textproduct: Northern Indiana

KEY MESSAGES

- Seasonable and dry today through Tuesday. Highs near 80 degrees.

- Big changes are ahead by midweek! A strong cold front will sweep through Wednesday afternoon through early Thursday, bringing chances for rain/storms and much cooler temperatures.

- Highs only in the 60s Thursday and Friday with near record lows well into the 40s.

- There is a Moderate Swim Risk for Lake Michigan Beaches in Berrien County, MI on Wednesday. There is a High Swim Risk for both La Porte County, IN and Berrien County, MI on Thursday.

DISCUSSION

Issued at 236 AM EDT Sun Aug 31 2025

With surface high pressure overhead, expect dry conditions to persist over the next several days. Mostly clear skies will allow for increased insolation today, which will boost temperatures up into the upper 70s to near 80 degrees. Given antecedent dry conditions, diurnal temperature spreads will be around 30-35 degrees with lows falling back into the mid to upper 40s tonight into early Monday morning under clear skies. To usher in the unofficial end of summer and begin meteorological fall, Labor Day will be very similar to today. Highs will be near 80 degrees area-wide on Monday with comfortable humidity and mostly clear skies. Enjoy the holiday weekend!

Big changes are ahead by midweek! For those awaiting another taste of fall, get your sweaters, flannels, and pumpkin spice lattes ready for Thursday! High temperatures will drop over 20 degrees between Wednesday and Thursday. An area of low pressure will drop into the Upper Great Lakes on Wednesday from western Ontario, with the system's attendant surface cold front and upper level trough extending throughout the Midwest. The strong cold front will sweep through the forecast area Wednesday afternoon through daybreak Thursday morning, bringing chances for showers and maybe even a rumble of thunder or two. Increased moisture out ahead of the front (dewpoints in the low 60s) may allow for a few prefrontal showers during the day Wednesday before the highest precipitation chances arrive with the front on Wednesday evening. As the upper level trough pivots through on Thursday and with a tight pressure gradient along and behind the front, expect gusty winds to accompany the sharp temperature drop late Wednesday into Thursday. With persistent northwest flow on Thursday and Friday, temperatures will only make it to the low to mid 60s for highs! Lows will be well into the 40s (with maybe a few low lying, rural locations making it into the upper 30s Friday morning? Very low confidence but something we'll have to keep an eye on.) It is worth noting that the GFS is much stronger than the ECMWF as to how cold it is on Thursday and Friday and how much temperatures can rebound by the weekend. The GFS suggests highs could be in the 60s until early next week with the Euro depicting a gradual return to the 70s over the weekend and into early next week. Have stuck with the NBM for now as it seems to be a good middle ground between the two.

Behind the strong cold front, breezy northwest winds and high waves will develop over Lake Michigan. There is a Moderate Swim Risk for Berrien County, MI beaches on Wednesday and a High Swim Risk for both Berrien County, MI and La Porte County, IN beaches on Thursday. Stay out of the water and stay off of piers/breakwalls! Strong rip and structural currents are expected in addition to the high wave action.

AVIATION /12Z TAFS THROUGH 12Z MONDAY/

Issued at 642 AM EDT Sun Aug 31 2025

Strong ridge of high pressure will remain over the Great Lakes maintaining VFR conditions and light winds. Expect just a few 4-5 kft diurnal cu today given dry/stable profiles.

IWX WATCHES/WARNINGS/ADVISORIES

IN...None. OH...None. MI...None. MARINE...None.