No-Go Formulas??

[2000SR380]

Did not want to highjack the 'Neabsco to Somers Point NJ' thread, but it got me thinking. What do you guys use as a go/no go criteria? I realize that boat condition, size, and type, along with the captains experience and the crew's tolerance will all factor in, but do you guys have a basic formula? For instance : I do not like square waves 6ft swell on 6 seconds is going to be steep and rough. 6 foot waves on 9 seconds and I can travel on plane with a pretty smooth ride. I like the basic formula that if the swell interval is 3 more than the swell height, the wind is less than 20 knots, and the wind waves are less than three feet, you are typically good to go. There are notes of course such as a 15 ft wave on 20 seconds is reasonably comfortable off shore, but can create havoc crossing a bar, or inlet, and warrants extreme caution when close to the shore or shallower water. The closer to no-go I get the more I prefer to go down wind and avoid beam seas. Lightening is a full on 'stay tied to the dock' for me, don't care about rain.

 

[ttmott]

Actually for me it's a combination of things. First your boat's capability. Second, your capability and what you are willing to put yourself and crew through from a comfort aspect; safety always first consideration. And last but most important is predictive analysis; ie, what is the weather and sea situation predicted to be when you are out there until back to safe harbor. So, is there a "formula"? No not really, it's an analysis of the variables and predictions but also that gut feeling or what I call "the pinch" and over the years I've learned to listen to the pinch. I make five or six crossings to the Bahamas a year and this works for me. And, for the record, I simply don't have any desire to get out there with anything over 4's....

 

[k9medic]

My formula is simple. If it's not forecasted to be nice I just don't go. I do this for relaxation not for work. The caveat to this is if there is rain. I have headed out in a rain storm knowing I would be offshore and the weather would be clearing.

AS was mentioned earlier, "squared waves" over 4' for me is a deal breaker.

 

[rcknecht]

Small Craft Warnings; Gale force winds; torrential rain; wave height above 5' = NO GO
Intercostal through certain areas at low tide = NO GO
Anything Else = Go

 

[HUMPH]

Good thread, makes you think a bit more. On the river it's anything over 20 to 25 knots, just no fun. One caveat is if I have a planned trip I need to get to gets me out of my slip until about 30 knots. The bay brings different challenges and I am at the mercy of timing. I may leave in good conditions and arrive in slop! The ocean is as you stated.

 

[northern]

When we go to Alaska there are two open areas. On 50 miles the other 70 miles. As they say look west and you can see Japan. We like 3 to 5 foot rollers as good. If the tops are blowing off them we do not go. With wind we like 15 knots or less but have gone in 20 knots. If you go in 20 knot winds and 5 foot swells it will get worse. Last summer we went in calm then half way across we got 8 foot waves and swells with the tops blowing off them. It is not pleasant. We always secure the boat for rough water. That is if it will fall put it on the floor, put loose kitchen items in the sink and make sure all items on the decks are tied down.
So the short answer is go in what you feel comfortable not what others say is good. Last summer people we know went in big winds and high waves in a 27 footer. They go fast. If they went slow they would probably plow into the waves and put the front deck under water. Any way the waves were so bad the ponding knocked out their electronics. They made it but it sounds like that is the last time they will feel they are big boat people.

 

[2000SR380]

If you go in 20 knot winds and 5 foot swells it will get worse. Last summer we went in calm then half way across we got 8 foot waves and swells with the tops blowing off them. It is not pleasant. We always secure the boat for rough water. That is if it will fall put it on the floor, put loose kitchen items in the sink and make sure all items on the decks are tied down.
So the short answer is go in what you feel comfortable not what others say is good.

Ken alluded to one of your good points as well 'it will get worse'. You can leave in flat conditions and they can build into less fun conditions. I use The Weather Underground and our regular local weather guys to determine max conditions possible. Wunderground.com has been a consistent resource for me and years of experience allows me to interpret how their forecasts transfer into actual conditions. ( I think whatever forecast format you like use the same one every time). On the West Coast we have an afternoon wind machine, so Pacific Coast transit in power boats is best done in morning jumps if predicted conditions are iffy. Once out there it is all about "the pinch" as described by ttmott.

 

[Gofirstclass]

For us river boaters the rule for me is -- if the wind is going to make getting into the slip/dock/lock very difficult, we don't go. Usually that's a wind above 25kts, but that depends on the direction it's blowing from.

