Can somebody explain what is happening over Houston

[PTPatrick]

Okay...I know the the low pressure system has moved in over lousiana...but if you look at satellite and radar it is almost as if a TS has moved ashore in Houston. The radar looks striking similar to Allison. I know that this is not a true tropical feature, but could somebody please explain from a meteorological standpoint, what is going on there.

[Yankeegirl]

I know...I just looked at the doppler... Doesnt it look odd?? I live out by Katy.. We havent gotten too much rain as of yet, but its been raining on and off... some thunder sometimes too... That doppler sure looks odd though!




Lisa

[Hurricanehink]

Ooh, that does look cool. That's ashame, too, because they really don't need the rain.

[vbhoutex]

There is an Upper Level Low sitting right on top of Houston. That is what is causing the spin you see. We are at the center of circulation of the ULL.

This discussion probably belongs in the US Weather forum, but I will leave it here for now. If another staff member feels it needs to be moved have at it.

[stormie_skies]

Local mets and TWC were saying that the spin is due to an upper level low that is interacting with the tropical disturbance to our east and sucking up some of its moisture, if I understood them correctly. Either way, looks like we are in for a wet couple of days. And you're right ~ that radar is downright weird!

http://www.srh.noaa.gov/radar/loop/DS.p19r0/si.khgx.shtml

[GalvestonDuck]

And for amateurs like me -- lows circulate counter-clockwise and highs circulate clockwise.

So, just like Allison, it looks like it's spinning around and around. I remember watching that for what seemed like days because she just sat over the area and never moved. Rain came in cycles down here on the island and you could watch it circle up, around, and back down over us.

[elw]

Local mets and TWC were saying that the spin is due to an upper level low that is interacting with the tropical disturbance to our east and sucking up some of its moisture, if I understood them correctly. Either way, looks like we are in for a wet couple of days. And you're right ~ that radar is downright weird!

http://www.srh.noaa.gov/radar/loop/DS.p19r0/si.khgx.shtml

That's exactly right!



Notice the upper low is located right over Southeast Texas.

[Stormsfury]

And the same upper low that I said would develop 3 days ago based on a unaminous agreement by all the globals, ensembles, and mesoscale models ...

SF

[elw]

And the same upper low that I said would develop 3 days ago based on a unaminous agreement by all the globals, ensembles, and mesoscale models ...

SF

Here it is on today's 12z ETA initial, it's centered almost right over the Huston-Galveston area.



Could also be some isolated severe weather underneath the upper low, with pocket of 500mb temps of -10 to -12 C, helping to steepen mid-level lapse rates, and low LCL heights.

http://198.63.55.43/CONUS_ETA_LCL_GPH_00HR.gif