WFO Baltimore-Washington forecasts significant wave heights in the local Coastal Waters Forecast (CWF) product. Significant wave heights are the average heights (trough to crest) of the one-third highest waves. For simplicity, significant wave heights are termed waves in the WFO Baltimore-Washington CWF.
For wave forecast guidance over the Maryland portion of the Chesapeake Bay and Tidal Potomac River, WFO Baltimore-Washington uses the NWPS model. Where the NWPS domain is incomplete and beyond the NWPS time period (102 hours), wind-wave correlations are used for wave forecasts. Those correlations are outlined below.
Generally, for wind speeds of 5 kt, waves will read "less than 1 ft." For other wind speeds, the correlations below are utilized for each marine zone. Remember that forecasts of wave heights do not include effects of wind direction relative to tidal currents. Expect higher waves when winds are blowing against tidal flow.
W | NW | N | NE | E | SE | S | SW | |
10 KT | <1 | <1 | <1 | <1 | <1 | <1 | <1 | <1 |
15 KT | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
20 KT | 1 | 1 | 2 | 1 | 1 | 1 | 2 | 1 |
25 KT | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
30 KT | 2 | 2 | 3 | 2 | 2 | 2 | 3 | 2 |
35 KT | 2 | 3 | 3 | 3 | 2 | 3 | 3 | 3 |
40 KT | 3 | 3 | 4 | 3 | 3 | 3 | 4 | 3 |
45 KT | 3 | 4 | 4 | 4 | 3 | 4 | 4 | 4 |
50 KT | 3 | 4 | 4 | 4 | 3 | 4 | 4 | 4 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | <1 | 1 | <1 | <1 | <1 | 1 | <1 | <1 |
15 KT | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
20 KT | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
25 KT | 2 | 3 | 2 | 2 | 2 | 3 | 2 | 2 |
30 KT | 2 | 3 | 2 | 2 | 2 | 3 | 2 | 2 |
35 KT | 3 | 3 | 3 | 3 | 3 | 3 | 3 | 3 |
40 KT | 3 | 4 | 3 | 3 | 3 | 4 | 3 | 3 |
45 KT | 3 | 4 | 4 | 4 | 3 | 4 | 4 | 4 |
50 KT | 4 | 5 | 4 | 4 | 4 | 5 | 4 | 4 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1 | < 1 | < 1 | 1 | 1 | < 1 | < 1 |
15 KT | 2 | 2 | 1 | 1 | 2 | 2 | 1 | 1 |
20 KT | 2 | 3 | 2 | 1 | 2 | 3 | 2 | 1 |
25 KT | 3 | 4 | 2 | 2 | 3 | 4 | 2 | 3 |
30 KT | 3 | 5 | 3 | 2 | 3 | 5 | 3 | 2 |
35 KT | 4 | 5 | 3 | 3 | 4 | 5 | 3 | 3 |
40 KT | 4 | 6 | 4 | 3 | 4 | 6 | 4 | 3 |
45 KT | 5 | 6 | 4 | 4 | 5 | 6 | 4 | 4 |
50 KT | 5 | 6 | 4 | 4 | 5 | 6 | 4 | 4 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
15 KT | 1 | 1 | 1 | 2 | 1 | 1 | 1 | 2 |
20 KT | 2 | 2 | 2 | 2 | 2 | 2 | 2 | 2 |
25 KT | 2 | 2 | 2 | 3 | 2 | 2 | 2 | 3 |
30 KT | 3 | 3 | 3 | 4 | 3 | 3 | 3 | 4 |
35 KT | 3 | 3 | 3 | 4 | 3 | 3 | 3 | 4 |
40 KT | 4 | 4 | 4 | 5 | 4 | 4 | 4 | 5 |
45 KT | 4 | 4 | 4 | 5 | 4 | 4 | 4 | 5 |
50 KT | 5 | 5 | 5 | 6 | 5 | 5 | 5 | 6 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
15 KT | 1 | 2 | 2 | 2 | 1 | 2 | 2 | 2 |
20 KT | 2 | 3 | 3 | 3 | 2 | 3 | 3 | 3 |
25 KT | 2 | 3 | 4 | 3 | 2 | 3 | 4 | 3 |
30 KT | 3 | 4 | 5 | 4 | 3 | 4 | 5 | 4 |
35 KT | 3 | 4 | 5 | 4 | 3 | 4 | 5 | 4 |
40 KT | 4 | 5 | 6 | 5 | 4 | 5 | 6 | 5 |
45 KT | 4 | 5 | 6 | 5 | 4 | 5 | 6 | 5 |
50 KT | 5 | 6 | 7 | 6 | 5 | 6 | 7 | 8 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
15 KT | 1 | 1 | 2 | 1 | 1 | 1 | 2 | 1 |
20 KT | 2 | 2 | 3 | 2 | 2 | 2 | 3 | 2 |
25 KT | 2 | 3 | 4 | 3 | 2 | 3 | 4 | 3 |
30 KT | 3 | 4 | 5 | 4 | 3 | 4 | 5 | 4 |
35 KT | 3 | 4 | 5 | 4 | 3 | 4 | 5 | 4 |
40 KT | 4 | 5 | 6 | 5 | 4 | 5 | 6 | 5 |
45 KT | 4 | 5 | 6 | 5 | 4 | 5 | 6 | 5 |
50 KT | 5 | 6 | 7 | 6 | 5 | 6 | 7 | 6 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1 | 1-2 | 1-2 | 1 | 1 | 1-2 | 1-2 |
15 KT | 2 | 2 | 3 | 3 | 2 | 2 | 3 | 3 |
20 KT | 2 | 2 | 4 | 3 | 2 | 2 | 4 | 3 |
25 KT | 2 | 3 | 5 | 4 | 2 | 3 | 5 | 4 |
30 KT | 3 | 4 | 6 | 5 | 3 | 4 | 6 | 5 |
35 KT | 3 | 4 | 6 | 5 | 3 | 4 | 6 | 5 |
40 KT | 4 | 5 | 7 | 6 | 4 | 5 | 7 | 6 |
45 KT | 4 | 5 | 7 | 6 | 4 | 5 | 7 | 6 |
50 KT | 5 | 6 | 7 | 6 | 5 | 6 | 7 | 6 |
W | NW | N | NE | E | SE | S | SW | |
10 KT | 1 | 1-2 | 2 | 1-2 | 1 | 1-2 | 2 | 1-2 |
15 KT | 2 | 2 | 3 | 2 | 2 | 2 | 3 | 2 |
20 KT | 3 | 3 | 4 | 3 | 3 | 3 | 4 | 3 |
25 KT | 4 | 4 | 5 | 4 | 4 | 4 | 5 | 4 |
30 KT | 4 | 4 | 6 | 5 | 4 | 5 | 6 | 5 |
35 KT | 5 | 5 | 7 | 6 | 5 | 6 | 7 | 6 |
40 KT | 5 | 5 | 7 | 6 | 5 | 6 | 7 | 6 |
45 KT | 6 | 6 | 8 | 7 | 6 | 7 | 8 | 7 |
50 KT | 6 | 6 | 8 | 7 | 6 | 7 | 8 | 7 |