Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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350 FXUS63 KIND 171901 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 301 PM EDT Tue Sep 17 2024 .KEY MESSAGES... - Mostly sunny with RH values dropping to around 20-30% this afternoon and again on Wednesday. - Hot and dry weather through Friday. - Not as warm and rain chances starting Sunday. && .SHORT TERM (This evening through Wednesday)... Issued at 300 PM EDT Tue Sep 17 2024 Satellite imagery shows high cloud cover spreading westward into Indiana, associated with a low pressure system located over the southern Appalachians. High clouds are expected to remain present through the night, though little in the way of additional westward propagation is likely. Otherwise, mid-level ridging along with surface high pressure remain the determining factors for our weather. Generally clear skies, light winds, and low humidity should allow good radiational cooling tonight. Some ground fog is possible by morning, but a mainly dry atmosphere will prevent this from becoming widespread. Tomorrow should shape up to be quite similar to today, albeit with a slight increase in low-level moisture from increased easterly flow. This may lead to greater coverage of diurnal cumulus during the afternoon hours. While moisture is a bit higher, RH values should still dip into the upper 20s or lower 30s (percent). Light winds should limit fire weather concerns for the most part. && .LONG TERM (Wednesday night through Tuesday)... Issued at 300 PM EDT Tue Sep 17 2024 There is some hope that central Indiana could receive some rainfall starting late this weekend as an upper system and an associated frontal system approaches from the west while the persistent ridge weakens and moves to the east. That said, confidence is not high on timing and coverage as the models diverge with the strength and timing of the upstream disturbance and related fronts. This is evident in LREF 500 millibar clustering late weekend into next week displayed through DESI. DESI total rainfall probability of more than a half an inch of total rain through Tuesday is currently 20-30 percent. However, with such low confidence in timing and coverage, could see this probability changing quite a bit as we get closer to the weekend. Prior to Sunday, look for the ridge to continue to result in broad subsidence and combine with a mostly dry column per Hi-Res soundings to result in continued very warm and dry weather. && .AVIATION (18Z TAF Issuance)... Issued at 139 PM EDT Tue Sep 17 2024 Impacts: - None. Discussion: VFR conditions are expected through the period. High clouds advancing westward into Indiana this afternoon should persist through tonight, most prominent from IND eastward. Some diurnal cumulus is possible but no ceilings are anticipated. Winds are likely to go light and variable overnight, perhaps calm at times. After sunrise, speeds should pick up a bit (but remain under 10kt) out of the east-northeast. Low-probability of ground fog by morning, mainly LAF, HUF, and BMG. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ SHORT TERM...Eckhoff LONG TERM...MK AVIATION...Eckhoff