air mass that is not moving is what?

Question

AIR MASS THAT ISNT MOVING IS _________>?????

Answer 1

Stationary or stagnant would be the "terms" most meteorologists like me would use. In some cases in the U.S. mainly in summertime an "Omega Block" occurs. The end result is several days even weeks of mostly clear skies across the eastern 2/3 of the states. Case on point would be the severe drought of 1988. On the flip side, there are cut-off lows. Those occur mainly when the low pressure loses its jet stream support and it sits and spins until another frontal boundary pushes it out or it literally precipitates itself out.
There's more possible answers, that relate a little bit more to an air mass, just like you're asking for. Have you ever heard of the Bermuda High or the Azores High? These two high pressure regimes are almost a yearlong weather phenomena. They may be weak at times, but they are still there. Ever wonder why few frontal boundaries make there way through the extreme deep south (south of I-10)? With the Bermuda High in place (though not right on the island, that's just it's name), return flow around the high produces southerly and southeasterly winds the majority of the time from the surface to several thousand feet above the ground, resulting in frontal boundaries to either decay where they are, or be forced to move in a more northerly component. In the summer, with the jet stream well into Canada it's not an issue, but with those winds I mentioned earlier, wind moves across the ocean and Gulf of Mexico (sea-level), rises as the air travels inland (orographic lift is a trigger for instability) and thunderstorms occur. Coincidence? Not really. Travel to the southeast in the summertime, chances are in the late afternoon, if it's not raining where you are, it is nearby.
And how about the heat low in the desert southwest. Wanna know why that's there? Hot air is less dense than cold air, so low pressure forms. This low pressure area usually forms in the northern Mexican desert/southern Arizona desert. Eventually with this low in place, the "monsoon season" begins. It usually lasts for two months or so. Thunderstorms are frequent mainly in the afternoon hours and can persist into early morning hours. I hope this helps you.

Answer 2

Quasi-stationary.

Answer 3

Its stationary!! it stays in one place. Doesnt move!!