This storm system and stationary front is also blamed for the flooding in the Ohio area.
The derechos developed along the northern rim of the air mass on a stationary front.
An area of low pressure formed along a stationary front draped over central Minnesota and moved slowly northeast.
The depression later moved to the northeast before it was absorbed by a stationary front on September 7.
A stationary front is a boundary between two different air masses, neither of which is strong enough to replace the other.
It is a stationary front as the air masses are not moving against each other.
Historical weather maps indicate that a low pressure area was embedded within a west to east oriented stationary front on September 24.
To the east of the stationary front, temperatures and dew points were unseasonably high.
A deepening area of low pressure over Kansas ejected to the north, moving along the stationary front.
The carrier group evidently expected him to head east and duck under this stationary front.