Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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280 FXUS63 KIND 302311 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 711 PM EDT Thu Jul 30 2026 .KEY MESSAGES... - Quiet weather with near normal temperatures today and tonight - Showers and thunderstorms return late on Friday and continue through the weekend. There is an excessive rainfall threat Friday night through Saturday for most of central Indiana. - Warming trend likely for the first week of August && .DISCUSSION (This evening through Thursday)... Issued at 116 PM EDT Thu Jul 30 2026 Surface high pressure has built into the region and a cool and a dry air mass is in place. Temperatures have risen into the low-mid 80s and dew points have dropped into the mid 50s in a few places. Efficient boundary layer mixing has allowed dew points to fall below guidance (as low as the 5th percentile). Additionally, high temperatures may run a few degrees above guidance. Still, near average readings are expected this afternoon. Surface high pressure along with light and variable winds may allow for patchy fog tonight like previous nights. However, increasing high cloud cover tonight may limit coverage in comparison. Fog is most probable along rivers and in rural/agricultural areas. Aloft, troughing over the northeastern US will promote northwesterly flow across the Midwest. Ensemble guidance is in good agreement showing a shortwave trough diving southeast within this flow, arriving later Friday evening. Showers and thunderstorms are possible as early as Friday night. Guidance then slows the shortwave down as western ridging amplifies. This should bring higher rain probabilities into the day Saturday, potentially into early Sunday. Locally heavy rainfall amounts are possible owing to the slow system motion. Looking into next week, the weekend shortwave departs eastward while the polar jet lifts north. Though there is no strong signal for either troughing or ridging, the jet stream residing well to our north should allow temperatures to creep upwards. A warming trend is therefore favored next week with highs potentially reaching into the upper 80s / near 90 at times. Some guidance keeps the jet stream active, with frequent storm systems embedded within the broader flow. This may act to keep daily precipitation chances above average through next week as well. However, the signal regarding precipitation is less clear than for temperatures. && .AVIATION (00Z TAF Issuance)... Issued at 711 PM EDT Thu Jul 30 2026 Impacts: - Low probability ground fog tonight Discussion: VFR conditions expected through the TAF period. Surface high pressure across the area will provide calm to light and variable winds through tonight into Friday morning, with only some slowly increasing high level cloud cover. There is a chance for patchy ground fog late tonight to near daybreak Friday, but this is too low probability for inclusion, as the increasing high clouds will work against fog development. Any fog that does occur will likely be very brief and limited to the outlying sites. Winds will become southerly around 5-9KT tomorrow, with scattered cumulus developing around 5kft and slowly increasing mid and high clouds, with ceilings dropping to around 12kft late in the period. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ AVIATION...Nield DISCUSSION...Eckhoff