What produces more severe storms? dry lines or cold fronts?

[Mike Johnston]

Yeah, but it was Miller's pioneering use of oceanographic techniques that really analyzed the atmosphere in layers and was the breakthrough in their tornado forecast method.

 

[Paul Knightley]

But of course it was more down to the pioneering work in the 60s and 70s that we discovered the deeper relationship between vertical wind shear and storm-scale rotation, e.g. by Browning. And empirical techniques have largely fallen out of favour with the ingredients methodology being the current preferred workflow.

 

[Lanny Dean]

@Jeff Duda What I actually meant Jeff, was that Miller wasn't alone, Fawbush played a vital role. You had mentioned just Miller, hence my reply. I am more than familiar with John Finley's role and couldn't agree more.

 

[James Gustina]

I invite you to read this BAMS article (http://journals.ametsoc.org/doi/pdf/10.1175/2010BAMS3062.1). While John Finley's forecasts weren't exactly the modern type that Fawbush and Miller pioneered, he indeed was the first to document any sort of prediction of tornadoes on short time scales.

He was quite the interesting character. I've read that he liked to fudge verification numbers on his forecast (e.g. counting it a success when he forecasted no tornadoes and none happened that he knew of) but the man was a solid 60 years ahead of his time. He got the general synoptic pattern down before anyone else did.

 

[Marshall Stoner]

East of the plains, major tornado outbreaks usually occur with a strong low pressure system that has both a warm front and a cold front. In most cases supercells don't form directly on the cold front though. They usually form on a pre-frontal trough that's ahead of the cold front but south of the warm front. They can also form near the warm front, or where the warm front and cold front intersect. The cold front itself usually isn't the best place to look for storm initiation. Storms that line up directly over a cold front happen more often in the winter or early spring when cold fronts are sharper but instability is less. In these cases the storms tend to organize into long squall lines rather than discrete supercells.

Of course there are exceptions. There's always exceptions. Mother nature can create a variety of severe weather setups. As a general rule though, it's better to look somewhere 100 miles or more ahead of the cold front. If you're located right on the cold front, you'll have an incredibly hard time catching up to any storms that form to the east. If you're east of the cold front and storms form to your west you can always wait for them to approach. This is especially true for non-plains outbreaks where cells tend to move much faster. Dryline storms are much easier to chase because they're typically slow moving and easy to spot visually. The warm sector of a tornado-producing low pressure system east of the Mississippi is often filled with broken low clouds. You just can't see the storms the way you can in the plains.

 

[Jeff Duda]

He was quite the interesting character. I've read that he liked to fudge verification numbers on his forecast (e.g. counting it a success when he forecasted no tornadoes and none happened that he knew of) but the man was a solid 60 years ahead of his time. He got the general synoptic pattern down before anyone else did.

It was called the "Finley affair" and may have been the beginning of verification of dichotomous forecasts in the field of meteorology. What you mentioned is that Finley reported his accuracy as around 96-97%, which is true, but is rather meaningless given the number of correct null forecasts and the lack of skill required to get so many "no" forecasts right. That's probably one of the reasons no one uses "accuracy" (hits + correct nulls / total forecasts) and instead prefer methods such as POD, FAR, CSI, and ETS (since they don't depend directly on the number of correct non-forecasts).

 

[Travis Davis]

I've had better luck with dryline storms. Probably a 2-1 ratio vs warm fronts.