Sea conditions after a front passes -- any real world experiences?

[Bene505]

When you are out in the open as a storm hits you, I can understand that the sea state can get very large, with wind waves on top of pre-existing swells.

What is it like once the front has passed? Does the shift in wind associated with frontal passage result in higher waves due to the wind being against the waves? Or it is more a confused sea which is not as bad as what you just went through in the storm?

[GeorgeB]

Let’s see, real world experiences – you don’t want to hear about any virtual or imaginary experiences? Oh well. Being from California I can only speak for the Pacific and your trip to Bermuda probably has a whole different set of weather patterns. I am most familiar with conditions after fronts have passed through. Obviously, right after a front has passed, the ocean can still be a bit boisterous. As the high fills in, the winds pretty much shut down to light breezes. The wind wave settles down within a few hours and the wave periods lengthen and the crests aren’t as peaked but they still can be pretty high. We call this a leftover sea out here and usually the discussion centers around, “this sucks, we should have been racing yesterday”. If a crewmate has any propensity towards seasickness, this is the time you will find out. It takes about four days for a front to cycle before the pattern repeats itself. If the high fills in and parks over you, you’re screwed. The ocean goes to millpond smooth and you start to recalculate your fuel reserves. In the trades, squalls will have the same effect. Winder than heck during the storm and if you exit directly behind it, you will have hours of no breeze at all until the next one hits or until mid morning, which ever comes first.

[Maine Sail]

What George said but I'd add that up here the wind tends to die off quite rapidly leaving you with confused lumpy seas of the sail snapping type.. Our fronts are usually not too wide in mileage scope so you could be five miles away and never even get wet but could see it in the clouds and rain in the distance.

We got stuck in a micro burst about 8 years ago anchored at one of the of shore islands. Four boats went on the rocks and lots of trees were down. Within a half hour it was glass again.. Less than a mile away on another island there was still laundry hung on a line..

I think it depends on the front and where you are... In the open ocean I worry a lot less about the front than the lightning.. 40-50 knots for 20-40 minutes is still small seas. 40-50 for two days is a freaking nightmare with any sort of fetch...

[smackdaddy]

Maine - let me pipe in here with the obligatory stupid question...

Lightning. What the hell do you do out on the water for that? I've been reading and reading and still haven't come across a discussion of this.

BTW - Bene, the CRAZIEST sea state I've come across is in "Desparate Voyage" by JC. When he was in the eye of a hurricane, he described the seas as being so insanely confused they were "pyramiding" - that is absolutely no wind, but the waves would all meet and shoot straight up 30-40 feet. That's gotta be hell right there.

Oh - REAL WORLD experiences....ahmm...I got nothin'. I sail in a puddle.

[Ilenart]

Bene,

my experiences mirror Georgeb & Mainsail, blows like anything for 10-15 minutes then eases off rapidly.

For further details the book Surviving the Storm by S & L Dashew contains about 20 references to "frontal passages" including a number of first hand accounts that they reference.

Ilenart

[Bene505]

(Thanks Smack, that was very enlightening. Wow!)

Originally Posted by Maine Sail

...40-50 for two days is a freaking nightmare with any sort of fetch...

And what's that like afterward on the open ocean? I'm guessing that the wave height is still there, but they are less steep. But I wouldn't know.

[Bene505]

And a specific question for the east coast of the US... can you follow a really big storm out to sea? Or will it just be too nasty?

[sailingdog]

I think it really depends on what kind of storm you're talking about too. A summer thundersquall line generates some pretty nasty winds...but it doesn't generally last long enough to cause much in the way of waves.

Other storms last a lot longer and cause much more in the way of waves, and can cause some seriously confused seas, especially if the wind shifts direction dramatically.

Also, the strength of the rain can affect the waves. Really heavy rainstorms tend to flatten out the seas from what I've seen.

[camaraderie]

Bene...you CAN follow a frontal system that comes off the continent and moves out to sea after it has truly passed and the wind has shifted. The only caveat is that if you will be crossing the gulfsteam...you really need to make sure that 24 hours have passed since the front has passed (assuming north winds after a frontal low off the east coast) as the stream takes a while to settle down after stong winds have oppsed the current for any length of time.
I am referring to frontal systems here...not following brief squalls.
Obviously the boat and the captain should look at the predicted wind and sea state for after the front before leaving port but unless you are talking about something really massive that hangs off the coast...leaving after a front can get you south without having to beat into the prevailing high.

[paulk]

We sailed from Bermuda to New York the week after the Bermuda Race earlier this summer. (June/July 2008) The Bermuda Weather service predicted a front approximately 500 miles long that would come off the US East Coast and then sit on top of and essentially parallel to the Gulf Stream for a couple of days before being pushed north. Forty-five to fifty knot northerly winds were predicted along the front. The wind, blowing counter to the current in the Gulf Stream, was expected to build 20-40' waves in some areas. We set out on Saturday, hoping that the front would blow off before we got there. It did not. As we approached the Gulf Stream, we could see the line of high-altitude thunderheads stretching from about where we were to as far north as was visible. We decided not to knock ourselves out, and slowed the boat by strapping in and pinching to about 2 knots for about 12 to 18 hours, to give the front time to move on. Others thought they were tougher than we were. We heard over the radio afterwards that three boats had injured crew heliported off, because they had sailed right into the conditions predicted by Bermuda Weather. We watched the clouds slide north, and ended up crossing the Gulf Stream with clear blue skies, in an essentially smooth sea, under power for about half a day because the wind had dropped to less than 8 knots. It picked up afterwards, and we managed to arrive at New York Harbor the morning of 04 JUL. Going up the East River with the tide we hit 13 knots over the bottom. Avoiding fronts is much more relaxing than running into them.