Area Forecast Discussion
Issued by NWS Northern Indiana
Issued by NWS Northern Indiana
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497 FXUS63 KIWX 031709 AFDIWX Area Forecast Discussion National Weather Service Northern Indiana 109 PM EDT Mon Jun 3 2024 .KEY MESSAGES... - Primarily dry today with highs in the 80s. A low chance of isolated storms tonight. - Widespread showers and storms Tuesday night through Wednesday. - Remaining warm through Wednesday before cooler air settles in for the rest of the week. && .DISCUSSION... Issued at 319 AM EDT Mon Jun 3 2024 Fog has developed this morning, primarily north of US 30 and is dense in spots toward the Michigan line. This as high pressure is established over Indiana with ample soil moisture from Saturday and Saturday night`s rainfall. Since the calendar reads, "June", this fog should mix out rather quickly after sunrise. Aloft, a ridge axis is noted over Illinois and Indiana on water vapor. To the west, thunderstorms are decaying as they approach Iowa early this morning associated with an area of low pressure over southern South Dakota. This low lifts northeast through the day as weak troughing over the Northern Plains encounters the aformentioned ridge. HREF guidance indicated 500mb flow not only lifts northeast but weakens through the day. 850-mb flow behaves similarly. Not much to speak of at the surface for a forcing mechanism either. Overall, a very poor case for showers and thunderstorms late today and into the overnight. As a result, leaning on high-resolution guidance, I`ve restored the dry forecast during the day and significantly limited the scope of POPs for tonight, favoring POPs for the Benton Harbor and South Bend areas. This is a significant about-face when compared to earlier forecasts; a byproduct of weak flow and drifting convection. Turning to Tuesday, a pair of short waves ripple into the area working to break down the ridge whose axis is not over the Appalachians. Tuesday likely begins dry (see preceding paragraph) but as afternoon temperatures rise well into the 80s, showers and thunderstorms will dot the area. Instability will be sufficient while shear and lapse rates are lacking. Thus, pulse, non-severe thunderstorms are favored. Showers and thunderstorms become more widespread by Wednesday morning as a deep trough aloft and cold front arrive. Strong cold air advection is in place from Wednesday night through the end of the week. This keeps high temperatures in the low-to-mid 70s. (the in-house blend is still running warm with a 75th percentile forecast Wednesday through Friday.) This trough aloft becomes cut off from the jet stream focused across northern Canada, leaving it to swirl over our heads for an undetermined length of time. Until it kicks east, expect a chance of scattered showers day-to-day and below- normal temperatures. && .AVIATION /18Z TAFS THROUGH 18Z TUESDAY/... Issued at 103 PM EDT Mon Jun 3 2024 Limited moisture at and under the base of a strong subsidence inversion has allowed a scattered to occasional low cloud/MVFR ceiling at FWA near 030. The clouds will mix out later today with VFR conditions prevailing. A weak pressure gradient is expected to support south winds under 10 knots through the period. && .IWX WATCHES/WARNINGS/ADVISORIES... IN...None. OH...None. MI...None. MARINE...None. && $$ DISCUSSION...Brown AVIATION...Skipper