Marine Weather and Tide Forecast for Constantine, MI

DISCUSSION
Issued at 224 PM EDT Sun Apr 12 2026

Cloud cover has quickly cleared out with a rapid upward trends in temperatures today with many locations enjoying the 70s. These temperatures will dominate much of the upcoming week as the overall upper level pattern remains unchanged with a trough across the western US and a unimpeded southwest flow ushering in warmth and moisture. A series of disturbances will eject from the trough, the first arriving this evening. This feature is currently highlighted by an area of showers and a few storms across western Missouri. This will move northeast into tonight, bringing increasing chances for showers and maybe a storm or 2 this evening and maybe into the overnight hours before quickly moving away. Some models trend with an overall weakening of the area as it outruns the better lift, but most areas should see some measurable rainfall (not enough to cause any additional hydro issues).

Some changes to pops have occurred through the day Monday and even into Mon night and early Tuesday to match with a converging of trends wrt to axis of best precip chances most likely north (if not well north) of the forecast area. In the wake of tonight's wave, there will be little in the way of forcing around Monday until the next wave approaches and by in large misses the area to the NW.
Temps in the 70s and dewpoints in the 60s will allow for 1K to maybe 2K of SBCAPE and modest low/mid level lapse rates. With the lack of any trigger, convective potential would be very isolated, if at all through Monday afternoon. An increasing LLJ to the west and another disturbance will set the stage for shower and storm development with the greatest threat across WI into central Lower MI near the warm front. Still appears there could be a few showers and storms around Monday evening across far northern areas, but could see pops getting whittled down further in future forecasts.

Tuesday into Wednesday appear to be the potentially busier days, but not clear cut in terms of severe or flooding potential. With the bulk of the precip expected to be north of the area to start Tuesday, this would set the stage for better heating and plenty of instability around for Tuesday afternoon and evening. With the more northward trend in the best chances of convection Mon ngt/early Tues this could lead to a lack of convective boundaries around to allow early initiation Tuesday afternoon. This would mean we may need to wait till the next disturbances moves in Tuesday night with increasing chances for showers and storms in the NW third to maybe half of the area. With the main surface features still to the north and west, the greatest focus for severe weather could materialize well away with convection then moving in during a less favorable window overnight into early Wed. Only minor changes made Tuesday night given the low confidence on any 1 scenario. If stronger storms take shape, all modes would be possible (leaning towards hail or wind damage). Wednesday relies heavily on Tuesday nights outcome as the main cold front will still remain well west of the area and the sfc low working north across MI. The upper level trough will begin to eject and intensify somewhat with general consensus of the wave in eastern NE at 00Z Thu then to WI by 18Z Thu. The greatest severe threat likely will reside to our west once again (as highlighted by the DY4 15% area from S WI into NE TX). No changes for Wednesday into Thursday given the uncertainty.

Yet another northern stream trough will dig into WY/CO by 12Z Fri with a uptick in the low level flow to usher in potentially the first day of more widespread 80 degree temps across portions of the area. A leftover front may exist to cause somewhat of a gradient north to south but still well above normal even north of it (mid to upper 70s). Rain chances look to increase Friday night into Saturday as the trough moves across the area and pushes a strong cold front with it. Highs Sunday are likely to be 15 to 25 degrees cooler than Sat.

AVIATION /00Z TAFS THROUGH 00Z TUESDAY/
Issued at 728 PM EDT Sun Apr 12 2026

With high pressure to the east and low pressure to the west, the area is squarely in warm advection. This brings a shortwave from N MO into the southern tear drop of Lake MI between 0 and 6z tonight, which pushes showers and potentially some thunderstorms through the area between 00 and 12z tonight. Severe weather chances appear low, however. Will continue the tempo group mention of MVFR conditions at SBN for these storms as well as prevailing MVFR CIGs entering behind these storms and continuing into the morning hours. Capping and or the lower ceilings probably restricts any pop shower or storm until the late afternoon/evening, if at all on Monday.

One thing to watch in this setup is LLWS. Low level lapse rates crash not too long after 23z this evening so LLWS could ramp up as early as taf start. The LLJ departs the area around 12 to 15z and low level lapse rates ramp up again Monday morning allowing the LLWS threat to end. Better low level lapse rates reside across FWA area Monday allowing gusts to around 25 kts to be possible while SBN probably only sees sustained winds greater than 10 kts as opposed to 25 kt gusts.

IWX WATCHES/WARNINGS/ADVISORIES
IN...None.
OH...None.
MI...None.
MARINE...Small Craft Advisory until 8 AM EDT Monday for LMZ043-046.