Summary:

Thursday has medium and fading E swells from the Azores low with long period SSE forerunners from Earl growing to large levels with bigger size at dark. Friday has rapidly increasing S/SSE swells with tropical storm conditions and Saturday has Giant to medium S/SSE swells that fade with large to small levels on Sunday.  Please visit the Tropical Update for a complete tropical update.

Current Conditions:

Updated 8PM September 1st 2010...

Weather...Sensible weather with general offshore flow and afternoon SW seabreezes for 1 more day.

Waves...Small ESE swells fading with longer period S swell growing.

Daily Wave and Wind Forecasts:

Forecast Legend

Updated 8PM September 1st 2010...

2 Thursday -
East of Portland - Medium long period E swells fades with SSE swell building with light S winds.
Cape Ann to Portland - Medium long period E swells fades with SSE swell building with light SW winds becoming S.
South Shore to Cape Ann - Medium long period E swells fades with light SW winds.
Cape Cod - Medium long period E swells fades with SSE swell building with light SW winds.
S of Cape - Small E to SE long period swells fade with SSE swell building to large levels with light SW winds incereasing.

3 Friday -
East of Portland - Small long period S/SSE swells rising to large levels with light SE winds.
Cape Ann to Portland - Small long period S/SSE swells rising to medium levels with chop with light SE winds increasing.
South Shore to Cape Ann - Small E/SSE swells with medium NE chop with light NE winds increasing mid-day.
Cape Cod - Medium S swells grows rapidly with E chop building with light NE winds veeering SE and increasing rapidly.
S of Cape - Large S swells grow rapidly to extra large levels with light SE winds veering NE and increasing rapidly.

4 Satuday -
East of Portland - Large SE swells (west) and Giant S swells (east) and fading late with strong NW to moderate W winds (winds likely to be stronger as you head east, possibly very strong!)
Cape Ann to Portland - Large S to NE swells fades with 8-16 second period with moderate NW winds shifting SW late.
South Shore to Cape Ann - Medium refracted S swells with strong W winds becoming moderate W.
Cape Cod - Giant S and E swells with high energy levels with strong W winds becoming moderate SW.
S of Cape - Extra Large S swells with Giant AM sets fade all day but sets remain with moderate W winds fades late.

5 Sunday -
East of Portland - Large S swells quickly drop to small levels with sets remaining with almost moderate SW winds.
Cape Ann to Portland - Medium SE swells drop to small levels with almost moderate SW winds.
South Shore to Cape Ann - Small refracted SSE swells become tiny with almost moderate SW winds fading.
Cape Cod - Medium S/E swells drop to small levels with moderate SW winds.
S of Cape - Medium S swells drop to small levels with mpderate W winds.

Collaborative Forecast Discussion:

Updated 1PM August 27th 2010...

Mid-Latitude Sources:

On Friday High Pressure centered over Ohio ushers in NW flow and any leftover easterly swells will be biggest in the morning and smallest at dark (fading to tiny size), however local winds should be predminately offshore with a likely mix from NW to SW as daytime heating may induce local thermal winds. On Saturday High Pressure is centered over Philadelphia and Sunday is centered over Virginia and on Monday is centered over West Virginia as well as on Tuesday. The chance of a backdoor cold front seems less likely so high pressure remains the status quo for Wednesday into Thursday. By Friday a front is expected to sweep thru the region which will rotate winds to a SW flow and then back to NW for Labor Day Weekend.  It is just during hurricane season that we can take the idea of high pressure with light local winds and spin it into complete optimism!!! Unless radical changes in terms of mid-latitude flow, this part of the discussion will not be updated until a sensible change is required.

North Atlantic Sources:

The expected Azores low pressure is in full effect and the ascending ASCAT pass ASCAT pass does a marvelous job of showing the fundamental difference of a baroclinic system (Azores low) and a barotropic system (Danielle) in the sense that the radial coverage of gale force winds for the Azores low is many times the size of a tropical system. However, this does have a further travel distance so more of the energy will dissipate but on the uplifting note this provides a similar period swell with a Easterly angle which will have a moderate impact on filling in swell to most areas and the inevitable wave-wave interaction of constructive and destructive interference will lead to some unusual sets and higher than normal rip tides for easterly exposed coastlines. Currently we have a 984MB low pressure at 42N and 32W with a 1024MB high pressure to the north. A 40MB difference without evening seeing ASCAT data supports intense gale force winds. This low pressure is expected to remain in the same place as 2 areas of upper level energy provide reinforcing instability and eventually the system wil become vertical stacked by Sunday. During this time, expect 20-25 foot seas aimed directly at New England to develop along with captured fetch. By Monday this system retrogrades and lifts to the NW. Expect to see long period surf from an easterly direction to arrive on Monday and be completely overshadowed by Danielle, however on Tuesday as the Danielle swell fades expect to see this easterly swell become more noticable and last into Wednesday. Size wise, about 1-4 feet of 12-15 second period E swell so for best spots that is almost large sets and for protected coastlines it will be just small size but enough to add to the remaining swells from Danielle to make flatness a thing of the past. Thursday will continue to have leftover inconsistent swells.

Tropical Sources:

Please visit the Tropical Update for a complete tropical update.

South Atlantic Sources:

No swells from this region for the foreseeable future.

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