A strong storm system tracked across the central Plains and through the Upper Mississippi Valley, sweeping a cold front through the region during the late evening hours of Friday (12/15) and early morning hours of Saturday (12/16). Strong wind gusts of 55 to 76 mph were observed behind this cold front for several hours across northeast Wisconsin.
Every event with a place to put it; 11 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 strong storm system tracked across the central Plains and through the Upper Mississippi Valley, sweeping a cold front through the region during the late evening hours of Friday (12/15) and early morning hours of Saturday (12/16). Strong wind gusts of 55 to 76 mph were observed behind this cold front for several hours across northeast Wisconsin. The winds led to pockets of tree damage and numerous power outages, leaving over 50,000 people without power in northeast Wisconsin.
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 Dec 15, 5:51 PM CST, 5 hours 9 minutes earlier.
Area Forecast Discussion National Weather Service Green Bay WI 551 PM CST Wed Dec 15 2021 Updated aviation portion for 00Z TAF issuance .SHORT TERM...Tonight and Thursday Issued at 251 PM CST Wed Dec 15 2021 Decided to extend the Dense Fog Advisory until 9pm for the snow covered portion of the forecast area as visibility is still only a few hundred feet in most areas. The fog should mix out as a line of convection moves across the area during the middle and late evening hours ahead of a strong cold front. The line of showers and thunderstorms is likely to produce wind gusts of 60 mph or more. The winds aloft are so strong that it is not out of the question for some winds to exceed 70 mph. After the front moves through strong gradient winds are likely to produce wind gusts of 40 to 60 mph for several hours late tonight and early Thursday. Utilities may have some significant tree and power line damage in some areas. The winds will slowly diminish Thursday, but will still gust to 40 or 50 mph during the morning hours. Temperatures will rise this evening to record levels in many areas this evening, then fall later tonight and during the day Thursday. .LONG TERM...Thursday Night Through Wednesday Issued at 251 PM CST Wed Dec 15 2021 After all the action occurring in the short term forecast, the extended period is by contrast a much quieter period. The extended period will start off with a period of dry conditions Friday before another weak shortwave moves across the region Saturday morning. With ongoing CAA during this period, colder and dry air will lack significant moisture and lift to produce much more than a quick dusting of snow. High temperatures to start the weekend will be mainly in the 20s Friday, and teens to lower 20s on Saturday. Surface high pressure returns for Saturday night through Sunday, and will linger on through the remainder of the period. There is a clipper system that will cross north of us around the middle of next week, but no precipitation is expected in Wisconsin at this time. Therefore, most of the extended forecast is dry, excepting Saturday. Temperatures will remain fairly close to normal, ranging from the lower 20s to lower 30s through the extended. && .AVIATION...for 00Z TAF Issuance Issued at 546 PM CST Wed Dec 15 2021 Challenging conditions for flying are expected through Thursday. IFR ceilings and/or visibilities and areas of dense fog are expected through the evening hours, with low level wind shear expected as evidenced by KGRB VWP. Scattered showers and thunderstorms will move across the area this evening ahead of a cold front. The winds aloft are exceptionally strong, so even shower activity could produce surface wind gusts of 50 knots or more. Strong southwest sustained winds of 20 to 30 knots with gusts to 50 knots are expected behind the front later tonight through midday Thursday. && .GRB WATCHES/WARNINGS/ADVISORIES... High Wind Warning from 9 PM this evening to 9 AM CST Thursday for WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074. Dense Fog Advisory until 9 PM CST this evening for WIZ005- 010>013-018>022-030-031-035-036-040-050-073-074. && SHORT TERM.....RDM LONG TERM......Uhlmann AVIATION.......Kurimski
