


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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003 FXUS63 KIND 091702 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 102 PM EDT Thu Oct 9 2025 .KEY MESSAGES... - Sunny and Pleasant today with highs in the mid to upper 60s. - Dry weather is expected much of the time through next week, with the possible exception of a few showers Friday night - Temperatures will be near to slightly above normal much of the time && .FORECAST UPDATE... Issued at 1001 AM EDT Thu Oct 9 2025 Main focus for this morning`s forecast update is the frost potential tonight for portions of Central and North Central Indiana. High pressure remains the main influence over the region today and tonight resulting in a great set up for radiational cooling after sunset. A weakening pressure gradient, clear skies, and lighter winds should result in rapidly dropping temperatures after midnight. Some hi-res short term models indicate weak low level moisture advection in South Central Indiana as light winds become southeasterly, which may help keep tempertures elevated in the upper 30s to lower 40s. But for Central and North Central Indiana, including the Wabash River valley, higher confidence exists that lows may reach the 33-36 degree range in rural areas. Indianapolis`s urban heat island should prevent frost within Marion County. Frost headlines may be needed for tonight as confidence increases in the frost threat. && .SHORT TERM (Today and tonight)... Issued at 307 AM EDT Thu Oct 9 2025 Surface analysis early this morning shows strong high pressure centered over the Great Lakes and Ontario. The high was extending its influence across Indiana to KY and TN, as well as across the Mississippi Valley. GOES19 shows clear skies across Indiana and much of the region. Of note, some Lake clouds had formed with the ongoing cold air advection off of the Great Lakes. Looking aloft, Water vapor showed subsidence and drying across Indiana/IL and IA, including much of the plains states. this was due to a strong upper ridge axis found over MN, extending into western Ontario. Dew points were in the upper 30s and lower 40s with light NE winds. Today... Models suggests the strong ridge axis in place over MN will drift east across the Great Lakes and Indiana today, continuing to provide subsidence as the associated surface high also drift eastward. Forecast soundings show a dry column as these features pass with unreachable convective temperatures and an inversion aloft. Thus no CU will be expected and with protection from the ridge aloft, a sunny sky is expected. Cold air advection remains ongoing today, thus highs near persistence are expected. Tonight... Models show the ridging aloft exiting...allowing a northwest flow to remain ahead of another, stronger ridge over the Rockies, An upper level low is expected to push across Ontario and the northern Great Lakes with this feature, but those dynamics appear to remain well north of Indiana and will not impact our area. Meanwhile at the surface, the strong high pressure system is expected to push to the northeastern states, but a trailing ridge axis from the high will stretch west across Indiana, controlling our weather, while providing anti-cyclonic flow and subsidence. Again forecast soundings show a dry column. Thus a clear and cool night will be expected. Look for lows slightly warmer than persistence as warm air advection begins aloft. && .LONG TERM (Friday through Wednesday)... Issued at 307 AM EDT Thu Oct 9 2025 Dry conditions will continue to dominate the area during the long term period, with the possible exception of Friday night. A compact upper low will drop into the Great Lakes Friday night, stalling briefly before ejecting southeastward late Sunday. A moisture starved cold front will push through the area Friday night into Saturday, and a slight chance of showers will be possible primarily north on Friday night, though for the most part, an increase in cloud cover is the main expectation. Temperatures will fluctuate somewhat throughout the period, being near to slightly below normal early in the period, then a bit above normal early next week before moderating slightly again mid week. Lows will generally remain near to a bit below normal owing to enhanced diurnal ranges to be expected in ongoing drought conditions. && .AVIATION (18Z TAF Issuance)... Issued at 102 PM EDT Thu Oct 9 2025 Impacts: - None Discussion: High pressure will dominate the area during the period, leading to clear skies, unrestricted visibility, and winds less than 10KT. Winds will generally be easterly throughout the period shifting from 060-090 deg today to 180-210 deg tomorrow afternoon. There is a slight chance for fog at KHUF and KBMG tonight but confidence in this occurrence is low, so will not include it in the TAFs. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...CM SHORT TERM...Puma LONG TERM...Nield AVIATION...CM