Does SE Texas 'bust' watches? Why?

[Ed Mahmoud]

I was replying to a post in the SE Texas thread, and hazarded a guess. I have no idea if SPC does post storm analysis on big watch busts, but it just seems to me that no place 'busts' severe watches like SE Texas.

Anybody with knowledge wanna weigh in?

So i am thinking this is like the 2nd or 3rd time this spring that the news channels have hyped up all this severe weather coming this way to only have it bust. I think if they keep doing this people are going to just ignore the warnings. As for me, I am sick off all the hype...So far I am not impressed with the storms.... or lack of....

No, like the last bust this looked quite scary on the forecast model soundings, and SPC doesn't issue PDS watches without a reason, there is just something about SE Texas that seems to bust watches like nowhere else in the US. Maybe proximity to the highlands of Coahuila and Chihuahua, where the capping layer often originates, and where data sampling points are sparse, leads to model underestimation of capping.

Just a guess, but watches bust a lot around here.

[Ed Mahmoud]

This may be part of it, also from SE Texas/SW Louisiana weather thread...

So i am thinking this is like the 2nd or 3rd time this spring that the news channels have hyped up all this severe weather coming this way to only have it bust. I think if they keep doing this people are going to just ignore the warnings. As for me, I am sick off all the hype...So far I am not impressed with the storms.... or lack of....

No, like the last bust this looked quite scary on the forecast model soundings, and SPC doesn't issue PDS watches without a reason, there is just something about SE Texas that seems to bust watches like nowhere else in the US. Maybe proximity to the highlands of Coahuila and Chihuahua, where the capping layer often originates, and where data sampling points are sparse, leads to model underestimation of capping.

Just a guess, but watches bust a lot around here.

There is some truth that -- I think a lot of it has to do with this particular time of year ---

When there is a cap present (often due to our proximity to the Mexican highlands), we depend on heat/insolation to destabilize the atmosphere to that crucial point of 'busting the cap'. The problem with Feb/March systems here in SE Texas is warm dewpoints are advected over still cold shelf waters offshore. This results in a warm "soupy" mix of drizzle/rain for much of the day and the atmosphere just doesn't get as unstable as it should.

Points further west, where the air comes in a different trajectory and not straight off the Gulf (such as the SC Texas plains), there is sufficient sun/insolation to heat-up the atmosphere & destabilize it.

Points further east tend to not have the cap to overcome.

That often leaves us caught in the middle: gray, humid, and capped. And by the time the dynamics get here, often the system loses its punch.

As far as anything along I-10, there is nothing there, geographic or otherwise, that "splits" storms or anything like that. If you look at a hi-res rainfall distribution map of the Houston area, there are no donuts anywhere. Any one place can be hit-or-miss in a storm system. Sometimes a location may have several misses before getting dumped on, giving the impression that there is a big hole there, but in the long term, it all averages out.

[wall_cloud]

its probably not as bad as you think, Ed. Most people tend to think their area always misses out on things. Its amazing how many times I hear people tell me how storms fall apart or split right before reaching their houses.

Check out this page: http://www.spc.noaa.gov/climo/online/monthly/

It will show you the different types of severe storm reports depicted graphically for 2007/2008. Granted it doesn't say if it matched up with a watch, but you can see that SE TX gets its fair share of warnings.

Part of it does have to do with the geographic location. The low level moisture can many times leave SE TX "in the grunge" for too long during the day. The abundant cloud cover may preclude the convective temp from being reached and prevent the cap from breaking. South TX and portions of SE TX also see the ELM (elevated mixed layer) play a role. This warm/dry air originating from the higher terrain of Mexico tends to cap off the environment (substantially at times). Corpus Christi is affectionately referred to by some forecasters as "The Land of Wasted CAPE". In the Spring and early Summer, they typically have enormous CAPEs but too much CIN to overcome. Thus, a flat cu field is all you may see. This is true as you approach the Houston area as well, although not as noticeable. This makes convective forecasting very difficult. If storms do fire, they have a high probability of becoming severe (generally pulse type). However, it has big bust potential since it depends on greatly diabatic heating. Additionally, mid/upper level wx systems tend to ride farther north in the stronger westerlies so dynamics are not usually as impressive across SE TX, especially as the warm season progresses. Hope that helps.