Marine weather for Irish waters · Forecast by John Leahy
Forecasts daily for Dublin Bay, the Irish Sea, Ireland and offshore passages. For added interest, see below a set of quizzes for anyone who wants to understand the weather.
Each quiz is 5-10 questions, pitched where a sailor or a pilot actually needs to be: chart datums, tidal streams, air masses, the difference between what the barometer says and what the sea does about it. Every answer comes with the reasoning behind it. They take about five minutes, open on a phone, and keep working out of signal range.
From John's own book: the Hadley, Ferrel and Polar cells, why the Sahara sits where it does, where the trade winds and our south-westerlies come from, and why Ireland, at 50°N, is where two air streams collide.
Take the quiz →From John's own book, Weather-Wise for Sailors in Irish Waters: the Coriolis effect, why the sea holds 90% of the planet's stored heat, the Polar Front over Ireland, dew point, and the four ways air rises to form cloud.
Take the quiz →Sea fog against radiation fog, what "Fog" actually means on the Shipping Forecast, why a rising wind doesn't clear it so much as lift it, and the fog that catches a boat out coming home after a clear afternoon.
Take the quiz →What actually drives the breeze, why May and June beat August, the veer through the afternoon, why a light offshore gradient makes the sharpest front of all, and what a thickening sky does to your day.
Take the quiz →Gale warning timings, what the shipping forecast means by poor visibility, sea fog that will not blow away, wind over tide, and why a force 6 across the Irish Sea is not a force 6 in the Atlantic.
Take the quiz →Chart datum and charted elevations, the amphidromic point that flattens the tide off Arklow, the age of the tide, and where the stream runs to six knots at springs.
Take the quiz →Lapse rates and cloud base, what occlusion actually means, why the surface wind is not the wind on the chart, the anvil at the tropopause, and the difference between a squall and a gust.
Take the quiz →