Marine Weather and Tide Forecast for Sturtevant, WI

UPDATE
Issued 1045 AM CDT Mon Jun 16 2025

The current shower activity across south central Wisconsin continues to linger and is slowly spreading east, though it is moving into drier air. The differential CVA with the 500 mb shortwave trough may linger into this afternoon, which would keep the showers going. Building instability may bring a few storms as well. May need further adjustments in eastern parts of the area to keep the showers and a few storms going this afternoon.

There is a broken line of thunderstorms north to south in east central to south central Minnesota, being driven by surface to 850/700 mb warm air advection and perhaps some frontogenesis response in this area. CAMs are really struggling with grabbing onto this activity. These storms may shift eastward into this afternoon, reaching western portions of the forecast area after around 4 PM CDT this afternoon. This could linger into early this evening, with brief gusty winds and small hail possible with deep layer bulk shear up to around 20 knots and mean layer CAPE of up to 1000 J/kg. Will adjust PoPs later this afternoon and early this evening to reflect this activity.

CAMs continue to show some potential for a line of storms moving southeast toward and into the area this evening and perhaps lingering into the overnight hours. There is a lot of uncertainty here with if and how much thunderstorm activity will affect the area during this time. Some CAMs bring this activity into the area and weaken it as it pushes through, with others weakening before it gets into the area or are dry altogether.
Will maintain PoPs for this possibility, but again confidence is rather low with what may occur.

Wood

SHORT TERM
Issued 330 AM CDT Mon Jun 16 2025

Today and Tonight:

An MCV feature continues to stick around over the southwest parts of WI this morning and appears likely to hang around at least for the next several hours. This will keep shower chances through the early morning hours as it slowly migrates north.
There is some potential for storm development over the next few hours with this as instability increases as the sun comes out as we start to diurnally heat. We will continue to monitor over the next few hours for additional development.

The morning and early afternoon hours will for the most part keep much of the CWA dry but the western fringes will keep some shower/storm risk with a shortwave pushing across the area but with decreasing low to mid level moisture further east dry air will likely inhibit much in the way of showers or storms further east, particularly into the early afternoon.

Into the late afternoon and evening hours we will see another shortwave slide through but this one looks to be associated with better low to mid level moisture and will benefit from additional forcing from the frontal feature sliding across the region associated with the low pushing east across the northern Great Lakes region. There is at least a decent chance for stronger storms with this despite the potentially later timing given some instability and modest deep layer shear. Some CAMs have shown support for the development of an MCS feature in southern MN and northern IA that would potentially push into southern WI overnight but there remains a lot of uncertainty with that risk as a few CAMs show nothing at all but this will be worth monitoring to our west later today. However as with the previous days the drier air further east as well as the instability dropping further into the evening eastern parts of the CWA may remain dry overnight and this could result in a remnant MCV feature if an MCS were to occur withing the region.
This will may especially be the case as the front somewhat stalls overnight over the CWA between the departing low to the north and the developing low in the Central Plains.

Kuroski

LONG TERM
Issued 330 AM CDT Mon Jun 16 2025

Tuesday through Sunday:

Overall, model ensembles are in pretty good agreement with the expected upper level pattern evolution into next weekend. As is typically the case with these summertime patterns, the devil is in the mesoscale details from day to day.

The door remains open to remnant MCS activity Tuesday as a low level boundary will either be overhead or very nearby. Certainly not enough confidence in a washout scenario, but there are chances for periodic showers and storms in a warm and muggy airmass.
Unlike the past couple of days, low level westerly winds will, for at least a time, allow areas adjacent to Lake Michigan to warm into the 80s.

The best opportunity for showers/storms is still centered on Wednesday/Wednesday night. Timing differences continue to exist with the Canadian/European ensembles about 6-12 hours faster than the GEFS. The main consequence of this discrepancy is whether we can muster enough instability with increasing shear to result in a risk for severe storms. In the end, this is a mesoscale problem, with a whole host of possible caveats. Keep an eye out for at least a few storms to produce a wind/hail risk.

High pressure attempts to build into the region Thursday, though northwest flow on the back edge of the departing upper wave keeps the door open to diurnally driven showers and a few storms. The influence of this high will be very short lived as a warm front will quickly approach from the southwest heading into Friday as the upper level pattern amplifies. Expect additional, periodic rain chances associated with the warm front Friday/Friday night.

The summer solstice arrives at 941 PM CDT Friday evening, and right on queue, summertime temperatures arrive on Saturday. A deepening trough over the western CONUS will promote increased ridging aloft. The ensembles only offer minor differences with this pattern, mainly focused on the amplitude of the ridging over the central and eastern CONUS. This does bear watching as it governs just how far north the resultant storm track will set up.

As it stands right now, the storm track looks to set up to our north (per Canadian/European ensemble mean), with temperatures surging to well above average levels. The NBM probabilistic guidance indicates a 50% chance of highs at or above 90 degrees over much of the area. With dewpoints in the mid/upper 60s, this will feel very much like the heart of summer with heat index values well into the 90s, especially inland areas. Bottom line, watch out for increasing heat impacts next weekend.

Gagan

AVIATION
Issued 1045 AM CDT Mon Jun 16 2025

The current shower activity across south central Wisconsin continues to linger and is slowly spreading east, though it is moving into drier air. This may continue to linger this afternoon and may spread toward the lakeshore terminals. A few storms may occur as well. May see visibility reductions to 4 to 5 miles at times and ceilings around or below 2000 feet in more persistent rain areas.

Light south winds are expected into this afternoon, with a southeast lake breeze developing by early afternoon for the terminals near Lake Michigan. Ceilings should remain above 3000 feet AGL during this time.

There is a broken line of thunderstorms north to south in east central to south central Minnesota, and may shift eastward into western portions of the forecast area after around 4 PM CDT this afternoon. This could linger into early this evening. For now, may add in PROB30 groups for this activity later this afternoon and early evening for the Madison and Janesville terminals. Not sure if this will move all the way east to the rest of the terminals.

There is some potential for a line of storms moving southeast toward and into the area this evening and perhaps lingering into the overnight hours. There is a lot of uncertainty here with if and how much thunderstorm activity will affect the area during this time. Confidence is low, so will not mention in TAFs at this time.

Winds will be light and south tonight, then southwest on Tuesday, as a cold front moves into the area from the northwest in the afternoon. Winds should shift west behind the front.
There are chances for showers and storms with the front, mainly Tuesday afternoon and evening.

Wood

MARINE
Issued 1045 AM CDT Mon Jun 16 2025

High pressure around 30.2 inches well east of the region will combine with low pressure around 29.8 inches over the northern Plains to bring southerly winds today. Winds will turn increasingly breezy, particularly on the north side of the lake this evening into Tuesday, as the low crosses the northern Great Lakes region. This will bring chances for thunderstorms.

Another low pressure system around 29.5 inches will approach the region from the central Great Plains on Wednesday, with continued thunderstorm chances. The exact trajectory of this low will determine winds on Wednesday, but for now, southerly winds are forecast for the south half of the lake and easterly winds for the north half.

Kuroski/Wood

MKX WATCHES/WARNINGS/ADVISORIES
WI...None.
LM...None.