VERY strange weather behavior. Anyone know how this works?

[dbhost]

On my trip to work today, I went through a weather experience unlike anything I have ever seen before... I am sure we have all been through sudden squalls and driven through the edge of a storm, but let me explain this one...

I drive about 7 miles from home to the office, across a bridge that crosses Clear Lake, which is a tributary of sorts off of Galveston Bay.

The drive from home started out typical end of May, hot, humid, and partly cloudy. Just light fluffy stuff, like high fog, nothing likely to cause rain, until I got to the bridge,

There was ONE cloud, and not a particularly big one, that was dead black, and dumping rain, intensely, directly over the bridge. The rain started and ended at the respective ends of the bridge, almost like the highway department was trying to water down this one bridge and nothing else...

Anyone have any idea how this could take place? The difference between clouds right up against each other was extreme, it was like this 200yd diameter spot of intensity. Just so strange...

[twistsol]

This is just a guess, but it may be the opposite of lake effect snow where warm wet air from the not yet frozen great lakes moves over land, cools off and dumps the snow. It is my guess that the water temperature cooled the air enough to cause precipitation.

[dbhost]

This is just a guess, but it may be the opposite of lake effect snow where warm wet air from the not yet frozen great lakes moves over land, cools off and dumps the snow. It is my guess that the water temperature cooled the air enough to cause precipitation.

An intriguing thought, the clouds weren't super high, and the one that was dumping was directly over the bridge. I would assume the bridge itself, being a large concrete and steel structure was letting off a good amount more heat than the surrounding lake and swampy areas close to the lake...

So in a way, I can see that, extra energy giving it that push. Just odd that I have never seen anything like it before... So very localized it was kind of strange is all...

[leehljp]

Well, I read a book on Texas once and it talked about that kind of selective rain!

[Carlos]

Water causes interesting disturbances as air crosses it. I live close to a lake that often has a rain line right down the middle. I used to have a boat there, so I was there a lot. You could see the line. Air would come across the lake in one direction, and hit the water, causing a defined effect. It was pretty cool.

[Jim Frye]

Not that unusual. We see squalls around here like that quite a lot. My dad used to tell a story about being at sea in a supply convoy in the Pacific during WWII and having one ship being drenched and nearly obscured by rain and a ship along side of it in total sunshine. When I was in the Air Force during the Vietnam era, we were traveling home for Christmas leave from my base in southern Illinois. We were on I-75 and ran into a snow squall. The pavement was totally dry and there was a line of snow across the road that was about 3" deep. It looked like the highway had been masked off. Within a couple of car lengths ('68 VW Beetle), the snow was over 5" deep. It got worse the farther east we went, but the bug was nothing but traction in what turned out to be real snow storm.

[dbhost]

I've seen it where the squalls are bigger, maybe as narrow, but longer, this literally looked like a 100 yard circle of HARD rain, and everything else was peachy keen... But yeah, I get the squall thing, those typically even if only 100 yards deep, might be a mile or two wide from what I have seen, almost never see them circular like this. Almost like a perfect cylinder of rain...

[durango dude]

Putting on my tin foil hat. ...

[durango dude]

Putting on my tin foil hat. ...