Triple Point

[shane turner]

First off is the triple point where the dryline is seperated by warm moist air at the surface and cold air aloft. Is this a pretty good area to target when chasing tornadoes? Is finding a triple point pretty difficult or is it usually pretty obvious? Are there any advantages or disadvantages regarding the triple point? Just hear it discussed quite a bit when chasing and wondering if its a very important area when chasing tornadoes. Also chasers have fun the next few weeks to a month and be careful. I wish I could be there with you but I dont have any money to chase.

[Paul Knightley]

A triple point is defined as the meeting point of 2 other boundaries, such as a cold front and dry-line; a warm front and cold front; a warm front and dryline, etc etc.

They are favourable for thunderstorm development due to the enhanced lift given to air parcels in the area. In addition, surface winds can be backed near it, enhancing low-level shear.

[Darren Addy]

An example: (It is a surface feature)

http://members.cox.net/jdavies1/041803cne/minisprcltor_composite.gif

[dentonsachs]

I chased a supercell that was very foreign to me the other day. A Low topped supercell, associated with a upper-level low, this cell produced a fairly high base, slight rotation, and even a small funnel at one point. This was extremely perplexing to me, and wondered about the frequency of these, and exactly how they form, are they always associated close to a low pressure area?

[Connor McCrorey]

My first tornado was on 3/26 this year, a day that was very much a triple point chase. A warm front set up along the Red River, while a dryline formed a few counties west of I-35. The cap was very strong that day, but extra lift near the triple point got two lone supercells going a couple of hours before dark. They then rode just south of the warm front, producing tornadoes and hail to the size of baseballs.

[Rich Thompson]

Shane,

In case you're wondering, the "triple" point refers to the intersection point of 3 different air masses. In most chase situations, the triple point refers to the warm front-dryline intersection (usually cool north, warm south, dry west), or the dryline-cold front intersection (warm east, dry southwest, cool northwest).

The intersection of boundaries can be a favored area for thunderstorm formation because focused low-level lift erodes the cap from below.

Rich T.