Airflow, from High to Low

by

Shannon O'Donnell“No more wind for me, ever! No more wind for me, ever, EVER!”

Such were the words of my 2-year-old nephew upon visiting San Francisco during the windy spell that kicked off our Memorial Day Weekend. We were walking the boys in their strollers over a very gusty hillside in San Francisco, and the wind was absolutely howling in from over the ocean.

So where does wind come from–what causes the air to ‘move’ so much during a wind storm? It all has to do with how ‘deep’ the area of low pressure (fancy-meteorologist-speak for ‘storm’) is that is coming in, and how much it contrasts with any nearby areas of higher pressure.. If the low, or storm center, is very strong and it’s central pressure is very low, a strong pressure gradient, or difference in pressure, develops. The atmosphere tries to ‘balance out’ this difference in pressure by throwing a lot of air from the high toward the low to ‘fill it in’. Thus, the low acts like a giant vacuum, sucking and whooshing air into itself. As the low center ‘fills up’, the winds die down.

We’ve had some pretty significant wind storms on the west coast, but the gusty low pressure centers that more often make headlines tend to hit the OTHER side of the country…they’re otherwise known as HURRICANES.

With hurricane season beginning soon, we’ll talk about how hurricanes get their names next time.

Ciao and have a happy and safe Memorial Day Weekend!

Shannon O’Donnell
NBC11 WeatherPlus Meteorologist

Advertisements

Leave a Reply

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: