The year in Nouvelle-Aquitaine, month by month
The month-by-month figures come from Bordeaux-Mérignac, 1991–2020 series: 924.9 millimetres a year over 122.5 days and 2,083.6 hours of sun. They are contrasted with Biarritz-Anglet, on the Basque coast, and Limoges-Bellegarde, at 402 metres inland, which mark the region's two extremes.
Nouvelle-Aquitaine is France's largest region, at 84,061 square kilometres: bigger than Austria. Speaking of its climate in the singular is convenient and false, and the mistake is paid for in the suitcase.
Comparing two cities on the same coast is enough to see the size of the difference.
01 Nine hundred and twenty-five millimetres against fourteen hundred and seventy
The 1991–2020 series from Bordeaux-Mérignac airport, at 47 metres, gives 924.9 millimetres of rain a year over 122.5 days. The Biarritz-Anglet one, at 69 metres and on the same Atlantic front, gives 1,473.6 millimetres over 141.1 days.
That is 549 millimetres of difference, almost sixty per cent more, between two points about two hours apart by car. The cause is visible on the map: the Pyrenees. Damp air arriving from the west is forced to rise against the range and dumps before crossing it.
And the effect shows in sunshine: Biarritz adds up to 1,920.6 hours a year against Bordeaux's 2,083.6. The city further south gets less sun than the one further north.
Five hundred and forty-nine millimetres more water and only nineteen more rainy days: it does not rain more often, it rains harder.
02 The difference is not in the days, it is in the intensity
The comparison of rainy days is what makes the figure interesting. Bordeaux has 122.5 rainy days a year; Biarritz, 141.1. Only 18.6 days more, fifteen per cent.
Divide the water by the days and you get the explanation: in Bordeaux some 7.5 millimetres fall per rainy day; in Biarritz, some 10.4. Almost forty per cent more water in each episode.
For the traveller that changes the type of clothing more than the quantity. On the Basque coast it does not rain constantly: it rains hard for a while and then clears. A serious rain jacket works; an umbrella, with the Atlantic wind, almost never.
03 November rules across the whole region
What the region's three corners do share is the calendar. In Bordeaux the wettest month is November, with 114.5 millimetres. In Biarritz, November, with 206.9. In Limoges, November, with 106.1.
And the driest month coincides too: July, with 48.6, 77.3 and 62.5 millimetres respectively. It is the pure Atlantic pattern, maximum in autumn and winter and minimum in summer, precisely the opposite of the continental regime of much of Europe.
The bottom of the year is December for another reason. Bordeaux records 83 hours of sun in the whole month, that is, two and a half hours a day. January adds 86. Between them they total less sun than July alone, which gives 276.
04 And the interior, which plays another game
The region's third corner has nothing to do with the coast. The Limoges-Bellegarde station sits at 402 metres, and that is enough to change the whole year.
In January the average maximum is 7.2 degrees against Bordeaux's 10.5 and Biarritz's 12.2. In July, 24.2 against Bordeaux's 27.1. And in August, 24.4: three point two degrees below the regional capital.
Total rainfall is intermediate, 1,018.0 millimetres over 133.7 days, but sunshine resembles the Basque coast's more than Bordeaux's: 1,922.0 hours a year. That is, in the inland half of Nouvelle-Aquitaine it is cooler and cloudier, without raining much more.
05 The summer, which is short and very good
All the above is offset by a summer that is objectively good. From May to September, Bordeaux moves between 48.6 and 81.2 millimetres a month, between 7.0 and 10.0 rainy days, and between 207 and 276 hours of sun.
Temperatures play along without overdoing it: highs of 21.7 degrees in May, 27.1 in July and 27.6 in August, with lows between 11.4 and 16.3. Those are five consecutive months in which weather stops being a planning factor.
It is worth bearing the extreme in mind, though. The absolute heat records of the two coastal stations are from June, not August: 42.5 degrees in Bordeaux and 42.9 in Biarritz. Heatwaves arrive here earlier than the rest of the calendar would suggest.
06 How to choose the month
If the trip is coast and beach, June to September without argument. July is the driest, sunniest month of the year — 48.6 millimetres and 276 hours of sun — and August the hottest, with average highs of 27.6 degrees.
If the trip is inland, about vineyards or villages, September is the well-rounded month: 207 hours of sun, highs of 24.2 degrees and the grape harvest under way. Rain rises to 81.2 millimetres, but it is still a nine-rainy-day month.
And if you can only go in winter, choose the north of the region over the Basque coast. Between November and January Bordeaux collects 86.9 to 114.5 millimetres a month; Biarritz, up to 206.9. Almost twice the water for the same trip.
The year's four stretches
From 48.6 to 81.2 millimetres a month over 7.0 to 10.0 days, with 207 to 276 hours of sun and highs of 21.7 to 27.6 degrees. Five straight months in which weather stops being a factor.
83.3 millimetres over 10.7 days and sunshine falling from 207 to 165 hours. Highs of 19.6 degrees. It still works, but the margin narrows every week.
From 86.9 to 114.5 millimetres a month in Bordeaux and up to 206.9 in Biarritz, with sunshine between 83 and 103 hours, under three and a half a day. Highs of 10.5 to 14.1 degrees.
From 63.3 to 75.6 millimetres over 10.1 to 11.2 days, with sunshine rising from 109 to 190 hours and highs from 12.0 to 18.0 degrees. March is the second driest month on the calendar.
