The Flash Floods This Summer Have Been Incredible

Flooding near Islip, Long Island Wednesday.  

As I write this during my latest visit to Yankton, South Dakota, it's raining like CRAZY one state above me, up in North Dakota.    

More than five inches of rain have fallen in some areas, and it's still pouring up there. It's yet another example of a summer that has had some pretty incredible rain events.

Last week takes the cake. Especially on Long Island, where Islip had 13.57 inches of rain in one day.

Of that, 9.71 inches fell in two hours. To put that in perspective, Islip normally gets less rain than that over the course of two entire Augusts.

According to weather historian Christopher Burt, the narrow corridor of incredible rains on the East Coast is almost unprecedented. Certainly, the Islip rain was the heaviest 24 hour rainfall in New York State History.

Other areas of the East got clobbered, too. Green Haven, Maryland got 10.32 inches of rain, and Scarborough, Maine got 6.59 inches.

The rainfall rates were the big story, because in many areas, like Islip, the bulk of the rain came in two hours, three at the most. For instance, in Portland, Maine, 4.21 inches of rain fell in just two hours.

In the Northeast, rainfall in the amounts that happened in one day last week come during tropical storms or hurricanes. And it is hurricane season. However, this incredible rain had nothing to do with any tropical storm. Tropical air, yes, but not a tropical storm.

Super wet air from the tropics went up and over a weak weather front draped along the East Coast, At the points twhere the soggy, warm air had to rise over the cooler air on the other side of the weather front, the air rose, the moisture condensed, and down came the torrents.

It was also interesting to see how narrow the area of flash flooding and heavy rain was. That actually happens quite a bit in flash flood situations. One town gets blasted by the flood, and one or two towns over, there's not much to talk about.

In this case, 40 miles west of Islip, an unremarkable. 0.78 inches of rain fell during the storm. About 40 miles to the east of Islip, they only got maybe a half inch of rain. Yawn.

Damage patterns were interesting, too. On Long Island, most of the flooding was on highways and streets, and most of the damage was to cars, and some basements.

A similar torrential storm of 4.57 inches hit the Detroit area and other parts of southeastern Michigan the day before the East Coast got nailed. In the Detroit area, damage estimates are up to $1.2 billion and about 18,000 houses had flood damage, says Christopher Burt.

It all depends upon the topography, where the streams are and where the parking lots, streets and roofs prevent water from soaking into the ground.

Of course, in these extreme rain events, everybody asks if global warming has anything to do with this. Like Burt, I'm turning to Dr. Marshall Shepard, who has a great explaination about this.

Basically, he's reluctant to attribute one weather event like this to climate change, but climate change does make extreme rainfall events more likely, so we'll be seeing more of these big local flash floods.

Shepard also points out that in recent decades, a lot more urbanization with its giant parking lots, huge roofs, sprawling suburban tracts and highways mean there's too much concrete and asphalt out there to allow rain runoff to soak into the ground. Instead it pours off the parking lots and roofs and causes worse flooding.

Interestingly, social problems might have made the Detroit flooding worse, according to CBS Detroit.  The cash-strapped region had antiquated pumping stations to remove water from freeways, and thieves stealing copper pipes rom pumping stations of course made them unable to function.

So, we'll keep watching these local, devastating flash floods keep popping up worldwide. Today it's North Dakota. Who else will get washed away tomorrow.?

Flooding Socks U.S. East Coast; Threat Continues Today

A stranded motorist in Detroit Monday. 

As expected, areas of heavy rain hit parts of the nation's East as another slow moving, strangely strong (for summer) storm system lumbers through.

The Detroit, Michigan area got the worst of it on Monday with its second wettest day on record, and widespread flooding in that region.

Two people died in Detroit area during the flood, including a 100 year old woman found in her flooded basement.

Dozens of people were rescued from cars, most of the region's Interstate highways flooded and some motorists were trapped in their cars for up to 18 hours, hemmed in by flash flooding ahead of and behind them.

There was even more flooding Tuesday, especially in the Washington DC/Baltimore area.  It was hit and miss, as always. Washington DC proper only got an inch or two of rain, while the Baltimore area and nearby areas were swamped with four to eight inches of rain.

The Baltimore-Washington airport was flooded, with a lot of the cars in the long term parking lot submerged. Plenty of travelers are going to get an unpleasant surprise when they return home.

The flooding spread northward into New Jersey last night and early this morning, rainfall rates that briefly reached  up to three inches per hour were hitting parts of Long Island and Connecticut, where flash flooding was ongoing there.  

Flooded parking lots at the Baltimore-Washington
airport on Tuesday.  

The storm is actually moving a bit slower than many forecasters thought, so in some areas the rain lingered longer than hoped, making the rainfall totals go way up.

Up here in Vermont, it scarcely rained overnight Tuesday and early Wednesday, despite forecasts of heavy rain after midnight.

That's because the storm is moving slower than expected, and the rain lingered in New York State instead of blasting into Vermont.

But it'll come in today, and it will rain hard at times today in Vermont, and other areas of New England.

In addition to the flooding now going on in Connecticut and Long Island, flash flood watches are up for all of southern New England and New Hampshire, the southeastern third of Vermont and in southeastern New York State.

In southern New England, torrential areas of rain and thunderstorms are the threat. In New Hampshire and Vermont, it's very wet winds from the southeast rising up the eastern slopes of the mountains to wring out possibly enough rain to cause local flash floods.

Further north in northern New York and Vermont, it hasn't been as rainy lately as others sections of the Northeast, so the ground can absorb more of the expected moderate to heavy rain. Plus, precipitation won't come down as hard there today as it will in southern New England.

Elsewhere in the nation, flash flood watches are also up for Utah and parts of surrounding states due to possible torrential thunderstorms with the seasonal monsoon.

For the nation as a whole, this summer has really been the season of the flood. They keep hitting repeatedly, and (almost) everywhere.

To drive home the point of how dangerous flash floods can be, we have two videos. The first shows a flash flood busting down the doors of a hospital in Kearney, Nebraska last week.

The second video shows a complete moron in Colorado recently driving into flood water, with the inevitable result. Jerk. Turn around, don't drown. (Love the very end of that video with the idiot opening the car doors)