917 FXUS63 KDLH 172334 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 634 PM CDT Wed May 17 2023 .DISCUSSION...(This evening through Tuesday) Issued at 252 PM CDT Wed May 17 2023 Summary: A cold front will be entering from the west this evening bringing showers and storms tonight through Thursday. There is a marginal risk for severe storms to develop tomorrow afternoon across Price and southern Iron and Ashland counties. Near surface smoke may filter in behind the front beginning early tomorrow morning. There is an Air Quality Alert in place beginning tonight and running through noon tomorrow. Additional rain chances will persist into Friday before clearing out this weekend for some quiet weather. An upper level low sitting over central Canada combined with our NW winds aloft continues to pour smoke covered skies into the region due to the wildfires across Alberta and the NW territory. The Northland will find itself wedged between an exiting high over eastern Lake Superior and an incoming low across the southern Canadian Prairies. The increased pressure gradient between these two features will surge southerly winds across the region. A cold front will be marching in from the west this evening spreading showers and thunderstorms throughout the night and Thursday. With the system dropping from the NW it will not pack quite the punch as the lows that swing up from the Central Plains. PW values are steadily between 1 to 1.3 inches putting it close to climatological averages for this time of year. MUCAPE does build up a bit overnight as the LLJ ramps up but overall weak mid and low level lapse rates will keep damaging storms at bay. We will see increased chances for thunderstorms Thursday afternoon as the front moves into NW WI. This is highlighted well in the CAMs and coincides will with diurnal trends. Price and into southern Ashland and Iron counties is highlighted in a marginal risk for severe tomorrow afternoon. There is a very small window for some upscale growth and linear storm development before surface cooling quickly diminishes the chances. One last thing of note for this incoming system would be the chances for some near surface smoke to develop. Looking far out west over western ND we can see visibilities rapidly dropping behind the push of rain due to the sinking nature of the cold air advection. Stations have seen reductions down to less than 2 miles at times. The RAP model does highlight this smoke making into the Northland behind the system by early Thursday morning. We will need to monitor how this evolves over the west as it approaches as we may need a Special Weather Statement for the potential travel impacts the smoke could bring. As the cold front moves east a compact upper level low will cross the region for Friday and could promote some additional rain showers. Satellite trends today would suggest that there will be a fair amount of smoke mixed in with this upper level low but as it exits late Friday we should see some clearing skies. However, with northwest flow continuing over the region upper level smoke may filter back in later in the forecast. This weekend is expected to be quiet with Saturday sporting widespread 70s. A colder air mass rotating across Ontario for Sunday may bring some cooler temps to the Northland. There still seems to be some discrepancies with the deterministic guidance on how cold the air mass will be and the extent of it's reach. Some frost advisories may be warranted for Sunday night. && .AVIATION...(For the 00Z TAFS through 00Z Thursday evening) Issued at 634 PM CDT Wed May 17 2023 A cold front will sweep through the Northland tonight into Thursday causing showers and a few thunderstorms behind it. Ceilings will lower to MVFR overnight into Thursday morning then increase through the day Thursday. A few thunderstorms will be possible but we mainly just went with showers tonight. A few strong thunderstorms will be possible Thursday afternoon over parts of northern Wisconsin. Low level wind shear will develop at most locales tonight due to a low level jet. There remains plenty of smoke from Canadian wildfires across the region. Some of this smoke is expected to come to the surface behind the cold front reducing the visibility for a time. We've seen reductions below a mile in parts of North Dakota this aftenroon/evening. For now, we have reductions from 2-5SM and will adjust as confident increases with later updates. && .MARINE... Issued at 252 PM CDT Wed May 17 2023 Enhanced northeasterly flow near the head of western Lake Superior has brought in waves reaching 4 ft this afternoon. A Small Craft Advisory remains in effect for these areas into the evening hours. A cold front marching across the region tonight and tomorrow will bring some showers and thunderstorms across the Lake. There may be some brief gusty winds out of the south for Chequamegon Bay into Saxon Harbor. && .PRELIMINARY POINT TEMPS/POPS... DLH 45 63 41 58 / 10 90 60 30 INL 49 60 40 65 / 90 80 40 20 BRD 55 66 42 61 / 50 90 30 10 HYR 50 68 43 59 / 10 90 50 30 ASX 45 67 43 56 / 10 90 60 30 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory until 8 PM CDT this evening for LSZ144-145. && $$ DISCUSSION...Britt AVIATION...Melde MARINE...Britt