Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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816 FXUS63 KIWX 061747 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 147 PM EDT Sat Jul 6 2024 .KEY MESSAGES... - Cool and less humid today, but more seasonable for Sunday. Mostly dry weather is in place for the weekend. - More seasonable temperatures are in store for the bulk of the work week, but the warmest highs are forecast for Monday with 90 degrees possible for areas south of US-24. - Chances for showers and thunderstorms return for later Monday through Tuesday. && .DISCUSSION... Issued at 259 AM EDT Sat Jul 6 2024 Much cooler and drier air moves in behind Friday`s cold front and that helps to reduce humidity back to more comfortable levels with dew points in the 60s. However, with the jet stream still draped across the lower Great Lakes, various maximums of vorticity traverse the southern tear drop of Lake Michigan and provide opportunities for weak lift and convergence, and when paired with small areas of moisture and cooler low level temperatures, sprinkles could result. This likely occurs along and west of US-31 and south of the Toll Road today, but generally north of Winamac. There may be a period between late morning and some time this afternoon where it wanes, but there is some confidence in another period of sprinkles later this afternoon into the early evening just south of the aforementioned area. Areas farther east are removed from the better convergence and temperatures in the low to mid levels are slightly warmer and so they are expected to be drier. In accordance with the cooler temperatures in the atmosphere, surface temperatures will struggle to exceed 80 degrees today. Saturday evening, high pressure nudges in, and then escapes the area Sunday night. As such, expect a dry Sunday. Some lighter warm advection comes in during the afternoon Sunday and that will help high temperatures return to seasonable temperatures, in the 80s. Then, between Sunday night and Monday afternoon, a mid level trough edges closer to the region from the Northern Plains making it more possible for dying thunderstorms, likely just in the form of showers, to traverse the Lake MI-adjacent counties. Will continue to carry times of slight PoPs during this period. Dew points are expected to increase back into the 60s and a few areas of 70 degree dew points will also be possible as a better connection to the Gulf of Mexico becomes established on Monday. Increased low level theta-e will also contribute to near-90s high temperatures. With the trough now in a favorable position to provide increased precipitation Monday evening/night in a similar setup to a predecessor rain event (PRE) out ahead of a boundary moving through, have allowed for chance PoPs later Monday through Tuesday. Any precipitation that does form will have the opportunity to become heavy with some instability to tap into and with how moist the low levels are. 850 mb Tds surpass 10C and sfc dew points will at least be in the mid to upper 60s. The aforementioned boundary may stall in the vicinity of US-24 Tuesday night/Wednesday providing areas north of there with drier weather, but cannot totally rule out some chance for precip south of there. Models have some uncertainty moving forward with how quickly the trough can pick and throw the remnants of Beryl to the eastern seaboard between Wednesday and the end of the week. However, still have some confidence in at least a slight chance for afternoon pop up showers/storms Wednesday afternoon and Thursday afternoons. Highs are expected to be right around seasonable during this time period. && .AVIATION /18Z TAFS THROUGH 18Z SUNDAY/... Issued at 138 PM EDT Sat Jul 6 2024 High pressure building into the area with weak subsidence and somewhat drier air was helping to clear out the lower clouds through midday. Both SBN and FWA have improved to VFR. A somewhat diffuse lake shadow was moving southeast into the SBN area and was helping to clear out the clouds there. Skies should continue to clear this afternoon with conditions staying VFR into Sunday morning. Some patchy ground fog is possible by daybreak, but is not expected to be operationally significant and therefore was not included in the TAFs. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Roller AVIATION...Skipper