Annapolis: a departure-source desk, not a generic city forecast.
Forecast sectors and coverage
Use the NWS upper/middle Chesapeake and tidal-Potomac zone map, then locate the specific Severn/Bay leg. Lower-Bay continuation needs its applicable issuing products, not the same start-point forecast.
Weather-sensitive legs
Separate the Severn River exit and open-Bay crossing. Annapolis station 8575512 is a local water-level/tide reference, not a stream measurement for the entire Bay; inspect timestamps, observed versus predicted levels and datum.
Observations, sea state and reassessment
Confirm the exact berth/entrance and an observation representative of the exposed leg, if available. Inspect timestamp, sensor status and forecast issue separately. Missing observations or local approach/current information remain explicit gaps; this page does not certify depth, navigability or port permission.
Worked planning scenario — not a live forecast
Compare two departure times at the harbour exit, first exposed leg and arrival ETA. Record the next official check and a verified alternative before the point of commitment. If the later option is better only at the berth, it has not yet improved the passage as a whole.
Official products by task
- NWS Baltimore/Washington marine — Upper/middle Chesapeake and tidal Potomac products, observations and links to lower-Bay forecasts.
- NOAA Annapolis station 8575512 — Water-level/tide station; a tide prediction is not a Severn River current measurement.
- NOAA NDBC observations — Station map and timestamped buoy/coastal records; inspect sensor availability and exposure.
- NOAA Tides & Currents — Predictions and observations are separate products; choose station, timezone and datum.
Sector names help you locate the issuing product; they are not an automatic route-coverage match. Open the current issue and check boundaries, issue time and validity. This page does not display current warnings; an unavailable product does not mean no hazard.
Waters and sailing options
- Chesapeake Bay
Assess the tributary, open Bay and destination separately; one town’s calm weather is not the Bay forecast.
- US East Coast
Select coastal, offshore and high-seas products for the waters actually crossed.
Countries & territories
- United States
Choose a bay, coastal, offshore, Great Lakes or ocean product for the actual track.
Map orientation
The approximate map centre is not an approach waypoint, track, depth survey or forecast-zone boundary. The third-party map loads only on request.
Build your passage brief
Bring your route, leg timings, vessel and crew profile, checked sources and reassessment triggers into the brief. Personal AI analysis and expert review are available to invited closed-test participants; a port page does not extend the calculation service’s coverage.
A Sailing Weather editorial guide to local conditions, practical passage preparation and marine-weather sources. Source and structure review: 27 September 2026. For a specific passage, check current issues, validity and forecast coverage. The skipper retains the final decision and responsibility.
Read the Annapolis gauge as a gauge, not a Bay-wide clearance
NOAA's Annapolis station 8575512 is the local reference linked here. Open the observation and prediction as distinct series, checking units, time and datum. A difference can be important to the departure berth or a shallow approach, but the level alone does not establish wind waves on the Bay or the flow at another channel. Any depth decision still requires the actual charted approach and vessel draught.
- NOAA Annapolis station 8575512 — Station-specific water-level and tide reference, not a Bay-wide current measurement.
- NOAA CO-OPS Tides and Currents — Separate measured water levels, tide predictions, current predictions and model forecasts.
Give the return from the Bay its own review time
For a Severn-to-Bay day, include an update before the return, not only the morning departure check. Review the warning and the Bay forecast for the return ETA, then compare a relevant exposed observation if available. If a delay or changed warning makes the planned crossing materially different, reassess while an already checked shorter route remains available. Do not treat the marina's comfortable conditions as confirmation of the open Bay.
- NWS Chesapeake marine desk — Upper/middle Bay products and links to the lower-Bay issuer, observations and wave guidance.
Editorial review of this material: 27 September 2026. This date concerns the page content; check current forecast issue times and validity at the original sources.