Copper Harbor, MI Marine Weather and Tide Forecast

Marine Weather and Tide Forecast for Copper Harbor, MI

December 9, 2023 7:51 AM EST (12:51 UTC)
Sunrise 8:19AM   Sunset 5:04PM   Moonrise  4:44AM   Moonset 2:49PM 

NOTE: Some of the data on this page has not been verified and should be used with that in mind. It may and occasionally will, be wrong. The tide reports are by xtide and are NOT FOR NAVIGATION. Privacy and Cookie policy

Marine Forecasts
    EDIT      Help
LSZ244 / 458 Pm Edt Thu Oct 5 2023
.a special marine warning remains in effect until 515 pm edt...
for the following areas... Eagle river to manitou island mi... Lake superior east of a line from manitou island to marquette mi and west of a line from grand marais mi to the us/canadian border beyond 5nm from shore... Lake superior from upper entrance to portage canal to manitou island mi 5nm off shore to the us/canadian border... Manitou island to point isabelle mi...
at 457 pm edt, a severe Thunderstorm capable of producing waterspouts was located near brockway mountain, or 28 nm northwest of stannard rock, moving northeast at 40 knots.
hazard...waterspouts, wind gusts 34 knots or greater, and small hail.
source...radar indicated.
impact...waterspouts can easily overturn boats and create locally hazardous seas. Small craft could be damaged in briefly higher winds and suddenly higher waves.
locations impacted include... Manitou island.
precautionary/preparedness actions...
move to safe harbor until hazardous weather passes.
Thunderstorms can produce sudden waterspouts. Waterspouts can easily overturn boats and create locally hazardous seas. SEek safe harbor immediately.
lat...lon 4763 8760 4743 8747 4732 8786 4749 8801 4766 8762 time...mot...loc 2057z 241deg 40kt 4745 8781
waterspout...possible hail...<.75in wind...>34kts

No data

7 Day Forecast for Marine Location Near Copper Harbor, MI
   Hourly   EDIT   Help   Map

Area Discussion for - Marquette, MI
      (on/off)   Help   
NOTE: mouseover dotted underlined text for definition

Area Forecast Discussion National Weather Service Marquette MI 657 AM EST Sat Dec 9 2023

(Today and tonight)
Issued at 330 AM EST SAT DEC 9 2023

Key Messages:

- Rain spreads north across Upper MI this morning, except possibly the far west around Ironwood, then mostly lifts out of the area during the afternoon.
- The rain may mix with or change to sloppy, wet snow over portions of the west half of Upper MI, but accumulations will be minimal, under 1 inch.
- Another area of rain and snow will move into western Upper Michigan this afternoon, spreading e through tonight as the precipitation transitions to all snow.
- 1 to 4 inches of wet snow accumulation expected west and north tonight, greatest high terrain of the west.

Water vapor imagery and RAP analysis shows mid-level troffing over the Plains and Rockies early this morning. A well-defined wave was over western MN. Another wave is lifting ne into northern IL, and this will be the main feature of interest for today. The wave over MN will be of interest for tonight. With the southern wave, an expanding area of rain is currently developing/spreading out of eastern IA/northern IL into WI. Closer to home, it's been a quiet, unseasonably warm night for early Dec. Temps across Upper MI are currently in the mid 30s to lwr 40s F, several degrees above normal max temps for this time of year, but a few spots in Delta County have fallen to around 30F. Some fog, locally dense, is noted closer to Lake MI.

Shortwave currently lifting into northern IL will quickly head nne into northern Ontario, to the n of Georgian Bay, by evening. As it does, vigorous forcing/12hr 500mb height falls of around 140m combined with anomalous precipitable water increasing to 200-250pct of normal will support rain spreading nne across the fcst area this morning. Only far western Upper MI around Ironwood may escape being affected by the rain associated with this wave. Although the sfc low will track nne across eastern Upper MI and despite it being Dec, the mild antecedent conditions across the area, including dwpts in the mid 30s F, will make it difficult for rain to switch over to accumulating snow in the western portion of the pcpn shield. In addition, since the wave is not phasing with the MN wave, cooling will not arrive soon enough to ensure a quick change to snow. Fcst will reflect a mix of rain/snow roughly w of an Iron Mtn to Marquette line, but since temps/dwpts won't likely be lwr than the mid 30s F during the pcpn, little if any snow accumulation will occur (under 1 inch), and no travel impacts are expected. Rainfall amounts over most of the e half of the fcst area will be at least one-half inch in general, and possibly up to 0.75 inches or so.

Pcpn associated with the wave will lift out to the ne of the area in the aftn. However, the MN shortwave will shift to WI late aftn/evening, and this will support additional pcpn developing/spreading into Upper MI from the w. A weak sfc trof will also develop wsw from the departing sfc low and ahead of a cold front that will sweep se across the area this evening thru the early overnight period. Both of these features will further aid the second round of pcpn development. 850mb temps over western Lake Superior falling to -4C by evening and to around -8C by midnight will also add an increasing lake enhanced component to the pcpn. Initially as this next area of pcpn develops into western Upper MI, wetbulb zero heights will range upwards to as high as 1400ft agl. So pcpn over the w will begin as mix of rain/snow, more rain than snow closer to Lake Superior and more snow than rain in the high terrain. A transition to all snow will occur from w to e tonight as the pcpn spreads across the entire area. Fcst soundings continue to show bulk of upward motion blo the DGZ, and that combined with temps around freezing during best forcing will hold snow accumulations down. SLRs should be down on the order 10-13 to 1. Overall, expect 1 to 4 inches of snow accumulation tonight across the w and n, greatest in the high terrain of western Upper MI. A few spots may top out around 5 inches from the Porcupine Mtns to Ironwood and also in a small area of the high terrain around Herman in ne Baraga County. Will issue a winter wx advy for Gogebic County given the expectation of exceeding the 3in/12hr snowfall threshold for low SLR snow. Will let dayshift reevaluate whether greater coverage of 3+ inch snow accumulations will occur tonight over western Upper MI, warranting expansion of advy.

