Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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979 FXUS63 KIND 102253 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 653 PM EDT Mon Aug 10 2026 .KEY MESSAGES... - Hot and humid through at least mid week, with daily chances for showers and storms...especially through Friday morning - Multiple rounds of severe storms will be possible from early today through at least Wed night...w/damaging winds, heavy rainfall/flash flooding the primary threats && .DISCUSSION (This evening through Monday)... Issued at 201 PM EDT Mon Aug 10 2026 Surface analysis early this afternoon shows southwest flow in place across Indiana. This was due to a weak trough of low pressure stretched from northern Michigan to IA and NRN KS and strong high pressure in place across the southeastern states. GOES19 shows scattered clouds were still found across central Indiana with more abundant cloud cover over MO and IL where light showers were present. Dew points were quite high, in the lower 70s. Aloft, water vapor shows mainly a NW flow in place. streaming from MT and WY, across the upper midwest, before slipping slightly south to the southern Great Lakes and northeastern states. A weak disturbance was found over IA, helping to trigger those light showers to the SE. Tonight...Uncertainty remains high for shower and storm chances. Forecast soundings show deep CAPE available this evening but a CAP appears to remain in place within the lower levels, limiting deep convection. Provided the CAP holds, dry weather will be expected through much of the evening across and into the overnight. Some of the forcing to the west within the NW flow aloft should propagate across northern Indiana overnight. This will be our best triggering feature tonight. Thus will try and limit pops to the northern and northeast parts of the forecast area where those dynamics are more likely to pass. Caveat and low confidence remains for isolated showers or storms late this afternoon and into the evening. The warm and humid air mass in place will result in lows in the upper 60s and lower 70s. Tuesday and Tuesday Night... Models agree with more forcing aloft within the NW flow aloft passing across Central Indiana during the afternoon and evening hours. This forcing along with the very warm and moist airmass in place will be favorable for additional shower and storm development on Tuesday afternoon. Forecast soundings show deep CAPE across the area with values over 3300 J/KG. Also PWATS will be over 2 inches. HRRR suggests an area of thunderstorms over Central Indiana during peak heating hours on Tuesday afternoon and into the evening. These storms will have the potential to be severe with strong updrafts capable of producing damaging straight line winds and heavy rainfall resulting in flooding. Confidence on precise timing and locations remain low. This will use high pops over a larger window late tomorrow and tomorrow evening. Again, westerly flow and a warm and humid air in place will allow for high temperatures in the upper 80s to around 90. Wednesday and Wednesday Night... The similar NW flow aloft will remain in place across Central Indiana and the upper midwest on Wednesday and Wednesday Night. Again, models suggest yet another wave to pass across Indiana within this flow. Some ridging pushing easting should allow the flow to become a bit more NW, which would allow for storm development and propagation to be more impactful across all of our forecast area rather than just the north. Forecast soundings on Wednesday again suggest deep CAPE aloft, over 3500 J/KG, but a cap in place once again through the middle of the afternoon. This should allow us to include dry weather through the first parts of the day, followed higher pops in the mid afternoon into the evening. Again, highs will reach the mid to upper 80s. Once again, heavy rains will be possible, but high uncertainty remains. Thursday and Friday... The upper pattern during this time is suggested to continue as NW flow aloft, but evolve to ridging building across the central Plains. Embedded waves within the flow are suggested to pass on Thursday Night, with weak ridging building across IL and the western Great Lakes. Within the lower levels a weak, warm frontal boundary looks to be lingering across Central Indiana before sagging southward to on Friday. This with a warm, humid and unstable air mass in place will be sufficient to include pops, particularly on Thursday as the best wave and lower level trough will be in place at that time. Again highs in the mid and upper 80s will be in place on Thursday, with slightly cooler values on Friday as winds take a more northeasterly component as the front sags southward. Saturday through Monday... Aloft, strong high pressure is suggested to set up over the lower Mississippi valley, with a ring of fire possible set-up impacting northern and Central Indiana. Several embedded short waves are suggested to push across Central Indiana through this time amid the west to northwest flow. Forecast soundings suggest a conditional situation, with plenty of CAPE available each day yet still a CAP suggested each day also. Thus overall, confidence remains low for showers and storms, but enough ingredients remain present to necessitate at least some mention of pops. Above normal temperatures are expected to continue this weekend. && .AVIATION (00Z TAF Issuance)... Issued at 653 PM EDT Mon Aug 10 2026 Impacts: - Convection possible through much of the period, best chances from KLAF to KIND northward. Discussion: Outside of convection, VFR conditions are expected through the period. Some low VFR ceilings are possible early near KLAF. Otherwise mainly mid and high level ceilings are expected tonight. Lower VFR ceilings will likely become predominant on Tuesday with convection around. Scattered thunderstorms will likely remain north of the TAF sites through the evening, then scattered convection will be around. However, confidence is not high enough to go anything other than VCSH at most sites. A larger area of convection is likely to move across at least the northern sites Tuesday, but specific timing is uncertain. Will use VCTS or PROB30s as needed. Severe convection is possible. && .IND WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM EDT this evening for INZ051>053-060>062- 067>070. && $$ AVIATION...50 DISCUSSION...Puma