


Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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678 FXUS63 KIWX 091654 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 1254 PM EDT Wed Jul 9 2025 .KEY MESSAGES... - Becoming hot and humid Friday and Saturday. Highs in the upper 80s with heat indices in the low to mid 90s. - Chances abound for mainly afternoon and evening showers and thunderstorms through early next week. - Severe storms are not expected. && .DISCUSSION... Issued at 258 AM EDT Wed Jul 9 2025 Incredibly stable mid level (700mb-500mb) lapse rates in the order of 4.7 to 5.0 C/Kg were over northern Indiana and surrounding areas. Scattered showers and a few storms have survived the night in the base of the upper level trof that was moving through the Upper Great Lakes region. Scattered showers and storms will become more numerous by late this afternoon with daytime heating. Severe storms are not expected, but locally heavy rainfall and wind gusts up to 40 mph will be possible. There should be a short break in the activity Thursday with somewhat more stable air, slightly lower dew points and weak subsidence. An upper level trof topping the subtropical ridge extension was over the southwest CONUS will phase with another wave moving east across southern Canada. These merging systems will bring a good chance for showers and storms Friday. Given the stable conditions, heavy rainfall is not expected. After Friday, numerous chances for showers and storms will persist through the middle of next week given the environment of high precipitable water values and deep moisture. && .AVIATION /18Z TAFS THROUGH 18Z THURSDAY/... Issued at 1248 PM EDT Wed Jul 9 2025 Scattered showers and a few thunderstorms are ongoing this afternoon in the warm sector of an approaching low over eastern Michigan. KSBN is on the western fringe of this activity with the most robust cumulus development noted to their east and south. Not enough confidence to offer a dry forecast there, thus, I`ve retained the inherited -TSRA mention. Confidence is higher at KFWA for thunderstorms this afternoon, though existing cloud cover has limited instability somewhat. In the wake of showers and storms, fog appears to be increasingly likely with renewed low level moisture, weak flow, strong model concensus and a slow-moving front. Fog is less certain at KSBN where, like existing satellite trends above, they are on the western fringe of fog in model guidance. This trend will need to be monitored for the next issuance. For now, held onto the prevailing VFR conditions at KSBN. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...Beach Hazards Statement from 4 PM CDT this afternoon through late tonight for INZ103. OH...None. MI...Beach Hazards Statement from 5 PM EDT this afternoon through late tonight for MIZ177-277. MARINE...None. && $$ DISCUSSION...Skipper AVIATION...Brown