Hazardous Weather Outlook National Weather Service Green Bay WI 256 PM CST Wed Dec 15 2021 WIZ005-010>013-018>022-030-031-035>040-045-048>050-073-074-162100- 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- 256 PM CST Wed Dec 15 2021 This Hazardous Weather Outlook is for north-central and northeast Wisconsin. .DAY ONE...Tonight Dense fog will result in hazardous travel conditions through the evening hours, especially for areas that still have snow on the ground in central and northern Wisconsin. An approaching cold front will produce a line of showers and thunderstorms this evening. Some could produce damaging wind gusts of 60 to 70 mph. There is a small chance of tornadoes, especially in central Wisconsin. After the thunderstorms go by, an intensifying low pressure system will produce strong winds after midnight, with gusts of 50 to 70 mph. Damage to trees and powerlines will occur, likely resulting in power outages over parts of the area. Ice shoves are possible on the eastern shore of Lake Winnebago. .DAYS TWO THROUGH SEVEN...Thursday through Wednesday Strong gusty west winds will continue on Thursday, with the highest gusts occurring early in the day. Travel will remain hazardous for high profile vehicles, especially on north to south oriented roads. .SPOTTER INFORMATION STATEMENT... Spotters are requested to relay peak wind gusts and any reports of damage to the National Weather Service in Green Bay. LMZ521-522-541>543-162100- The Bay of Green Bay south of a line from Cedar River MI to Rock Island Passage-Lake Michigan from Washington Island to Sheboygan- 256 PM CST Wed Dec 15 2021 This Hazardous Weather Outlook is for portions of northwest Lake Michigan and the waters of Green Bay. .DAY ONE...Tonight A storm warning is in effect after 9 pm for southwest storm force gusts to near 60 knots. .DAYS TWO THROUGH SEVEN...Thursday through Wednesday Southwest to west storm force gusts to near 60 knots are expected Thursday morning, easing to gale force gusts in the afternoon. A Storm Warning remains in effect through noon Thursday. RDM/Uhlmann
PRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1028 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1023 PM TSTM WND GST WAUSAU 44.96N 89.63W
12/15/2021 M56 MPH MARATHON WI ASOS
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1035 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1028 PM TSTM WND GST STEVENS POINT 44.51N 89.56W
12/15/2021 M46 MPH PORTAGE WI TRAINED SPOTTER
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1040 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1037 PM TSTM WND GST STEVENS POINT 44.51N 89.56W
12/15/2021 M52 MPH PORTAGE WI TRAINED SPOTTER
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1048 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1037 PM TSTM WND GST STEVENS POINT 44.51N 89.56W
12/15/2021 M39 MPH PORTAGE WI AWOS
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1053 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1046 PM TSTM WND GST RHINELANDER 45.63N 89.41W
12/15/2021 M43 MPH ONEIDA WI ASOS
&&
ECKBERGPRELIMINARY LOCAL STORM REPORT
NATIONAL WEATHER SERVICE GREEN BAY WI
1058 PM CST WED DEC 15 2021
..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON...
..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE....
..REMARKS..
1050 PM TSTM WND DMG 1 E ANTIGO 45.15N 89.13W
12/15/2021 LANGLADE WI PUBLIC
REPORT FROM MPING.
&&The national radar mosaic for the moment the first event began.
11 high wind. Local standard time, as filed.
High winds downed trees and power lines in Winnebago County. Peak winds of 58 mph were measured at the Oshkosh airport.
High winds downed trees and power lines in Calumet County. Peak winds of 71 mph were measured in Forest Junction.
High winds downed trees and power lines in Wood County. Peak winds of 74 mph were measured at the Marshfield airport.
High winds downed trees and power lines in Outagamie County. Several power poles were downed by high winds near Mackville.
High winds downed trees and power lines in Brown County. Peak winds of 60 mph were measured at the Green Bay airport.
High winds downed trees and power lines in Oneida County. Peak winds of 76 mph were measured at the Rhinelander airport.
High winds downed trees and power lines in Langlade County. Peak winds of 53 mph were measured at the Antigo airport with sustained winds over 40 mph for over an hour.
High winds downed trees and power lines in northern Marinette County. Peak winds of 58 mph were measured in Pembine.
High winds downed trees and power lines in Marathon County. Peak winds of 62 mph were measured at the Wausau airport.
High winds downed trees and power lines in Vilas County. Disasters were declared in the towns of Lincoln and Phelps.
High winds downed trees and power lines in Door County. Peak winds of 66 mph were measured at Washington Island.
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, December 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: 989650, 989653, 989638, 989640, 989641, 989628, 989632, 989634, 989635, 991519, 989647.