A low pressure system tracked through northern Wisconsin during the early afternoon hours of February 28. Mainly snow fell across far northern Wisconsin with a mix of snow, rain, and freezing drizzle across central and northeast Wisconsin.
Every event with a place to put it; 2 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
Deaths and injuries are direct and indirect together, as the offices filed them. Damage is property and crops in the dollars of the year, not adjusted for inflation, and only where an office estimated it.
The episode as NWS GRB wrote it up.
A low pressure system tracked through northern Wisconsin during the early afternoon hours of February 28. Mainly snow fell across far northern Wisconsin with a mix of snow, rain, and freezing drizzle across central and northeast Wisconsin. A heavy band of 6 to 9 inches of snow fell across Vilas County, with 4 to 5 inches across northwest Oneida County in a few short hours.
Some of the higher snowfall totals included 8.8 inches 9 miles east northeast of Boulder Junction (Vilas Co.), 7.3 inches near Boulder Junction (Vilas Co.), 6 inches near Phelps and Eagle River (Vilas Co.), and 5 inches near Willow Reservoir (Oneida Co.).
The local office's own words before the first event, as it sent them, from the Iowa Environmental Mesonet's archive of National Weather Service text.
NWS Green Bay, WI wrote its last area forecast discussion before the first event at Feb 28, 6:31 AM CST, 2 hours 29 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Green Bay WI 631 AM CST Sun Feb 28 2021 New Information added to update section .UPDATE... Issued at 624 AM CST Sun Feb 28 2021 Considered a FG.Y for eastern Wisconsin, but RAP and HRRR vsby progs are in good agreement in showing the fog steadily shifting WWD this morning. This seems reasonable given increasing ESE flow and webcams/sfc obs along the lake are showing this happening too with MTW now up to 1SM. So given the transient nature of the fog and it's limited time in any given area, opted for an SPS instead of an advisory. Otherwise, dry air continued to hold off the precipitation. But the dry air was rapidly being overcome in western Wisconsin, and precipitation should expand ENE across the NW 1/2 of the forecast area very quickly during the next several hours. Extrapolation of the southern edge of the cold cloud tops in the deformation zone continues to take them across far N-C WI, so the warning for Oneida and Vilas still looks on track. && .SHORT TERM...Today Issued at 502 AM CST Sun Feb 28 2021 Quite a complex forecast this morning. A vigorous but fast moving cyclone will race across the region today. The updated snowfall forecast was right at 12 hour warning criteria (6"). However, feel there will be a period of very nasty travel conditions across far N-C WI mid-day as the heaviest snow occurs (perhaps some 1-2" per hour snowfall rates.) That was the critical factor in the decision to take Oneida and Vilas up to a warning. Even if totals fall a little short of the 6" criteria, the travel impact is likely to be significant for anyone out on the roads mid-day. Elsewhere, adjusted the end time of the advisory along it's southern extent. Travel impacts in this area will likely occur this morning due to some FZRA. The boundary layer should warm enough by afternoon to allow conditions to improve. Also ended up delaying the start time of all the headlines to better line up with the arrival of the precipitation. Otherwise, FG was expanding in E-C WI as higher dew points arrive in the area. Watching webcams, and conditions don't seem bad enough to warrant a FG.Y yet. But will continue to monitor and post an advisory if the visibility continues to drop. The added wrinkle is a few obs reporting light precipitation. Changed the WSR-88D to VCP 31 to get a better look at the light returns. Watching to see of those continue to expand, indicating more widespread DZ is occurring. That would be a problem because temperatures away from the lake will be AOB freezing for a few more hours. And of course it doesn't take much FZDZ to make roads very slippery. .LONG TERM...Tonight Through Saturday Issued at 407 AM CST Sun Feb 28 2021 Main focus in the long term will be a fast moving clipper system bringing snow showers to the area late tonight into Monday. Otherwise, a very quiet stretch of weather is expected across the area next week as split upper flow dominates most of the CONUS. Temps briefly fall below normal on Monday, then near or above normal readings are expected but the models have back away