


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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052 FXUS63 KIND 121412 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 1012 AM EDT Sat Jul 12 2025 .KEY MESSAGES... - Localized flooding and isolated strong to severe wind gusts possible this weekend - Not as warm Sunday, not as humid Sunday night...with otherwise humid and very warm/marginally hot conditions most of next week - Daily chances of showers/t-storms next week for mainly Tuesday and onward...isolated downpours/localized flooding possible && .FORECAST UPDATE... Issued at 1012 AM EDT Sat Jul 12 2025 This morning a dry, cool front is moving through central Indiana, which will allow for a brief relief from the warm and humid start to the day. However, hot and humid will still be in store for later today as SW flow returns and storm chances move in. Timing of the line of storms remains around 3 to 4pm with it`s western arrival and around 8 to 9pm for it`s eastern exit. Some showers may still linger into the overnight hours, but stronger storms should be over by around sunset. Some stronger storms could produce damaging winds and locally heavy rain as they move through. && .SHORT TERM (Today and tonight)... Issued at 246 AM EDT Sat Jul 12 2025 Early This Morning... Outflow from an old MCS was moving toward central Indiana, with brief convection still forming just behind it. Plentiful instability remains across central Indiana with temperatures still in the middle 70s to lower 80s at 06Z. Will have some PoPs in the western forecast area early this morning for this boundary as it moves into the area. Wind gusts have diminished across Illinois as the boundary moves east, so feel it will run out of steam in the western forecast area. Larger scale forcing will remain west of central Indiana early this morning and shouldn`t be a factor with this. Will keep a close eye on it though and adjust PoPs as necessary. Not expecting any severe weather given the weakening nature of the boundary. Today into Early Evening... There will be some clouds this morning around from the old convection, and the old outflow boundary will be lingering in central Indiana. Believe that convection from this boundary will have dissipated by 12Z. Will start the morning out dry, but will have some small PoPs develop as heating occurs and potentially interacts with this boundary. The primary show will be this afternoon into early evening though as a surface trough moves in from the northwest and provides broader forcing. Some upper energy will also help provide forcing. Moisture will be plentiful with precipitable water values around 2 inches. Clouds thinning this morning will allow enough sunshine to boost temperatures into the upper 80s and lower 90s for highs. This and the moisture will bring good instability to the area. However, deep layer shear isn`t good. The instability should be enough though for the threat of some damaging wind gusts with storms this afternoon into early evening though. The uncertainty of the influence of the old outflow boundary along with uncertainty in initial cloud cover makes confidence lower than desired for this forecast. Still feel though that forcing and moisture will be enough for likely category PoPs for much of the area. The highest PoPs, and the best chances for any severe storms, will be across roughly the southeast half of central Indiana. This area should be east of the initial old outflow and should see the most sunshine/highest instability. The strongest storms look to be east of central Indiana by around 00Z (8 PM EDT). Mid Evening through Overnight Tonight... Chances for showers and storms will diminish from west to east tonight as the surface boundary moves east. Will have mainly chance PoPs, lowering as the night progresses. Lows will be in the upper 60s and lower 70s. && .LONG TERM (Sunday through Friday)... Issued at 246 AM EDT Sat Jul 12 2025 Sunday through Monday... A second, less-impressive day of convection is possible Sunday as the cool frontal zone slowly progresses southward through central Indiana. While a strong storm or two cannot be ruled out, organized strong/severe storms are not expected. Greater threat will be precipitable water values in excess of 2.00 inches over southern counties combining with lift along the boundary to promote a few slow-moving late day downpours and possibly localized flooding. Overall lower instability and lackluster lapse rates are expected to thwart any severe potential, although modest/noteworthy 30KT of bulk shear could help a couple cells produce stronger gusts over southern zones. Expect a subtle drop in humidity Sunday night when light northwest surface flow drops dewpoints below 65F for several hours near/north of I-70. Rain-free conditions Sunday night will continue into early Tuesday for most locations, although a couple stray showers cannot be ruled out late Monday south of I-70. The workweek should start with humid, but non-oppressive conditions...and very warm, yet sub- 90 degree readings. Tuesday through Friday... A quasi-stationary front is expected to set-up from weak surface low pressure in the central High Plains east-northeastward into the Great Lakes. While noticeably cooler conditions will be taking place over the Upper Midwest and into southern Canada, low confidence in any taste of autumn making it into the Hoosier state during the long term period. The subtropical upper ridge will make a weak attempt to build northward from the southeastern CONUS into the Midwest, but suspect any string of 90+ degree days should be held to the Ohio Valley and south. In between these features, the CWA will see more of the very warm/marginally hot and humid pattern, with daily chances for at least diurnally-driven showers/t-storms. The location of the boundary to our north should influence location and coverage of daily convection. Overall higher precipitable water values around 2.00 inches will promote a few torrential downpours and potential isolated flooding. Low confidence due to model inconsistency in when any milder air from the north may finally make it to the local region late next week...although unlikely the period ends on a hot note. For the long term, afternoon maximum heat indices are expected to peak in the mid- to upper 90s on Tuesday through Thursday, with isolated low 100s values possible over southern Indiana. && .AVIATION (12Z TAF Issuance)... Issued at 639 AM EDT Sat Jul 12 2025 Impacts: - Scattered to numerous convection is expected this afternoon into early evening. MVFR and worse possible in convection - Wind gusts around 20kt this afternoon Discussion: VFR conditions are expected through much of the period. A surface trough will move in this afternoon and should bring scattered to numerous convection. Tried to pin down the most likely period for storms in TEMPO groups, from 19-23Z. Some wind gusts around 20kt are likely this afternoon. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...KF SHORT TERM...50 LONG TERM...AGM AVIATION...50