National Weather Service United States Department of Commerce

Active Weather for the West, Warming in the East

The potential for heavy snow at higher elevations in the western U.S. will continue for many spots through the weekend. In the meantime, the eastern half of the continental U.S. will transition to above normal temperatures ahead of a pair of cold fronts next week that will bring readings back to closer to normal as we approach Thanksgiving Day. Read More >

 
 
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