Wednesday, March 6, 2013


We are a week into March. Woo Hoo chase season, Spring!!! But wait...something isn't right. Thats right, Chicago just received 9.5" of snow yesterday making it the largest snowstorm since the GHD blizzard back in February 2011 as well as a top 4 March snow event in all of Chicago's 128 year weather history.

The start of March is an exciting time for most people. Spring is just around the corner, warmer weather, better times, sunnier skies and stormier days. No group of weirdos on the planet await this time of year with more anticipation than storm chasers, which I consider myself to be (a subjective definition if ever there was one, but I believe I fit the bill in my own biased eyes.)

So...where the hell is spring?!?!?!? Lets turn the trustworthy forecast models. (click to enlarge image)


While fluctuations like this are normal, especially in the long range, these are pretty radical. Overall the trend has been colder than normal though, with only brief spells of mild weather. Every now and then we'll get teased by a few runs that look warmer and more spring-like, only to be followed up by more runs showing colder than normal temps.

So we can't look there. Where else can we look? While I don't consider myself an expert and noone should view me as such. Over the years I have become a huge fan of the teleconnections, especially one known as the NAO (North Atalintic Oscillation.) Basically it has to do with ocean currents and how they affect the jet stream. Like all weather patterns it fluctuates.

A positive pattern promotes west coast troughing, a pattern more favorable for severe weather while a negative pattern promotes east coast troughing and generally cooler weather across the US. Not good for large scale severe weather patterns. I have been observing this for a couple years now, and found it to be pretty accurate (but like anything with weather, it isn't 100% garauntee) Taking a look I am not seeing much love here either, but a low trend towards hopefully a positive phase is better than nothing. I have also marked 2 recent noteable tornado outbreaks and both correlate with a positive phase.

Notice in February we tanked into a negative phase, and suddenly winter arrives and take a stronghold for many in the heartland. The forecast seems to go along with the general cold trend seen on the models, another sign I am not a fan of.

All of this is hard to digest for a severe weather lover such as myself as I am not seeing many of the signs I normally would like to see come spring time. It is far too early to sound the panic alarm though. This type of pattern is not unheard of this time of year, and sometimes things get off to a slow start. 2008 was the only year in my chase career I didn't chase in March, and 2008 set a record number of tornadoes for the country. Anything can happen.

All it takes is a sudden pattern change and BAM, things light up. Unfortunately, such a pattern doesn't look to be in the cards just yet. There will be marginal setups along the way though, and even slow patterns have their fare share of severe weather producing setups, just not the kind to lure someone like me from Chicago to Kansas.

My advice to those eager to get out who can't sit still is to take advantage of what appears to be a slow start. Fine tune your projects, double check all that vehicle maintenance. Put in some overtime at work to stock up on time off for when things do decide to change. 

It will happen...

1 comment:

Anonymous said...

Actually, a positive PNA favors west coast riding and east coast troughing. The negative PNA favors a west coast trough and east coast ridge.