Station Windrose Product Summary Documentation


Pasquill-Gifford Stability Class (Std. Dev. Dir. - sigma A)

Pasquill-Gifford stability classification by Wind Direction Std. Deviation

Initial Classification.

Class A : Std Dev < 3.8 deg.
Class B : Std Dev 3.8 to 7.5 deg.
Class C : Std Dev 7.5 to 12.5 deg.
Class D : Std Dev 12.5 to 17.5 deg.
Class E : Std Dev 17.5 to 22.5 deg.
Class F : Std Dev > 22.5 deg.

Final Classification.

Initial Classification 10-meter wind speed (m/s) Final Classification
Daytime
A u < 3 A
A 3 <= u < 4 B
A 4 <= u < 6 C
A 6 <= u D
B u < 4 B
B 4 <= u < 6 C
B 6 <= u D
C u < 6 C
C 6 <= u D
D,E,F Any u D
Nighttime
A u < 2.9 F
A 2.9 <= u < 3.6 E
A 3.6 <= u D
B u < 2.4 F
B 2.4 <= u < 3.0 E
B 3.0 <= u D
C u < 2.4 E
C 2.4 <= u D
D Any u D
E u < 5.0 E
E 5.0 <= u D
F u < 3.0 F
F 3.0 <= u < 5.0 E
F 5.0 <= u D

Questions about output or comments can be directed to
Western Regional Climate Center,
wrcc@dri.edu


Return to previous page