
Bone dry: Significant sections of the country are facing drought just weeks after the major weather stories were about heavy rains and flooding. What's going on?Courtesy Tomas CastelazoIt was just a few weeks ago we posted incredible pictures and video of devastating floods ripping through Duluth. Now, on a national scale, the weather story is drought. But how bad is it really?
Depends on where you live, but much of the Midwest is falling into drought conditions. It's bad, but not as wide spread as the peak of U.S. drought conditions from 1934. USA Today has an interesting toggle map that allows you compare today's conditions with that record drought.
Even earlier this summer, heavy rains in the Twin Cities had lockmasters along the Mississippi River shutting their gates to control fast-flowing river water. Now downstream, the Mississippi is approaching record-level lows. In some areas around Memphis, the river level has fallen 55 feet from highs set last summer. This CNN website report has interesting satellite images of the newly slimmed Mississippi compared to last year's look.
What do you think of this crazy weather? Share your thoughts here with other Buzz readers.
Alright, it's absolutely beautiful outside today. So what's up with this predicted flooding?
Remember all that rain the week of September 20th? (We got 2-4" here in the Twin Cities, but areas to the southwest of us got as much as 10".)
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Rainfall mapCourtesy National Weather Service
It all had to go somewhere, and that somewhere was the Minnesota River. Why does that affect us here in St. Paul? Take a look at another map:
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St. Paul and the riversCourtesy NASA (Landsat)
Remember: rivers don't necessarily flow south. The reddish line is the Minnesota River. The blue is the Mississippi. And that little blip just north of where the two rivers come together is downtown St. Paul. (The yellow elipse is the area of highest rainfall.)
All that rain is flowing right past us. And it should be impressive. The river's at 15.4' this morning (moderate flood stage), and predicted to crest at 18' (major flood stage) on Saturday morning. But the recent spate of lovely weather means that the flooding should pass quickly--today's prediction has the water level back under 17" by Monday morning.
St. Paul police have closed all the river roads and parks, and are discouraging people from walking down by the river. But you can get a stellar view of everything from outside the Museum on Kellogg Plaza, or inside the museum from the Mississippi River Gallery on level 5.
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Tree crushes fence in South Minneapolis: Southwest corner of Portland Ave. S. and East 43rd Street.Courtesy Mark RyanAn oddball surprise storm caught the city of Minneapolis and other parts of the Twin Cities metro area completely off guard yesterday. ![]()
Clean-up crews were at work less than an hour after the storm: Looking down Portland Avenue toward downtown Minneapolis.Courtesy Mark RyanThe National Weather Center was ambushed as well, and no warning of the tempest was issued. ![]()
Wind-strewn trash bins litter Minneapolis alley.Courtesy Mark RyanNothing's been officially confirmed but Minneapolis residents reported sighting cloud rotation, tornadoes, and hearing the roar of wind as a storm swept through downtown and South Minneapolis. ![]()
Storm-damaged house and trees in South Minneapolis: Northwest corner of Portland Avenue South and East 43rd Street in Minneapolis.Courtesy Mark RyanHundreds of the city's trees were knocked down by the storm. I was at the Science Museum for a meeting when the warning sirens sounded so on the way home I drove into the affected area to see for myself. ![]()
Crushed car in South MinneapolisCourtesy Mark RyanI just happened to have a pocket camera with me (I just bought it over the weekend) so I took some photos of the damage in one small area of South Minneapolis near the intersection of Portland Avenue South and East 43rd Street (I used to live near the neighborhood). Because the storm came on without any warning and much of it under the cover of heavy downpour, the weather service's usual storm spotters weren't in place to report on conditions or damage. Investigators are on site today to determine if the culprit was a small tornado (or tornadoes) or straight line winds. The last tornado to go through Minneapolis was back on June 14, 1981. I remember that one well.![]()
Another unfortunate victim of the freak Minneapolis stormCourtesy Mark Ryan
Minneapolis Star Tribune story
Associated Press story
More about tornadoes on Weather Wiz Kids
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It's only a squirt gun: Wait—what am I saying, "only"?Courtesy Wikimedia CommonsGone are the heady days of the devil-may-care Raindrop Kid, and the infamous Morning Dew Gang. (Not to be confused with the morning dugong, which I believe is just an early-rising manitee-like creature.)
