Flash Flood, Sauk
- When
- May 17, 6:15 PM CST to 7:30 PM CST
- Where
- Sauk County, Baraboo
- Property damage
- $10,000
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 43.427, -89.948 (the zone’s center; the record gives no point)
Flash Flooding and Hail in Wisconsin, May 17 to 18, 2000
The second round of adverse weather on the 17th started off as a large hail and damaging wind event in Sauk County, but quickly changed to a heavy rain and flash flooding event as individual cells became more numerous and clusters moved east/southeast. Training echos were common which led to flash flooding.
Where it happened
Every event with a place to put it; 9 filed by county or forecast zone are drawn at its center, in a lighter ring. Tap one for its entry below.
- Tornadoes
- Tropical storms and surge
- Floods
- Wind
- Hail
- Winter weather
- Heat and drought
- Cold
- Fire, smoke and dust
- Marine and coastal
- Other
The toll
- Deaths
- 0
- Injuries
- 0
- Property damage
- $558,000
- Crop damage
- None recorded
- Events
- 13
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.
What happened
The episode as NWS MKX wrote it up.
The second round of adverse weather on the 17th started off as a large hail and damaging wind event in Sauk County, but quickly changed to a heavy rain and flash flooding event as individual cells became more numerous and clusters moved east/southeast. Training echos were common which led to flash flooding. Damaging straight-line winds toppled large trees in Sauk and Columbia Counties while hail up to 1.00 inch in diameter also fell. However, from then on the storms became prolific rain-producers: Watertown (Jefferson Co.) had 2.52 inches of rain in 1.5 hours, Grafton (Ozaukee Co.) had 1.75 inches in one hour. WSR-88D Doppler radar estimated a total of 3 to 3.8 inches fell from southeast of Portage (Columbia Co.) to the Watertown area from 1800 to 2030CST on the 17th, and 2 to 3 inches east into northern Milwaukee County. About 2000 customers in southeast Wisconsin lost electrical power due to either downed power lines or lightning strikes.Throughout the areas that experienced flash flooding it was noted that water levels rose to 1 to 3 feet over many roads (urban and rural) leading to numerous reports of gravel shoulder washouts, blocked roads, stranded/damaged vehicles, flooded basements, and clogged sewers. In Brown Deer (Milwaukee Co.) water was up to 4 feet deep on some roads and there were reports of mudslides. Fortunately, there were no injuries or deaths, possibly due to timely warnings.For the calendar day of May 17th, Milwaukee Mitchell Field (Milwaukee Co.) picked up 1.70 inches of rain, breaking the old record of 1.20 set back in 1889. Madison's Truax Field (Dane Co.) set a new daily record of 2.58 inches. On the weather map the Colorado low had moved to eastern Nebraska by the end of the 17th while the west-east frontal boundary had moved north to the Wisconsin/Illinois border. Southern Wisconsin during the time of the flooding had northeast winds and temperatures around 60.
The radar
The national radar mosaic for the moment the first event began.
Event by event
9 flash flood, 2 thunderstorm wind, 2 hail. Local standard time, as filed.
Thunderstorm Wind, Sauk
- When
- May 17, 6:22 PM CST
- Where
- Sauk County, Baraboo
- Measured
- 52 kt (60 mph)
- Property damage
- $2,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.467, -89.733
Thunderstorm Wind, Columbia
- When
- May 17, 6:35 PM CST to 6:45 PM CST
- Where
- Columbia County, 3 mi W of Portage
- Property damage
- $1,000
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 43.550, -89.517
Flash Flood, Dodge
- When
- May 17, 7:00 PM CST to 8:00 PM CST
- Where
- Dodge County, 1 mi W of Danville
- Property damage
- $20,000
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 43.416, -88.707 (the zone’s center; the record gives no point)
Hail, Dodge
- When
- May 17, 7:10 PM CST
- Where
- Dodge County, Randolph
- Measured
- 0.75 in hail
- Reported by
- NEWSPAPER
- Coordinates
- 43.533, -89.000
Hail, Kenosha
- When
- May 17, 8:10 PM CST
- Where
- Kenosha County, Somers
- Measured
- 1 in hail
- Reported by
- LAW ENFORCEMENT
- Coordinates
- 42.650, -87.900
Flash Flood, Columbia
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Columbia County, South Portion
- Property damage
- $50,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.467, -89.334 (the zone’s center; the record gives no point)
Flash Flood, Dodge
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Dodge County, Juneau
- Property damage
- $50,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.416, -88.707 (the zone’s center; the record gives no point)
Flash Flood, Washington
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Washington County, South Portion
- Property damage
- $75,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.369, -88.231 (the zone’s center; the record gives no point)
Flash Flood, Ozaukee
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Ozaukee County, Mequon
- Property damage
- $75,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.403, -87.891 (the zone’s center; the record gives no point)
Flash Flood, Waukesha
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Waukesha County, Mapleton
- Property damage
- $50,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.018, -88.304 (the zone’s center; the record gives no point)
Flash Flood, Milwaukee
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Milwaukee County, North Portion
- Property damage
- $200,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.022, -87.929 (the zone’s center; the record gives no point)
Flash Flood, Jefferson
- When
- May 17, 8:15 PM CST to May 18, 1:00 AM CST
- Where
- Jefferson County, Watertown
- Property damage
- $25,000
- Reported by
- AMATEUR RADIO
- Coordinates
- 43.021, -88.776 (the zone’s center; the record gives no point)
What these are
- Flash Flood
- Flooding that begins within six hours of the rain that causes it, or of a dam or levee failure or ice jam release, often with deadly speed.
- Thunderstorm Wind
- Winds from a thunderstorm of 50 knots (58 mph) or more, or lower winds that caused damage or casualties. Measured gusts are marked MG, estimated EG.
- Hail
- Hail three-quarters of an inch or larger, or smaller hail that caused damage, filed with the largest stone measured.
After NWS Directive 10-1605, the rules offices file Storm Data by.
The same day elsewhere
- Hail in Iowa, May 17, 2000
- Hail in Minnesota, May 17, 2000
- Hail and Damaging Wind in South Dakota, May 17, 2000
- Tornadoes and Hail in Colorado, May 17, 2000
- Hail in Wisconsin, May 17, 2000
- Hail in Iowa, May 17, 2000
- Hail in Kansas, May 17, 2000
- Hail and Damaging Winds in Nebraska, May 17 to 18, 2000
- Hail in Minnesota, May 17, 2000
- Hail and Damaging Winds in South Dakota, May 17, 2000
- Hail and Damaging Winds in South Dakota, May 17, 2000
- Damaging Winds in Pennsylvania, May 17, 2000
More
Every storm in Wisconsin in 2000Every state in 2000This day in weather historyWarnings in Wisconsin, May 2000
Sources
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: 5144820, 5145177, 5143923, 5143925, 5143924, 5143933, 5143926, 5143927, 5143928, 5143929, 5143930, 5143931, 5143932.