Marine Weather and Tide Forecast for Manitowoc, WI

DISCUSSION
Issued at 105 PM CDT Sun Jun 7 2026

Fog...The fog bank over the middle of the lake has finally made it to the nearshore zones, mainly south of Kewaunee. Hi-res models have been absolutely terrible in modeling what will happen with this fog bank; therefore, confidence in its future placement is rather low. Current thinking is the fog bank should mix out this evening as winds increase across the lake. Satellite observations indicate this is already happening with the fog mixing out from north to south. Will keep the Marine Dense Fog Advisory for the lake through early this evening and assess as time goes on for a possible early cancellation.

Temperatures...Though warming trend remains in place for the upcoming week as heat ridge builds, gradually becoming less confident in seeing higher end heat indices (100+) during the middle to end of week timeframe. NBM seems to be coming in a few degrees hot with highs in the low to mid 90s during this time, though LREF ensemble shows mean temperatures in the mid to upper 80s with a fairly tight interquartile spread. Current thinking is that shower and storm chances in/around the area would hamper temps from rising to their full potential, though predictability of storm placement/coverage is low this far out. Nevertheless, can expect well above average (5 to 10 degrees) highs as subsidence under mid-level ridge brings 850 mb temps between 22 and 25C down to the surface. Would venture to say that headlines will be necessary at some point during the middle of the week given widespread moderate (level 2) to major (level 3) risk for heat- related impacts. If current temperatures hold, record to near- record high temperatures will be within reach Wednesday afternoon.

Rain/storm chances...A chance (60 to 90%) for widespread rain arrives Monday into Monday night as a fairly potent shortwave migrates through prevailing southwesterly flow and up into the Midwest. PWATs range between 1.75 and 2" during this time, nearing the absolute max relative to climo, so safe to say that periods of heavy rain can be expected. However, rain seems to have a more stratiform appearance during this time since organized convection appears unlikely due to absence of upper support and lack of surface forcing mechanism. However, embedded thunder will be possible as modest instability (~500 to 700 J/kg) pools near central Wisconsin. Any convection would be efficient rain producers in this moisture-rich environment, so will have to monitor for higher-end rainfall (1+") in this scenario. As it stands now, probabilistic guidance retains a 40 to 70% signal for receiving 0.5" of rain. Even at the higher end amounts, the flooding threat is not expected to be significant as soil moisture percentiles across much of the region are below 30% with much of the area in the D0 drought monitor so a heavy rainfall can likely be soaked in rather efficiently by the ground.

Active pattern takes shape during the middle to late part of the week as upper flow re-amplifies and several shortwaves propagate over the northern CONUS.

Severe weather risk...While the severe weather risk for the middle to late part of the week isn't clear, there is increasing confidence for strong to severe storms late Wednesday afternoon into Wednesday evening. The cold front moving through the western Great Lakes region is moving through during a favorable time, late afternoon into the evening, and has sped up from previous runs.
In addition, MUCAPEs are forecast to be around 2000 J/kg with bulk shear values ranging from around 25 knots in the Fox Valley to closer to 50 knots across north-central Wisconsin. Model soundings show thick CAPE in the Hail Growth Zone along with 1000 J/kg of DCAPE, indicating large hail and damaging winds are possible.
Abundant low level turning in the hodographs and LCL heights below 1000 m indicate tornadoes are not out of the question.

The best potential for severe weather appears to be in the western portion of the CWA out in central and north-central Wisconsin given the earlier timing where instability and shear will be maximized. The severe weather threat drops off as you go further east towards the Fox Valley and lakeshore given less favorable shear and a later arrival of the storms, which would mean instability would not be as high. The timing of the front will play a large role, so any further adjustments in the timing of the front will alter the severe weather risk Wednesday afternoon and Wednesday evening.

Another round of storms is slated to move through the region on Thursday. However, the severe weather potential for this day will likely hinge on what happens with the system on Wednesday and Wednesday night. Therefore, it is too early to ascertain what will happen this far out.

AVIATION
for 00Z TAF Issuance Issued at 547 PM CDT Sun Jun 7 2026

VFR conditions will continue into Monday morning as mid and high clouds will continue to be on the increase overnight. A band of showers will move across the area later Monday morning into the afternoon. May need to add thunder in the 06z tafs for KAUW/KCWA.
There will be a break in the rain behind the first round, with a steadier round of showers and storms later in the afternoon into the evening. CIGS are likely to drop into the MVFR or lower category later Monday afternoon and Monday night. Fog will be possible Monday night.

GRB WATCHES/WARNINGS/ADVISORIES
None.