on the spring-like temps. Sunday night into Monday...lingering light lake effect snow showers and flurries will be possible across far northern WI, especially Vilas Co., in the early evening with little to no accumulation expected. Then attention turns to a fast moving clipper system diving across the area. Models continue to show a surface cold front, accompanied by a mid-level shortwave and upper support from the left entrance region of a 120 kt jet. Soundings showing a saturated (for a short time), fairly isothermal layer from the surface to around 10,000 ft, along with a brief period of decent lift in the DGZ, and with steep mid- level lapse rates. Northwest flow over Lake Superior could add a little extra boost to the activity as well. This will all lead to a round/burst of snow showers across much of the area, near/behind the surface front. Models has slowed the arrival slightly, and there still is a little uncertainty if/where a "heavier" band of snow will fall as the the area could be rather small (focused over central WI this model run). Models remain fairly skimpy on the QPF as the system lacks deep layer moisture, is fast moving, and there is some dry air at the lower levels to overcome. But some meso models are a little higher and with dynamics in play, did bump up amounts a little but snow totals remain under an inch. It will be a fluffier snow as well, with snow ratios generally between 13:1 and 20:1. Northwest winds gusting up to 20-25 mph could produce some minor blowing/drifting snow. While amounts will be on the low side, there the quick burst of snow before/during the Monday morning rush could make for a more impactful event (especially north and west of the Fox Valley based on current timing). The snow will end by 18z, with the exception of northern WI where delta T's near 20 and a northwest flow could keep some flurries going into the afternoon. CAA will crash 850mb temps to between -13C and -19C (far northeast WI) which will help keep highs in the teens and 20s. Rest of the long term...split upper flow will bring very quiet late winter conditions to the area. Surface high pressure slides over the area Monday night then shifts southeast of the region on Tuesday. Closed low still forecast to track well south of the region mid-week, with a weak shortwave trough pushing across the northern Great Lakes. Looks like any precip with this shortwave will stay north of the area. South winds and mixing up to 925mb should allow highs to climb into the 40s for most spots on Tuesday. Still some uncertainty on just how warm temps will get the rest of the week. The MEX guidance for Green Bay dropped by 15 degrees for Thursday from 24 hours ago. Models have shifted to more of a northerly flow mid to late week as high pressure extends south of west of Hudson Bay. This setup would make getting to the 40s challenging. Nudged highs down a little from the model blend, but if this trend continues, would have to keep lowering temps. && .AVIATION...for 12Z TAF Issuance Issued at 502 AM CST Sun Feb 28 2021 FG/ST was already resulting in some LIFR conditions near the lake early this morning. Conditions across the rest of the area will quickly drop to IFR/LIFR as precipitation develops northeast across the area. Improvement will occur this afternoon as the storm system generating the precipitation races through the area and off to the northeast. && .GRB WATCHES/WARNINGS/ADVISORIES... Winter Weather Advisory until 3 PM CST this afternoon for WIZ011- 012-018-019. Winter Weather Advisory until noon CST today for WIZ013-021-030. Winter Storm Warning until 6 PM CST this evening for WIZ005-010. && UPDATE.........Skowronski SHORT TERM.....Skowronski LONG TERM......Bersch AVIATION.......Skowronski
Hazardous Weather Outlook National Weather Service Green Bay WI 654 AM CST Sun Feb 28 2021 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-011200- Vilas-Oneida-Forest-Florence-Northern Marinette County-Lincoln- Langlade-Menominee-Northern Oconto County-Door-Marathon-Shawano- Wood-Portage-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago- Calumet-Manitowoc-Southern Marinette County- Southern Oconto County- 654 AM CST Sun Feb 28 2021 This Hazardous Weather Outlook is for north-central and northeast Wisconsin. .DAY ONE...Today and Tonight A band of dense fog shifting west off Lake Michigan will produce hazardous travel conditions in eastern Wisconsin for a time this morning. Travel conditions north and west of the Fox Valley will deteriorate quickly during the middle to late morning. Mainly snow is