


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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814 FXUS63 KIND 280133 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 933 PM EDT Wed Aug 27 2025 .KEY MESSAGES... - Scattered showers Thursday over northern counties with lower chances to the south and west - Dry and quiet weather for the weekend into early next week - Potential for another system mid-week with another shot of cooler afterwards && .FORECAST UPDATE... Issued at 933 PM EDT Wed Aug 27 2025 Areas of mid level clouds were drifting across the northwest half of the forecast area this evening with mainly clear skies elsewhere. Showers over central and northern Illinois earlier had largely diminished. 01Z temperatures ranged from the upper 50s to the mid 60s. The region remains under the influence of a persistent longwave upper level trough anchored near James Bay and impacting much of the country east of the Mississippi River. A stronger wave traversing down the back side of the upper trough over the upper Midwest will approach the area from the northwest by daybreak Thursday. Models appear to be struggling a bit in handling the overall intensity of the wave aloft evidenced by the convective cluster over southern Minnesota which is more developed than most short range guidance has shown. The expectation overnight is that the ongoing activity will track southeast while gradually weakening...but will make it into northwest Indiana during the predawn hours and potentially into the northern Wabash Valley and far northern portions of the forecast area near or just after daybreak Thursday. Sped up the arrival of showers by a couple hours in northwest counties as a result and may eventually need to expand precip chances further south into the forecast area on Thursday morning. Bumped up cloud cover overnight and nudged low temperatures up a degree or two in the northern Wabash Valley. Zone and grid updates out. && .SHORT TERM (This evening through Thursday)... Issued at 205 PM EDT Wed Aug 27 2025 Rest of Today and Tonight. As of early this afternoon coverage of diurnal cu continues to increase as surface temperatures are warming into the upper 60s to low 70s with saturation at the top of the boundary layer. With the surface high centered over the southwestern counties the winds at the top of the boundary layer are much weaker than yesterday which is keeping surface winds to the 4-8 mph range. Expect diurnal cu to maximize towards 20Z with a gradual decrease afterwards and towards sunset. A weak upper level wave aloft will advect additional mid and high level clouds through the overnight hours tonight which will help to insulate temperatures more than the last few mornings with overnight lows only in the low to mid 50s. Wednesday. Thursday. The most active day of weather for the period will be tomorrow afternoon as another upper level wave pushes through the Great Lakes region with portions of central Indiana on the southwestern periphery of the better forcing aloft. Confidence continues to increase in at least some precipitation from near Lafayette east and portions to the north and east of Indianapolis with highest confidence towards Muncie. There will be at least some instability due to the steep lapse rates aloft but surface moisture will be minimal and help to limit the higher-end CAPE values. There remains some timing differences in the passage of the better forcing between the different CAMs but the early afternoon currently looks to be the most favorable time. && .LONG TERM (Thursday night through Wednesday)... Issued at 205 PM EDT Wed Aug 27 2025 Thursday Night Through Sunday. Another surge of cooler air will move in behind the exiting upper level trough with precipitation expected to be well out of the forecast area by 00Z. This surge won`t be quite as potent as the earlier weak cool air but expect most areas to fall into the low to mid 50s with gradually clearing skies. Upper level northwesterly flow and northerly surface flow will continue into the early weekend with mostly clear skies and quiet weather. Little to no flow aloft will keep a fairly persistent pattern even into early next week. Monday Through Wednesday. Surface flow will gradually become more easterly early next week as a low pressure system forms across the Upper Plains and gradually moves eastward. Confidence in the forecast lessens going towards the middle of the week as models struggle to resolve how this weak system interacts with a much stronger upper level trough moving south out of Canada but it looks likely that at least by mid to late week rain chances will begin to increase with another strong surge of cold air behind the system helping to keep temperatures below normal. && 1 .AVIATION (00Z TAF Issuance)... Issued at 625 PM EDT Wed Aug 27 2025 Impacts: - Low chance for rain/storms Thursday afternoon mainly at KIND and KLAF Discussion: VFR conditions expected through much of the forecast period. Diurnal cu will diminish this evening but an area of mid level clouds over northern Illinois will drift into the region overnight followed by additional clouds associated with convection ongoing over Minnesota. The majority of the convection will remain northeast of the terminals on Thursday but showers associated with a frontal boundary will move across the northeast half of central Indiana. An isolated rumble of thunder is not out of the question during the afternoon but overall impacts to KIND and KLAF should be minimal. Winds will be from the southwest at less than 10kts for the bulk of the forecast period. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ UPDATE...Ryan SHORT TERM...White LONG TERM...White AVIATION...Ryan