Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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528 FXUS63 KIWX 081919 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 319 PM EDT Sat Jun 8 2024 .KEY MESSAGES... - Scattered showers through the evening, mainly northwest of Interstate 69. - Dry Sunday through the middle of next week. - Remaining below normal much of the period (coldest Monday) with signs still pointing towards above normal temperatures by next weekend. && .DISCUSSION... Issued at 318 PM EDT Sat Jun 8 2024 Main, albeit limited, focus of the forecast resides with chances for showers across the area as a combination of a weak low/mcv entering NW Illinois, a warm front surging NE from eastern IA to central Indiana and limited upper level dynamics approaching from the north. Small area of showers and storms has generally dissipated across N IL with the bulk of precipitation located well north of the area (E WI into NW Lower MI) as well as western KY. Returns passing across the area at the present time aren`t reaching the ground as fairly dry low level airmass remains in place. Models are fairly consistent on at least some widely scattered to scattered showers developing along the cold front, presently located in eastern IA, as it enters N IL/NW IN after 22Z. Pockets of clearing across not only our area, but locations to the west have allowed temperatures to climb well into the 70s with a few locations pushing upper 70s, not far from the convective temp. Low to mid 60 dewpoints were attempting to surge northeast, but recent obs show some mixing out of the dewpoints as the same clearing was allowing some of the slightly drier air to reach the ground. While dewpoints will increase somewhat, quality of the moisture may help limit what could be an interesting setup for some low topped stronger showers (isol thunder) with several hundred J/KG CAPE. In addition the sharp nature of the front and approaching sfc wave does increase the effective shear above 40 kts along and just ahead of the front. Last item against a bit more organized threat is upper level vort drops south into the area but impacts not will well behind the front. Went with a narrow window of likely pops prior to 00Z (mainly for collaboration) when greatest coverage may occur with a quick drop to chc thereafter. Did add a brief mention of thunder back for a few hours either side of 00Z. Some gusty winds may accompany the showers as well as immediately behind the front. Once we get by tonight, forecast rather quiet as sfc high pressure builds across the area with the ridge axis passing overhead Tuesday. Decent mixing of stronger winds above the sfc may occur late morning into the afternoon with some gusts of 25 to 30 mph possible. Below normal temperatures will dominate with the coldest day being Monday in the wake of 1 more frontal boundary Sun night. Increasing upper level heights and slowly returning southerly flow will setup Wednesday on, beginning the climb back to near and eventually above normal temperatures. Even with the increase in temps, sufficient ridging will remain in place to the south, limiting return of gulf moisture and any precip chances until maybe Thursday night, with even those chances pretty slim at this point. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 124 PM EDT Sat Jun 8 2024 Mainly VFR conditions expected through the TAF period outside of minor decrease in vsbys to MVFR cats in rain showers, especially for KSBN after 19z Sat through about 03z Sun with a cold frontal passage. A rumble or two of thunder is also possible but did not mention in TAFs with low probability of occurrence. Gusty southwest winds up to 20 knots ahead of and with cold front arrival. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Fisher AVIATION...Andersen