expected across north-central Wisconsin, while a mix of snow, sleet and freezing rain occurs from central through northeast Wisconsin. The hazardous travel conditions will continue into the afternoon across north-central Wisconsin. Warming temperatures will allow much of the mixed precipitation from central through northeast Wisconsin to transition to rain or a rain/wet snow mix. .DAYS TWO THROUGH SEVEN...Monday through Saturday A round of snow showers late tonight night into Monday morning may leave roads slick for the Monday morning commute. .SPOTTER INFORMATION STATEMENT... Spotters are requested to report snowfall measurements and any instances where roads become icy due to freezing rain. LMZ521-522-541>543-011200- The Bay of Green Bay south of a line from Cedar River MI to Rock Island Passage-Lake Michigan from Washington Island to Sheboygan- 654 AM CST Sun Feb 28 2021 This Hazardous Weather Outlook is for portions of northwest Lake Michigan and the waters of Green Bay. .DAY ONE...Today and Tonight The probability for widespread hazardous weather is low. .DAYS TWO THROUGH SEVEN...Monday through Saturday The probability for widespread hazardous weather is low. Skowronski
Special Weather Statement National Weather Service Green Bay WI 611 AM CST Sun Feb 28 2021 WIZ022-038>040-048>050-073-074-281400- Door-Outagamie-Brown-Kewaunee-Winnebago-Calumet-Manitowoc- Southern Marinette County-Southern Oconto County- 611 AM CST Sun Feb 28 2021 ...DENSE FOG WILL RESULT IN HAZARDOUS TRAVEL CONDITIONS FOR A TIME OVER EASTERN WISCONSIN THIS MORNING...... Moisture arriving in the area on light southeast winds resulted in the formation of fog over Lake Michigan overnight. The fog will shift northwest across the area this morning as winds begin to increase from the southeast. While the fog is moving through, the visibility could drop to less than 1/4 mile for a couple hours, resulting in hazardous travel conditions. Temperatures will be slowly rising from near the freezing mark. Pavement temperatures may be a little slower to warm, so it is possible for some icy patches to develop on untreated roads, sidewalks, and parking lots. Be sure to slow down and use your low-beam headlights if you are traveling across eastern Wisconsin this morning. Allow extra distance between your vehicle and other vehicles on the road, and be alert for the possibility of slippery spots due to ice. Skowronski
Special Weather Statement National Weather Service Green Bay WI 746 AM CST Sun Feb 28 2021 WIZ022-031-037>040-045-048-049-073-074-281700- Door-Shawano-Waupaca-Outagamie-Brown-Kewaunee-Waushara-Winnebago- Calumet-Southern Marinette County-Southern Oconto County- 746 AM CST Sun Feb 28 2021 ...DENSE FOG WILL RESULT IN HAZARDOUS TRAVEL CONDITIONS OVER PORTIONS OF EASTERN AND CENTRAL WISCONSIN THIS MORNING...... Look for areas of dense fog across portions of central, northeast, and east-central Wisconsin this morning. The fog is expected to shift northwest across the area this morning as winds begin to increase from the southeast. While the fog is moving through, the visibility could drop to less than 1/4 mile for a couple hours, resulting in hazardous travel conditions. Temperatures will be slowly rising from near the freezing mark. Pavement temperatures may be a little slower to warm, so it is possible for some icy patches to develop on untreated roads, sidewalks, and parking lots. Be sure to slow down and use your low-beam headlights if you are traveling across the area this morning. Allow extra distance between your vehicle and other vehicles on the road, and be alert for the possibility of slippery spots due to ice. Kurimski
The national radar mosaic for the moment the first event began.
1 heavy snow, 1 winter weather. Local standard time, as filed.
The highest snowfall totals across Vilas County included 8.8 inches 9 miles east northeast of Boulder Junction, 7.3 inches near Boulder Junction, and 6 inches near Eagle River and Phelps.
The highest snowfall totals across Oneida County included 5 inches near Willow Reservoir and 4.8 inches near Hazelhurst.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Wisconsin in 2021Every state in 2021This day in weather historyWarnings in Wisconsin, February 2021
NOAA National Centers for Environmental Information, Storm Events Database, compiled from the National Weather Service’s monthly Storm Data. Complete through 2026-06; NCEI adds each month about 75 days after it ends and revises past years a few times a year. Rebuilt 2026-09-24. Each event’s entry at NCEI: 937447, 937487.