Area Forecast Discussion
Issued by NWS Duluth, MN
Issued by NWS Duluth, MN
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156 FXUS63 KDLH 260008 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 708 PM CDT Sat May 25 2024 .KEY MESSAGES... - Rain showers and thunderstorms this afternoon. Storms are not expected to be severe, but there could be a few strong storms this afternoon into this evening. - Storms weaken late this evening and rain lingers overnight over a narrow band. - Active weather continues through early next week with rain and thunderstorms. - Weather quiets down midweek. && .DISCUSSION... Issued at 157 PM CDT Sat May 25 2024 After a fairly pleasant day, a 35 to 50 kt LLJ will bring in moisture from the southwest and destabilize the atmosphere this afternoon and evening. This should spawn some thunderstorm activity. While the parameter space is not overly remarkable, it also isn`t weak. Deep layer shear is hovering around 50 kt with CAPE sub-1000 J/kg. Updraft Helicity is not great, but there is a couple hour window late this afternoon along a baroclinic zone that extends from Brainerd to Duluth and slightly eastward into NW WI that could be a focal point for the stronger storms. Already see a little convection going up west of St. Cloud and the preceding visible satellite field is indicative of a high shear environment with decreasing stability. Steep low level lapse rates are also developing with all of the insolation that occurred earlier in the day. All this to say, that it could be a bit active over the next 3 to 6 hours before setting down overnight. While it does calm down thunderstorm-wise, there still will be moisture advecting along this same boundary overnight causing lighter rain. May have to watch for minor flooding if cells train given our recent influx of water. Tonight clouds clear near Koochiching County allowing for just enough cold air to warrant a Frost Advisory. The next system on deck will cross Sunday afternoon but largely miss us to the south. This system does have a high PWATS and some potential to provide heavy rainfall across the southern portion of our forecast area in NW WI. A fast-moving clipper follows for a little more rain on Monday and an upper low on Tuesday into Wednesday for more shower activity. High pressure builds Wednesday and should linger into Friday giving us a short dry period before the next trough brings a return of rain for the start of next weekend. && .AVIATION /00Z TAFS THROUGH 00Z MONDAY/... Issued at 708 PM CDT Sat May 25 2024 An area of showers and embedded thunderstorms is working across northwestern Wisconsin early this evening and will exit the region over the next few hours. Conditions have remained VFR for the most part with this activity with a few briefs dips to MVFR. Additional rounds of showers with some embedded thunder will continue through much of the remainder of the period. Overall conditions are expected to remain VFR with perhaps some brief dips to MVFR when any showers move over a terminal. Confidence in timing on this is low, so have treated with VCSH for the most part. Better chances for rainfall are expected Sunday afternoon at HYR and have added a period of prevailing rain there. Gusty winds this evening will diminish after sunset with generally light and variable winds overnight. Winds Sunday will be around 10 knots or less. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 157 PM CDT Sat May 25 2024 Pesky southwest winds have been slow to subside, so extended the small craft into this evening. Thunderstorms will disrupt the flow a bit this evening leading to a much quieter night wind- wise over the waters. Winds will stay fairly quiet for the remainder of the weekend except near the Twin Ports where they will get close to 20 kt by Sunday afternoon - may need some small crafts for this. For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...Frost Advisory from 4 AM to 9 AM CDT Sunday for MNZ010. WI...None. MARINE...Small Craft Advisory until 10 PM CDT this evening for LSZ121- 140>148-150. && $$ DISCUSSION...Wolfe AVIATION...BJH MARINE...Wolfe