Mega Downpour..

[Aquawind]

SIOUX FALLS, South Dakota (AP) -- A two-hour storm dumped nearly 8 inches of rain on southwest Sioux Falls early Wednesday, flooding streets and basements and spilling the Big Sioux River into parks and bike trails.

"The ground is totally saturated," said Lyle Johnson, Sioux Falls' director of public works.

City officials said it was the worst flooding in Sioux Falls in 10 years.

While the southwest part of the city got 7.79 inches, Sioux Falls Regional Airport on the city's north side measured 3.54 inches, said National Weather Service meteorologist Todd Heitkamp.

Several parks were closed along the river, and water was rising nearly to the bottom of some bridges in the Sioux Falls area, authorities said.

The downpour washed out a parking lot in eastern Sioux Falls, creating a jagged gully with a stream gushing through it.

City and Minnehaha County officials were still assessing damage but said water had collapsed at least one basement and flooded many others.

[Stormsfury]

Whew ... I can relate to that on two occasions (actually more, but I'll use two examples ...)

Today ... a small line of thunderstorms moving VERY SLOWLY - less than 5 miles an hour set up shop over this location and dumped 2.97", most of that fell in about an hour's time...which caused minor flooding across Dorchester, Trolley, and Ladson Roads today ... On Trolley Rd, the road was closed along a mile stretch, with 6 cars on the road submerged under 2 to 3 feet of water (tow trucks pulling them out).

In 1999, a nearly stationary thunderstorm over the area dumped a little over 9" of rain in just 3 hours time, with some redevelopment occurring a little south and east of the area dumping 4"-6" in those locations ... massive flooding problems ...

SF

[Dan]

The night Hurricane Floyd flooded out Eastern North Carolina, there was a thunderstorm that developed over away from all that, back in Rutherford County NC (Western North Carolina), which dumped 11 inches of rain in 3 hours at Chimney Rock Park, and flooded many creekside stores and houses. It took 6 months for some areas to fully recover from the damage. Most of America's eyes though were focused on something more dangerous that night.

[KatDaddy]

The most rainfall I ever experienced was 22.50" over 24 hours during TS Claudette 1979. Not far to my SW Alvin picked up 43" in 24 hours.

TS Allison was another tropical deluge but not nears as disasterous as TS Claudette in my area.

The big difference between the two was the location of the rains. Allison was Harris, Montgomery, Libery, NE Brazoria, N Galveston County event.

TS Claudette was mainly Matagorda, Brazoria, Galveston, SE Harris, and S Liberty County event. Areas S of Houston were hit very hard.

[Aquawind]

I always cringe when I see echos training on the radar..Funny thing is usually it is usualy only associated with heavy rain and lightening..not hail or tornados.. It seems like sucha violent process going from basicaly clear skies..to imeadiate downpour and then staying over the same area..like lighting a match and waiting for it to burn out..I guess that training is the culpret itself the winds are aligned and not mixing enough for violence..perfect for precip though..

It's when the line stays in place and yet the Cells are popping and moving along at a good clip that amaze me.. I vision a hoover vacuum at the starting point sucking all the LL air into one little spot and going straight up..