Tides and currents trainer
ASA 101 is a protected-water, beginner keelboat course, but tide and current judgment decides whether a simple day sail stays simple. Practice the habits: check a local source, protect depth under the keel, time current gates, and keep margin when wind opposes current.
Saved tide-window planner
Saved locally in asa101.tidesCurrents.v1. It feeds Progress backup, Readiness, and Exam cram.
1. Tide depth window
2. Current set and drift
Tide/current picture
Skipper brief
Run both calculators, then save the worksheet.
Visual tide/current window simulator
Pick the safest beginner skipper window from a simple tide/current picture. Each run saves under windowRuns; missed calls become weak-review topics.
Saved tide and current drill
Practice flood, ebb, slack, depth, current gates, anchoring, and wind-against-current calls. Misses become a weak-review deck.
Beginner tide-current checklist
| Check | Beginner habit | Why it matters |
|---|---|---|
| Station/source | Use the nearest NOAA tide/current station, then apply local knowledge. | A station across a bay may not match a creek, marina entrance, or inlet. |
| Depth | Charted depth + predicted tide - expected fall - draft - margin. | Groundings happen when the return path gets shallower than the departure path. |
| Current | Know set, speed, flood/ebb direction, and slack timing. | Current changes course over ground, dock approaches, and stop distance. |
| Wind against current | Expect steeper, rougher chop and choose a conservative route. | A light-air beginner sail can become uncomfortable when wind opposes water flow. |
| Anchoring | Add tide rise to scope and allow swing room for wind/current shifts. | Too little rode or changing current can drag or swing the boat into trouble. |
Key terms
Flood
Current associated with rising water, often moving into a bay, harbor, or river system. Local geography decides the exact direction.
Ebb
Current associated with falling water, often moving out toward sea. It can be strong in narrow entrances.
Slack
The short period around current reversal when current speed is minimal. Slack is often the easiest time for a beginner current gate.
Set and drift
Set is the direction the current moves. Drift is how far it carries you over time.
Sources
- NOAA Tides and Currents - local water levels, tide predictions, current predictions, and oceanographic conditions.
- NOAA Tide Predictions - station-based tide prediction lookup.
- NOAA Current Predictions - station-based current prediction lookup.
- NOAA Tides and Currents Education - tide and current education, lesson resources, and definitions.
- NOAA Tides and Currents Glossary - official definitions for tide and current terms.
- America's Boating Club - Tides and Currents - boater-focused seminar topics for tide height, current flow, tables, low-tide navigation, NOAA charts, and anchoring.
- American Sailing - Tips From Tides and Currents - sailor-focused notes on tide range, planning, wind against tide, and NOAA tide tools.
Plan a tide windowPractice chartworkBuild weather briefBuild float plan