National Weather Service United States Department of Commerce
 
 
Regime 1 Regime 2 Regime 3
Regime 1 Mean Vector Flow Regime 2 Mean Vector Flow Regime 3 Mean Vector Flow
1000-700mb Mean Vector Flow:
Light/Variable <4 knots
70 Total Days in Climatology
1000-700mb Mean Vector Flow:
E/NE 4 knots ≤ Wind ≤ 10 knots
220 Total Days in Climatology
1000-700mb Mean Vector Flow:
E/NE >10 knots
112 Total Days in Climatology
 
 
Regime 4 Regime 5 Regime 6
Regime 4 Mean Vector Flow Regime 5 Mean Vector Flow Regime 6 Mean Vector Flow
1000-700mb Mean Vector Flow:
W/SW 4 knots ≤ Wind ≤ 10 knots
334 Total Days in Climatology
1000-700mb Mean Vector Flow:
W/SW >10 knots
217 Total Days in Climatology
1000-700mb Mean Vector Flow:
S/SE 4 knots ≤ Wind ≤ 10 knots
339 Total Days in Climatology
 
 
Regime 7 Regime 8  
Regime 7 Mean Vector Flow Regime 8 Mean Vector Flow  
1000-700mb Mean Vector Flow:
S/SE >10 knots
183 Total Days in Climatology
1000-700mb Mean Vector Flow:
N/NW 4 knots ≤ Wind ≤ 10 knots
84 Total Days in Climatology