10 AM.

After a period of low clouds and lingering haze from mid to late morning, skies should become partly cloudy in the afternoon as surface ridging builds in. Temperatures will rebound nicely from our bout of winter weather this morning, warming to the mid and upper 40s.

- Drizzle late tonight and Sunday AM, small risk for freezing drizzle

Larger chunk of energy embedded within the longwave trough that covers the western CONUS and Midwest will lift through the Western and Central Great Lakes late tonight and Sunday. Warmer air will begin to surge up into the area ahead of this system, but will initially occur above the ground as a southerly low-level jet noses in. Forecast soundings become saturated in the low-levels between 4- 7AM, and favor low clouds and areas of drizzle through mid to late morning. Better potential for drizzle looks to be after surface temperatures rise above freezing, but cannot rule out a brief period of freezing drizzle before this occurs. Main area of concern is interior portions of Central Michigan, which will have more time to temperatures to cool overnight before temperatures begin to rise. Threat for freezing drizzle should end by 10 AM.

- Mild for part of Sunday, then turning windy and cooler

Deepening low pressure will lift across Northern Michigan Sunday, dragging a cold front through the area. Before this occurs, temperatures are expected to warm into the 40s for most of the area, and we may even push 50 degrees towards the I-94 corridor and Lansing. Temperatures will then start to fall (from west to east) during the late afternoon and evening behind the frontal passage, with wind chills by early evening only in the mid 20s to low 30s. Winds will also increase in the mid to late afternoon with the frontal passage. While not all model runs have supported this, the 00Z GFS and Nam do show potential to bring 40-45 mph gusts to the surface.

- Cold air arrives Monday, potential for briefly hazardous travel

Upper low diving into Ontario Monday will drop a strong cold front through the area during the afternoon. Forecast highs in the upper 20s to mid 30s will be reached during the first part of the day. It will feel pretty raw behind the frontal passage by late afternoon as wind chills fall to the single digits and teens. Models have been bouncing around a little with respect to wind speeds for Monday. We will have the support of cold air advection, and the surface gradient will be pretty tight for a brief period. Core of 40-50 knot winds is up around 4-5 kft however, much higher than Sunday, and not as confident we will be able to mix well enough into it. Still see some potential for 40-45 mph gusts, so will not change messaging at this point.

Snow showers will accompany the frontal passage, and they could become briefly intense in the afternoon as low-level lapse rates steepen to between 9-10 C/km. With temperatures dropping and the DGZ saturated, low visibility could be a big issue despite not seeing much snow accumulation, especially when the snow is combined with gusty winds. This is something we are going to have to keep a very close eye on for Monday afternoon as it could cause a sudden and significant change to travel conditions. Will see some lake effect snow showers in the cold air on the backside of the front, but they should become light by evening as high pressure to our west starts to expand over the lake.

AVIATION. (For the 06Z TAFS through 06Z Saturday night) Issued at 1241 AM EST Sat Feb 27 2021

An area of light rain, snow, and a little freezing rain will move through the terminals before tapering off between 10-12Z this morning. Highest confidence in precipitation turning to all rain is along the I-94 corridor. MKG and GRR may initially start as a mix, but latest model guidance and look of upstream radar returns suggest a changeover to all snow showers for a few hours. There may also be some freezing rain at onset of precipitation for all sites, but it should be light, brief, and not have much impact with temperatures right around freezing. Ceilings/visibility are expected to be IFR to MVFR as precipitation works through the area, with IFR favored afterward, roughly between 10-12Z through 14-16Z. Ceilings will then gradually lift and break through the late afternoon.

MARINE. Issued at 348 AM EST Sat Feb 27 2021

Windy conditions are expected to develop both Sunday and Monday as cold fronts work through the area. Small Craft Advisories will likely be needed, and but also watching potential for winds to reach Gale Force each of these days.

HYDROLOGY. Issued at 325 PM EST Thu Feb 25 2021

Nearly half of the snowpack in the Grand and Kalamazoo River basins has melted in the last several days, and the vast majority of the remaining snow will melt by the end of this coming weekend. Ice remains in place - especially on the Grand River - and is steadily weakening and melting in place. General flooding on the Grand and Kalamazoo River is NOT expected as a result of this melting snow. There is a small chance that some localized ice jams could form if and when the ice breaks up and begins to move. A return to colder overnight temperatures for early next week will slow down the movement of water toward the rivers, which this time of year is a good thing. All living near or recreating near the rivers of West Michigan should pay extra attention over the next week or two as we transition into springtime conditions, as conditions can sometimes change quickly.

GRR WATCHES/WARNINGS/ADVISORIES. MI . None. LM . None.

SYNOPSIS . HLO DISCUSSION . HLO AVIATION . HLO HYDROLOGY . AMD MARINE . HLO

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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	11 mi	58 min	S 8.9 G 9.9	32°F	34°F		1010.1 hPa	32°F
SVNM4 - South Haven, MI	20 mi	48 min	11 G 12	34°F
MKGM4 - Muskegon, MI	42 mi	38 min	W 12 G 12	33°F			1012.2 hPa	33°F
SJOM4 - St. Joseph, MI	44 mi	88 min	S 8 G 12	35°F			1011.9 hPa (+1.4)

Wind History for Holland, MI

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NW20 G25

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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	7 mi	35 min	WSW 8	4.00 mi	Fog/Mist	34°F	31°F	89%	1011.6 hPa
South Haven, South Haven Area Regional Airport, MI	22 mi	33 min	WSW 8	5.00 mi	Fog/Mist	36°F	34°F	94%	1011.2 hPa

Link to 5 minute data for KBIV

Wind History from BIV (wind in knots)

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1 day ago

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SW16 G27

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W11 G21

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NW14 G28

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NW10 G25

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Calm

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Calm

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