Saturday, April 9, 2011

Today: wow

Today is one of those days I wish I could be chasing. However, were I chasing today I would be facing a monumental decision. Let's take a look.

First off, there's good moisture return to the central plains, with dews in the mid to upper 60s.

Second off, there are crazy lapse rates out there.

Deep wind shear is not going to be a problem, as there is plenty of strong wind off to the west, with a deep trough in place.

Lift is the key here, and there are 2 places for it. This is what I really want to talk about.

Days like this really aggravate me. I am torn when two distinct locations for chasing are evident. What are you talking about, Dave?

Today is a classic plains cyclone setup. A low has formed in Colorado and will move eastward today and deepen, drawing moisture northward with it. To its east will be a fairly strong warm front, to its southwest a cold front, and to the south will sit a dryline. This is the concern.

See, the typical area to chase, the place where most chasers would aim for, is the triple point--the intersection of all three, which is likely to be somewhere northwest of Omaha, Nebraska. This is where you get the best juxtaposition of all the necessary ingredients. Let's have a look at all of these from the 12Z NAM, courtesy of Twister Data.

Surface map with temperatures, showing the warm front

500 mb winds and temperatures

Surface map with dewpoints, showing the dryline and warm front


As you can see, the SBCAPE is progged to be rather big today, over 2000 J/kg over a huge area, the cap is forecast to be minimal or break completely over the whole area, and EHI values show good potential for storm rotation.

But where to go, where to go?

Conventional wisdom, like I mentioned before, would favour the triple point. It has a few things going for it:
  1. High likelihood of storms
  2. High likelihood of tornadoes, including maybe some strong ones
  3. Good chase country

It also has a few things against it:
  1. Possibility of storms being on the warm front, close to being mired in low cloud and fog
  2. Too many chasers going to be there
  3. There could be a lot of storms

All that being said, here are forecast soundings for the triple point and the dryline, respectively.

I would say wow for either of these, but the triple point one has my jaw on the floor with a YOWZA.

So I think that today, despite the potential negatives, and despite my nickname, I couldn't pass up the golden opportunity to chase a classic plains cyclone setup. This looks too juicy a setup not to chase. If, though, I got some information saying that this area would be less perfect, I would book it to north-central Kansas and chase the dryline. The storms there will be more isolated and likely more photogenic. That being said, water vapour imagery shows a good wave heading toward the Nebraska target area, making storms there much more likely.

Happy and safe chasing to everyone out there!

Wednesday, April 6, 2011

Getting antsy

So there have been a few good outbreaks in the south, including this incredible day of over 1000 severe reports.

I have the new laptop and I have loaded all the software onto it. I have been practicing my forecasting and soon I'll be in top shape. Now all we need is chase-able storms.

This weekend looks like a good few-day setup. The moisture is just beginning to creep northward, so it looks like the threat will be in the southern plains. until our chasecation I don't think I'll have enough time to go chasing, although there's a short time period that would work if things come out just right.

Bring on May!!!