Spring Has Sprung?

[WxFish]

I'm a meteorlogist that has been practicing air pollution stuff for about 30 years and am just now getting back into forecasting. I have forgotten most of what I learned back in the 70's. So I am looking for wisdom from you guys whose skills are well honned. I have been really spending some time on forecasting since last summer, and it looks to me like we have had a real quick transition in the upper air pattern away from the winter time pattern. The specific things that I have observed are; the 500mb long wave pattern switched (the long wave trough that has been hagning around 180W all winter shifted to about 140W) and the 300mb jet transitioned from the north-south pattern into a zonal flow. Both of these patterns switched in about a week. First question, am I reasing the signs of transition from winter to spring correctly? Secondly, is this the normal time frame for the transition?

[wxforecaster]

I guess the First Dryline setup could mean Spring as started! It was a COLD winter though. Burrrr. This should be fun. We are Dryslotting here on the cap but off the cap.. if you get enough heat.. you will be good to go!