Marine Weather and Tide Forecast for New Buffalo, MI

DISCUSSION
Issued at 409 PM EDT Sun Sep 20 2026

Opted to extend the flash flood watch until 2 am EDT for areas further south and east given expected rainfall through late tonight- which is where most of the rain has fallen over the past week and impacts linger. Additional totals of 1-2" are possible through Monday morning as a shortwave or two move through, which could exacerbate any flooding in these areas. Much of the high res develops heavier rainfall within some more convective elements this evening, however as of this writing we are pretty meager in terms of heavy rain. Expect a period of isentropic ascent to continue through at least the evening as a low pressure system develops along the stationary front with this first shortwave. Still have decent warm cloud depth, pwats around 2" and a LLJ of around 25-30 knots, so heavy rain is still a possibility. Thunderstorms are also possible.

Otherwise, expect a drying trend late Monday into the rest of the week, with mainly intermittent low chances (20-30%) as we sit on the periphery of upper level ridge/upper low, with surface high pressure below (particularly Thursday into the weekend). It will be more fall like, with highs in the 60s, low 70s and then lows falling into the upper 40s, 50s. By the weekend, we warm up into the low-mid 70s (warmest Sun).

AVIATION /18Z TAFS THROUGH 18Z MONDAY/
Issued at 137 PM EDT Sun Sep 20 2026

A low level confluence zone in advance of a southward sinking boundary aided in showers/storms this morning across northern Indiana. A lull in greater rain shower developed late morning/early afternoon but an advancing convectively enhanced short wave from northern Illinois is associated with another area of rain that will overspread terminals this afternoon. The instability gradient remains parked roughly along the US Route 30 corridor, so cannot completely discount some scattered convection and some thunder potential at KFWA for a time in the 20Z-23Z timeframe, but confidence in this scenario is somewhat low. IFR cigs are expected at terminals through this evening with eventual north to south improvement late evening into Monday morning as baroclinic zone sinks southward and low level dry air advection overspreads southern Great Lakes. MVFR cigs will likely persist into Monday morning at KFWA however.
Deepening northeast flow and some increase in mixed layer with cold advection will support northeast gusts to around 20 knots at times.

IWX WATCHES/WARNINGS/ADVISORIES
IN...Flood Watch until 2 AM EDT Monday for INZ017-018-023>027- 032>034.
OH...Flood Watch until 2 AM EDT Monday for OHZ015-024.
MI...None.
MARINE...None.