Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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650 FXUS63 KIWX 041842 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 242 PM EDT Thu Jul 4 2024 .KEY MESSAGES... - Chances for showers and thunderstorms persist into Friday, with locally heavy rain the main concern. - More comfortable humidity levels this weekend, with only limited chances for showers Saturday. - Somewhat better shower and thunderstorm chances return Monday into Tuesday. && .DISCUSSION... Issued at 238 PM EDT Thu Jul 4 2024 While high confidence exists on a relatively active pattern, finer details continue to have much lower confidence due to difficulty in timing and location of key features. Forecast emphasis will be on the next couple of days with few overall changes expected for the later periods. Diffuse frontal boundary was located from southern IL to north of IND and then towards NW Ohio. Area of light to occasionally moderate rainfall worked north across much of the area, but a slow weakening trend occurred as it moves away from the front and best LLJ position. Heavier rain and thunderstorms remained south of the area across central/southern Indiana associated with a weak disturbance. Although earlier CAMs suggested a bit more robust development possible late this afternoon into early evening, they seem to have backed off, maybe as a result of the more extensive coverage of the precip the first part of the day. MCV was working into southern IL and will continue east, likely being the main focus for additional development later today south of our area. With the front in the area and pockets of heating, mainly SE, can`t rule out some additional showers/storms popping that would produce mainly locally heavy rain. Pockets of clearing upstream across central IL are allowing for some new shower development. Models seem to suggest after 3Z little or no chance for development until maybe closer to Fri morning as the main trough begins to edge in to western areas. Pops also adjusted accordingly with any likely mention overnight removed. Lift from the front and plenty of moisture around should allow for isolated to maybe scattered showers/storms through late Friday afternoon along and ahead of the front. Shear parameters aren`t bad as is some cooler air aloft. However, better severe chances should remain east of the area. Bulk of the weekend could end up dry with maybe just a few light showers Saturday as the main trough pushes NE and heights increase somewhat before the next trough early next week. Some models show a weak disturbance Saturday that could still bring a few showers, but CAMs don`t seem overly impressed at this point. Typical early July temps can be expected with highs in the low to mid 60s with dewpoints remaining in the mid to upper 50s, making for a comfortable holiday weekend. Next deeper trough edges toward the region late Monday into Tuesday with chances for showers and storms increasing with this feature. Moisture return will occur ahead of the trough, but conservative chc pops will be maintained at this point. && .AVIATION /18Z TAFS THROUGH 18Z FRIDAY/... Issued at 200 PM EDT Thu Jul 4 2024 Area of showers and storms will continue to decay through mid- late afternoon with the heavier showers through 21Z expected east of the terminals across Ohio. A remnant convectively enhanced short wave across northwest Indiana could be a trigger for additional scattered showers/isolated thunderstorms late afternoon into evening, but this potential appears to maximized south and southeast of KFWA. Will carry TEMPO SHRA mention at KFWA this evening, with greater potential of thunder south of KFWA given strong instability gradient across central Indiana. Showers should diminish late evening. Another more significant short wave trough will approach the western Great Lakes toward the end of this period. A band of rain showers may affect the terminals from west to east in 12Z-18Z time period on Friday, with isolated to scattered showers and thunderstorms possible on Friday afternoon as cold front approaches. Confidence is low on thunder coverage Friday afternoon however, as frontal convergence appears to be rather weak. Mainly VFR conditions are expected this period, but a brief period of MVFR cigs is possible Friday morning. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Fisher AVIATION...Marsili