Expires:No;;142255 FXUS63 KDLH 040547 AFDDLH Area Forecast Discussion National Weather Service Duluth MN 1147 PM CST Tue Dec 3 2024 .KEY MESSAGES... - Moderate snowfall in the Arrowhead lasts through this evening, locally heavy in Cook County. - South Shore snowbelt lake effect begins Wednesday morning and lasts into Thursday morning. Heavy snowfall is expected in northern Iron County. - Gusty northwest winds begin Wednesday morning and last into Wednesday night, strongest along the North Shore. - Isolated snow squalls are possible Wednesday mainly in far northern Minnesota. - A couple more chances for snow across the Northland will return this weekend. && .DISCUSSION... Issued at 315 PM CST Tue Dec 3 2024 ARROWHEAD SNOW - Mean northwesterly flow resides over the entire Midwest this afternoon as longwave troughing occurs over eastern North America. A quick moving low pressure centered in northern Manitoba drops southward tonight. Ongoing moderate snowfall that is forecast around 18:1 in the Arrowhead under still-cold enough air is forecast to turn over to more traditional 10:1 snowfall as a warm front lifts through the region this afternoon. While all precipitation is expected to remain as snow in the Northland, it will be fairly limited except along and north of the Iron Range and across the Arrowhead through tonight. With a forecast 2 to 5 inches occurring in the Interior Arrowhead from now through late evening tonight, a Winter Weather Advisory was issued early this morning for northern Cook and Lake Counties. High snowfall rates up to 1"/hr now through mid-evening in southern Cook County, along with the persistent forecast snowfall of 3 to 7 inches, resulted in the previous Advisory to be upgraded to a Winter Storm Warning. WIND AND BLOWING SNOW AND WIND CHILLS - Most accumulating and widespread impactful snowfall ends by late tonight as a cold front sweeps through the region early Wednesday morning. As the low pressure further deepens over southern Manitoba and northwest Ontario Wednesday morning, winds increase under strong cold air advection and an increased pressure gradient. Wind gusts to 45 mph are expected across much of central and northeast Minnesota tomorrow so Wind Advisories were issued for the Arrowhead down along the I-35 corridor and into the Brainerd Lakes region. Continued light snow showers in this time period and previous snowfall combines for areas of blowing snow Wednesday daytime. At this time the highest gusts are forecast along the North Shore. With the highest confidence in gusts to 60 mph in terrain funneled parts of southern Cook County, a High Wind Warning is now in effect Wednesday afternoon and overnight. With the forecast of 2 to 6 inches widespread of new snowfall in the last 24 hours, blowing snow remains in the forecast as well for the Arrowhead. Localized pockets of visibility less than 1 mile are possible during the strongest winds from mid-afternoon tomorrow through the pre-dawn hours early Thursday morning. As winds persist Wednesday night with gusts lingering of 25 to 35 mph and the cold air aloft progged at -21 C combine to create wind chills of -20 F across nearly all of the Northland. LAKE EFFECT SNOW - Lake effect snowfall along the South Shore begins Wednesday morning under the cold air advection regime as winds in the low-levels veer north-northwesterly. Forecast snowfall around 5 to 10 inches is currently expected in northern Iron County and 2 to 6 inches for southern Iron County sunrise Wednesday to sunrise Thursday. While there is a 50-60% chance of also seeing 3 to 4 inches in far eastern Ashland County, the coverage of this moderate snowfall was not quite as high for any kind of Winter Weather Advisory at this time. SNOW SQUALLS - Instability builds over the Iron Range and northward Wednesday morning through mid-day as a narrow wedge of mid-level moisture works into the region, all supported by vort lobes rotating through the mean stacked low. All of this said, localized heavy snow showers are most likely tomorrow from 11 AM to 5 PM. The heavy snow showers would then combine with background winds of 15 to 20 mph and gusts to 40 mph to potentially create very rapid reductions in visibility over isolated areas. For this hazard, a Special Weather Statement was issued for Koochiching and northern St. Louis Counties covering this Snow Squall potential. Any snow squall could bring a quick 1 to 2 inches of snowfall for these locations north of the Iron Range. Lake effect snowfall wraps up Thursday mid-day along the South Shore as high pressure over the Northern U.S. Plains slides into the Upper Midwest. Another clipper looks likely to drop into the region from the Canadian Plains Friday, but medium-range deterministic guidance has kept lower QPF for this system at this time so snowfall of less than a few inches is expected. Temperatures begin to warm Friday and are forecast in the 30s for daytime highs this weekend ahead of the next clipper that may pass over the region early next week. && .AVIATION /06Z TAFS THROUGH 06Z THURSDAY/... Issued at 1146 PM CST Tue Dec 3 2024 A Clipper system is dropping southeastward across the area during this forecast, with the main area of precipitation now sliding out of the area. Snow still lingers near KHYR with MVFR conditions possible for another hour before visibilities improve to VFR. The other terminals have returned to VFR visibilities and MVFR ceilings with intermittent snow showers/flurries. The current southerly winds will veer into the west to northwest overnight, generally in the 10 to 15 knot range with gusts around 20 knots. After 12z, expect winds to increase out of the northwest, with gusts increasing to around 30 knots, which will continue through the day on Wednesday. Blowing snow is likely after 15Z Wed and may create MVFR visibilities, especially at area terminals along and north of U.S. Highway 2. Scattered snow showers may also bring a brief drop in visibility during the day. && .MARINE /FOR NEAR SHORE WATERS OF WESTERN LAKE SUPERIOR/... Issued at 225 PM CST Tue Dec 3 2024 Southwest winds increase in speed this evening and create conditions hazardous to small craft with Small Craft Advisories in effect. Winds shift westerly early tonight and then northwesterly early Wednesday morning. Gale force wind gusts become widespread by mid-day tomorrow so Gale Warnings go into effect across all waters Wednesday afternoon. Guidance continues to support strongest winds gusting to 50 knots along the North Shore so the previous Gale Warnings has been upgraded to a Storm Warning from Silver Bay northward to Grand Portage. The strongest gusts are expected Wednesday mid-afternoon through late Wednesday night. Along with the very strong winds tomorrow, the Apostle Islands and along the central and northern North SHore zones is expected to see freezing spray. A Heavy Freezing Spray Warning was issued for locations that had the highest confidence in the gusts greater than 45 knots through early Thursday morning. A few more zones may need to be added in the head of the lake over the next few hours. For the open water discussion, refer to the NWS Marquette Area Forecast Discussion at weather.gov/mqt. && .DLH WATCHES/WARNINGS/ADVISORIES... MN...Winter Weather Advisory until midnight CST tonight for MNZ012. Wind Advisory from noon Wednesday to 3 AM CST Thursday for MNZ012-019-020-037. Winter Storm Warning until midnight CST tonight for MNZ021. High Wind Warning from noon Wednesday to 6 AM CST Thursday for MNZ021. Wind Advisory from 6 AM Wednesday to midnight CST Wednesday night for MNZ025-033>036-038. WI...Winter Storm Warning from 9 AM Wednesday to 6 AM CST Thursday for WIZ004. MARINE...Small Craft Advisory until noon CST Wednesday for LSZ121- 140>148-150. Gale Warning from noon Wednesday to 10 AM CST Thursday for LSZ121-143>148-150. Storm Warning from noon Wednesday to 10 AM CST Thursday for LSZ140>142. Heavy Freezing Spray Warning from noon Wednesday to 10 AM CST Thursday for LSZ140>142-150. && $$ DISCUSSION...NLy AVIATION...LE MARINE...NLy