Area Forecast Discussion
Issued by NWS Duluth, MN
Issued by NWS Duluth, MN
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185 FXUS63 KDLH 120545 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1245 AM CDT Sun May 12 2024 .KEY MESSAGES... - Near-critical fire weather conditions are occurring this afternoon. Another day of near-critical fire weather conditions are expected tomorrow in northeast Minnesota. - Showers and thunderstorms are likely this evening through tonight as a cold front sweeps through. A storm or two in Koochiching County may become strong this evening, capable of producing wind gusts up to 50 mph. - As the cold front moves into northwest WI, a storm or two in Price County may become strong to severe on Sunday afternoon. Gusty winds up to 60 mph and hail up to 1" in diameter are the main concerns. - Dry conditions on Monday and Tuesday will give way to periodic chances for showers and thunderstorms mid to late this upcoming week into next weekend. && .DISCUSSION... Issued at 358 PM CDT Sat May 11 2024 Mostly dry conditions have been observed this afternoon as a 500mb ridge briefly sits over the Northland. This ridging over the CWA will be short-lived though as a shortwave trough moves into northern Ontario tonight. A vertically-stacked low pressure associated with this shortwave will be bringing an attendant warm and cold front into the CWA today through tomorrow morning. As of 20z, the warm front is approximately located along a line from northwest Koochiching County to Hibbing. Ahead of this front, scattered showers have developed in the Arrowhead. An appreciable amount of dry air in the low-levels, which has led to near-critical fire weather conditions in north-central MN today, will result in these showers largely falling as virga this afternoon. As the cold front approaches this evening into tonight, shower activity will become more robust within the warm sector over north- central MN into the Arrowhead. As the cold front propagates south into the CWA, isolated thunderstorms will be possible (30% chance) this evening into tonight. Instability will be marginal this evening with MUCAPE of 200-400 J/kg . However, favorable 0-6km bulk shear of around 30 knots could organize a few cells into strong thunderstorms, especially in Koochiching County this evening. The main concern with any strong storms that develop will be gusty winds up to 50 mph and pea sized hail. Conditions on Sunday will vary widely across the CWA as dry air filters in behind the front in northeast Minnesota and the front continues to propagate through northwest Wisconsin. For the MN side of the CWA, deep mixing is expected to occur and drop minimum RH below 25% in most locations. This will lead to near-critical fire weather conditions and borderline Red Flag Warning criteria north of the Iron Range, where northwest winds will be highest tomorrow. Also happening tomorrow will be a low 30% chance of strong to severe thunderstorms in Price County. While thunderstorm activity will decrease tonight, additional thunderstorm development will be possible on Sunday afternoon around Price County as diurnal heating increases instability. Possible severe hazards include gusty winds up to 60 mph and hail up to 1 inch in diameter. The region will see a brief break from the active pattern early this upcoming week as the CWA sits between low pressure systems. Conditions will be pleasant across the area on Monday and Tuesday, with high temps being around normal for mid May. Looking ahead, a wet pattern is very likely (70% chance) to return to the CWA mid to late this upcoming week. Timing discrepancies between deterministic models are currently large, but the general consensus is showers and thunderstorms arriving on Wednesday and continuing into Thursday. Low pressure centers from global ensembles reflect the high uncertainty in timing for this midweek system, with minimal agreement in the GEFS and ECMWF ensemble. Following this midweek system, an active pattern will continue with additional chances for showers and storms later this upcoming week into next weekend. && .AVIATION /06Z TAFS THROUGH 06Z MONDAY/... Issued at 1246 AM CDT Sun May 12 2024 Expect predominately VFR conditions for most terminals through the TAF period. There is a cold front situated from northeastern North Dakota into far northern Ontario will slide southeast through NE MN tonight into the morning and through NW WI later this morning into afternoon. Scattered showers and a few embedded thunderstorms continue ahead of the front mainly over northern and northeast Minnesota tonight. Some gusty and erratic winds to 20 to 30 knots are possible with these showers/storms for KINL through about 07-08Z and KHIB overnight to a lesser extent, though conditions are expected to remain VFR with the showers/storms due to dry air in the lower atmosphere. Most of the remainder of the Northland stays dry with VFR conditions today as the front tracks south. However, there is still a 40% chance for scattered showers/storms in parts of NW WI (including KHYR) this afternoon as the front will still be in the vicinity at that time. Southerly to southwesterly winds tonight (outside of showers/storms) will quickly veer to northwesterly behind the cold front, with gustier winds developing during the daytime hours due to deep mixing. Much of NE MN should see gusts to 20 knots, with far northern MN seeing up to 25 knots. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 1230 AM CDT Sun May 12 2024 Southerly winds this afternoon and evening will be relatively light, with gusts being at or under 15 knots. Showers and isolated thunderstorms are expected this evening into tonight. Strong to severe thunderstorms are not expected, although cloud-to-water lightning will be possible. Winds turn northwesterly tomorrow, with warmer temperatures leading to most of the stronger winds remaining over land. However, some gusts to 20 knots are possible immediately along the North Shore Sunday afternoon and early evening. Winds on Monday will be relatively light across much of western Lake Superior. Increasing northeasterly winds on Tuesday may necessitate Small Craft Advisories as wind gusts approach 22 knots, especially around the Twin Ports. For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. MARINE...None. && $$ DISCUSSION...Unruh AVIATION...Rothstein MARINE...Unruh