Let me first explain what made last year the storm chasing super turkey it was, and then explain what makes me so optimistic about the chase potential this year.
Like Stan mentioned, last year moisture (or the lack thereof) was a serious issue. But what was an even bigger issue, especially in the western Great Plains, was the
constant wind. It was the windiest and warmest winter and early spring anyone around here remembers, I think we only had maybe two dozen days at most between November and May where the wind wasn't blowing and we had only
22 inches of snow between October and April at our farm; our 'normal' snow total is around
55 inches.
What the wind did was completely dessicate the soil profile, and since there was no moisture to replace it, every time the wind blew it kept sucking more moisture out of the soil. We had to dig out a hydrant in late April, and we discoverd that the soil profile was bone dry until you got
5 1/2 FEET DOWN! This lack of moisture kept the grass from greening up in the western High Plains until almost June and prevented farmers from planting many of their crops because there was no moisture to sustain them. You ask, what does this have to do with the abysmal chase season last spring/summer?
Everything.
Most everyone here is familiar with transoevaporation. In a normal year, the peak heating evapo-transpiration from the grass, crops etc. and from the soil itself help increase the dewpoint values by 5-10 degrees during the mid to late afternoon hours. The problem is that because of the combination of the constant wind and the lack of moisture, the entire Great Plains soil profile was Atacama desert dry, the grass greened up two months late, and a lot of the crops (wheat, triticale, grain sorghum, etc.) which normally would have been providing daytime evapo-transpiration hadn't been planted. This in turn resulted in lower dewpoints/higher LCL's all season long, which made it next to impossible for tornadogenesis to occur even in the most fantastic shear and forcing setups. Also the soil temperature was far warmer than it normally would have been, which helped create the 'unbreakable' caps which resulted in the many bust situations we endured last year.
The wind, warmth and abnormal dryness of last winter was directly responsible for making 2006 the terrible chase year that it was.
This winter, at least thus far, is a completely different animal from last year. At our farm, I've recorded 34.5 inches of snow since October, which is already one and a half times as much snow in four months as we accumulated in seven months last year. At this point it appears the storm/jet stream track we've been seeing since the middle of December is going to continue to persist across the Southwest/southern Plains through at least March, if not longer. I totally agree with Jason; If this pattern does persist, I can say with a fair amount of confidence that the Southern and Central Plains will likely see some awesome outbreaks at least through late spring. It's a little too far out to speculate reasonably about the summer months, but I can say this: if we continue getting good moisture the rest of the winter and into this spring, and the farmers are able to plant the crops they couldn't plant last year, and the grass greens up when it's supposed to, the evapo-transpiration from those crops and that grass is going to play a significant role in raising dewpoints/lowering LCL's during the late spring/early summer, and at the very least increase the chances of tornadogenesis occurence.
![Big Grin :D :D](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I, as much as the rest of the ST community, am painfully aware that a lot of things could change between now and spring; in recent years there has been so much variability from season to season. There is no single, established long term weather pattern which we can use for reference and guidance, but rather a plethora of smaller patterns with one or two distinguishing features and a host of variables which can be present in several different patterns, which can fool us into believing we're in one weather pattern when we're really in another.
About all that we can do is attempt to identify the primary pattern indicators, using prior experience and knowledge from which we can put forth our best guess as to what variables will occur within the main pattern. When the variables manifest themselves, then, and only then, can we can make a truly informed forecast. That's meteorology for you.
![Wink ;) ;)](data:image/gif;base64,R0lGODlhAQABAIAAAAAAAP///yH5BAEAAAAALAAAAAABAAEAAAIBRAA7)
I have a gut feeling that 2007, if anything, will
overcompensate for 2006. It seems that in meteorology, as in life, things tend to swing from one extreme to another, and amidst the chaos caused by the respective extremes, perfect balance is achieved.