867 FXUS63 KDLH 031127 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 627 AM CDT Sat Jun 3 2023 .DISCUSSION...(Today through Friday) Issued at 425 AM CDT Sat Jun 3 2023 Summary...The main concerns this forecast are for the backdoor cold front due to drop through the area in the Sunday night-Monday time frame with associated precipitation chances and cooler temperatures. Between now and then diurnally driven showers and storms are expected through the weekend. Upper level ridging to our west for much of the forecast period will leave us with only intermittent precipitation chances, though additional shortwaves in the Tuesday through Friday time range will bring precipitation chances this week. Precipitation chances today and Sunday will be very similar to what we had on Friday, with mainly diurnally driven showers and isolated storms. Have kept pops on the low side both days, though locations that do get showers may get a brief heavy downpour. There should be at least some focused along the lake breeze front both days. Temperatures will continue to warm through the weekend with highs inland in the 80s and 20 or more degrees cooler near Lake Superior. The effect may be weaker Sunday with weaker surface winds, though a lake breeze will likely penetrate farther inland than it does on Saturday. Those with outdoor activities to do this weekend should be sure to take advantage of these weather conditions. Sunday night and Monday a backdoor cold front will slide through the area accompanied by a shortwave will bring precipitation chances and a shot of cooler temperatures. East to northeast flow off Lake Superior will bring even cooler temperatures to areas near Lake Superior on Monday. It will also drive some of the humidity out of the area. Dewpoints in the 50s through the weekend will be driven back down into the 30s and 40s by Tuesday, which will push minimum RH values into the 20-30 percent range. The north to northwest flow continues aloft through much of the work week. While ridging builds into the region, the edge of it remains in our vicinity throughout the week, and with even a weak shortwave moving through the flow we will get showers and thunderstorms fairly easily. Have included small slight to chance pops for much of the work week. The cooler temperatures on Tuesday will gradually moderate and warm through the week, rising back into the 80s Thursday and Friday. && .AVIATION...(For the 12Z TAFS through 12Z Sunday morning) Issued at 627 AM CDT Sat Jun 3 2023 Stratus and fog around Lake Superior this morning is expected to slowly dissipate as temperatures gradually warm. So far this has stayed out of KDLH, and unless it affects the terminal by 14z it will not this morning. Further inland, radiation fog is affecting a few other locations with MVFR visibilities. These should lift quickly now that the sun has risen, and expect all visibilities to return to VFR by 14z. The fog should linger around Lake Superior through the day as onshore lake winds continue. Additional showers/storms will develop with the heating of the day today as the warm and moist airmass remains in place. Coverage is expected to be spotty, but had enough confidence to include VCTS groups for KBRD, but it appears they will stay away from the other terminals for now. Fog and stratus is expected to develop once again tonight, especially around Lake Superior, and have included MVFR visibilities beginning after 06z for a few sites where the fog is most likely. && .MARINE... Issued at 425 AM CDT Sat Jun 3 2023 Northeast winds on Lake Superior today will cause building waves, but since winds will be only 5 to 15 knots will keep waves from building over 2 waves. Winds will be lighter on Sunday with a weak pressure gradient. The humid airmass over the area has already produced fog over the lake which has streamed inland, is should dissipate at least somewhat during the day today before re-forming once again tonight. The existing Dense fog advisory over the lake may well need to be extended today. Even if the fog dissipates today, it is likely to re-form once again tonight and we may need an additional advisory tonight. A back door cold front will bring stronger northeast winds on Monday and Monday night, causing building waves into the western arm of Lake Superior. Conditions hazardous to Small Craft are likely to develop on Monday and Monday night. && .PRELIMINARY POINT TEMPS/POPS... DLH 76 53 81 55 / 10 10 20 30 INL 90 61 88 62 / 20 20 50 40 BRD 88 60 89 64 / 30 20 20 20 HYR 91 57 89 58 / 20 10 10 20 ASX 73 48 78 49 / 20 10 20 30 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Dense Fog Advisory until 10 AM CDT this morning for LSZ121- 140>148-150. && $$ DISCUSSION...LE AVIATION...LE MARINE...LE