Weekend Surf Forcast - 17th - 19th March

Report Date: Friday 17 March 2017

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Summary

Consistent medium sized swell, bigger and windier in the north

Best bet

Portugal

Synopsis at 00:00 UTC

Today’s chart shows a large anticyclone just north of the Azores, gradually weakening and shrinking south. To the north there is a centre of low pressure southwest of Cape Farewell, moving east and deepening slightly, expected over Iceland by Sunday, and another system off Norway, disappearing quickly. A moderate to strong westerly flow exists across the middle of the North Atlantic, generating some swell for west and northwest exposures. The upper airstream is fairly straight, with moderate north-south pressure gradients. Local pressure gradients are strong in the north, weak in the south.
NAO index (large positive values usually mean potentially good surf): +30 mb

Area forecasts

Southwest Wales

Friday:
Lumpy wind-driven swell, picking up to six feet or more at exposed spots by afternoon, with strong westerly winds, gusting gale force later

Saturday:
Continuing largish and very lumpy, around six feet or so at exposed spots, with strong westerly winds

Sunday:
Continuing almost unchanged, around six feet and stormy, with strong gusting gale-force west-southwest winds

North Devon and Cornwall

Friday:
Long-period swell, gradually becoming swamped by windseas, up to six feet or more at exposed spots, with strong westerly winds

Saturday:
Largish, wind-driven swell, exceeding six feet at exposed spots in the west, with strong perhaps gale-force westerly winds

Sunday:
The swell becomes a bit more solid, perhaps reaching eight feet at exposed spots in the far west, continuing lumpy with strong west-southwest winds

South Coast of England

Friday:
Long-period swell, around three feet at westerly exposures, with lumpy conditions in fresh becoming strong west-southwest winds

Saturday:
Any remaining swell is replaced by short-period windseas, up to three or four feet at exposed spots, with fresh to strong westerly winds

Sunday:
Wave heights drop to around three feet at exposed spots, and winds gradually back to fresh or strong west-southwest

East coast of England

Friday:
Very small or flat in most places, with strong gusting gale-force west or southwest winds

Saturday:
A good-quality north swell arrives, around three or four feet at northerly exposures, with fresh gusting strong westerly winds

Sunday:
The north swell continues, averaging around three or four feet, with fresh gusting strong perhaps gale-force west-southwest winds

North Coast of Scotland

Friday:
Largish west-northwest swell, mixes with a northerly component, up to eight feet or so at exposed spots, with bumpy conditions in fresh westerly winds, veering northwest later

Saturday:
The west-northwest swell decreases and the northerly component continues, around five or six feet on average, with lumpy conditions in strong westerly winds

Sunday:
Winds pick up to gale-force westerlies, and any remaining swell is swamped by local windseas; wave heights exceeding eight feet by late afternoon

Northwest Ireland

Friday:
Large, poor quality swell and windsea, well over ten feet at westerly exposures, smaller elsewhere, with gale-force southwest winds veering west during the day

Saturday:
The swell weakens, but still reaching ten feet at westerly exposures, smaller elsewhere, with strong gusting gale-force westerly winds

Sunday:
The swell becomes a bit more solid again, exceeding ten feet at first before dropping steadily, with strong westerly winds

Southwest Ireland

Friday:
Large, wind-driven swell, hitting 15 feet at exposed spots in the afternoon, with strong to gale-force southwest winds

Saturday:
Wave heights drop to around 12 feet or so by afternoon, and conditions remain extremely lumpy, with strong gusting gale-force west-southwest winds

Sunday:
Another pulse of swell arrives, perhaps hitting 15 feet again in the morning before dropping gradually, with strong to gale-force west-southwest winds

Southwest France

Friday:
Solid long-period swell, around six to eight feet, hampered by light to moderate winds from a westerly quarter

Saturday:
The swell drops to around five or six feet, and conditions are fairly clean in the morning, with light or moderate north-northwest winds in the afternoon

Sunday:
The swell continues, with a new small long-period component, around six or seven feet, with windless conditions at first then light or moderate north-northwest

North coast of Spain – east of Gijón

Friday:
Good long-period swell, around six to eight feet, perhaps bigger at exposed reefs, but hampered by moderate northwest winds

Saturday:
The swell weakens and drops to around six feet, with windless conditions at first picking up to light then moderate northerlies during the afternoon

Sunday:
Wave heights pick up a bit, perhaps exceeding six feet at exposed reefs later, with light becoming moderate or fresh northeast winds

North coast of Spain – west of Gijón

Friday:
Good-quality northwest swell mixed with shorter-period northerly components, up to five or six feet at exposed spots, with light then moderate or fresh northeast winds

Saturday:
The swell becomes less mixed, around five or six feet at exposed spots, with light becoming moderate or fresh northeast winds

Sunday:
A new longer-period component arrives in the afternoon perhaps pushing wave heights over six feet at exposed spots, with light then moderate or fresh northeast winds

Northwest Galicia

Friday:
Average quality west and northwest swells, around six to eight feet at exposed spots, with fresh to strong northeast winds

Saturday:
The swell continues, swinging more northwest overall, around six feet or so with fresh gusting strong northeast winds

Sunday:
A new west swell arrives mixed with the existing swell; wave heights exceeding six feet at exposed spots, with fresh northeast winds

Portugal – north of Lisbon

Friday:
Good-quality northwest swell with a small westerly component, around six to eight feet but bigger at swell-magnets, with fresh easterly winds, swinging north later

Saturday:
The swell weakens but still doesn’t drop much below six feet, with moderate easterly winds at first then moderate or fresh northerlies in the afternoon

Sunday:
A new long-period west swell arrives, well over six feet at exposed spots, with light northerly winds picking up moderate to fresh in the afternoon

Portugal – south of Lisbon

Friday:
Good-quality northwest swell, up to six feet or so at northwest exposures, with moderate easterly winds, decreasing and swinging north in the afternoon

Saturday:
The swell weakens, down to four or five feet at exposed spots, with moderate northeast winds backing north by around midday

Sunday:
A new long-period west swell, exceeding six feet at exposed reefs, with light northeast winds early morning becoming moderate northwest by afternoon