FXUS63 KDLH 240639 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 139 AM CDT Mon Aug 24 2026 .KEY MESSAGES... - The next chance for showers and storms will be tonight through Tuesday and again Wednesday. - Severe storms are possible, particularly Tuesday afternoon and evening with the passage of a cold front. - Seasonal, dry conditions return for the later part of this week. && .DISCUSSION... Issued at 136 AM CDT Mon Aug 24 2026 Current conditions/this morning: High pressure is slowly sliding east this morning, with light and variable winds. Satellite imagery is showing some high level clouds pushing into the area from the west, but we will still have good radiational cooling conditions, and while I do not expect us to get quite as cold as last night, it will still be cool with lows in the 40s and perhaps upper 30s. Conditions will also be good for fog, bringing some patchy dense fog that will burn off quickly after sunrise. Today: Southerly warm air advection will push highs up into the mid 70s to around 80 across the area. We have been watching the potential for showers and thunderstorms approaching the area with a wave of warm air advection early this morning, which we can see have developed over northern North Dakota as of 1 AM. However, most mesoscale analysis does not support this convection getting much farther east than it already is, and should deteriorate to mainly cloud debris before it gets to the Northland. Precipitation chances increase tonight as the main upper level shortwave moves across the area Tuesday into Wednesday. Tonight there will be enough instability and decent deep layer shear to initiate convection over eastern North Dakota, then gradually slide east overnight. However, like tonight, the instability and shear weakens significantly to the east, and the storms are likely to weaken and dissipate as they move east. We do have a sliver of Marginal severe risk just to our west from SPC, but it and the even farther west Slight risk are likely to be the main concern of the night and am less concerned for the Northland. Tuesday: Warmer and more humid conditions push into the area, with surface based instability developing during the afternoon and evening hours. Then, just as the upper level shortwave moves across the area and deep layer shear parameters increase, there will be another wave of showers and thunderstorms which move across the Northland. These storms will have the potential to be strong to severe storms, with a few storms capable of producing 1" hail and damaging winds. SPC has a marginal risk (level 1 out of 5) outlined for all of the Northland. Showers and non-severe storms will redevelop across the area on Wednesday in the cyclonic flow behind the upper level shortwave. While we will have mostly cyclonic flow on Thursday, the surface ridge building into the area and low level dry air should keep anything but diurnal cumulus from forming. Wednesday and Thursday will be cooler again as well. Dry and seasonable conditions to continue into Friday with high pressure lingering over the area. Weak upper level ridging builds into the area for the weekend, with poor predictability for precipitation chances as weak shortwaves may slide through the flow aloft and bring a round of showers/storms. The forecast has some low end chances for precipitation, but these may be more limited than is currently depicted. Temperatures should remain near normal through the weekend. Another potent upper level low will progress across the area early next week, which may bring another round of higher confidence precipitation chances. && .AVIATION /06Z TAFS THROUGH 06Z TUESDAY/... Issued at 1237 AM CDT Mon Aug 24 2026 VFR conditions as of issuance time are expected to give way to areas of fog, some of it at dense. Some indications for fog are higher this evening, with higher dewpoints, but we are not expected to get as cold tonight as we did yesterday. Have included MVFR/IFR visibilities for the same terminals which got fog last night, mostly with TEMPO groups due to the variability which is expected with the fog. As usual, the fog will burn off shortly after sunrise. Light winds overnight into Monday morning will gradually become southeasterly, but remain less than 10kts. && .MARINE /FOR NEARSHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 136 AM CDT Mon Aug 24 2026 Quiet conditions are expected across Western Lake Superior through today and tonight with waves of 1 foot or less and winds becoming easterly at generally less than 10 knots. Winds increase a little out of the southeast on Tuesday, along with shower and thunderstorm chances. We should have an initial wave of them Tuesday morning. Additional storms will develop during the afternoon and evening, some of which may be strong to severe. Shower chances to linger into Wednesday. For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .FIRE WEATHER... Issued at 136 AM CDT Mon Aug 24 2026 High pressure slides to our east today, allowing moisture to begin to push into the area from the west. Relative humidity values to be low again for the MN Arrowhead and northwest Wisconsin, but farther west in Minnesota RH values will increase to over 40 percent. Winds will become southerly today, and may gust around 10 mph during the afternoon for parts of the area. Shower and thunderstorm chances increase for Monday night through Wednesday, most especially on Tuesday afternoon and evening, when some storms may become strong. RH values to remain above 40 percent for both Tuesday and Wednesday. Precipitation chances are highest along and north of the Iron Range, but most areas have at least a 40 percent chance of a wetting rainfall. See the Fire Weather Forecast product for a more thorough breakdown of fire weather conditions. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. MARINE...None. && $$ DISCUSSION...LE AVIATION...LE MARINE...LE FIRE WEATHER...LE