Posted by NBC12 Meteorologist Jim Duncan
The way our world seems to work these days is that whenever anything seems out of the ordinary, we must seek out the reason why. The weather is a frequent target for such inquiries, chiefly because it’s rarely normal and thus the subject of special intrigue. This year’s tornado season has been one of the busiest in years, making news headlines seemingly every couple of days. The reason it’s been so active is simple. The strong “la nina” driven wind patterns aloft from this past winter have trickled forward into spring. The result has been an unusually strong northern jet stream that’s kept very cool air spilling southward, which then meets up with warmer southern air, ultimately leading to frequent atmospheric “collision-zones”. We’ve seen this happen a lot this year, but it’s no mystery, just a consequence of naturally occurring weather cycles.