Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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671 FXUS63 KIND 061836 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 236 PM EDT Thu Aug 6 2026 .KEY MESSAGES... - Occasion showers/t-storms today into next week. - Localized ponding/flooding of low-lying areas will be possible where repeated rounds of downpours occur - An isolated strong/severe storm cannot be ruled out. && .DISCUSSION (This evening through Thursday)... Issued at 236 PM EDT Thu Aug 6 2026 Surface analysis this morning shows a broad Bermuda high pressure system in place, providing warm, southerly gulf flow to Indiana and the Ohio Valley. Remnants of the convective cluster over MO/IL and Indiana continue to weaken and drift east with warming tops. This was providing a large mid level cloud deck across the region. Radar shows some showers still waning near the Wabash River, but some new development was noted over NE Indiana, where a bit more sun and heating was found. Aloft a broad, shallow trough was in place east of the Rockies across the northern CONUS, with an axis near the Mississippi River. Dew points across Central Indiana were in the 60s. Tonight... Although some convective development will be possible late this afternoon due to diurnal heating, cloud cover has limited this somewhat. Overall, the trend for convection overnight will be diminishing, leading to partly to mostly cloudy skies overnight. Although our area will remain mainly under the influence of the surface high pressure, another short wave of forcing should be working through the upper midwest overnight, bringing more mid cloud for late tonight and Friday. Forecast soundings show a non saturated but moist column in place over Indiana with pwats over 1.7 inches. Thus another warm and humid night will be expected with clouds in the area and dew points in the upper 60s. Friday and Friday Night... The upper pattern will persist with weak troughing remaining in place across Indiana and Illinois. Models hint at another short wave passing on Friday Night. Meanwhile, Forecast soundings again suggest a favorable situation for diurnal convection with favorable CAPE and and high pwats. HRRR suggests late afternoon and evening convection once again, thus given these favorable ingredients, pops will continue to be needed, with the best window from 21Z-01Z. There will be little change in the air mass as the surface high continues to keep mainly warm and humid southerly flow in place, resulting in highs in the middle 80s and lows in the upper 60s. Saturday and Saturday Night... Indiana will again start the day with the warm and humid airmass in place. Again, depending upon the evolution of these convective systems, convective debris could be lingering as well as any storm remnants. Another short wave is suggested to pass within the NW flow aloft on Saturday, but confidence on timing these weak systems is low. The air mass remains favorable for convection with high dewpoints and some instability in place, but much more mid level drying is in place at that time. There does appear to be some agreement toward subsidence and drying on Saturday Night in the wake of this wave, thus will trend the overall day toward dry weather late in the day and on Saturday Night. Sunday through Thursday... Little overall change in the upper pattern is expected through this period. Models suggest broad, shallow troughing in place across the northern CONUS east of the Rockies. This will lead to continued NW flow aloft with several embedded short waves poised to pass across Indiana within the flow aloft. Confidence in any of these waves is low at this time. However models do suggest a weak passing frontal boundary on Tuesday and Thursday. Given this, best chances for precip will likely be on these days. Forecast soundings through the week suggest steep lapse rates present with sufficient instability to support convection. Thus this in combination with the expected passing waves will necessitate pops in each day of the forecast. Temperatures look remain above normal given the warm and humid southerly surface flow in place. && .AVIATION (18Z TAF Issuance)... Issued at 1257 PM EDT Thu Aug 6 2026 Impacts: - Mainly VFR this afternoon - MVFR Possible overnight, toward 071200Z Discussion: GOES19 continues to show a decaying convective MCS over IL and Indiana with a mid level cloud deck across the TAF sites. Radar shows decaying showers trying to progress east near the Wabash. The decaying system is expected to continue to weaken and push across the TAF sites this afternoon, providing VFR Cigs. HRRR suggests enough clearing could be had for a pop up TSRA late this afternoon and early evening. Confidence is low for this, thus a VCTS mention will be used for now. Overnight, low dewpoint depressions and light winds will likely lead to fog and/or MVFR Stratus development around diurnal minimums. && .IND WATCHES/WARNINGS/ADVISORIES... None. && $$ AVIATION...Puma DISCUSSION...Puma