Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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280 FXUS63 KIWX 020725 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 325 AM EDT Sun Jun 2 2024 .KEY MESSAGES... - Drying out Sunday with slowly decreasing clouds. - Frequent chances of showers and thunderstorms beginning Monday night. - After a warm start to the week, it will be notably cooler by week`s end. && .DISCUSSION... Issued at 307 AM EDT Sun Jun 2 2024 A weak cold front is working its way through Michiana early this morning. This feature is most visible on radar as a fine line of showers. Behind this, dew points are falling to the 50s paired with a northerly wind. This feature is forecast to track southeast, likely washing out by the afternoon as ridging resumes aloft. Otherwise, showers are departing northwest Ohio at this time thus promising a mainly dry Sunday for the area. I say "mainly" not only for the aformentioned fine line of showers, but because we`ve noted intermittent drizzle at the office. This patchy drizzle is forecast to end in the wake of the cold front. Lastly, fog is noted in upstream observations, primarily across the Mississippi River. This airmass arrives overhead tonight such that fog could be a concern. Guidance is split at this moment, so, will pass this concern to the incoming shift. Dry weather prevails through the day Monday, amid weak zonal flow aloft and high pressure arriving in the wake of Saturday`s rain- maker. Over the Northern Plains on Monday, thunderstorms are forecast to develop in the vicinity of a cold front. These storms drift east into Illinois late in the day. This change in timing, thanks to lingering high pressure and weak flow aloft, has allowed me to remove POPs Monday afternoon. The chance for showers and storms remains in the forecast after sunset, however, but coverage is questionable. WFO Chicago and I worked to reduce POPs during that time frame. Convection amid weak zonal flow offers low confidence in the coverage of showers and storms Tuesday. In the meantime, I held close to the inherited forecast which follows a subtle diurnal curve in POP coverage. Following this, a deep cut-off low plagues the forecast Wednesday through the end of the week. This will bring widespread showers and thunderstorms Wednesday, followed by cooler temperatures. As spokes of vorticity revolve around the low in the days that follow, off and on showers are nearly guaranteed. Coverage is uncertain here as well, thus POPs near 20% litter the late-week forecast. Observed high temperatures from Monday and Tuesday in the 80s will give way to highs in the low-70s both Friday and Saturday. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 125 AM EDT Sun Jun 2 2024 Weak low pressure system is currently moving across the area and will continue to support IFR/LIFR conditions through the early morning. Latest guidance...supported by upstream obs...indicates potential for LIFR ceilings and visibilities at KSBN in the 09-14Z window as winds veer northwesterly and advect very moist conditions currently over Lake MI into the area. Dense fog appears unlikely but many upstream obs show 1SM BR and 200ft ceilings. Higher moisture content is unlikely to reach KFWA before diurnal heating kicks in but ceilings will remain IFR and could drop to 400ft at times through the early morning. Conditions slowly improve by the afternoon with VFR expected after 18Z. Confidence in exact timing of transitions to MVFR and VFR remains low however. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Brown AVIATION...AGD