Marine Weather for Boaters: A Practical Guide to Forecasts, Pressure Systems, Fronts, Storms, Sea State, Weather Routing, and Onboard Instruments

Weather decides more of a passage than any other single factor. It decides whether you go, which route you take, how long it takes, how comfortable it is, and sometimes whether the trip is safe at all. The forecast tells you what is expected; understanding the weather tells you what that forecast means for your boat, in your waters, at the time you will be out there.

This book works from the forecast outward. It starts with where forecasts come from and how to read one line by line, explains the systems behind them so a forecast becomes a picture rather than a list of numbers, works through what those systems do to the sea, and finishes with planning a passage around a weather window and using the instruments on board to see what is really happening.

WHAT IS INSIDE

Weather at sea: why marine weather is its own subject, the atmosphere in outline, where forecasts come from, units and conversions, and why the issue time matters as much as the content.

Reading a forecast: the structure of a marine bulletin, the terms forecasts use, warning categories, coastal station reports, and a sample bulletin read line by line.

Pressure systems: isobars and what their spacing tells you, highs and lows and the circulation round each, how systems move, and a two-chart reading exercise.

Fronts: warm, cold, and occluded fronts with the sequence each brings, troughs, front symbols, and the passage of a low hour by hour.

Wind: the Beaufort scale, gusts and squalls, sea and land breezes, funnelling and headland acceleration, katabatic winds, regional wind regimes, named local winds, and the daily rhythm of the wind.

Sea state: fetch, duration, height and period, steepness, wind sea against swell, wind over tide and tidal gates, shoaling water, reading a swell forecast, and a worked sea state example.

Storms and heavy weather: how a gale announces itself, squall lines, the inside of a thunderstorm, tropical systems and season planning, and the preparation that matters when avoidance has failed.

Fog and visibility: the kinds of fog and how sea fog forms, what to do when visibility closes in, other things that reduce visibility, and cold and heat for the crew.

Charts and models: reading a synoptic chart, GRIB files, model runs, resolution and ensembles, reading a meteogram, and what a model cannot resolve.

Weather routing: what makes a weather window a window, the go decision as a set of questions, tactical routing, a worked passage plan with the arithmetic shown, briefing the crew, a passage plan form, and passages of more than a day.

Onboard instruments: the barometer and its trend, barometer rules and where they fail, wind sensors and calibration, true and apparent wind as a vector triangle, choosing weather apps, and receiving forecasts at sea.

Observing and logging: what to observe, reading the sky, cloud types level by level with drawings of each, halo and corona, an example log page from a passing front, and weather at night.

Coastal and harbour weather: choosing an anchorage for the weather to come, entrances, bars, and breakwaters, marinas.

Ten worked situations that put the whole book together, quick reference tables for use at sea, checklists for leaving, entering harbour, watch handover, and the start of the season, record logs, answer keys, and a glossary of forecast terms.

HOW IT IS BUILT

Thirty six diagrams and thirty nine tables, in clean black and white for print. One hundred and one review questions with answers at the back. Reference cards for your own forecast sources, vessel limits, and bolt holes, plus weather, forecast, passage, and instrument calibration logs.

WHO IT IS FOR

Skippers and crew of small craft, sail or power, who want to understand the forecast rather than just read it. No previous meteorology is needed. Terminology and warning thresholds vary between