Thorli - surf spot statistics

Best Surf Season (October – March)

The North Atlantic roars to life during these months, with average swell heights consistently above 2.4m and long periods averaging 9.8 to 11.7 seconds. Dominant swell directions from the SW, SSW, and S quadrants pound the Icelandic coast, and when a southwest wind sets in – the golden offshore here – Thorli transforms into a powerful, long-period playground. The climatological ramping up of extratropical cyclones across the North Atlantic drives this surge, bringing pumping head-high to double-overhead sets. Still, the window of perfect conditions is narrow: ideal wind only blows 11–14% of the time, so patience and a keen eye on synoptic charts are crucial to score the best days. When the low-pressure systems align with a stable high to the west, expect epic, heavy waves in the 1.5–2.5m range with periods over 10s.

Fair Surf Season (April – June & September)

As the North Atlantic storm track begins to weaken in spring, Thorli sees a gradual drop in average swell height, from 2.4m in April down to 1.5m by June. Wave periods also shorten, falling from 9.7s to 8.8s – still rideable, but lacking the raw power of winter. However, the percentage of ideal offshore wind rises to 19–38%, offering more frequent clean sessions. Swell directions remain dominated by the SW through SSE quadrants, with a notable increase in SE and SSE swell, which can wrap in nicely. The wave heights during this period are mostly in the fun-sized 0.5–1.5m range, perfect for groveling and turning tricks. September marks a transition month, with average swell climbing back to 2.1m and periods to 9.4s, while ideal wind drops to 22% – a taste of the coming winter.

Low Surf Season (July – August)

July and August represent the true summer lull for Thorli. Average swell heights bottom out at 1.4–1.5m, and wave periods stagnate around 8.2–8.5s – marginal for any real power. The swell is dominated by shorter-period windswell from the SW through SSE quadrant, mostly under 1m. On the bright side, offshore winds blow a generous 34–39% of the time, making for cleaner but smaller conditions. Expect micro to small, fun-sized waves (<0.5–1m) on most days. Occasionally a remnant groundswell from a distant storm can push in, but those are rare. This is the season for longboard cruises and fin-tuning your flow, not for charging.

September: Autumn Fire-Up with Expanding Windows

September signals the start of the autumn ramping: average swell height jumps to 2.1m and period to 9.4s. Swell is heavily focused on the SW (16.2%), SSW (11.9%), and S (8.6%) directions, with a notable increase in SE (6.9%) and SSE (7.1%) swell. The ideal wind percentage drops to 22% as the storm track becomes more active, but when the stars align, the quality is high. Wind from the N (8.8%) and NNE (8.5%) begins to increase, bringing more onshore days. However, the increasing swell strength means that even with less frequent offshore wind, the waves have more push. Look for post-frontal NW winds that groom the SW groundswell into clean, powerful lines in the 1–2m range. This is a transition month where a patient surfer can score both fun-sized and heavy sessions.