Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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011 FXUS63 KIND 251953 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 253 PM EST Tue Nov 25 2025 .KEY MESSAGES... - Rain showers continue into tonight, transitioning to snow showers on Wednesday. - Wind Advisory in effect from 7am to 7pm Wednesday, winds 20-30 mph with gusts 40-50 mph expected. - Wind chills in the teens Thursday and Friday. - Potential for accumulating snow Saturday to Sunday with colder weather persisting into early next week. && .SHORT TERM (This evening through Wednesday)... Issued at 252 PM EST Tue Nov 25 2025 A cold front extends from Minnesota southward through Iowa and into Missouri as of 2pm. The air mass ahead of the cold front is rather mild and humid, with rich moisture in the lower levels. This has lead to modest amounts of instability primarily confined to under 3km. The shallow instability, combined with weak lift, has lead to scattered light rain showers this afternoon. These should continue through this evening and into the overnight. The cold front itself looks to arrive around 3-6am. High-resolution guidance hints at a line of heavier showers immediately along the boundary. Given the modest low-level instability present, this does not appear unreasonable. Some of these showers may even produce some gusty winds. Winds should remain elevated even after the showers pass. The MSLP gradient behind the front is expected to tighten considerably as low pressure to our north intensifies. Increasing surface pressure gradient is one factor for gusty winds on Wednesday. The other is steep boundary layer (PBL) lapse rates which will promote efficient downward momentum transfer during the daylight hours. Guidance has gradually trended upward regarding winds at the PBL/free atmosphere interface, so we`ve nudged wind speeds up a bit compared to our previous forecast. Additionally, we`ve issued a Wind Advisory for the majority of our CWA. Expect sustained winds between 20-30mph with gusts 40-50mph. Steep lapse rates, broad cyclonic curvature, and rich PBL moisture will lead to continued precipitation potential on Wednesday. However, as temperatures continue to cool from strong cold air advection within the post-front environment, a transition to mostly snow is expected. Accumulations are not expected. Most of the snow on Wednesday will be either flurries or light snow showers. Temperatures are expected to peak before sunrise Wednesday, gradually falling through the 30s during the day as cold air advection continues. Wind chills look to be in the upper 10s/20s through the afternoon. && .LONG TERM (Wednesday night through Tuesday)... Issued at 252 PM EST Tue Nov 25 2025 Wednesday Night Through Friday. By Wednesday night the stronger pressure gradients will begin to relax along with a decoupling of the boundary layer which will bring an end to the gusts of 40 to 50 mph. Drier air will also work into the area which will help to erode the residual clouds and help to bring temperatures down into the low to mid 20s across central Indiana with wind chills in the teens. Breezy conditions will return during the daytime hours Thursday with gusts of 20-30 mph and wind chills remaining in the teens through the day. Similar conditions are expected for Friday with mostly clear skies, breezy conditions and chilly temperatures. Saturday Through Tuesday. The main focus for the long term period will be tracking the potential for an accumulating snow Saturday into Sunday. While many of the finer details remain uncertain, the broader details are beginning to become a bit more clear. Synoptically, an upper level shortwave will push southeast out of the Northern Rockies with weak southeasterly surface flow just ahead of the arrival of the low. Confidence is increasing in the surface low track with broad model agreement in central Indiana remaining in the "warm" sector of the system as the low tracks from Missouri through Northern Illinois and Lake Michigan. Where details are still more uncertain and impactful will be surface temperatures ahead of the arrival of precipitation and the impacts on precipitation type. Latest trends over the last 12 hours have been trending towards the GFS on timing with a less progressive low pressure system with precipitation onset potentially as late as the late morning/early afternoon hours on Saturday. Confidence is fairly high in snow being the initial precipitation type before stronger southerly flow advects warmer air into central Indiana through the night. This non-diurnal temperature curve will help to transition the snow to rain at some point during the night with overall snow totals looking on the lower end compared to other recent model runs due to the later precipitation onset time. That being said, at least some travel impacts look likely during the afternoon and evening hours Saturday with surface temperatures in the upper 20s to low 30s ahead of onset with no expected issues for the snow to stick as temperatures will be well below freezing in the days leading up to Saturday. It remains very uncertain on specific snowfall totals, but a reasonable expectation at this time looks to be 1-2 inches across north central Indiana with 0-1 towards Indianapolis and points to the south. There remains the potential for both higher amounts and an all-rain scenario but those look to be the less likely scenarios at this time. Snow ratios will also likely end up on the lower end of normal at around 6-8:1 due to the wet/slushly nature of the snow. Going into Sunday much cooler temperatures will quickly move in as the low moves into the Great Lakes and much colder air pushes in on the backside of the system. There will be at least some mid-level forcing on the backside of the system which will bring the potential for additional snow chances through the day Sunday with some signs of lingering flurries into Monday. Temperatures will then remain below normal through Tuesday with another low-end chance for additional snow Monday night into Tuesday. && .AVIATION (18Z TAF Issuance)... Issued at 1236 PM EST Tue Nov 25 2025 Impacts: - Sub-IFR ceilings for most of the day with subtle improvement to MVFR this evening - Light showers possible ahead of and along a cold front tonight - Westerly winds increase pre-dawn Wednesday with peak gusts 30kt to 40kt - Light snow showers and flurries during the day Wednesday Discussion: Rain has ended across central Indiana though IFR ceilings remain. Some gradual improvement to MVFR is likely as we head into tonight. A cold front is approaching from the west, which arrives tonight, and will bring a few showers and scour out any remaining IFR ceilings. Low stratocumulus quickly builds back in behind the front, with MVFR ceilings persisting through the TAF period. Additionally, flurries and light snow showers are possible throughout the day Wednesday as colder air filters in. Brief minor visibility reductions are possible. A substantial increase in wind speeds is likely after the front passes through. Winds will initially be out of the SW tonight before becoming Westerly on Wednesday. Sustained winds between 20kt to 30kt with gusts up to 40kt possible. Winds will then gradually diminish after sunset Wednesday. && .IND WATCHES/WARNINGS/ADVISORIES... Wind Advisory from 7 AM to 7 PM EST Wednesday for INZ021-028>031- 035>049-051>057-060>065-067-068. && $$ SHORT TERM...Eckhoff LONG TERM...White AVIATION...Eckhoff