Sunday, October 28, 2012

What comes after red?

We're all familiar with weather maps in which the colors represent different wind strengths. There is a progression from green to yellow to orange to red as the wind strength increases. Red is reserved for the highest wind speeds we get around here, 50 - 60 mph.

Today we learned the color that comes after red. It is brown. Brown is the color reserved for 75 mph. Here's the wind gust forecast for 2pm tomorrow (Monday).

I really don't want to know what comes after brown.



Anonymous said...

Is there lift in the eye of the storm?

Rick said...

Convection is unlikely. It is hard to imagine a parcel of air that has a lower density than low pressure air at the center.

There may be lift due to wind, however. Think of what what happened to Dorothy and Toto.

Anonymous said...

It's a low pressure center. I.e., air is moving into the center from the outside (although mostly just rotating around it). That ingoing air must go somewhere! Presumably it rises, if not in the eye then somewhere near it.

Anonymous said...

The incoming air never gets to the eye, it gets acellerated and spun counter clockwise around the eye. The high wind velocities produce the low pressure (remember Bernouli?) which draws air out of the eye, dropping its ambient pressure almost 100 millibars.

If you'd like to learn more about hurricanes, go down to Norfolk, VA and duct tape yourself to a tree (use the whole roll), today!