3/25/10 DISC: AL

[David Reimer]

An interesting situation in central Alabama this evening with at least one confirmed tornado in the Alabaster area. It looks like it caught most everyone off guard as it took a little longer then normal to get a warning out, but that can be discussed in a separate thread. This tornado was unique as it produced the tornado only 10 miles from the radar, so there should be a pretty good data set. The couplet first popped up on a low topped storm about 6:45 PM. It was obvious by the :51 scan that it was not bad data as most tilts had an obvious circulation. It wasnt strong by any means but as it was only 5-10 miles from the radar it was pretty obvious that something was going on. Not much more to know until the survey comes in, but BMX confirmed the tornado about 45 minutes after it occurred with NWS Mets on site.

Anyway, I've posted a couple level 2 frames along with the Tornado Warning/Statements over on the website at www.texasstormchasers.com

- David Reimer
www.TexasStormChasers.com

 

[Shane Adams]

Again, the circulation was weak....which IMO is the key. The NWS probably waited until there were more signs of stronger rotation to flip the switch. My grandma can look at radar and see .5 level rotation, but that's as far as her (and most non-degreed observers') skills go. There's far more to radar interpretation than having GR3, no job, and green/red pixals.

 

[Brett Adair]

The couplet from the Alabaster tornado was much more noticeable from the MXX radar site. Our WCM captured this tornado along with myself which is what really prompted the warning. John De Block was on his way home and spotted the rotation and funnel cloud which prompted the warning ONE minute before the debris was evident in the air at the base of the funnel.

BMX was looking for more of a gate-to-gate signal or spotter reports since it was in a very populated neck of the woods. However, as we learned with these low topped animals....the storm can be 5 miles from the radar and the strongest part of the low level circulation is sometimes still not evident. That's why eyes are most important.