Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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613 FXUS63 KIWX 220509 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 109 AM EDT Wed May 22 2024 .KEY MESSAGES... - Potential of strong to severe thunderstorms remains for late tonight, mainly west of I-69, but confidence is decreasing. The greatest threats are damaging wind gusts. - Warm and muggy conditions to be replaced by somewhat cooler and less humid air later this week into the Memorial Day weekend with some additional chances for showers and storms. && .DISCUSSION... Issued at 223 PM EDT Tue May 21 2024 A robust cumulus field has blossomed across the area today in the warm sector south of a front that is positioned just north of the MI/IN border. A few isolated showers or storms could pop up along this front, but have only kept a slight chance for this afternoon with soundings showing a capping inversion that will limit convection. The bigger concern is the potential for severe weather late tonight. Convection is ongoing ahead of a surface low across portions of Iowa into Wisconsin. CAMs show a QLCS developing upstream with the greatest tornado potential across Iowa, but there is less confidence into the southern Great Lakes given expected tendency to some outflow dominance through time, and the fact 0-3km shear will be more marginal with eastward extent compared to upstream across the MS Valley. The main shortwave will lift up into northern Michigan, while a second wave farther south will push across central Illinois into Indiana. As these waves diverge, some of the CAMs are also showing a split in the line of storms, meaning that our forecast area is less favored for severe weather, except for maybe the northwest corner. The latest SPC Day 1 Outlook maintains a fairly sharp gradient in severe potential from Enhanced Risk far northwest to Marginal Risk across southeast which falls inline with above factors and the gradient in convective environment expected through time. Given strong DCAPEs, some concern does exist if integrity of linear convection is maintained to have some damaging wind gusts late evening/early overnight across the west/northwest. Hail looks to be a lower end threat, and focused probably extreme west/northwest. The cold front stalls just east of the area Wednesday morning, and so there could still be isolated to scattered showers and storms, but the risk of severe weather is low. Broad trough remains over the region going into Thursday, so while the better moisture and energy will be to the southeast, the is still a chance of storms in our area south of US 24. Although transitory ridging moves in on Friday, with will also bring increasing moisture up from the south and a continued chance for mainly afternoon convection. A cold front comes through Friday night with the potential for moderate to heavy rain, and then Saturday should be dry and noticeably cooler with highs in the 70s. The more moderate temperatures will persist through Memorial Day as will periods of showers and thunderstorms. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 108 AM EDT Wed May 22 2024 Have taken out all mention of shower/storm chances for KFWA and KSBN overnight. There is still a slight chance for a shower or storm, but confidence is so low on when and where these chances could occur that I felt it was better to leave them out of the TAFs completely. Southerly winds will be gusty overnight with gusts 30-35 kts possible. Dry conditions and VFR ceilings prevail into the day Wednesday. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...Small Craft Advisory until 5 AM EDT early this morning for LMZ043-046. && $$ DISCUSSION...Cobb AVIATION...Skipper