604 FXUS63 KIWX 092256 AFDIWXArea Forecast Discussion National Weather Service Northern Indiana 656 PM EDT Tue Sep 9 2025
.KEY MESSAGES...
- Temperatures in the mid to upper 70s and low 80s will climb into the mid-upper 80s by Friday, possibly persisting through the weekend.
- Dry with variable cloud cover through the work week. There are low chances (20 percent) for rain showers Sat night into Sunday. Isolated thunderstorms are possible.
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.DISCUSSION... Issued at 306 PM EDT Tue Sep 9 2025
Upper level ridging will build into the region, but it will face some challenges which may limit its eastward progress. The first challenge is with trough set to move through the region over the next 24 to 36 hours. While some showers and storms were present in southern MN, all signs have been for this to weaken with time as it runs into a much drier airmass with the best influx of low level moisture remaining to our west. Have continued with an increase in clouds but no precip.
In the wake of the trough, the ridge will attempt to build north and take hold, but faces a battle with 2 more northern stream waves. The initial wave is quite weak and simply bounces off the ridge with the model blend backing off on the previous slgt chc pops late Fri night into Sat. A deeper trough dives out of the James Bay area towards the SE Sat night into Sunday. Models have backed off on a closed low with a more progressive trough reaching Lakes Erie and Ontario by 6Z Sun as well as eventual phasing of the energy with the first trough set to impact the near term. Final solutions are all over the place on the location of the deepening low and possible impacts to the area. This shift has resulted in any pops now confined to 00Z Sun through 00Z Mon.
Outside of the impacts of these waves, high temperatures in the 80s will be common and if the GFS (more radical) solution verifies possibly into the 90s.
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.AVIATION /00Z TAFS THROUGH 00Z THURSDAY/... Issued at 653 PM EDT Tue Sep 9 2025
VFR conditions will prevail through this forecast period and beyond. Light winds and high clouds expected with a weak trough that will push through the region overnight.
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.IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None.
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DISCUSSION...Fisher AVIATION...Andersen
NWS IWX Office Area Forecast Discussion