"Ask Steve" Lots of Local Weather Trivia

[Skytripper]

As a meteorology major years ago, I can also add to this......

Tornadoes NEED lots of warm (hot) air to form from thunderstorms that can grow high into the atmosphere......they NEED lift, which is usually provided by an approaching cold front, and spin, which is provided by a strong jet stream and windflow which tends to support this spin at other levels of the atmosphere. Couple these with the fact that tornadoes also have a very hard time forming in areas with mountains around and you can see why Washington....and MANY other locations just do not support the development of tornado-producing thunderstorms.
The climate out here on the West Coast does not favor it, nor the topographic features.
Occasionally, a WEAK tornado CAN form here and does so.....usually with the help of an approaching LOW pressure system that has a LOT of energy associated with....one that is providing a lot of LIFT/Convection. Very rare just to get thunderstorms here in the NW....but most likely....they happen in the Fall-Spring months...(Summer too....but more likely....EAST of the Cascades)... and just bring a good downpour, a few flashes of lightning and possibly some small hail.
In the Central US......EVERYTHING is PERFECT for tornado development....geographically-speaking....especially when the "right" conditions come together and that tends to be most likely....the Spring and again, a second time of year....the Fall....as more potent cold fronts start sweeping down from Canada or across the Rockies.....and clash with super warm and humid air from the Gulf of Mexico, hot, DRY SW airflow in the mid-levels, cold air behind a front providing plenty of lift.....along with a strong SW-NE jet stream/approaching Upper-level LOW....providing lift and spin at different levels of the atmosphere......all coming together. Further South.....tornadoes can occur at ANY time of year, whereas further north.....tends to shift the liklihood more into the Summer months as the jet stream "retreats" to the north.
Hope this also helps and makes sense.

[brightcopperkettles]

It does; thank you!

[scirocco22]

Thanks for reporting back, bck!

[brightcopperkettles]

My pleasure, as always, 'rocco!!