


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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015 FXUS63 KIND 152340 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 740 PM EDT Tue Jul 15 2025 .KEY MESSAGES... - Seasonably warm and quite humid much of the next week, with daily chances for showers and storms - Heavy rainfall and localized flooding are primary concerns, though some potential for more organized/stronger storms will exist late Wednesday through Thursday && .SHORT TERM (This evening through Wednesday)... Issued at 217 PM EDT Tue Jul 15 2025 Presence of a warm front and weak upper wave have sparked scattered to numerous showers and storms this afternoon, and these will persist into the evening hours. Anticipate some weakening/dissipation of this activity early in the night with the loss of diurnal heating, though the arrival of another impulse within the disorganized upper wave may spark more activity later tonight, which will necessitate PoPs throughout the night. Primary threats with the activity today into tonight will be, beyond the obvious lightning, continued concerns with respect to heavy downpours and localized flooding given slow storm motion, extremely high precipitable water values in excess of 2 inches/near climatological maximum, deep pseudotropical moisture profiles, and highly efficient rain processes. These concerns will remain into Wednesday as well, though increased instability may also present an isolated/conditional wind threat late in the day Wednesday into Wednesday evening. Temperatures will remain roughly near or just slightly above persistence tonight into Wednesday given dewpoints remaining in the low 70s overnight and only slight low level thickness increases Wednesday. && .LONG TERM (Wednesday night through Tuesday)... Issued at 217 PM EDT Tue Jul 15 2025 A typical, if quite anomalously moist, midsummer pattern, will persist throughout the long term period, dominated by a broad subtropical ridge to our south and primarily subtle upper level impulses passing periodically to our north within the quasizonal belt of prevailing westerlies. Presence of a frontal boundary in the region Thursday may promote slightly higher but still low potential for organized convection during this time frame, but uncertainty is quite high given dependence upon prior rounds of storms, which will continue with time throughout the long term. Daily thunderstorm chances will be necessary, with limited predictability in any one period given mesoscale dependencies which are poorly resolved by global model guidance on the time scale of days. That said, we are moving into the heart of the ridge rider season, so one or more opportunities for strong storms producing wind cannot be disregarded, particularly given the persistence of the warm and very humid airmass. Regardless of any strong to severe storm threat that may exist on any particular day, prime conditions for heavy rain and localized flooding will persist throughout the period. With the exception of very slightly cooler temps on Friday in the wake of the weakening boundary, highs will be seasonably warm in the mid 80s to around 90, and lows in the 60s to low 70s. The humid airmass will push afternoon heat index values well into the 90s most days with a few days likely rising into the low 100s in some spots. && .AVIATION (00Z TAF Issuance)... Issued at 738 PM EDT Tue Jul 15 2025 Impacts: - Scattered showers and storms possible, mainly late tonight through midday Wednesday - Light MVFR fog possible at the outlying sites late tonight Discussion: Primarily VFR conditions expected through the period outside of any convection. Showers or storms will be possible much of the period, but particularly near BMG late tonight into Wednesday morning. Will carry a mention at BMG along with HUF and IND as sufficient forcing from a passing wave supports scattered convection. Confidence is too low for an explicit mention near LAF. The main timing for precipitation appears to be from 08-15Z Wednesday, but cannot rule out storms outside of this window. Brief MVFR ceilings are also possible from 08-14Z. Winds will be south- southeasterly to start the period and become southwesterly after daybreak Wednesday. Expect speeds generally below 10KT. The very humid airmass may promote fog development late tonight at the outlying sites, though guidance is uncertain with respect to this. Will carry some MVFR fog after about 08Z through just after sunrise for only LAF as showers or storms may help prevent fog at the other sites late tonight. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ SHORT TERM...Nield LONG TERM...Nield AVIATION...Melo