Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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993 FXUS63 KIND 261855 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 155 PM EST Wed Nov 26 2025 .KEY MESSAGES... - Wind Advisory in effect 700 AM - 700 PM today for westerly winds of 20-30 MPH and gusts of 40-50 MPH - Flurries through the evening with a few snow showers this afternoon - Wind chills in the teens tonight, Thursday night, and Friday night - Threat continues for accumulating snow Saturday before a gradual changeover to rain by early Sunday - Much colder air to open December with additional opportunities for wintry weather && .SHORT TERM (This evening through Thursday)... Issued at 154 PM EST Wed Nov 26 2025 Observational data and satellite imagery show a strengthening surface low over northern Lake Michigan as of 1pm. A very tight MSLP gradient has developed around the low, and especially to its southwest. This has lead to strong winds with frequent gusts between 40 to 50 mph. Frequent wind gusts over 40 mph continue into this evening as boundary layer (PBL) mixing deepens allowing for greater downward momentum transfer of faster flow aloft. A Wind Advisory for gusts between 40-50mph remains in effect until 7pm. Lapse rates within the PBL are also steepening, which has lead to enough shallow convective instability for flurries and light snow or graupel showers. With broad cyclonic flow in place, we expect precipitation to expand in coverage this afternoon. Surface temperatures are in the mid to upper 30s as of 1pm. Despite this, snow and graupel will be the primary precip type today. The reasons include the aforementioned steep lapse rates. Shallow convective forcing should allow for riming at times, which leads to graupel. It`s also quite cold just above the surface so any snow/graupel will not need to fall through a significantly deep warm surface layer. Additionally, soundings and observations show the surface layer to be rather dry as well. This will help reduce the effects of melting through evaporational cooling. Snow flurry/shower activity is expected to diminish quickly around sunset as instability is lost. Winds will likewise begin to die down as the PBL becomes more stable. However, a tight MSLP gradient remains in place and winds should continue to be on the breezy side through the night. Cold air advection continues through the night as well with temperatures falling into the low to mid 20s. Combined with the wind, wind chills may drop to as low as 10-15 degrees. Thanksgiving By tomorrow morning, the low over Lake Michigan will have moved eastward allowing the MSLP gradient to relax. Even with the downward trend, winds should remain elevated through the day. Frequent wind gusts between 20-30 mph appear likely. As mentioned above, wind chills are expected to be quite cold. Values as low as 10 degrees are possible through the morning hours. High temps top out around freezing for the northern half of our CWA, with mid to upper 30s further south. Cloud cover looks to be less compared to today, with stratocumulus lifting northward overnight. Clouds may temporarily drop southward again during the day tomorrow before slowly dissipating overnight into Friday morning. Flurries are still possible Thursday but mainly downwind of Lake Michigan. This places only our far northeastern counties under any chance to see flurries on Thanksgiving. && .LONG TERM (Thursday night through Wednesday)... Issued at 154 PM EST Wed Nov 26 2025 Thursday Night Through Saturday. The main focus for the long term period will be tracking the potential for an accumulating snow Saturday. Ahead of the snow, the breezy winds Thursday will gradually relax during the overnight with winds generally in the 10-15 mph range, but as temperatures fall wind chills will remain in the teens through the day on Friday. While many of the finer details remain uncertain on the Saturday system, the broader details are becoming 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 trended back southward concerning the rain/snow line with generally cooler antecedent conditions. The GFS continues to look a bit unmeteorological with snow well into the warm sector and weaker WAA near precipitation onset and continuing until the early overnight. Confidence remains 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. That being said, at least some travel impacts look likely during portions of the afternoon and evening hours Saturday with surface temperatures in the upper 20s to low 30s ahead of onset and 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 2-4 inches across north central Indiana with 1-2 towards I-70 and 0-1 in points to the south. There remains the potential for both higher amounts up to as much as 6 inches in the worst-case scenario, especially towards Lafayette. With the latest trends, the potential for the event being all rain looks increasingly unlikely. Much of the impacts will be over a 6-8 hour window beginning sometime in the late morning/early afternoon hours with impacts lessening towards midnight. Sunday Through Wednesday. 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 rain/snow chances through the day Sunday with some signs of lingering flurries into Monday. Temperatures will then remain below normal through Wednesday with another low-end chance for additional snow Monday night into Tuesday while areas to the south of central Indiana may see potential heavy rain. && .AVIATION (18Z TAF Issuance)... Issued at 1222 PM EST Wed Nov 26 2025 Impacts: - Strong westerly winds through today, gustiness continuing tonight into Thursday - A few periods of brief, light flurries at times Discussion: VFR conditions are expected throughout the period, though a brief drop to the MVFR borderline cannot be entirely ruled out, primarily at LAF. The primary concern for this period will be winds, with sustained winds of 20-28KT and gusts to around 40KT through this afternoon at all sites, generally from 260-270 degrees. Winds will die down a bit this evening, particularly gust speeds, but remain gusty throughout the night and into Thursday. Direction will veer slightly later in the period to 280-290, with gusts dropping back into the low to mid 20s range tonight with sustained winds in the mid teens. A few flurries are occurring, though at any one site these will be transient and should cause no restrictions. No obstructions to visibility are anticipated through the period. && .IND WATCHES/WARNINGS/ADVISORIES... Wind Advisory until 7 PM EST this evening for INZ021-028>031- 035>049-051>057-060>065-067-068. && $$ SHORT TERM...Eckhoff LONG TERM...White AVIATION...Nield