Marine Weather and Tide Forecast for Copper City, MI

DISCUSSION
Issued at 355 PM EDT Mon Mar 16 2026

Afternoon GOES water vapor imagery place the mid level trough over the Upper Great Lakes. At the surface, a low pressure is analyzed over Quebec around 987 mb with a similar magnitude trough extending back over northern Lake Huron. As the mid level trough continues east and the embedded shortwave pivots northeast to Quebec, the surface low keeps its northeast departure from the region and the trough over Lake Huron dissipates. As f-gen over the east weakens and high pressure moves in from the west, a transition to LES over the north becoming northwest wind snowbelts will occur. Radar trends have already seen this process at play as the heavy band structures shifted east through early this afternoon and broader reflectivities have thinned out over the west and south-central. Areas underneath upslope flow still are observing rates of up to 1 inch per hour at times which will continue into this evening. Winds this afternoon have been strong, particularly in the eastern two thirds where 30-50 mph gusts have been frequently observed; higher gusts up to 60 mph near central and eastern Lake Superior. As a result, dangerous blizzard conditions persist in those areas. These winds and low visibilities from falling and blowing snow persist into this evening before tapering off from southwest to northeast tonight. Based on web cameras and surface observation visibility trends, opted to cancel the Blizzard Warning in the Keweenaw, then hoisted a Wind Advisory for Keweenaw County through 2 AM EDT...patchy blowing snow is possible to reduce visibility, but persistent 1/4 mile or less are no longer expected. Also adjusted the end times for Iron, Delta, and southern Schoolcraft earlier to better reflect the latest visibility and wind forecasts. Lakeshore Flood Warnings have been downgraded to Advisories for most outside of Marquette/Alger with the winds and wave forecast trending lower.

Winds have likely been a limiting factor for SLRs much of the event, but have improved to 14:1 as of the 18Z observation at the WFO. This is still lower than the NBM has been putting out. Given the near surface DGZ and pockets of dry air noted at times within this region, lowered forecast SLRs to ~13-15:1 for the remainder of the event. This still yields amounts up to 8 inches in the north-central and a foot in the east, focused in on Alger, northern Schoolcraft, northern Delta, and Luce counties through Tuesday morning. Lesser amounts of 1 to 2 inches or less is expected elsewhere within the CWA Otherwise, temps in the teens fall into the single digits tonight. Wind chills tonight will be in the negative single digits to negative teens.

High pressure moving to the south extends ridging overhead on Tuesday, shifting winds west then southwest and ushering in warmer/drier air. LES ends in the west by the afternoon and by the evening in the east. Additional accumulations will struggle to reach 1 inch. Highs will be colder than normal in the mid teens to mid 20s. Mid level ridging over the western CONUS sets the region up for a period of northwest flow, yielding a parade of weak waves keeping PoPs in the forecast. The first one Tuesday night into Wednesday has the support of WAA and Isentropic ascent, but will struggle to yield much of any snow outside the east where Lake Michigan provides some enhancement. This quickly is followed by more precip chances Wednesday night. Friday brings the third wave, but no real accumulations are anticipated until the weekend when a much deeper trough moves through. Model spread leaves many of the details with the weekend system blurry, however chances for both rain and snow increase this week as a warmer airmass returns. Highs late week return to the 30s and 40s, warmest interior west.

AVIATION /18Z TAFS THROUGH 18Z TUESDAY/
Issued at 242 PM EDT Mon Mar 16 2026

A strong winter storm continues to affect the area this afternoon.
KSAW will remain below airport minimums into this evening.
Conditions this evening will remain IFR at CMX while IWD will see MVFR conditions. Overnight, winds will die down and conditions will improve. By 12Z on Tuesday, KSAW will be up to IFR conditions.

MARINE
Issued at 411 PM EDT Mon Mar 16 2026

Northerly gales and storms, strongest east, persist into tonight before tapering off from west to east. Storms over the east half end by 2 AM EDT with the lake free of gales by mid Tuesday morning. Cold air filtering over the lake continues the threat of Freezing spray through Tuesday afternoon. Northwest winds fall below 20 kts lakewide by Tuesday evening as high pressure passes overhead, backing southwest into Tuesday night.

A low pressure tracking over northern Ontario on Wednesday increases southwest winds up to 15-30 kts late Tuesday night through much of Wednesday. The remainder of the work week favors weaker systems with limited wind response. The next chance for lakewide winds into the 20-30 kt range is over the weekend, but details are murky at this point.

MQT WATCHES/WARNINGS/ADVISORIES
Upper Michigan...
Lakeshore Flood Advisory until 2 AM EDT Tuesday for MIZ001-007.

Wind Advisory until 2 AM EDT Tuesday for MIZ001.

Lakeshore Flood Advisory until 5 PM EDT this afternoon for MIZ002.

Lakeshore Flood Advisory until 8 PM EDT this evening for MIZ003.

Blizzard Warning until 2 AM EDT Tuesday for MIZ004-005-013-014.

Lakeshore Flood Warning until 2 AM EDT Tuesday for MIZ005.

Blizzard Warning until 8 AM EDT Tuesday for MIZ006-007-085.

Lakeshore Flood Warning until 8 AM EDT Tuesday for MIZ006.

Blizzard Warning until 4 PM CDT this afternoon for MIZ010.

Blizzard Warning until 7 PM CDT this evening for MIZ011-012.

Lake Superior...
Gale Warning until 2 AM EDT /1 AM CDT/ Tuesday for LSZ240>242- 263.

Heavy Freezing Spray Warning until 2 AM EDT /1 AM CDT/ Tuesday for LSZ162.

Gale Warning until 8 PM EDT /7 PM CDT/ this evening for LSZ162.

Heavy Freezing Spray Warning until 2 PM EDT /1 PM CDT/ Tuesday for LSZ240>248-263>265.

Storm Warning until 2 AM EDT Tuesday for LSZ243>251-264>267.

Gale Warning from 2 AM to 8 AM EDT Tuesday for LSZ243>251- 264>267.

Heavy Freezing Spray Warning until 5 PM EDT Tuesday for LSZ249>251-266-267.

Lake Michigan...
Gale Warning until 2 AM EDT Tuesday for LMZ248-250.

Heavy Freezing Spray Warning until 2 AM EDT Tuesday for LMZ248- 250.