479 FXUS63 KDLH 060856 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 356 AM CDT Wed Oct 6 2021 .DISCUSSION...(Today through Tuesday) Issued at 351 AM CDT Wed Oct 6 2021 Summary: Quiet and mild weather today except for some areas of fog, especially near Lake Superior. Some rain chances move in as early as Thursday, but better chances on Friday and into the weekend. Temperatures cool off a bit next week. Fog and low stratus continue to persist over a good portion of the region this morning, particularly across the Arrowhead, near Lake Superior, and into parts of northwest Wisconsin. A warm air mass aloft with persistent southerly return flow is trapping low-level moisture near the surface, and with the aid of a light easterly component over Lake Superior, the fog and stratus is not likely to disappear quickly today, even after sunrise, though it will gradually lift for most areas going into the afternoon. Aside from the fog, temperatures will remain mild today with highs right around 70 degrees with some sunshine developing. Surface high pressure centered east of Lake Superior with elongated low pressure over the western Dakotas will create a tightening pressure gradient especially over western Minnesota. This may cause some gusty southerly winds for western parts of the region today. More fog, dense at times, is likely tonight especially near Lake Superior, but otherwise quiet weather is expected. A closed low over the south-central states will move north on Thursday into Friday, bringing a stream of moist air up to the region and introducing a chance for showers mainly for southern parts of the region on Thursday. A better chance for showers and possibly a few thunderstorms will occur on Friday with a bit more instability in place. A potentially larger system may impact parts of the region over the weekend as a Colorado low deepens associated with a potent upper level trough. This could bring some windy conditions, periods of moderate to heavy rain to some places, and a few thunderstorms. There remains a good amount of uncertainty with this system as far as timing and intensity, so expect some forecast changes in the coming days. Temperatures are likely to cool off a bit behind this system going into early next week. && .AVIATION...(For the 06Z TAFS through 06Z Wednesday night) Issued at 1241 AM CDT Wed Oct 6 2021 Dense fog with IFR to LIFR ceilings is likely through the night and likely lingering through the morning at DLH/HIB, aided by onshore flow from Lake Superior. HYR may also see periods of fog and MVFR to IFR ceilings tonight and into Wednesday morning. INL/BRD will likely remain VFR tonight, though some brief periods of fog can't be completely ruled out. Fog will lift for the most part Wednesday afternoon, though some afternoon MVFR ceilings can't be ruled out at DLH. Otherwise, expect VFR conditions. Winds may become breezy from the south at BRD/INL due to a tightening pressure gradient to the west Wednesday afternoon. Fog will likely develop again Wednesday night, especially near Lake Superior. && .MARINE... Issued at 351 AM CDT Wed Oct 6 2021 No major issues anticipated in the next 48 hours involving winds or wave heights. Departing high pressure will keep winds light from the east with wave heights two feet or less. Fog is likely to be a periodic issue today and again tonight over the nearshore waters of Lake Superior. Dense Fog Advisories are in effect for most nearshore zones through mid-morning this morning, and additional headlines may be needed again tonight. The latest weather models suggest that the fog may persist into Friday. An area of low pressure approaching the region from the southwest over the weekend may result in some stronger winds, which may create conditions that could be hazardous for small craft. && .PRELIMINARY POINT TEMPS/POPS... DLH 67 55 67 56 / 10 10 20 40 INL 74 56 72 57 / 0 0 10 30 BRD 71 57 70 57 / 0 10 20 30 HYR 71 52 70 56 / 0 10 30 40 ASX 72 51 72 55 / 10 10 20 40 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...Dense Fog Advisory until 10 AM CDT this morning for WIZ001>004. MN...Dense Fog Advisory until 10 AM CDT this morning for MNZ012- 019>021-037. LS...Dense Fog Advisory until 10 AM CDT this morning for LSZ121- 142>148-150. && $$ DISCUSSION...JDS AVIATION...JDS MARINE...JDS