Gravity waves due to ducting generated a narrow line of strong wind across Central Minnesota to Eastern Minnesota on the morning of April 19th, 2023. Early that morning a weak system produced precipitation across the region.
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 MPX wrote it up.
Gravity waves due to ducting generated a narrow line of strong wind across Central Minnesota to Eastern Minnesota on the morning of April 19th, 2023. Early that morning a weak system produced precipitation across the region. Upper-Air soundings from NWS Twin Cities detailed a low-level inversion/stable layer at approximately 6,000 feet above the surface with remnant instability from the previous rainfall early that morning. Over the Central Plains, low pressure was developing an associated warm front that extended over Iowa was advancing towards Minnesota. Meanwhile in the upper-levels, a trough was beginning to dig over the Western Dakotas. As these features progress northeastward, remnant low-level forcing would interact with the capped layer and be refracted back towards the ground and creating a line of gusty winds across the surface.
A few isolated reports of strong winds occurred across the northern half of the Twin Cities metro area. In Wright County, Buffalo, MN ASOS station recorded at 48 mph gust just before 9 AM CST. A section of wooden fence was pushed over in a neighborhood located in St. Michael, MN. Farther east in Ramsey County, a few small trees were downed as a result of strong winds in Maplewood, MN.
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 Twin Cities, MN wrote its last area forecast discussion before the first event at Apr 19, 5:25 AM CST, 3 hours 30 minutes earlier.
Area Forecast Discussion...UPDATED National Weather Service Twin Cities/Chanhassen MN 625 AM CDT Wed Apr 19 2023 .DISCUSSION...(Today through Tuesday) Issued at 355 AM CDT Wed Apr 19 2023 KEY MESSAGES: - Multiple rounds of showers and thunderstorms this morning through Thursday - Chance of light snow Thursday night into Friday. - Precipitation amounts of an inch or more over the next 48 hours could aggravate flooding on rivers. A dissipating band of showers and thunderstorms will move northeastwards through central Minnesota and western Wisconsin through the morning, driven by a compact shortwave pivoting ahead of the main trough still off to our west. Despite surface temperatures in the 40s and little or no surface-based instability, isolated wind gusts over 60 mph have been reported overnight with some of these storms over eastern SD & northwestern IA. However weakening trends on radar and the storms moving into an even more marginal environment suggest any damaging winds or hail is very unlikely from the storms this morning. The band of showers and thunderstorms will move east into central Wisconsin by late morning, & then a break in the rain is expected for most of the day until showers and thunderstorms redevelop late this afternoon & evening. Forcing will be stronger with this second wave as the trough deepens & moves overhead, & a supportive atmosphere for all modes of severe weather looks likely to develop in the warm sector of a developing surface low over KS/NE/IA. The general consensus is that the surface low & warm sector will remain south of our area, probably nosing up into northern Iowa, which would limit the severe risk for southern Minnesota. Elevated showers and thunderstorms are more likely for our area north of the warm front tonight and the strongest storms could contain some borderline severe hail across southern Minnesota. A few ensemble members do surge the warm front farther north up to I-90 so a more widespread hail/wind/tornado threat can't totally be ruled out, but those probabilities are certainly much higher across northern Iowa. Rain showers will continue overnight into Thursday morning as the trough develops into an upper level low & spins overhead. Temperatures look to stay warm enough overnight & during the morning to limit any wintry precipitation to northern Minnesota. The rain showers should come to an end Thursday afternoon as a dry slot develops over the region, while wintry precipitation continues across northern MN & ND. Cyclonic flow from the warp-around region of the system moves overhead on Friday, generating scattered light rain/snow showers during the day. Rainfall amounts over the next 48 hours are hard to forecast for an exact location, since each wave of showers and thunderstorms will be rather sporadic in coverage. The heaviest precipitation is forecast with the waves of showers and thunderstorms this morning & then late this afternoon through tonight. Rainfall amounts generally increase as you head eastwards into Wisconsin, amounts of 1-1.5" look most likely across eastern MN & western Wisconsin while only a quarter inch or so is possible across western Wisconsin. Creeks, streams, & mainstem rivers are already flooding & remain very sensitive to any additional precipitation, so monitor hydrological forecasts and flood statements to see how crest forecasts may change. Drier weather is forecast over the weekend into early next week, with temperatures gradually warming back towards normal values for late April. The next chance for precipitation comes midweek. && .AVIATION...