


Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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168 FXUS63 KIND 231355 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 955 AM EDT Mon Jun 23 2025 .KEY MESSAGES... - Heat Advisory in effect through Friday - Heat indices of 100-105 degrees and low temperatures near or above 75 degrees each day through Friday - Isolated to scattered thunderstorms at times mid-week onward && .FORECAST UPDATE... Issued at 953 AM EDT Mon Jun 23 2025 Following a few minor visibility reductions earlier this morning from patchy fog fueled by dewpoints in the low to mid-70s... conditions are continuing to evolve as expected with already widespread low 80s reached by 900 AM EDT, and now 84F at Indianapolis (today`s normal high) as of 940 AM. Hot and humid will be the rule today, with readings likely a degree or two higher than yesterday for most locations. Southwest winds around 10 mph this afternoon will maintain dewpoints in the low 70s for most locales. Widespread low 90s are expected by 17Z...with maximums likely in the 93-95F range for most locations this afternoon. Corresponding heat indices (already in the mid-80s to around 90 degrees at 900 AM this morning) will climb to around 100 degrees early this afternoon, peaking in the low 100s for most spots this afternoon. Afternoon cumulus may include a rogue rain shower later this afternoon south of the I-70 corridor, yet confidence too low to include in any grids. *Heat Advisory remains in effect*...drink plenty of fluids, stay in air-conditioning when possible, limit time outside and stay out of the sun...and check up on relatives and neighbors. && .SHORT TERM (Today and tonight)... Issued at 222 AM EDT Mon Jun 23 2025 Surface analysis early this morning continues to show strong high pressure over the SE states and the Atlantic off the coast of the Carolinas. This was resulting in hot and humid conditions across Indiana and much of our region amid southerly flow. GOES16 shows clear skies across the state and much of the region. Aloft, water vapor shows strong subsidence across Indiana and the Ohio Valley. A large upper level high was found over the eastern half of the United States, with a ridge axis that extended north into Ontario. This continued to keep any forcing dynamics steered well north of Indiana. Dew points remained very high across Central Indiana, in the upper 60s and lower 70s. Today and Tonight... Models suggest little overall change in the forecast. Our weather will continue to be dominated the strong high pressure systems today and tonight as we have seen over the past few days. Forecast soundings again today show a dry column, however a few isolated CU may be eked out late this afternoon. HRRR does try to imply some very isolated convection development near the Ohio River, however none of that appears close to our area and confidence for it to occur with the strong subsidence in place is quite low anyways. Thus another mostly sunny day and mostly clear night is expected, with hot and humid conditions. Temperatures today should easily reach the mid 90s again. High humidity is expected with dew points still in the 70s. This will result in WBGTRisk levels in the high category. Thus the ongoing heat advisory will remain valid as a week typical hot summer weather starts in Central Indiana. && .LONG TERM (Tuesday through Sunday)... Issued at 222 AM EDT Mon Jun 23 2025 ...HOT and HUMID SUMMER WEEK AHEAD... Tuesday through Friday... Models suggest little overall change in the weather pattern through the work week. The previously mentioned strong ridging aloft will remain in place, but slowly weaken as the week progresses, leading to continued subsidence and little change in the overall weather pattern. Forcing dynamics will remained focused across Canada and the Great Lakes, as Indiana will be protected by the ridging. Meanwhile at the surface, high pressure remains anchored southeast of Indiana, resulting in continued warm and humid southerly flow. This will keep the current air mass in place across Central Indiana, resulting in continued highs in the 90s through the week with high humidity. HRRR and a few of the models suggest afternoon convection development each afternoon from Tuesday through Friday. With little in the way of forcing dynamics present confidence is low. At the moment forecast soundings suggest a few hours each afternoon where enough CAPE and instability will be present for a shower/storm, but 700MB temps are near 10C, which tends to cap the environment. Thus for now, will expect the NBM to include to chance pops each of these afternoons for diurnal convection, but overall confidence remains low. Saturday and Sunday... A change in our weather pattern looks to begin on Saturday and Sunday, but not a big change in our weather. Models suggest the strong upper ridging in place currently will break down, allowing a more southerly flow of the steering flow aloft. Several short waves are suggested to stream across the southern Great Lakes with a possible cold front passage arriving in Central Indiana on Monday. Although the ridging aloft may be gone this weekend, the warm and humid southerly flow within the lower levels will remain in place as a boundary is suggested to set-up along the southern Great Lakes. With this warm and humid air mass still in place, our temperatures and weather will remain similar, with more highs in the 90s along with afternoon diurnal shower and storm chances. && .AVIATION (12Z TAF Issuance)... Issued at 608 AM EDT Mon Jun 23 2025 Impacts: - None; VFR Continues. Discussion: Little to no change from the ongoing forecast. Indiana will continue to remain under the influence of strong high pressure settled over the southeastern states. Forecast soundings continue to show a dry and warm column through the period. A few isolated CU will be possible this afternoon. && .IND WATCHES/WARNINGS/ADVISORIES... Heat Advisory until 8 PM EDT Friday for INZ021-028>031-035>049- 051>057-060>065-067>072. && $$ UPDATE...AGM SHORT TERM...Puma LONG TERM...Puma AVIATION...Puma