Marine Weather and Tide Forecast for Garden, MI

SHORT TERM /THROUGH TONIGHT/
Issued at 415 PM EDT Thu Oct 10 2024

Low-amplitude ridging will continue to slide over the Great Lakes tonight, providing subsidence that will build surface high pressure currently centered over the lower peninsula further south tonight, eventually stretching from the southern Great Lakes down to the Gulf Coast. Further upstream, a shortwave embedded in the main mid/upper- level flow will punch across the Rockies and over the northern Great Plains by the end of the period.

Dry weather is expected across the area through the remainder of the evening into Friday morning. South to southwest winds around 10 mph with gusts to 20-30 mph at times are anticipated this evening and tonight as high pressure continues to build further southeast of the U.P., leading to a tighter pressure gradient across the area. While confidence is relatively low at this time, occasional wind gusts in excess of 30 mph cannot be completely ruled out with strong winds of 40-50 mph just above the surface. Otherwise, these winds will help keep mild temperatures in place overnight with lows ranging from the mid/upper 50s across the western U.P. to the mid/upper 40s across the central U.P. A cold front associated with an elongated surface cyclone traversing Hudson Bay will encroach on the far western U.P./Lake Superior by Friday morning.

LONG TERM /FRIDAY THROUGH THURSDAY/
Issued at 415 PM EDT Thu Oct 10 2024

Shortwave troughing will punch over the northern Great Lakes on Friday, eventually working east of the region Friday night into Saturday. As mentioned in the short term discussion, an attendant cold front will also swing across the U.P. Friday morning/afternoon, working into the southern half of the lower peninsula by Friday evening. High pressure is expected to temporarily build in Saturday before strong longwave troughing digs across the Great Lakes late this weekend through early next week. Ample forcing aloft will support the development of a cyclone over the region Saturday night into Sunday, which looks to pivot across New England Monday.
Amplified ridging further upstream will work to build surface high pressure across the much of the Great Plains and Midwest through the first half of next week.

Chances for isolated/scattered showers will return to parts of the central/eastern U.P. on Friday as the aforementioned front moves through. Cannot completely rule out an isolated shower across the western U.P., but low enough confidence currently exists to keep much of this area at less than 20% PoP at this time. Best chances appear to come east of a line from Munising to Gladstone. Any showers are anticipated to be light with little accumulation -- likely around a few hundredths or less given a dry low-level airmass in place making it difficult for rain to reach the surface and more favorable forcing aloft being displaced north of the U.P.

After highs in the mid 60s to low 70s on Friday, much cooler temperatures will be ushered in behind the front through the weekend into early next week. The main focus will be the return of better rain chances Saturday night lasting into Tuesday. With background cyclonic flow through a deep layer for several days, conditions will be favorable for lake enhanced/lake effect showers on the backside of the departing system. As was well discussed by the previous forecaster, strong over-lake instability combined with deep cloud layers will support chances for waterspouts over Lake Superior and graupel showers with any lake-induced convection. Temperatures dipping into the low/mid 30s across some higher terrain areas may result in a mix/transition to snowflakes for a brief time Sunday morning and Monday morning as well.

AVIATION /06Z TAFS THROUGH 06Z SATURDAY/
Issued at 127 AM EDT Fri Oct 11 2024

With a dry air mass largely prevailing despite a passing cold front today, expect VFR to be the rule at IWD/CMX/SAW thru this fcst period. However, there continue to be some indications for a brief period of increased low-level moisture/stratocu for a time in the cold air advection immediately after fropa. For now, only included a mention of sct clouds at 2500-3000ft at all terminals since there is currently no evidence of MVFR cigs behind front. Low-level jet ahead of front and nocturnal inversion will continue to support LLWS at all terminals overnight. This will transition to gusty w to nw sfc winds at 20-30kt today.



MARINE
Issued at 415 PM EDT Thu Oct 10 2024

Southwest winds are expected to increase overnight, becoming 10-20 kts with gusts of 20-30 kts over much of the open waters of Lake Superior as well as the nearshores. A cold front will swing across the region Friday morning into the afternoon, turning winds to northwesterly behind the boundary for most waters by Friday late afternoon. Winds will become increasingly gusty behind the front, including gale force wind gusts at times over most nearshore waters surrounding the Keweenaw Peninsula east to Whitefish point and open waters of Lake Superior east of Isle Royale. Thus, the previous Gale Watch has been upgraded to a Gale Warning. Looking ahead, another round of potential gale force wind gusts may return to portions of Lake Superior late this weekend into early next week. Cold air over the relatively warm waters during that time period combined with deep cloud layers will bring the potential for waterspouts. As this is still a few days away, explicit mention of waterspout potential has not be included in the gridded forecast at this time.

MQT WATCHES/WARNINGS/ADVISORIES
Upper Michigan...
None.
Lake Superior...
Gale Warning from noon today to 10 PM EDT this evening for LSZ243>251-264>267.

Lake Michigan...
None.