Warm Fronts

[uwochris]

Hey guys,

If a warm front is the leading edge of a warmer air mass advancing towards a cooler one (I know some books define it differently... as the retreating edge of a cold air mass) and overuns along the cooler, denser air, how can the surface temps be affected by 5-10 degrees Celcius?

It seems like a paradox to me... if the warm air is overrunning the colder air ahead, shouldn't only the upper air temps be affected? It's not like cold front, which "hugs" the ground.

Thanks in advance!

 

[avbug]

Chris,

The slope at the boundary between the two airmasses may be steep or shallow, and it's seldom a hard line. You may see a rapid temperature change with a fast moving front, or a slow, gradual one. Sometimes a slight temperature change and a wind shift, and that's it.

The pressure differential of the two masses will also make a difference. While temperature determines the slope to some degree so does the pressure gradient, as well as winds aloft.

You may also see variations due to an occluded, or stationary front.

It's not unusual at all to see a warming trend prior to frontal passage.