Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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101 FXUS63 KIWX 091041 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 641 AM EDT Thu May 9 2024 .KEY MESSAGES... -Rain with chances for thunderstorms today. There are low chances for rain showers late tonight far west near Lake Michigan. Highs will be in the mid to upper 50s and 60s, with breezy northeasterly winds. -Cool Friday and Saturday, with highs in the upper 50s and low to mid 60s. There are chances for Showers and a few thunderstorms Saturday, but otherwise expect partly to mostly sunny skies. -Chances for showers and storms through the first portion of the work week. Highs will be in the 70s. && .DISCUSSION... Issued at 531 AM EDT Thu May 9 2024 As of this writing, a surface low was centered just south of IND, with an elongated trough extending back from the low into Minnesota. Showers and thunderstorms are just to the east of this trough, with mainly light showers extending eastward north of the low in our CWA. The lightning thus far is further west of us in the better elevated instability, however expect a downtrend (and southeastward movement) into the afternoon as the low departs and the better moisture/instability begin to wane. Increased moisture advection thanks to the nose of a weak LLJ has led radar returns over our CWA to blossom in the last hour or so, with quite a gradient in dewpoints from NE to SW in our forecast area. Near White county, IN we have dewpoints around 59 degrees. Near Hillsdale MI in the northeastern CWA, dewpoints are around 42 degrees! Expect the best rain to focus along this gradient, which will move slightly north then sink south and east with time. SPC clipped our far south and eastern CWA in the marginal risk for severe weather, but I`m skeptical given we have limited instability and wind shear (less than 30 knots of bulk effective shear and 500 J/kg of sfc based CAPE to work with)...as the better moisture/instability/proximity to the low will be just to the south of our CWA. Mid level lapse rates don`t do much for us either-with our area seeing between 5-6.5C/km. Left the thunder chances in the south and east through the day, but wouldn`t be surprised if it remained fairly limited. Highs today will only be in the 50s and low 60s, with mostly cloudy skies and strengthening east-northeast flow into the afternoon. We`ll see a lull in the precipitation this evening before additional rain showers are possible tonight along a trough axis along Lake Michigan, but probability is low given limited moisture. Dry conditions prevail for Friday with an upper level ridge and surface high in place, with highs in the 60s. Lows will be in the 40s both tonight and Friday night. A potent little shortwave will impact our area late Friday night into Saturday night, with a corresponding surface low moving from WI southeastward into our central/eastern CWA by Saturday morning, then into Ohio by the evening. Rain is likely. Scattered to isolated thunderstorms are possible too, with mid level lapse rates around 6.5 to 8C/kg, decent moisture transport in the low/mid levels, and around 500 J/kg of sfc based CAPE. Highs will be in the 60s. Sunday (possibly part of Monday) will be dry, with mostly sunny skies and highs in the upper 60s, low to mid 70s (warmest west half). It looks like we`ll see another upper low for the first part of next week, so expect daily chances for showers and storms with highs in the 70s. && .AVIATION /12Z TAFS THROUGH 12Z FRIDAY/... Issued at 631 AM EDT Thu May 9 2024 Surface low tracking eastward over the southern parts of the CWA and will bring rain showers, periods of MVFR ceilings/vsbys through the period. A thunderstorm or two will be possible this morning across the area, however after 18z Thur thunderstorms will mainly be south of both sites. Northeasterly winds today. Winds will gust at times to around 20 kts. Around 08z Friday, rain showers will come to an end and cigs will improve to VFR as the low moves eastward out of the area. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...MCD AVIATION...Andersen