(Sunday through Friday)
Issued at 319 AM EST SAT DEC 9 2023

Key messages:

- Light northwest wind lake effect ends west to east through day Sunday.
- Next shortwave/cold front bring gusty west winds especially Lake Superior/Keweenaw late Monday night/Tuesday.
- Other than near normal temperatures Sunday and Tuesday, above normal temperatures will continue through the upcoming week peaking out at 20+ degrees above normal Thursday and Friday.
-No widespread, significant system snowfalls across Upper MI over the next 10 days.

As shortwave exits south and east of the area early Sunday, deeper moisture will quickly depart. 85H temperatures of -10 to -12 will yield some light lake effect but alignment of DGZ and lowering inversion heights will keep accumulations between 1-3 inches mainly east. LES will diminish from west to east through the day.

Ridging overhead on Monday will yield a tranquil December day. Next shortwave will dive southeast into northern Ontario and Upper MI later Monday night. WAA/isentropic ascent ahead of this wave should lead to some light snow developing across the north and east Mon night, followed by west northwest flow lake effect for Tuesday as 850mb temps drop to -16C. Dry air mass moving in behind the front and quick moving nature of the trough will keep lake effect in the 1- 3 inch range...mainly east. Tight pressure gradient will lead to gust west winds across the Keweenaw perhaps up to 40 mph making it feel even chillier...especially given how mild its been so far this early winter.

Ridging returns midweek with a significant warming trend. 85H temperatures anomalies could approach 30 degrees C above normal across western Ontario Thursday into early Friday before next mostly dry front arrives for the weekend cooling things back down. Record highs for late in the week are in the upper 40s to around 50. Not out of the question, especially if there is any sunshine on Thursday.

(For the 12Z TAFS through 12Z Sunday morning)
Issued at 657 AM EST SAT DEC 9 2023

Low pres will quickly lift nne, passing across eastern Upper MI and far eastern Lake Superior this aftn. This low will spread rain across the area, affecting SAW and CMX. Another disturbance will spread rain changing to snow across the area later this aftn thru tonight. At IWD, initial VFR should settle to MVFR by late morning.
-SN will develop late aftn/early evening, dropping conditions to IFR thru the night. At CMX, initial VFR should fall to IFR late morning as -ra develops. The -ra will mix with and change to -sn this evening, dropping conditions to IFR. At SAW, expect VFR to fall to IFR in the next couple of hrs as steady rain moves across the area.
Although -ra will likely end for a while late aftn/early evening, -sn will develop mid to late evening at SAW. IFR will continue. As the -sn diminishes late, expect improvement to MVFR. Gusty nw winds to 20-25kt will occur tonight at all terminals.

(For the 4 AM Lake Superior forecast issuance)
Issued at 319 AM EST SAT DEC 9 2023

A compact area of low pressure lifting northeastward across the eastern Lake could lead to a short duration of some northwesterly gale gusts to 35 knots over the far eastern Lake near Whitefish Point and east late this afternoon. Then a cold front will sweep across Lake Superior this evening with winds shifting to the northwest with a few gale gusts to 35 knots likely especially across the north central part of the Lake. Winds will slowly diminish through the afternoon Sunday as ridging builds in from the west and persist through the day Monday. Another cold front approaching late Mon will cause southwest winds to ramp up to increase to 20-30kt by late afternoon. After the cold front passed late Monday night, west northwest gales between 40-45 knots are likely through much of the day Tuesday. Winds should be 30 knots or less Wednesday before another southwesterly gale is possible Thursday into Friday.

Upper Michigan...
Winter Weather Advisory from 5 PM this afternoon to 3 AM CST Sunday for MIZ009.

Lake Superior...
Lake Michigan...

Weather Reporting Stations
   EDIT       (on/off)   Help
Stations Dist Age Wind Air TempWater Temp WavesinHgDewPt
KP59 3 mi61 min WSW 4.1 42°F 29.5937°F
GTRM4 - Superior Grand Traverse Bay, MI 29 mi52 min NE 4.1G7 40°F 29.58
PCLM4 - Portage Canal, MI 37 mi72 min SSE 1G2.9 29.33
STDM4 - Stannard Rock, MI 42 mi52 min S 8G8.9
BIGM4 - Big Bay, MI 48 mi72 min 0G1 37°F 29.55

toggle option: (graph/table)

Wind History for Marquette C.G., MI
(wind in knots)    EDIT      (on/off)   Help

Airport Reports
    EDIT      (on/off)   Help   Click EDIT to display multiple airports. Follow links for more data.
AirportDistAgeWind ktVisSkyWeatherTempDewPtRHinHg
KP0 sm60 minWSW 04--43°F37°F81%29.57

Wind History from P59
(wind in knots)

Tide / Current for
   EDIT      (on/off)   Help

Weather Map
       (on/off)   Help

GEOS Local Image of great lakes   

Marquette, MI,

NOTICE: Some pages have affiliate links to Amazon. As an Amazon Associate, I earn from qualifying purchases. Please read website Cookie, Privacy, and Disclamers by clicking HERE. To contact me click HERE. For my YouTube page click HERE