Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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063 FXUS63 KIWX 250510 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 110 AM EDT Wed Sep 25 2024 .KEY MESSAGES... * Lake effect rain showers overnight and through Wednesday. * Isolated showers are possible in the afternoon area-wide. * Seasonable temperatures and periodic chances for showers late this week through early next week. && .DISCUSSION... Issued at 205 PM EDT Tue Sep 24 2024 Scattered showers and storms remain the main focus this afternoon into early this evening. As of 18z, there is a ~1008 sfc low just now entering nw IN with a warm front extending east into nrn IN and nw OH. These sfc features will continue to lift north toward the MI border this afternoon in advance an incoming shortwave impulse. Showers/storms will accompany this system given the ongoing ample moisture transport within broad isentropic ascent preceding the shortwave. The main area of interest is still into mainly eastern portions of the FA where a muddled warm sector is building in with MLCAPE nearing 1000 j/g under 25-30 knots of effective bulk shear. SPC Marginal Risk appears reasonable in this environment with low LCL heights hinting at the low chance for an isolated weak tornado/landspout, with isolated wind damage the primary threat. The overall severe threat is limited by meager lapse rates and lacking heating thanks to cloud cover. A few showers may linger within the lingering shear axis tonight, mainly near Lake MI due to some minor lake enhancement. Kept fog and stratus in the grids otherwise overnight into early tomorrow given lingering moist low levels and light winds. The shear axis and/or trailing inverted trough does slowly slide east through the area on Wednesday. The result is a non- zero chance for a few showers/drizzle, though the strip away of moisture in the mid levels and weak forcing in between upper level systems may preclude isolated light showers from developing. Thursday is likely a dry and seasonable day before daily rain shower chances return Friday through early next week. Tropical cyclone remnants lifting north from the Gulf of Mexico look to get absorbed into a leftover closed low over the lower-mid MS Valley later Thursday through Saturday, before opening slowly northeast toward the Great Lakes region Sunday into early next week. The best opportunity for rain locally look to be Saturday and beyond, though confidence regarding track/evolution of these merging features is low. Temperatures should be pretty close to seasonal norms otherwise. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 105 AM EDT Wed Sep 25 2024 Generally stayed close to the existing TAFs for this issuance. Stratus is blossoming quickly between KSBN and KFWA and this was captured accordingly in the TAF. Fog is becoming less certain amid this rapidly developing stratus field which will likely preclude any fog development at KFWA, while a mid-level cloud deck at KSBN has most likely squashed the FG potential there. Forecast cross sections are rather soupy though the day but with decreased subsidence through time which should allow any subsidence inversion to ease late-morning. Isolated showers are anticipated (lake effect or otherwise) but indeed, coverage will be isolated. Therefore, carried on with the dry TAF for now. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Steinwedel AVIATION...Brown