Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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791 FXUS63 KIWX 061751 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 151 PM EDT Mon May 6 2024 .KEY MESSAGES... - Severe weather threat for Tuesday afternoon and evening. Damaging winds, large hail, and even a few tornadoes are possible in any severe storms that develop. Heavy rain and minor flooding is possible. - Severe weather is possible again late Wednesday afternoon into the overnight, especially south of US 30. Damaging winds, hail, and localized flooding are the primary threats. Confidence is low at this time. - Cooler with chances for showers later this week into the weekend. Highs Friday through Sunday will be in the 60s. && .DISCUSSION... Issued at 146 PM EDT Mon May 6 2024 Powerhouse upper wave over the cntrl Rockies will close off across the wrn Dakotas before spinning out through the Great Lakes Thu-Fri. Downstream warm sector will broaden north into the OH valley tomorrow and support decaying plains leftovers Tue morning. Cloud debris and potential clearing in wake of morning activity will dictate possible late day svr risk but destabilization likely hindered here and which subdues overall svr risk. Ewd pinwheeling upper low and attendant cold front will progress into wrn areas Wed evening and ewd overnight. Strong/sharp return flow ahead of this along with proximity of sfc warm frontal zone general south of US24 may pose a resultant higher risk but potential outflow spoiler remnant from dy1 further south may squelch that risk. Nevertheless high chance to low likely pops retained in more favorable periods. Thereafter cool and showery as wrn flank of elongating upper low holds back through the srn lakes, reinforced by secondary disturbances digging down across the lakes Sat and again late Sun. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 151 PM EDT Mon May 6 2024 A weak area of vorticity moves from the lower Mississippi Valley into the Mid Atlantic Coast during this TAF period at the same time that a surface high pressure system moves northeast into eastern Canada. This sets the area up for winds out of the east ahead of a warm front that attempts to move through Tuesday morning. A low level inversion has formed below 850 mb and this allowed for times of MVFR CIGs this morning as the inversion traps residual moisture from recent rainfall and moisture from Lake Erie underneath it. The diurnal trends this morning also helped CIGs rise above MVFR so will keep that out of the afternoon TAFs. It`ll take until moisture rises northward with the stronger moisture stream Tuesday morning just behind the warm front. This also brings additional opportunities for MVFR CIGs, and perhaps IFR, Tuesday morning and there could be some showers or perhaps some thunderstorms with the morning batch, but the instability appears to be weaker. The NAM and even the ECMWF do show increasing instability during the midday and afternoon hours allowing for an opportunity for thunderstorms that could be strong during the afternoon time, but that`s beyond this TAF period. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...T AVIATION...Roller