FXUS63 KDLH 030535 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1235 AM CDT Sat May 3 2025 .KEY MESSAGES... - Light rain ending in NW WI later this afternoon and evening. - Areas of fog expected tonight into early Saturday morning, with the best potential for dense fog (40-60%) in east-central MN and near the Twin Ports. - Quiet and dry weather for the weekend and early next week with highs climbing to above normal, with widespread highs in the 70s away from Lake Superior. && .DISCUSSION... Issued at 325 PM CDT Fri May 2 2025 Rest of Today: Regional radar and surface observations show light rain in NW WI this afternoon associated with a weak surface low/inverted trough in south-central WI. As this low continues tracking southeast, the light rain will end late this afternoon into early evening for NW WI. Mostly cloudy skies across the area this afternoon will also gradually clear out later this evening as the system departs. Tonight - Saturday Morning: High pressure moves overhead tonight, with winds becoming very light to calm. Lingering near-surface moisture due to recent rainfall and some radiational cooling tonight into early Saturday morning should combine to produce areas of fog near the southwest Arm of Lake Superior, including the Twin Ports, east- central MN, and NW WI. There is a 40-60% chance for the development of Dense Fog for the Twin Ports and east-central MN overnight, but confidence was too low at this point to issue a Dense Fog Advisory. If models continue to trend higher in confidence regarding dense fog potential tonight, then a Dense Fog Advisory may be needed. Low temperatures tonight should range from the upper-20s in north-central WI to low to mid-30s elsewhere. This Weekend - Early Next Week: A prolonged period of warmer and drier weather is in store for the Northland for this weekend into early next week as an upper-level ridge pushes into the Upper Midwest. This pattern is poised to hang around for several days as an omega block sets up with upper-level lows in the Desert Southwest and Ohio River Valley. As a result, the Northland will warm above average (normals in the upper 50s to low 60s) with highs in the 60s to near 70 on Saturday and widespread 70s on Sunday-Tuesday. Areas near Lake Superior should remain cooler, with onshore northeast winds leading to lake breezes during the late afternoon into evening of both Sunday and Monday. The main concern during these days will be the potential for near-critical fire weather conditions given several days with a lack of precipitation and afternoon minimum relative humidities dropping into the 25-35% range for most, particularly on Sunday. Aside from wind gusts to around 20-25 mph in northern MN Saturday, wind gusts should remain under 20 mph Sunday through Tuesday. The next chance for rain (10-30% chance) is with a weak cold front/subtle shortwave trough Tuesday/Tuesday night, but rainfall amounts look minimal at best. Beyond Tuesday, there are some signals for the omega block to break down in the ensemble guidance for Wednesday into the second half of next week, but model consistency diverges during the latter half of the week as models tend to break down these blocking patterns too quickly, so confidence is lower in the forecast beyond Tuesday. With that said, the CIPS Extended Analogs and CPC forecasts continue to favor above-average temperatures largely persisting into at least the middle of May. && .AVIATION /06Z TAFS THROUGH 06Z SUNDAY/... Issued at 1234 AM CDT Sat May 3 2025 MVFR stratus lingers over NW WI this evening with the latest trends showing some erosion on its northern periphery through the Twin Ports. Models are not doing the best of job handling this moist layer so confidence in its departure time is low. For now we are leaning towards it dissolving by late morning. Additionally, we are seeing some fog development across portions of the Northland. Any fog that does develop is not expected to linger long through Saturday morning. Expect widespread VFR conditions by 15Z for the Northland. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 325 PM CDT Fri May 2 2025 Light winds today turn southwesterly tonight as low pressure over southern Wisconsin departs and high pressure moves into the region. There is a little bit of a pressure gradient that sets up for daytime Saturday with gusts of 10-20 knots, highest near Grand Portage, though hazardous conditions to smaller vessels are not expected. The calm/lighter winds tonight along with rain recently falling into the marine layer will likely lead to fog development tonight into Saturday morning, particularly for the head of the Lake. There is around a 40-60 percent chance for dense fog to develop in the head of the Lake, but confidence isn't high enough in the fog being widespread enough to issue a Dense Fog Advisory at this point. Winds turn back out of the northeast on Sunday and Monday as elongated surface high pressure persists for the region, with wind funneling in the southwest arm of Lake Superior leading to gusts of 15-20 knots both days and weaker gusts elsewhere. 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...Rothstein AVIATION...Britt MARINE...Rothstein