How do I get accurate (or close) swell forecast/info for the Monterey Bay

Guys, I know the topic of swell has been covered ad-naseum on this site, and pretty much any kayak site. I have done a ton of searching, and reading but I still have questions.

Seems like what is ideal is a small swell with a long interval.  This seems pretty straight forward.  What constitutes a small swell?  I have been out when the forecast said 1-2 feet, and I have been out when it said 6-9 feet.  Obviously the 6-9 was quite a bit more of a "ride"  where is the recommended, don't go out there line for non crazy people?

Then you have the primary, secondary and so on swells.  I can draw some of my own conclusions here, such as if they are moving in the same direction as the primary swell, it could make the interval feel shorter, and if they are moving across the primary, seems like it would make it feel more choppy,  is that a correct conclusion?

And finally,  when looking at a forecast, how do I know which area they are talking about?

For example,  for this Sunday in Santa Cruz, 

Swellinfo.com has the primary swell forecast of between 6 to 8 feet at 13 seconds with a with a NE wind at 3 to 4 MPH in the morning switching to a SW swell at 2-3 mph in the afternoon.

NOAA has the forecast as S winds 10 to 20 kt with gusts up to 25 kt. Wind waves
3 to 4 ft. W swell 8 to 12 ft. Rain likely.

So those seem significantly different to me. Is this because they are looking at different spots, IE, one is looking closer to shore, and the other further out beyond the protection of the bay?  If I wanted to use one of these as my prediction for whether or not I should load up and try to go out,  which one should I look at?

Sorry if this is redundant,  I really did try to search and couldnt find the info I was looking for.

I'm no expert, but I've been looking at what buoy the data is coming from on swellinfo. There's a link to the buoy map and it seems pretty accurate if you're near the actual buoy.

I use windy.com check it out

Usually the generic forecasts are based on buoy location. I still like the NOAA point & click forecast because it provides a forecast for the exact spot you select by running the variables through a forecast model. Click wherever on the map then expand Detailed Forecast: https://marine.weather.gov/MapClick.php?lon=-121.90280&lat=36.90008#.XAmieBaIaEc

But one of my new favorites is this multilayered forecast model from Ventusky: https://www.ventusky.com/?p=36.76;-122.34;7&l=wave (checkout the pulldown menu for waves, wind, temp, etc).

When planning a trip, I check the marine forecasts for swell size & direction (and secondary swell size/direction), wind strength & direction, and tides. But I also look at surfing websites to gauge the surf. Because sometimes the swell & wind doesn’t correlate to the surf size. For example, a long-period south swell might be only 3-4ft @ 16secs offshore, which is relatively flat...but it could produce huge surf onshore because south swells often originate from the southern hemisphere and take longer to arrive at our coast...so they have gathered more strength and are moving much more water than a 3-4ft 16secs NW swell. Also, the longer the period the larger the surf will seem.
I avoid square days when the swell size is equal to the period, like 8ft @ 8secs.

This is an awesome site (links to actual forecast in here too) but this URL portion is "how to read charts" in Monterey

http://www.garlic.com/~triblet/swell/Inet1XMP.html

After you get your info from the sites suggested here, there's still that decision making process, here's one of the best threads on that from the past. 

http://www.norcalkayakanglers.com/index.php?topic=32677.0


For raw data tho, NOAA point and click is it.

https://marine.weather.gov/MapClick.php?lon=-121.87339782714844&lat=36.63095800819411#.XAnTJ9tKjIU
Most useful here for me is the hourly data graphs, look for them down below the point and click map.

...where is the recommended, don't go out there line for non crazy people?

You're not going to get a reliable answer to that here, as everybody on this site is at least fair-to-partly-crazy.

...where is the recommended, don't go out there line for non crazy people?

You're not going to get a reliable answer to that here, as everybody on this site is at least fair-to-partly-crazy.

Ditto... give credit to when credits do.

I use windy.com check it out

Yup

Long period swells make for a rough beach launches but are good out in the ocean.  The rule of thumb is the period is twice the swell.  4ft @ 8 seconds etc. is pushing my comfort level but I know I've been in 4-5 @ 8 seconds.  Wind makes things choppy or makes the waves stand up, and then a cross swell may cause chop.  10kts is my max time to get off the water but have muscled through some 17's in the opposite direction of the tide.  Not happy...I compare all my research to 4ft & 8 seconds and no more then 10kts then I compare that to how desperate I am to fish then hit the spot and make a decision.  You'll know when you get there.

Long-period swells don't necessarily cause long beach run-ups.  Sometimes they do, most often they don't.  It depends on whether the measurement is peak-to-peak into a headwind or peak to trough in a following wind.

NOAA's marine forecast is for the open ocean three miles and more from shore, and the buoys are located out past the three-mile line.  Surfing websites are for the surf line and what's happening beyond the breakers and out to the three mile line isn't their focus.  But these are the best tools we have if we aren't standing on a beach looking at the ocean.

Using NOAA's forecast, or the buoy data, or a surfing website is only going to allow you make general assumptions about what the conditions are where you'll be in your kayak, and the best assumptions are based on practical experience in that location.

You are correct that swells coming from widely different directions will cause the sea to feel choppy, but all swells coming from the same direction does not necessarily mean a smoother sea.  Consider a 3 foot primary at 10 seconds with a 2.5 foot secondary at 10 seconds.  They aren't always going to arrive together and you could find very short intervals between very similar waves.  All swells from the same general direction does mean that there will be times when all those swells are going to merge to create a significant swell, which is about twice the size of the most common swells.

It's a complicated web to unweave, but I have the advantage of living right on the coast where I can look at all the information on the web, then look at the ocean and see what it's really like out there.

Thanks for that.  That helps me.  I'm thinking the power of the wave created by a longer period depends on the contour of the bottom of the spot you are launching from and certainly the direction it is arriving from.

Thanks for that.  That helps me.  I'm thinking the power of the wave created by a longer period depends on the contour of the bottom of the spot you are launching from and certainly the direction it is arriving from.

Bingo! Now consider that the Monterey Bay submarine canyon is the largest/deepest underwater canyon along the west coast of N America. The head of the canyon is very close to shore, like 2 miles off Moss Landing. As large swells push into the bay, the canyon acts like a funnel. [same volume of water flowing through a narrower gap; water displacement needs to go somewhere] So, long period swells seem to have a greater affect on the surf height inside M bay than they do in other areas of the coastline.

Thanks folks.  This is helpful.  Appreciate the info.