Area Forecast Discussion
Issued by NWS Northern Indiana

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000 FXUS63 KIWX 220751 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 351 AM EDT Sun Oct 22 2017 .SYNOPSIS... Issued at 350 AM EDT Sun Oct 22 2017 Another unseasonably warm day is expected today with highs into the 70s. Chances for rain will increase west of Interstate 69 later today into tonight along a frontal boundary. Rain will likely engulf the entire forecast area Monday into Monday evening as low pressure develops into the Great Lakes region. Rainfall amounts between 1 and 3 inches will be possible in northeast Indiana, northwest Ohio, and south-central Lower Michigan. Much cooler and showery weather is expected behind this system into Tuesday and Wednesday, with highs on Wednesday likely struggling to get out of the 40s. && .SHORT TERM...(Today and Tonight) Issued at 350 AM EDT Sun Oct 22 2017 Mild and somewhat brisk southwest flow will yield another unusually warm late October day with highs once again well into the 70s. Clouds and chances for rain will increase into nw IN/sw Lower MI later today into this evening, and toward the I-69 corridor tonight, as a frontal boundary and associated deep moisture plume slows east into the local area. These features exist on the leading edge of a deep central US upper trough. Energy within the trough will split with southern piece toward the Lower MS Valley and northern stream jet energy northeast through the Northern Great Lakes and Ontario. The result will be a weakening/slowing trend to the aforementioned frontal circulation once it reaches our area. With that said, at least light rain should accompany the front by tonight into areas mainly west of I-69 given ample moisture, weak height falls, and right entrance upper jet associated with the northern stream energy. && .LONG TERM...(Monday through Saturday) Issued at 350 AM EDT Sun Oct 22 2017 A pattern change to a much more active/wet/cooler regime the story next week/weekend... A powerhouse Northeast Pacific jet will eventually help to carve out a rather impressive negative height anomaly over the Eastern US by Tuesday and Wednesday. Phase of this jet energy with leftover southern stream wave, a coupled jet structure, and surge of gulf moisture should allow a deepening sfc cyclone to track northeast along frontal boundary Monday into Monday night in this transition. Favor the stronger/farther west/wetter solutions of ECMWF/GEM/UKMET over the GFS/NAM at this time resulting in a bump to QPF/PoPS...especially across ne IN/sc Lower MI/nw OH near deformation pivot. Rainfall totals in the 1-3 inch range appear possible here. Strong cold advection wing wraps in under low pressure on Tuesday with breezy/sharply colder conditions. Should also see scattered to numerous rain showers given expected lake enhancement and moist cyclonic flow within deep trough axis. Additional trailing shortwave energy into the upper trough may support additional lake enhanced shower activity into Wednesday. High temperatures on Wednesday are not expected to get out of the 40s in most locations (10-15 degrees below normal). Fair wx and brief warming is expected into Thursday and possibly Friday as shortwave ridging works through in between systems. The next upper trough is modeled to amplify into the Central US by later Friday and next weekend. Models differ on timing of a strengthening baroclinic zone on the leading edge. Covered with broadbrush chance PoPs for rain and cooling temps for now. && .AVIATION...(For the 06Z TAFS through 06Z Sunday Night) Issued at 138 AM EDT Sun Oct 22 2017 VFR conditions expected through 00Z at both sites with cigs slowly lowering this afternoon, mainly at KSBN. Some concerns still linger for low level wind shear overnight at both locations before mixing of stronger winds to the surface takes place. Widely scattered showers may move into KSBN late this afternoon,with no impacts expected. Better chances exist after 00Z for steady, light rain to impact the site. Confidence low at this point on eastward extent, intensity and full impacts given it may be in a weakening state. Have went MVFR cigs/vsby starting at 2Z for now. At KFWA, rain may not make it, if at all, until outside the current period with maybe a few showers at best towards the end of the period. For now, no addition of precip or flight impacts. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...NONE. MI...NONE. OH...NONE. LM...NONE. && $$ SYNOPSIS...Steinwedel SHORT TERM...Steinwedel LONG TERM...Steinwedel AVIATION...Fisher Visit us at Follow us on Facebook...Twitter...and YouTube at: is the U.S. government's official web portal to all federal, state and local government web resources and services.