Yessir, the iron fisted rule of the rain barons is over, and the good people of Colorado can now legally gather rainwater.
Colorado is thirsty country, and they’ve got some serious laws regarding water rights. The folks who own flowing and standing water have wanted to make sure that no one tapped into their supply—precipitation in this case—and so it has been illegal to, say, put a bucket under your gutters and water your garden with it.
A 2007 study, however, showed that something like 97 percent of falling water in the Denver area never made it anywhere near a stream (it all either evaporated, or was quickly absorbed my plants), and so whoever owned water rights to a stream didn’t have much to complain about.
Taking this into consideration alongside the growing population of the region, and shrinking water supplies, state government decided to allow people to gather and use the water falling on their homes—so long as they have a permit. So if you’re dead set on maintaining that outlaw freedom, I suppose you could always just use a rain barrel without a permit. Yee-haw.
Roger Ledding, former chief of the Minnesota State Patrol, was on WCCO radio this morning, talking about the high number of traffic accidents during today's am rush hour.
No snow, no ice, so what's the problem?
Well, it's been very dry in the Twin Cities lately. A fine spray of oil from cars routinely covers road surfaces. In very dry weather, that oil can build up. When rain begins to fall, it mixes with the oil and the road surface becomes extremely slippery. It can take a few hours for additional rain to break down and wash away the mess.
Also, this morning's wasn't a gentle, soaking rain, but a downpour. That left standing water on roadways. Drivers traveling too fast found themselves hydroplaning--sliding on a thin film of water, unable to stop or steer.
It's been unseasonably warm, for sure, and I wasn't thinking about hazardous driving conditions on my way in to work this morning. But I will be on the way home...
Storm chasers know that puffy cumulus clouds often cause sudden rainstorms, while storms associated with stratus clouds form more slowly. Now physicists at England’s Open University have finally found an explanation.
They propose that neighboring water droplets in a stable stratus cloud don’t crash into each other because they’re all moving at about the same speed. But fast-forming, turbulent cumulous clouds contain water droplets moving at many different speeds. They crash into each other and form larger drops. As the turbulence grows, the drops grow quickly and fall as rain within a few minutes.

Cumulous cloud: These puffy clouds are associated with sudden rainstorms. Scientists are beginning to understand why.
Sun and rain
Ever noticed the bright, moving lines on the bottom of a stream, bathtub, or swimming pool? They’re called caustics, and they’re caused when ripples on the water’s surface focus sunlight. (Caustics form whenever light rays are bent by a curved surface or object and then projected onto another surface.
Caustics have a characteristic shape. Physicists can graph the phenomenon mathematically, and the graph also describes other phenomena, such as particle motion or the movement of raindrops within a cumulus cloud.

Caustics: What do the rippling patterns on the bottom of a swimming pool and cumulous clouds have in common? (Photo by R. Motti)
Atmosphere to outer space
The researchers say their finding won’t have any impact on weather forecasting. But particle collisions in turbulent gases must have been involved in planet formation. Perhaps the same theory can be applied?
If you're at the museum on Saturday afternoon (11/18), the MakeIt team can help you play with caustics. Does bending mylar in a different direction produce a new pattern? Does using a different color flashlight or a brighter or dimmer light affect the design?
You can also play with caustics at home.
Flooding caused by heavy monsoon rains has displaced 66,000 people in northeastern India. No casualties have been reported.
After all the rain we've had recently, parents of toddlers in the Twin Cities area surely have two questions on their minds:
I can't help with the first question.
But the second, that's a topic for Science Buzz!
I always thought that the worms came out of the ground when it rained to avoid being drowned in their burrows. Turns out I was wrong, wrong, wrong.
A series of Straight Dope articles, by Cecil Adams, have enlightened me.
Worm: (Photo by Jiva)
Turns out that the worms are in no danger of drowning. They can actually survive underwater for quite a long time. They are out on the sidewalk after it rains to engage in, um, "amorous activity." For the slimy details, read the Adams' column!
Of course, that's not ALL the worms are doing. They're also trying to move safely to new areas; vulnerable to drying out as they are, they can only do this aboveground at night or after a rain.
My toddler will be blown away by all this. Her explanation is that worms come out because of some altruistic notion that robins are hungry...
For more information about earthworms, check out this JourneyNorth Q&A page.
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