Are tornadoes possible with Occluded fronts?

[DNewman]

Hey everyone. I have a challenging subject that I'm doing research over ,talking about tornadic & severe storms associated with occluded fronts (whether cold occcluded or warm occluded). Can tornado events occur along and ahead of occluded fronts? I know there's one possible event back in north Tx in December of 2006, that was with an occluded front, but details are somewhat unclear.
Can anyone recall tornadic and/or severe weather episodes/outbreaks associated with occluded fronts?

 

[Dan Robinson]

Yes - the cold core tornado setup often involves an occluded frontal boundary.

http://journals.ametsoc.org/doi/pdf/10.1175/WAF967.1

http://www.jondavies.net/tornado_fcsting/500mbcoldcorelow_tors.htm

 

[DNewman]

Thanks Dan.

 

[DNewman]

The only thing about those studies is that they do not specifically mention the study of "occluded" fronts, but rather the 500 mil cold core lows. Obviously there needs to be more research specifically geared towards severe weather/tornadic weather associated with "occluded fronts".

 

[Caleb Routt]

When it comes to boundaries, it honestly doesn't matter what "kind" of bondary there is. Warm fronts usually contain baroclinic generated vorticity that a supercell can draw in and stretch at low levels to produce a circulation. Cold fronts can at times take over for not being a warm front, but usually storm motions are paralelling the boundary and the storms would have a tendency to become linier because then the precip can interact with the storm's cold pool. Dry lines happen because dry air is advecting and coming into a moist environment and don't often have boundary paralell storm motions because in order to advect a that air mass the wind must be blowing across the boundary. (Hopefully the image below helps)

As for occluded fronts there have been tornadoes associated with them. But usually occluded fronts have relitivly low moisture out ahead of them so LCL heights are a bit higher so that does keep the tornado threat down. Unless you have some kind of dynamicly induced pressure falls within a circulation. The best example I could find was the tornado that happend in Huntsville Alabama back in 2010. (pic below) here is a link: http://www.srh.noaa.gov/hun/?n=january2010_severewx-wxsetup

There was a triple point and an occluded front can be seen. So it really dosnt matter what kind of front you have as long as it's not too sharp that it undercuts the updraft and the winds are largely paralell to it.

 

[DNewman]

Here's a great example I found after some research about a tornado outbreak in Texas on December, 29,2006. Which occurred with an occluded front! It was specifically pointed out information about this occluded front which was in part responsible for these tornadoes (in addition to extreme amounts of wind shear & moderate instability).
http://www.srh.noaa.gov/fwd/?n=toroutbreak2006retro