Sea condition forecast confusion
 

I used both swellwatch.com and windfinder.com to see if I should to fishing on my kayak. Many times the predictions are wrong (or I just don't know how to read them).

For example, last Sunday, swellwatch.com reported little swell (dark blue) for the Newport Beach Harbor Mouth area. windfinder.com also report waves around 2 ft and relatively low wind (5-7mph) for 6-9am period. When I got there though, the sea isn't calm at all. I paddled to the mouse opening and had to turn around cuz I didn't feel safe on my PA12.

Am I not reading the forecast right or am I missing something here?

Spring..they seem to get it wrong as much as right especially this time of year.

Hey Tommy,

It took me a long time to get the hang of the forecasts and you shouldn't expect to get it over night.

One of the most valuable things for me was to look at the forecast, go out and see what that looks like. Take a mental note.

Firstly, forecasts are just predictions of what will happen. Sometimes its spot on, sometimes it couldn't be farther from the truth. There is a certain margin for error that needs to be allowed.

Reading a forecast can be very tricky because there are A LOT of things to consider (multiple swell sizes, swell period,multiple swell direction, high/low pressure systems, wind, wind direction, current and). All these things will affect what the conditions will look like the next day.


So now to how different conditions effect the kayakability.

Swell Size - this is one of the least important aspects unless the forecast is over 3-4 ft. This is what will determine the rolling up and down motion of the kayak on the water.

Swell Period- This is very important especially for surf launches. this is how often the waves come in. This will determine how often you will go up and down. Low swell period can cause the water to have a sort of washing machine effect especially with different swell directions.

Swell Direction - this will affect in which direction the surface water will push you. Additionally if there are different swell direction from multiple swells - this can cause the water to have a washing machine effect.

Pressure Systems- Air pressure travels from areas of high pressure to low pressure. This is the main mechanism for air movement and this in turn creates wind among other factors. So knowing where the current pressure systems are can give you a better understanding of the weather/wind predictions posted and verify accuracy.

Wind/ Wind Direction - I think around 10 knots is when the water starts white capping. I personally go out if the forecast begins under 5 knots and off the water before it hits 10-15 knots. Depending on the direction of the wind this can either amplify or suppress some of the surface mess on the water. Offshore winds are warmer and generally soften the surface chop (to a certain point (under 10 knots)) and onshore winds are colder. Note that going out in offshore winds will push you offshore if the winds pick up too much.

Current - this can amplify the conditions on the water depending on the direction. This will also generally decide where your kayak is drifting and the speed at which you drift.

Hope this helps.

^^ nice break down!!

What Denis said. Great real-world explanation. For what it's worth, I also check weather.gov for NOAA information. I look at the detailed forecast as well as zone forecast for any place I'm looking at fishing. The zone forecast gives me a better idea of what's probably happening to the area as a whole so I can keep it in mind when looking at just the point forecast. But like was said, best thing is to know what the forecast said and go see what it looks like OTW.

Thanks for the tips Denis. Is 20 sec swell period good or bad for kayaking?

Good. For me anything under 10 seconds is seasick central. :ack2:

Good except for the fact that the faces on the breaking waves can be much much bigger with a long period swell.

Think wavelengths for sound.

20 second
.-*`*-..-*`*-..-*`*-..-*`*-..-*`*-..-*`*-..

vs

10 second
.-`-..-`-..-`-..-`-..-`-..-`-..-`-..-`-..-`-..-`-.

20 seconds is great for kayaking once your out on the water, but once again many aspects to consider. Like, are you shore launching, you will have more time to get out between sets. The downside as mentioned above is the face of the waves may be a bit bigger.

I don't like anything under 13 seconds. UNLESS the swell is 1 ft.

The longer the period the more power in a swell. Swell height is a different piece of the puzzle.
As stated, the more length between sets from the long (higher) period number the better.
So on 2-4' days and nights it really helps time the launches and landings.