(For the 12Z TAFS through 12Z Thursday morning) Issued at 625 AM CDT Wed Apr 19 2023 Widespread rain has enveloped the area early this morning, but it shouldn't last long. Most of it will exit to the east between 14-16Z. Cigs will drop following the rain, likely to low end MVFR levels, but some IFR cigs are also possible. Additional showers will develop this evening and could contain some TS this evening. KMSP...Expecting showers to continue through about 14Z, then dry through the afternoon. Cigs should remain MVFR, but will likely drop to IFR this evening as the next round of showers begins to arrive. /OUTLOOK FOR KMSP/ THU...MVFR/IFR with -SHRA likely. Wind ESE 10-15 kts becoming W 15-20G30 kts. FRI...MVFR with -SHRASN likely. Wind SW 10-20 kts. SAT...MVFR with -SHRASN likely. Wind NW 10-20 kts. && .MPX WATCHES/WARNINGS/ADVISORIES... MN...None. WI...None. && DISCUSSION...ETA AVIATION...Borghoff
Hazardous Weather Outlook National Weather Service Twin Cities/Chanhassen MN 347 AM CDT Wed Apr 19 2023 MNZ041>045-047>070-073>078-082>085-091>093-WIZ014>016-023>028- 200900- Douglas-Todd-Morrison-Mille Lacs-Kanabec-Stevens-Pope-Stearns- Benton-Sherburne-Isanti-Chisago-Lac Qui Parle-Swift-Chippewa- Kandiyohi-Meeker-Wright-Hennepin-Anoka-Ramsey-Washington- Yellow Medicine-Renville-McLeod-Sibley-Carver-Scott-Dakota- Redwood-Brown-Nicollet-Le Sueur-Rice-Goodhue-Watonwan-Blue Earth- Waseca-Steele-Martin-Faribault-Freeborn-Polk-Barron-Rusk- St. Croix-Pierce-Dunn-Pepin-Eau Claire- 347 AM CDT Wed Apr 19 2023 This Hazardous Weather Outlook is for portions of central and southern Minnesota, and west central Wisconsin. .DAY ONE...Today and Tonight. Thunderstorms capable of isolated large hail and damaging wind are possible this morning & tonight across southern Minnesota. River flooding is ongoing from the recent snow melt. See flood statements for additional details on individual rivers. .DAYS TWO THROUGH SEVEN...Thursday through Tuesday. River flooding continues into next week. Tributary and main stem river flooding is ongoing and levels of many of the main stem rivers are continuing to rise. .SPOTTER INFORMATION STATEMENT... SKYWARN spotter activation will not be needed.
Special Weather Statement
National Weather Service Twin Cities/Chanhassen MN
407 AM CDT Wed Apr 19 2023
MNZ082-091-092-191030-
Watonwan MN-Martin MN-Faribault MN-
407 AM CDT Wed Apr 19 2023
...An area of strong winds will impact portions of Faribault, Martin
and Watonwan Counties through 530 AM CDT...
At 403 AM CDT, an area of strong winds was tracking northeast over
northwest and north central Iowa, moving northeast at 45 mph.
Although sporadic, some gusts have ranged from 60 to 70 mph.
HAZARD...Wind gusts of 50 to 55 mph. Higher gusts are possible.
SOURCE...Radar indicated.
IMPACT...Gusty winds could knock down tree limbs and blow around
unsecured objects.
Locations impacted include...
Fairmont, St. James, Blue Earth, Wells, Madelia, Winnebago, Sherburn,
Truman, Trimont, Minnesota Lake, Welcome and Elmore.
This includes the following highways...
Interstate 90 between mile markers 82 and 142.
U.S. Highway 169 between mile markers 1 and 25.
PRECAUTIONARY/PREPAREDNESS ACTIONS...
If outdoors, consider seeking shelter inside a building.
&&
LAT...LON 4350 9485 4411 9486 4411 9437 4385 9436
4384 9365 4350 9365
TIME...MOT...LOC 0903Z 214DEG 39KT 4339 9478
MAX HAIL SIZE...0.00 IN
MAX WIND GUST...55 MPH
BorghoffThe national radar mosaic for the moment the first event began.
2 strong wind. Local standard time, as filed.
Strong easterly winds were recorded near St. Michael, MN area where parts of a fence were blown over. Buffalo, MN AWOS station recorded a 48 mph wind gust at 8:55 am.
A few small fallen trees were reported as a result of the strong wind gust near Maplewood, MN. KANE ASOS station recorded winds of 45 mph at 8:47 AM. KSTP ASOS recorded a 30 mph gust at 9:13 AM.
After NWS Directive 10-1605, the rules offices file Storm Data by.
Every storm in Minnesota in 2023Every state in 2023This day in weather historyWarnings in Minnesota, April 2023
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: 1090715, 1090962.