Marine Weather and Tide Forecast for Bayfield, WI

DISCUSSION
Issued at 412 AM CDT Thu May 22 2025

Relatively quiet forecast on tap for the next 7 days. Afternoon RH values and overnight low temperatures are the greatest concerns. Temperatures will trend warmer over the next 7 days.

Early this morning skies were clearing across the Northland.
Temperatures were falling. Areas with the lightest winds have dropped into the low 30s and upper 20s. Hibbing may tie or break their low temperature for today. The current record is 27 degrees and at 4 AM the temperature was 29 degrees.

A high latitude Omega Block remains in place across much of Canada. The eastern cutoff low was located over Ontario and Quebec. Split flow was found over the continent and the main branch of the subtropical jet stretched from the northern Pacific coast into the Carolinas and Georgia. A subtle ridge will propagate eastward into the northern Plains and portions of the Upper Midwest tonight. The blocking pattern will slowly break down over the weekend although little chance in sensible weather over the Northland is expected.

At the surface a broad area of high pressure was centered over Hudson Bay and will slowly sag southward over the next week.
Drier air from northern latitudes will continue to advect into the region and will contribute to low afternoon RH values below 30 percent, probably through the weekend at least.

Mostly sunny skies will result in deep boundary layer mixing giving rise to wind gusts of 15 to 20 mph over land areas today and again on Friday.

A pool of cooler 850 mb temperatures will drift southwestward from Hudson Bay toward the Arrowhead of Minnesota this afternoon. The approaching subtle upper-level ridge will result in marginal deepening of the trough over the Midwest and a small increase in large scale ascent. Along with the cooler temps aloft, these two factors may be sufficient to generate isolated showers or sprinkles this afternoon and evening. High temperatures today should be in the middle 50s in Cook County and over eastern portions of northwest Wisconsin (Iron and Price counties).

Clear skies and light winds tonight will make frost possible once again. We issued another Frost Advisory for tonight as a result of high confidence in the conditions. Lows tonight will range from around 37 degrees to around 30 degrees. Typically colder spots may record low temps in the 20s. Hibbing may make another run at a record low temperature Friday. Current record low for May 23 is 26 degrees.

A west-northwesterly upper-level jet streak will strengthen over the Midwest on Friday which should reinforce the high pressure over the region since Minnesota and Wisconsin will be under the left entrance region of the streak. There could be a few isolated showers or sprinkles again Friday afternoon in the Arrowhead. Low RH will return Friday and Saturday afternoons.
Temperatures will trend a degree or two warmer each day through Sunday. There will continue to be a small chance of isolated sprinkles or light showers each afternoon with the best chances in the Arrowhead.

Early next week a split flow pattern returns. The northern branch of the jet will be over northern Canada and the southern branch will be over northern Mexico and the Gulf Coast curving north into the Canadian Maritimes. That places the Upper Midwest between the two air streams. High pressure will continue to be the main story. Low afternoon RHs are possible and temperatures will gradually warm through the week. There are no appreciable chances of widespread precipitation over the next 7 days.

AVIATION /12Z TAFS THROUGH 12Z FRIDAY/
Issued at 639 AM CDT Thu May 22 2025

Mostly clear skies expected today. Winds will be gusty this afternoon and will subside around 23.01Z. There is a small chance of fog developing at BRD and HYR tonight, though the probabilities are too low to include in the forecast at this time.

MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/
Issued at 412 AM CDT Thu May 22 2025

Surface high pressure over Hudson Bay sag slowly southward over the next 48 hours. Northeast winds persist, although sustained winds will generally be 12 knots or less and gusts will be less than 16 knots. No hazardous conditions are expected over the next 4 days.

For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt.

DLH WATCHES/WARNINGS/ADVISORIES
MN...Frost Advisory until 9 AM CDT this morning for MNZ010>012- 018>021-025-026-033>038.
Frost Advisory from 1 AM to 9 AM CDT Friday for MNZ010>012-018- 019-025-026-033>038.
WI...Frost Advisory until 9 AM CDT this morning for WIZ001>004- 006>009.
Frost Advisory from 1 AM to 9 AM CDT Friday for WIZ001>004- 006>009.
MARINE...None.