Baltimore to Portland — sea route & marine weather
The sea route from Baltimore (USBAL) to Portland (USPWM) is about 796 nm — about 3 days at 10 kn. Along the route today (Aug 3): SSW wind 5–26 kn, waves 0.3–2.4 m. The baseline track is drawn on the chart; Calculate replans it for your vessel and live weather.
Passage facts| Sea-route distance | 796 nm |
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| Passage time at 10 kn | about 3 days |
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| Great-circle distance | 389 nm |
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| Baltimore | 39°17.0′N 76°37.0′W |
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| Portland | 43°40.0′N 70°15.0′W |
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| Reference vessel | 4.5 m draft, 10 kn cruise |
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10-day marine forecast — along the route
| Date | Wind | Gusts | Waves |
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| SSW 5–26 kn | 34 kn | 0.3–2.4 m |
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| NE 0–24 kn | 31 kn | 0.1–2.5 m |
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| SE 3–14 kn | 18 kn | 0.1–1.1 m |
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| S 4–15 kn | 19 kn | 0.2–1.1 m |
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| SSW 5–16 kn | 20 kn | 0.1–1.0 m |
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| WSW 4–17 kn | 22 kn | 0.1–1.1 m |
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| WSW 4–19 kn | 24 kn | 0.1–1.3 m |
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| W 3–11 kn | 16 kn | 0.1–0.8 m |
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| W 5–15 kn | 26 kn | 0.1–1.3 m |
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| NW 4–12 kn | 16 kn | 0.2–0.9 m |
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Forecast from the ECMWF IFS model run , waves from ECMWF WAM. Updated with each model cycle; the live chart below recalculates for your departure time and vessel.
Frequently asked
How far is it from Baltimore to Portland by sea?
The water route is 796 nm (1,473 km), computed on WXMarine's maritime routing network. The same distance applies on the return passage from Portland to Baltimore.
How long does the passage from Baltimore to Portland take?
about 3 days at a 10 kn cruise. Scale by your own speed: at half the speed it takes about twice as long. The planner on this page recalculates for your vessel and live weather.
What is the weather between Baltimore and Portland today?
Along the route today, per the ECMWF IFS run 2026-08-03 12z: SSW wind 5–26 kn, waves 0.3–2.4 m. The day-by-day table on this page covers the next 10 days.