Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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951 FXUS63 KIND 281855 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 155 PM EST Fri Nov 28 2025 .KEY MESSAGES... - Winter Storm Warning/Advisory for much of central Indiana - Snow amounts of 4-6 inches in the Warning area, 1-4 in the Advisory - Additional snow chances Monday night into Tuesday - Wind chills in the teens at night through most of next week && .SHORT TERM (This evening through Saturday)... Issued at 155 PM EST Fri Nov 28 2025 Tonight. High clouds will begin to move in as early as the evening hours tonight ahead of the arrival of the first significant winter storm of the season. With the dry near surface conditions, expect to see temperatures quickly drop this evening before beginning to level out as the clouds move in. Overnight lows will likely end up in the low 20s which will help to prime the surface for accumulating snow Saturday morning into afternoon. There will be a weak band of snow moving northeast during the late overnight and early morning hours across the northwestern portions of central Indiana, but much of this may not reach the ground due to the very light nature, dry low levels, and the fact that the better isentropic lift doesn`t arrive until later into the morning. Saturday and Saturday Night. The main focus for the short term period will be tracking the accumulating snow threat for Saturday. Synoptically, an upper level shortwave will push southeast out of the Northern Rockies with weak southeasterly surface flow ahead of the arrival of the low. As the low nears, both surface and LLJ winds will begin to ramp up with the strongest winds aloft expected during the evening hours. The low track continues to look well to the northwest of central Indiana with the main question being the strength of the WAA and its impacts to surface temperatures and any warm nose aloft. Some of the higher resolution modeling is beginning to pick up on what we`ve been discussing over the last few days with stronger WAA in the area southeast of the low helping to bring snow ratios lower and an earlier transition to rain. The positive snow depth change among even the more aggressive models remains much more modest at 4- 6 inches which makes sense in a marginal thermodynamic situation as temperatures will hover around freezing. Travel impacts look increasingly likely during the afternoon and evening hours Saturday. Overall confidence is fairly high in the Covington to Muncie and points to the northwest area as there is good model agreement in mostly snow. Reasonable expectations for that area at this time looks to be 4-7 inches. Further south along the I-70 corridor remains the area of greatest uncertainty with a wider range of outcomes. We`re leaning towards the warmer solution with a faster changeover to rain and lower snow ratios which would put much of the area in a 1-3 or 2-4 range with the lower numbers on the southern side and higher to the north. Near Indy there will likely be a fairly stark difference between the northern and southern suburbs. Further south total snowfall of 0.5-2 inches looks reasonable, but again we are leaning towards the lower-end scenario. Much of the impacts will be over a 6-8 hour window beginning sometime in the early afternoon hours with impacts lessening towards midnight as temperatures warm. During the overnight, rain will gradually become the more predominant precipitation type, especially along and south of I-70. This will also lead to some melting of the fallen snow and may make it difficult to get accurate storm totals as folks measure in the morning. For headlines we`ve upgraded the Winter Storm Watch to a Warning across the northwest where we have the overall greatest confidence with the understanding that some of the areas may not reach the typical 5 inch snow criteria. With the holiday weekend travel and the potential for the higher end amounts. We`ve upgraded the southern extent of the Watch to an Advisory where we have lower confidence on totals with the potential that the far northern ends may get close to 5 inches, but the southern extent has a low threat. Then to the south of the original watch we have also included much of south central Indiana where we expect amounts of at least 2 inches. && .LONG TERM (Saturday night through Friday)... Issued at 155 PM EST Fri Nov 28 2025 Sunday through Friday... Overall pattern through the upcoming extended periods remains progressive with a series of systems that will bring precipitation to the Ohio Valley, along with reinforcing shots of cold air advection. This could result in additional periods where precipitation falls as snow, with some accumulations possible mainly for the Tuesday period. Sunday...Rapid departure to the surface low, quickly exiting the region to the northeast. In its wake will be strong cold air advection from northwesterly winds, still producing a tight pressure gradient and translating into a blustery day and falling temperatures from the potent 850mb thermal trough driving south. Temps will struggle once the frontal boundary arrives at the surface with generally temps in the 20s by midday and wind chill values in the teens. The deeper moisture will peel off to the northeast, but enough moisture could linger coupled with some vertical ascent to allow some flurries or light snow to be scattered across Central Indiana Sun through midday. The surface ridge will continue to slide southeast Sun evening, which will help to reduce the isallobaric gradient allowing winds to diminish with skies likely becoming mostly clear. This wills the stage for a free-fall to temperatures, and with a fresh snowfall for many locations north of Indy, expect lows to easily radiate into the single digits to lower teens. Monday into Tuesday... Monday is the benign weather day with surface ridging overhead providing a cold/dry day for Central Indiana and minimal gradient allowing winds to be light and variable. But as mentioned earlier the progressive flow to the upper level jet will quickly usher the surface ridge to the east by Mon ngt. A potent trough axis will be digging south through the plains, as surface flow starts to turn southerly across Indiana. Moistening parcels with steadily strengthening isentropic lift will present some precip type challenges early Tue morning through the day Tue. The wildcard is with how deep the trough axis slides south, which could easily shift the track of the next system further south/southeast before it congeals into a more robust synoptic system. But at the present time guidance still indicates a large precip footprint across Indiana and temps likely cool enough to have parcels present as snow/dendrites, but still possible some partial melting due to the increased isentropic ascent and easily some rain or possible freezing rain enters the setup potential. The key for how Tue unfolds and the precip type will hinge on the depth of the cold air and forcing aloft. Wednesday through Friday... The continued progressive flow to the upper level pattern remains through the end of next week, with the surface trough quickly sliding east of the region on Wed. This will result in weak ridging skirting the Ohio Valley while the 500mb pattern remains flat/zonal. The one bright spot for the second half of the upcoming week is that guidance continues to lean towards a scenario that the ridging will expand across the region. This will lead to perhaps a second dry day, although temperatures continue to be sub-seasonal but with lighter winds it will likely be more tolerable. Friday ensembles continue to demonstrate ridging pushing east and a return flow, southerly, component to winds. This will likely allow warm air advection back into the region to close the week. && .AVIATION (18Z TAF Issuance)... Issued at 1159 AM EST Fri Nov 28 2025 Impacts: -MVFR vsbys as early as 12Z, quickly becoming IFR to LIFR -MVFR cigs towards 18Z, potentially becoming IFR afterwards -Southeasterly wind gusts to 20kts Saturday afternoon Discussion: VFR conditions expected through tonight with westerly winds becoming more light and variable overnight. They will then shift more southeasterly towards mid-morning with a few gusts to 20kts through the afternoon. Snow will begin to impact vsbys as early as 12Z at LAF but more likely after 15Z with more significant impacts in the 18Z to 02Z timeframe. Cigs will also drop as the snow rates increase but there is some uncertainty as to whether they reach IFR. && .IND WATCHES/WARNINGS/ADVISORIES... Winter Storm Warning from 7 AM Saturday to 10 AM EST Sunday for INZ021-028>031-035>041-043>047. Winter Weather Advisory from 7 AM Saturday to 10 AM EST Sunday for INZ042-048-049-051>057-060>065-067. && $$ SHORT TERM...White LONG TERM...Beach AVIATION...White