850 FXUS63 KDLH 160319 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1019 PM CDT Sat Oct 15 2022 .UPDATE... Issued at 1015 PM CDT Sat Oct 15 2022 Light widely scattered rain showers remain across northeastern Minnesota late this evening and over very limited parts of northwestern Wisconsin. Forecast updates have been made to track these PoP trends. Some showers could turn over to a rain and snow mix early tonight and then light snow by early Sunday morning. Tomorrow will feature another day of scattered showers over the Northland; yes, much like the last few days. Lake effect rain showers along the South Shore continue Sunday afternoon, but are very likely to turn over to snow showers by that evening. The Special Weather Statement is in effect for Ashland and Iron Counties to highlight this first notable lake effect snowfall event in far eastern Ashland County and across Iron County in northwestern Wisconsin into Monday. Localized amounts of 6-8" of snowfall are possible in the highlands of northern Iron County by Monday afternoon. Expect impacts to travel for those commuting Monday morning in these snowbelt regions. Other notable weather out of this continuous low pressure system will be very strong winds along the northern half of the North Shore starting late Sunday afternoon and building through the overnight hours. Wind gusts were increased a few knots with the evening forecast update, but have largely continued the trend of the last couple of days of gusts to 40 mph into Monday morning. Locations between Tofte and Grand Portage, but specifically around Grand Marais, could experience wind gusts closer to 45 mph in a few hour period of late Sunday night into Monday morning per forecast model soundings. .DISCUSSION...(This evening through Friday) Issued at 400 PM CDT Sat Oct 15 2022 Summary: Scattered rain and snow showers are expected to continue tonight. Lake-effect rain will likely begin around Iron County tonight and switch over to snow late Sunday afternoon. Snow accumulations in Iron County on Sunday through Monday afternoon may be as high as 6 to 8 inches. This could lead to potential travel impacts for the Monday morning commute. Much lesser snow accumulations of an inch or less will be possible along and north of the Iron Range. Temps will be on the upward trend starting mid-week, with highs likely returning to the 50s by Friday. Scattered rain and snow showers have been persisting this afternoon as a shortwave trough propagates through the CWA. This shortwave is the result of an upper-level low pressure system currently located over northern Ontario. This system is expected to eject several more shortwaves over the CWA throughout the weekend. This will result in precip chances remaining in the forecast for most of the CWA throughout the weekend. CAMs indicate that much of this precip will be scattered, potentially presenting as a series of horizontal convective rolls over northern Minnesota. Abundant cloud cover will keep high temps relatively cool for the remainder of today and tomorrow. Expect precip type to vary between rain and snow, as diurnal temps swing above and below freezing. The main inland forecast concern over the next few days will be lake- effect snow developing along the South Shore of Lake Superior. In addition, minor accumulations may also develop downwind of Lake of the Woods, Rainy Lake, and Kabetogama. As the upper-level low pressure system advects southeast, a surge of cold air at 850mb is likely to move over the CWA. Since winds will be from the north- northwest, this will maximize the available fetch over Lake Superior for Iron County and to a lesser extent, Ashland County. Lake sfc temps per latest obs around the South Shore are currently around 10-12 degC. Aloft, 850mb temps will start around -5 degC on Sunday morning and plummet to around -12 degC by Sunday night. This increased delta-T will likely up lake-induced CAPE from a few hundred J/kg on Sunday morning to near 1000 J/kg by Sunday night. Expect lake-effect rain to begin along the South Shore tonight and continue on Sunday. This rain is progged to transition to snow in the late afternoon to early evening on Sunday and persist through Sunday night into Monday. Snow accumulations on Sunday through Monday afternoon will be highest in Iron County. Ensemble plumes show 2 main clusters, with one being around the 5 inch mark and a second around the 7 inch mark. Forecasted on the higher end of ensemble members in this update, since snow totals have been on the upward trend in recent model runs. Impact-wise, the main window of concern will be Sunday night into early Monday morning. This will be the time-frame when the most snow will likely fall. This could lead to slippery conditions for the Monday morning commute. Outside of Iron County, snow accumulations tomorrow into Monday will be much less at an inch or less along and north of the Iron Range. Highest snowfall amounts outside of the WI lake-effect snowbelts will likely be found in the lee of Lake of the Woods, Rainy Lake, and Kabetogama Lake, where up to 1.5" of snow will be possible. Expect conditions to dry out starting Monday as the upper-level low pressure system propagates downstream. Winds will slowly shift more southerly throughout the week, which will result in WAA. This WAA will increase temps throughout the week, with highs returning to the 50s to near 60 by Friday and continuing into next Saturday. && .AVIATION...(For the 00Z TAFS through 00Z Sunday evening) Issued at 632 PM CDT Sat Oct 15 2022 Low pressure centered over northern Ontario continues to create widely scattered showers around and periodically over a few terminals early this evening. Rain could turn to snow closer to 02-04z from north to south, but kept with the temporary mention of rain showers for the time being with uncertainty still in that transition over in the next few hours. Area rain and snow mixed showers then persist through much of tonight mainly at INL/DLH/HIB. Northwesterly winds persist through the entire TAF period, but will gradually increase after 18z. TWM, CKC and other terminals along the North Shore should expect strong and gusty northwest winds starting around 21z Sunday and lasting into Monday. && .MARINE... Issued at 948 PM CDT Sat Oct 15 2022 Small Craft Advisories remain in effect from Grand Marais through the Apostle Islands for tonight and Sunday morning as northwesterly have started to gust to 25 kts in localized areas of these nearshore waters. A Small Craft was issued for late Sunday morning to evening for parts of the South Shore and far North Shore as well with increasing northwesterly wind gusts finally impacting those locations ahead of the expected near to well-above gale force gusts later that night. The Twin Harbors region was removed from the Gale Watch for decreased confidence in any kind of prolonged and/or widespread gale force gusts Sunday night and early Monday. Although, conditions will still be hazardous in waters around the Twin Ports and necessitated the now present extended Small Craft Advisory into Monday night. The Gale Watch remains in place for what appear to be possible borderline gale-force gusts Sunday evening in Chequamegon Bay and from Two Harbors to Silver Bay. Waters closer to Silver Bay have better potential for seeing those 34 kt gusts compared to further south towards Two Harbors. Waves will build along the South Shore Sunday and remain elevated through at least Monday night as north-northwest winds remain gusty. Visibility near Saxon Harbor and in immediate nearshore waters could be greatly diminished as well late Sunday night into Monday due to blowing snow from lake effect snow showers. && .PRELIMINARY POINT TEMPS/POPS... DLH 34 37 23 34 / 30 30 10 10 INL 32 33 21 33 / 50 30 10 0 BRD 34 38 25 34 / 10 10 0 0 HYR 34 39 23 35 / 30 40 30 20 ASX 36 41 27 37 / 40 60 50 40 && .DLH WATCHES/WARNINGS/ADVISORIES... WI...None. MN...None. LS...Small Craft Advisory from 11 AM to 7 PM CDT Sunday for LSZ121- 140-148. Gale Watch from Sunday evening through Monday evening for LSZ121- 143. Gale Warning from 7 PM Sunday to 10 PM CDT Monday for LSZ140>142- 146>148-150. Small Craft Advisory until 7 PM CDT Sunday for LSZ141>143-146- 147-150. Small Craft Advisory until 10 PM CDT Monday for LSZ144-145. && $$ DISCUSSION...Unruh AVIATION...NLY MARINE...NLY