What happened? A brief explanation on the why's and how's of such a bad chase year for many are outlined below.
1). El Niño ... This is a warming of the eastern tropical Pacific off South America near the equator. It's a 2 to 5 year cycle (ENSO) and causes a "trough-east and ridge-west" pattern over North America with the "dreaded" Hudson-Bay Vortex pattern in the late Spring. The ridging over the western US is very BAD for storm chasing prospects there, especially during prime chase season, from Mid May to Mid June. The same pattern also caused most low pressure systems entering the central USA to be generally weaker than normal. Forecast models also performed very bad this year, making a planned chase trip very difficult. A three-week-long "death ridge" also plagued the central US in May 2009, forcing me to cancel my 10 day chase trip there.
2). Unusually inactive Atlantic Basin hurricane season. Also due to the effects of El Niño, which ruined chase prospects for severe weather in the central USA, also ruined any hurricane chasing opportunities. The El Niño causes strong winds aloft, not over the central US, but over the tropics, due to the "tough-east" pattern. The upper-level shearing associated with such a pattern supresses development of tropical cyclones, along with dry air in the mid levels. Any tropical cyclones that did develop were short-lived, generally weak, or over unusual areas of the Atlantic Basin. In response, the Pacific basin, especially the western Pacific, was ABOVE normal in 2009.
3). Bad timing - This was the most serious problem in 2009. Anyone may disagree with me, especially seeing other chasers success, especially in Mid-Late June of 2009 (if you see Reed Timmer on "Storm Chasers", you'll know what I mean). Not everyone had a bad year in 2009. Fellow chaser Jim Edds even went to Guam for a while to take advantage of the ABOVE normal Pacific typhoon season in 2009. My situation was very bad timing, and work conflicing with available chase time. For example, the ONLY good week in the central US in 2009 was around June 17 ... But that week, with my boss on a funeral and me filling in for another on a cruise, that was the ONLY week I could NOT take off and chase.
With planning for next year (2010), hopefully this El Niño pattern will fade to a neutral ENSO or even a mild La Niña (it's opposite). The La Niña pattern is much better for central USA chasing in the spring, and a better tropical season in the Atlantic basin to follow. Good chase years, such as 1995, 2004, 2005, and 2008 were all La Niña years, with a "tough-west and ridge-east" pattern lacking the Hudson-Bay Vortex. In spring and summer 2010, I will also have a lot more time to take off, given I am still working at the time.
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