


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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033 FXUS63 KIND 241818 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 218 PM EDT Sun Aug 24 2025 .KEY MESSAGES... - A very pleasant final week of climatological summer, with below normal temperatures and low humidity && .SHORT TERM (This evening through Monday)... Issued at 218 PM EDT Sun Aug 24 2025 Surface analysis this afternoon shows high pressure over the Dakotas with a ridge axis extending SE to MO/IL and Indiana. Cool northwest surface flow was in place across Central Indiana. GOES16 shows a large CU field across Central Indiana, resulting partly cloudy skies. Water Vapor shows strong subsidence in place across Central Indiana with northwest flow aloft. Dew points had fallen to the lower 50s due to mixing and subsidence. Tonight... Little change is expected in the overall weather as the surface high pressure to the west and along with continued subsidence will result in clear skies and light winds overnight. These conditions will also lead to good radiational cooling conditions and lows in the lower 50s. The last time Indianapolis had a low temperature of 55 or less was June 10. So tonight will be colder night that we have experienced in quite some time. Monday... Another partly cloudy day will be in store on Monday as NW flow aloft persists and surface high pressure remains in control of the weather at the surface. Forecast soundings show afternoon CU development as convective temperatures are reached. Thus after a clear morning, skies in the afternoon will become partly cloudy. Weak cold air advection will remain in place again on Monday as 850mb temps fall to 7C. This will result in highs mainly in the lower 70s. Overall, ongoing forecast is in good shape. && .LONG TERM (Monday night through Sunday)... Issued at 218 PM EDT Sun Aug 24 2025 Monday Night through Sunday... A persistent weather pattern will remain in place across the country this week. Models suggest strong upper ridging in place over the western United States, while a deep upper level low pressure system remains across Quebec and Ontario. This will continue to allow northwest flow aloft across Central Indiana. Subsidence will also be in place on the lee side of the ridge, helping to create a large area of surface high pressure that will allow a continued flow of cool, Canadian air across Central Indiana. A few upper short waves will pass within the flow across Indiana, but these systems will remained moisture starved and will only amount to a few passing clouds. Otherwise, we should expect a period of partly cloudy days and mostly clear nights in the week ahead. The coolest days will be on Tuesday and into Wednesday as the core of the coolest air arrives with 850mb temps around 5-7C. Warmer temperatures will arrive for Thursday and Friday as that cooler core drifts east. Through the week, highs will be mainly in the 70s, with upper 70s arriving by Thursday and Friday. && .AVIATION (18Z TAF Issuance)... Issued at 1151 AM EDT Sun Aug 24 2025 Impacts: - VFR conditions are expected this TAF period. Discussion: Strong high pressure will build across the TAF sites and maintain control over Indiana/s weather through the TAF period. Diurnal heating this afternoon and again on Monday will lead to some SCT-BKN cloud clover each afternoon. All clouds will be reside at VFR levels. Expect overnight to be clear with unlimited cigs due to the strong high pressure. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Puma LONG TERM...Puma AVIATION...Puma