Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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321 FXUS63 KIND 292008 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 308 PM EST Sat Nov 29 2025 .KEY MESSAGES... - Winter Storm Warning/Advisory for much of central Indiana - Snow amounts of 3-7 inches in the Warning area, 1-3 in the Advisory - Additional snow chances Monday night into early Tuesday, especially for south/southeast counties - Wind chills at night...into the teens through Monday night...and then possibly single digits Tuesday night through Thursday night && .SHORT TERM (This evening through Sunday)... Issued at 308 PM EST Sat Nov 29 2025 Low pressure over Missouri continues to strengthen. Snow has been spreading east through the day. However, areas along and south of I- 70 have seen little if any snow as of 3pm. ACARS soundings out of IND reveal the reason which has been very dry low-level air. This dry air has been winning the battle against falling snow all day, though that is expected to change. Radar shows a donut hole shape indicating snow aloft but none closer to the surface. This radar donut hole has been shrinking, signifying continued erosion of the low-level dry layer. A gradual wind shift from southeast to southwest will also help bring additional moisture northward, allowing snow to reach the ground more easily. Expect snow to redevelop within the next 1-3 hours. Given the late start in snowfall along and south of the I-70 corridor, amounts on the lower end of the forecast spread are now favored. High-resolution guidance is beginning to trend in this direction as well with 1 to 3 inches in recent runs. Further north, near Lafayette, amounts between 5 to 7 inches still look good. We`ve had a report of 4 inches measured as of 3pm near Kokomo. Our primary forecast challenge today will be timing the transition to rain. This depends on the strength of the low and how far into the occlusion process it gets. These factors will influence the magnitude of low to mid-level warm air advection ahead of the system and its surface cold front. All guidance shows warm air advection fully scouring away residual cold air by 00-04z, with temperatures warming into the mid 30s. Most if not all of our area will warm to above freezing during the night tonight. Some high-resolution models still hold on to near-freezing temps for the duration of the night across our north, however. A changeover to rain may substantially cut back on snow totals from I-70 southward. North of there, it may be too brief or too little too late to limit expected accumulations. Additionally, a period of drizzle or light snow flurries appears likely into the day Sunday. Model soundings are hinting at residual low stratus with sufficient forcing for at least some light precip. Whether it is drizzle or light snow will come down to cloud depth and magnitude of forcing. Some lake-induced snow showers may drift into northeastern portions of the CWA as well. Aside from snow, winds look to increase today as the surface low approaches. Southeasterly winds between 10-20kt gusting to 30kt are possible at times this afternoon into tonight. There may be a period of blowing snow before warmer temperatures cause the snow to become wetter/slushy. && .LONG TERM (Sunday night through Saturday)... Issued at 308 PM EST Sat Nov 29 2025 Extended Synoptic Overview...Predominately a cyclonic flow aloft, with a strengthening, negatively tilted upper-level trough across the Central CONUS early in the week, which will help to reinforce the slugs of cold air into the Ohio Valley, allowing for continued below-seasonal temperatures and a progressive active setup that will feature occasional shortwaves skirting the region. Sunday Night through Monday... Post frontal snow showers will erode in the evening hours, perhaps some lingering moisture in some northern locations. But overall expect quick radiational cooling to occur with overnight lows falling into the teens to perhaps the single digits in the northern forecast area. Cloud cover will be the wildcard, but it appears a minimal concern based off of current analysis. Monday night through Tuesday...Confidence continues to increase with a moderate shortwave that will be associated with or just ahead of a deep trough axis. The shortwave is progged to congeal south of central Indiana; however, it does appear a large precipitation footprint will accompany this next system and could introduce light snow to central and southern Indiana late Mon into Tue. Guidance has been consistent with the track, but some ensemble members are hinting at a northern push which could cause precip chances along with snow potential to rise. Wednesday through Thursday...The robust trough axis pivots east through the region, which will allow for reinforcing shots of strong cold air advection from the northwest. At this time guidance indicates a broad surface ridge encompassing much of the region mid- week behind the frontal passage, but the main storyline for Wed/Thur will remain with the temps expected to remain well below seasonal conditions in the 20s. Friday through Saturday...The progressive pattern will persist as guidance indicates the surface ridge departing to the east and allowing a return flow moisture setup, just as yet another deep 500mb trough axis digs into the southern plains. This feature has been consistent amongst ensemble members. If this all couples together at the right location, it is possible late in the week into early weekend another period for snow could be shaping up as the synoptic pattern could become favorable. && .AVIATION (18Z TAF Issuance)... Issued at 101 PM EST Sat Nov 29 2025 Impacts: - Deteriorating conditions through the day in snow - Visibility will go IFR first into the afternoon followed by ceilings late afternoon into the evening - Worst prolonged conditions will be at KLAF. Best overall conditions at KBMG. - Winds veering through the day with gustiness increasing Discussion: Snow has begun from HUF to IND northward. BMG has yet to see any snow and may not until later this afternoon/evening. Expect IFR conditions within snow as rates may be moderate to heavy at times. As warm air pushes northward a transition to rain is anticipated from HUF to IND southward. Rain may also mix in at times at LAF but by that point the bulk of the precipitation may be over. Timing of the transition from snow to rain is a bit tricky, but somewhere between 02-06z appears likely. Rain/snow ends by 09-12z for most with lingering drizzle and MVFR ceilings. In addition to precipitation, winds will increase to between 10-15kt this afternoon, some gusts to 20-25kt. Winds switch to southerly as surface low pressure approaches, with speeds increasing to 15-20kt gusting to 30kt. Winds become westerly after the system`s cold front passes Sunday morning with continued guests between 20-30kt. && .IND WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning until 10 AM EST Sunday for INZ021-028>031- 035>041-043>047. Winter Weather Advisory until 10 AM EST Sunday for INZ042-048- 049-051>057-060>065-067. && $$ SHORT TERM...Eckhoff LONG TERM...Beach AVIATION...Eckhoff