Coastalwatch Surf Forecast - Feb 16th 2012

February 16 2012 | Posted in Forecast

Short Forecast:

Low scale ESE swell mixing with NE windchop 1 - 2ft. WIND: Early light N 5 to 15 knots tending NE 15 to 20 knots during the day.

ENE swell 1 to 2ft max and small SSE swell speculatively increasing to 1 - 2ft into the afternoon. WIND: Early NNE 10 to 20 knots tending S 10 to 20 knots during the day, tending light SE later.

SSE swell speculatively increasing from 1 – 2ft early towards 2ft+ during the afternoon. WIND: S 5 to 15 knots tending SE to NE during the afternoon.

SSE swell 1 - 2ft+. Early SW winds tending SSE during the day.

Forecast Overview

The high pressure system located over the southern Tasman Sea persists as the dominant influence on conditions; maintaining calm, sunny weather across the coast on Thursday, while having a firm suppressing influence on wave activity across our swell window. Although we’ve been pinning hopes of some new NE windswell for Friday arising from a strengthening northerly flow developing down the NSW coast on Thursday afternoon, this swell source is a little too localised to generate any notable new windswell.

Instead we continue to rely on residual SE swell and background E tradewind swell to maintain slightly smaller surf on Friday. With any luck Manly’s excellent exposure to this part of our swell window should see contestable, one to occasional two foot waves hanging in through Friday and Saturday.

The outlook for Sunday continues to hinge on a trough and cold front sweeping across Tasmania on Saturday night and out across the Tasman Sea on Saturday. The trough extends a weak southerly change across Sydney just around mid morning on Saturday, but winds should ease and turn light SE during the afternoon.

At this stage there are still some inconsistencies among key models casting doubt over precisely how the cold front and anteceding ridge will impact our swell window. This specifically surrounds the projected strength, duration and alignment of a SSE fetch developing across the southern Tasman on Saturday. Although some recent modeling aimed a narrow, 20 to 30 knot belt of SSE winds our way throughout Saturday, latest model runs are heavily downplaying the strength and duration of the fetch; indicting the trough will rapidly weaken as it moves out across the southern Tasman Sea -  effectively dividing two dominant high pressure systems  occupying our swell window;

Hence, the prospect of any substantial increase in SSE swell on Sunday is tenuous; perhaps increasing to one to two feet. This will inevitably become clearer as the system begins to cross Tasmania in the next 24 to 48 hours. Beyond that, there’s likely to be small increase in S swell by Monday – originating from a Southern Ocean low traversing deep beneath Tasmania on Friday. Again, this is only expected to push in at one to two feet at Manly. I’ll update on this again later on Friday.