


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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889 FXUS63 KIND 101348 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 948 AM EDT Sun Aug 10 2025 .KEY MESSAGES... - Hot and humid conditions today and Monday with little to no threat for rain - Daily chances for scattered thunderstorms returns Tuesday and lingers through late week - Muggy conditions last through next weekend and likely beyond && .FORECAST UPDATE... Issued at 948 AM EDT Sun Aug 10 2025 Forecast is on track this morning. The patchy ground fog has dissipated. Only a few cirrus were across central Indiana this morning. The bulk of the cirrus from convection well to the west will remain west of the area. Cumulus will pop up similar to recent days. An isolated shower or thunderstorm is not out of the question later this afternoon, but coverage would be too low to mention in the forecast. Tweaked hourly forecasts but made no significant changes. Highs around 90 with humid conditions will persist. && .SHORT TERM (Today and Tonight)... Issued at 234 AM EDT Sun Aug 10 2025 Clear skies and light winds again early this morning as central indiana resides under ridging aloft and at the surface. An area of mid and high level clouds was closing in on the northern Wabash valley as deep convection organizes from the central Plains northeast into the western Great Lakes. 06Z temperatures were in the 70s. The ongoing expansion of the aforementioned convection to our northwest which appears to be trending towards multiple clusters coalescing into a broad complex that extends from Kansas and Nebraska northeast to Lake Michigan will persist throughout the predawn hours and likely past daybreak. The ridging aloft and well defined subsidence downwind across the Ohio Valley however will not enable the frontal boundary or the convection growing in its vicinity to make much of an eastward progression through the short term. The area of mid and high clouds over northern Illinois may drift briefly into the northern Wabash Valley over the next few hours but that will likely be about it as an abundance of dry air remains overhead. Fog is not out of the question through daybreak but should remain localized and brief. With mid level heights maximized across the region...expect another hot and humid day with any convection remaining isolated at best and fully dependent on the modest instability present as MLCAPEs peak near 3000 j/kg by the afternoon despite the lingering mid level cap. If any location within the forecast area stands a chance to see a stray shower or storm...it appears to be across the southeast half of the forecast area where slightly better moisture exists. Still though...overall convective coverage will probably cap at 10% at its peak which is not enough to place in the forecast at this point. Scattered cu developing during the afternoon will diminish towards sunset with another quiet but muggy night for tonight. Temps...highs will be similar to Saturday within a couple degrees either side of 90. Lows tonight will be around 70. && .LONG TERM (Monday through Saturday)... Issued at 234 AM EDT Sun Aug 10 2025 Continued warm and humid conditions will begin the work week as ridging aloft resides across the Ohio Valley. A sluggish moving upper level trough entered across the northern Plains will help to flatten the ridge and briefly bring a lowering of mid level heights further south by Tuesday and Wednesday along with a frontal boundary that will reintroduce scattered convection into the region. The front will stall out and steadily weaken but linger across the Ohio Valley through late week with daily chances for thunderstorms persisting but slowly decreasing in coverage. The warm and humid airmass will remain with the potential for slightly warmer air to return by next weekend as the upper ridge flexes back into the region form the southwest. Monday through Thursday Night The ridging at the surface and aloft will remain the primary influence across central Indiana on Monday while keeping a frontal boundary locked in place to the northwest of the area. Model soundings show the mid level cap that has been present through the weekend will be much weaker but warmer air aloft will remain and virtually no shear will be present under the ridge. Convection will be fully reliant on the modest instability available which will limit coverage significantly but likely be sufficient to generate a few stray showers or storms during the afternoon and early evening. As the upper trough finally progresses further southeast into the region on Tuesday and Wednesday...expect a greater threat for thunderstorms with the additional influence of the frontal boundary drifting south into the region. The main convective risks will be heavy rainfall and localized flooding as a lack of substantial shear will ensure slow movement to storms that will pulse up and down in intensity. There is always the potential for a cell to strengthen enough briefly to produce localized downbursts as the cores collapse but that is likely to remain a secondary concern throughout late week. Heights aloft will begin to rise on Thursday as the upper level trough moves away into New England. Isolated to scattered convection will again be possible within the moist and unstable airmass across the Ohio Valley. Highs will be near 90 degrees both MOnday and Tuesday but the potential for increased cloud cover by Wednesday will lead to slightly cooler temps for Wednesday and Thursday primarily in the mid 80s. Friday through Saturday The ridge will expand back northeast towards the Ohio Valley into the weekend with temperatures returning to around 90 degrees for highs. The muggy airmass will remain all week and feel even more oppressive by Saturday and Sunday with the return of hotter temperatures. With dewpoints in the lower 70s...peak heat indices will likely approach 100 degrees next weekend. The return of upper level ridging and warmer air aloft will trend towards less threats for convection by next weekend with coverage likely to be isolated at best and limited to peak heating hours of the afternoon and early evening. Signs continue to increase in little to no change in the pattern for next week beyond the 7 day period into the following week as cooler and drier air remains bottled up well to the north of central Indiana. && .AVIATION (12Z TAF Issuance)... Issued at 605 AM EDT Sun Aug 10 2025 Impacts: - Brief restrictions from fog at KBMG early this morning - Fog possible at KBMG again predawn Monday Discussion: VFR conditions will continue through the forecast period. Ridging aloft and at the surface remain across the Ohio Valley with mainly clear skies and light winds expected through the morning. May see very brief impacts from fog last past 12Z at KBMG. A scattered diurnal cu field will develop for the afternoon again and a stray shower remains a possibility across the region by late day but the likelihood of a direct impact to any of the terminals is extremely low. Southwest winds will be around 10kts during the afternoon then drop back to light southerly tonight as skies clear. Fog is likely to impact KBMG again late tonight. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...50 SHORT TERM...Ryan LONG TERM...Ryan AVIATION...Ryan