When I helped that guy take his boat from Seattle to Stockton 3 years ago the reason I volunteered was to get ocean water experience. I now know a LOT more about open water than I did before the trip.

Here's a video I shot on the worst water day. It was also the most fun day of the trip, once I got rid of breakfast! :wow:
[video=youtube;uKgc8DBUi8M]https://www.youtube.com/watch?v=uKgc8DBUi8M[/video]

For open water cruising I'd say that if the wave height/interval are a box, that's a no-go. Also if the winds are blowing the tops of the waves off on most of the waves, that would be a no-go. On that trip to CA we stayed in port a few extra days because two of us voted not to go out. Majority rules.

 

[SR400DB]

This is an interesting thread.

Back in 2003 we took our boat down the coast from San Francisco and into Mexico where we spent the winter. Back then there were far fewer areas to access good real time and future cast weather data. We made the trip down to San Diego in three days. The return from San Diego to the Golden Gate was then made in two days. Both times we lucked out and could have water skied the entire trip (average speed during daylight was 24.2 knots). Weather was obtained from NOAA broadcasts and limited buoy data. At this time, I knew nothing of Grib files and other resources. To say I was naive was an understatement!

Fast forward to 2013 (Fall of). We had finally gotten everything to fall in the place for our trip from San Francisco to Seattle. This a much different beast than harbor hopping South and was not to be taken lightly. Going North, there are longer legs without fuel and shelter until you reach Coos Bay, Oregon. We had a couple of rules, one we did not leave port with squared off or greater swells to frequency. If the wind was greater than 20 knots, we stayed in port. And, lastly, if ANYONE voted to stay in port we did.

For the weather data, we did a few things:

1. Current conditions outside the boat.
2. Grib files were downloaded twice a day for current and future-cast wind predictions.
3. Real time swell and sea conditions from NOAA buoy data.
4. We closely monitored the harbor conditions at all locations North of our position. As the conditions deteriorate, the harbors will begin to close to recreational (and at times commercial) traffic from North to South. Then, as conditions improve the harbors will open in the same pattern. Once the harbors/bar crossings began to open North of our position, we very closely monitored the wind first, then the sell conditions to make a run for the next port.


Our general rule was swell at 6' or less with 8 seconds or greater (preferred) frequency; and wind less than 20 knots. We did poke our head out of Newport Oregon with sea conditions a bit more than that and winds a bit higher than 20. We quickly made the decision to return to port. We grabbed some more sleep for about 7 hours, left port at 0130 and found conditions very much to our liking.

This trip was about 1,000 miles start to finish, took exactly seven days. Two and a half of the seven were spent in Newport, Ore. waiting on conditions to improve. We made two 48 hour runs, averaging 9 knots for the duration of the trip.

The thing I learned the most from this trip was to watch the wind far more than the swell and sea state. It is very rare to have rough seas with little to no wind. But almost a guarantee to have terrible conditions with high winds. Even our threshold of 20 knots may be a bit high for most voyages. Like I said, rule number one was to go outside and take a look and examine the current conditions at our location.

 

[sbw1]

Forecast for our destination and along the way drives our decision. Wave hights in a head sea three feet or less. Winds 15 knots or less if on the nose or quartering on the bow. 25 knots if on the beam or stern. Wave hight 3-5 feet on the beam or stern. Rain is no problem unless it is result of a thunderstorm. Thunderstorms are ok if they are the result of a squal line and will be through an area by the time we plan to arrive. Scattered thunderstorms are ok if they are isolated and not in a line we will transit. Temperature is not an issue for us from April to October as our helm is a controlled environment. We do consider conditions at the arrival harbor. Water breaking over a wall is ok if the channel is wide. A place like Grand Have is ok. A place like Port Sheldon is too narrow and not fun. Now that we are retired, we are much more conservative about travel conditions because we do not have to be someplace the next day (work).

Our boat has seen some of the poorest weather conditions you can imagine, largely as a result of weather surprises. We have also crossed 110 miles of open water when we could have water skied the entire distance. That is the ideal, but mostly we travel in 1-3 foot seas from the south west or north west since prevailing conditions favor those kinds of seas. Lake Michigan and Lake Huron are seldom flat.

 

[FootballFan]

I really like the user interface on windyty.com. Typically look at a couple or more weather sources.