Area Forecast Discussion
Issued by NWS Indianapolis, IN
Issued by NWS Indianapolis, IN
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823 FXUS63 KIND 171739 AFDIND Area Forecast Discussion National Weather Service Indianapolis IN 139 PM EDT Tue Sep 17 2024 .KEY MESSAGES... - Mostly sunny and hot today with RH values dropping to around 20-30% this afternoon. - More Hot and dry weather through Friday. - Cooler but still dry Saturday and Sunday. - Rain chances Monday? && .FORECAST UPDATE... Issued at 941 AM EDT Tue Sep 17 2024 No changes needed to the forecast this morning. Generally quiet weather is expected today with some high clouds advancing westward into Indiana from Ohio. Today should end up slightly drier than yesterday with RH values down into the low to mid 20s (percent). && .SHORT TERM (Today and tonight)... Issued at 226 AM EDT Tue Sep 17 2024 Expect dry conditions to continue across central IN as surface high pressure remains the dominant weather feature. A remnant tropical low currently over the eastern Carolinas may bring some mid-high clouds to far eastern portions of the area which could slightly limit high temperatures. The rest of the area should remain above normal in the mid-upper 80s due to strong daytime heating. Forecast soundings suggest deep mixing is likely once again during the afternoon under favorable conditions. Look for dewpoints to drop significantly later today which raises fire weather concerns. See the Fire Weather section for more details on this. Blended model guidance tends to do poorly in forecasting Td/RH on days with strong diurnal mixing. For this reason, hi-res models were incorporated to better represent the environment. Optimal radiational cooling conditions should allow temperatures to quickly drop overnight. Expect slightly below normal lows generally in the mid-upper 50s. && .LONG TERM (Wednesday through Monday)... Issued at 226 AM EDT Tue Sep 17 2024 Wednesday through Friday - Continued dry and hot weather will be expected to end the work week. The upper pattern is expected to continue to reflect a strong upper ridge from the southern plains to the western Great Lakes slowly building across Indiana through Friday. This will result in the continued subsidence and drying across the area. Meanwhile at the surface, strong high pressure is set to settle from the eastern Great Lakes, through the Ohio Valley to the deep south. Continued dry easterly lower level flow will result in little change in the overall air mass. This will result in continued above normal temperatures with highs in the middle and upper 80s and lows in the lower 60s. Saturday and Sunday - Models suggest that by Saturday and Sunday the upper ridge axis drifts a bit east of Indiana and some weak forcing dynamics try to push across Central Indiana. Mid levels begin to show signs of saturation, however the lower levels look to remain quite dry. Thus this should result in a bit of cloud cover over the weekend. This will have the impact of cooler temperatures and highs are expected to retreat to the low and middle 80s. Monday - Models suggest uncertainty with the timing of the departure of the strong ridging aloft. One solution suggests a trough pushing across the upper Midwest and Indiana, while the others show a slower departure of the ridging aloft. The quicker solution may require some pops for Monday, but uncertainty remains highs. For now will include some lower chance pops, but will expect changes in this as confidence builds. && .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. && .FIRE WEATHER... Issued at 226 AM EDT Tue Sep 17 2024 Strong diurnal mixing and a dry airmass over the region suggest MinRH values will fall to around 20-30% this afternoon with fuel moisture dropping below 8%. However, winds are only expected to peak around 5 to 10 knots. So while there is a concern for fires to pop up given the dry conditions, wildfire spread is not a huge concern due to light winds. Some municipalities in central Indiana have activated a burn ban. Please exercise caution if burning today. && .IND WATCHES/WARNINGS/ADVISORIES...None. && $$ UPDATE...Eckhoff SHORT TERM...Melo LONG TERM...Puma AVIATION...Eckhoff FIRE WEATHER...Melo