Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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912 FXUS63 KIWX 222330 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 730 PM EDT Wed Jul 22 2026 .KEY MESSAGES... - High waves and strong currents are expected at southeast Lake Michigan beaches today through tonight. Stay out of the water and off of piers! - Dry, cooler, and less humid conditions expected into the weekend. - Warmth and humidity returns Sunday and Monday, which also happens to be when the next chance for storms (20-40%). && .DISCUSSION... Issued at 142 PM EDT Wed Jul 22 2026 Behind yesterday`s cold front, surface high pressure noses into the area and continues affecting us with drier conditions and below normal temperatures until Saturday. Looking at NAEFS climatology between mid July and early August on the Ensemble Sit Table, 850 mb temperatures cooler than 8C happens about once in every 10 yrs or so in parts of N IN and NW OH midday today. The coolest night in this period is tonight and then we slowly warm with lows back above 60 degrees again Saturday night. A strong theta-e plume pushes back through the area midday Saturday with 70 degree dew points returning overnight and 850 mb temperatures achieving 18+C again by Sunday morning. At this point, we have a ridge over the western US and a trough over the eastern US, putting our area in a northwest flow regime, which would seem to indicate the possibility of MCSs or ridge riders. Sunday morning has what appears to be an outflow boundary or at least some sort of temperature gradient entering the area. Then there appears to be a more concrete upper PV anomaly associated with upper divergence and sfc convergence on the GFS (with some model confluence from the ECMWF with having a similar PV anomaly moving through Sunday morning) that usually occurs in the vicinity of MCSs perhaps indicating the potential for such an occurrence Sunday afternoon depending on the state of the area after the morning outflow boundary. We actually have some effective shear around on Saturday into Saturday night, but instability appears rather weak at less than 1000 J/kg. Shear is gone by the time we get into Sunday though. Perhaps another opportunity for stronger storms is some time on Monday. The GFS has better shear in the morning with thermal boundaries around as well as instability. The WxNext AI model indicates the best chance for severe weather is that Monday time frame. && .AVIATION /00Z TAFS THROUGH 00Z FRIDAY/... Issued at 727 PM EDT Wed Jul 22 2026 VFR prevails. Skies will continue to clear this evening, giving way to mainly SKC conditions overnight into early Thursday. VFR cumulus developing again by Thursday afternoon. Light winds will persist through the TAF period as high pressure takes control. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Beach Hazards Statement through Thursday morning for INZ103. OH...None. MI...Beach Hazards Statement until 1 AM EDT Thursday for MIZ177-277. MARINE...Small Craft Advisory until 1 AM EDT Thursday for LMZ043-046. && $$ DISCUSSION...Roller AVIATION...Hammer