Where to Look for Ocean Temperature and Conditions?

[ATJ]

The problem with SST is it often does not reflect the temperature at depth.

Here off Sydney, even though it is the middle of summer, we are experiencing a run of NE swells. These swells cause the water temperature at depth to drop a lot.

For example, MagicSeaweed tells me the water temperature is 23ºC however for my last few dives it has been 15ºC at 10m and deeper. No site is going to give you that information, only other divers.

Edit: I missed Michael's post above saying basically the same thing!

 

[scuba5150]

I find MSW to be very accurate and helpful. Their water temp reports usually correspond with my computer and their wave/swell forecasts are very accurate as well. Of course the water temp will change as you descend and of course sometimes you'll run into thermoclines, but that's to be expected.

 

[tursiops]

I'm sure Magic Seaweed is helpful to surfers, for whom it is designed.
It seems extremely limited in coverage, and also is quite opaque about where it gets its data, thus there is no way to estimate its reliability or accuracy. Some of you say it agrees with your experience, and then complain it doesn't tell you want is below the surface. Well, no, of course it doesn't, none of the sites do. Thus my comment about subsurface temps in post #5.

Sorry, but reports from random divers can easily be off by 4 deg F or more, because of PDC inaccuracies and time constants. Not to mention the vertical profiles of temperature.

 

[noserider]

I'm sure Magic Seaweed is helpful to surfers, for whom it is designed.
It seems extremely limited in coverage, and also is quite opaque about where it gets its data, thus there is no way to estimate its reliability or accuracy. Some of you say it agrees with your experience, and then complain it doesn't tell you want is below the surface. Well, no, of course it doesn't, none of the sites do. Thus my comment about subsurface temps in post #5.

Sorry, but reports from random divers can easily be off by 4 deg F or more, because of PDC inaccuracies and time constants. Not to mention the vertical profiles of temperature.

Magicseaweed along with most other surf forecast sites use the same data sources NOAA etc and then they have their own algorithms to generate local wave forecasts at a beach level, which can be a little hit or miss due to local wind, topography, beach angle, tides etc and thus most surfers learn how to interpret MSW forecasts into more accurate local forecasts.

However for open water swell it is very accurate however you do need to dig a little deeper into the site to pick up all the swells and often the second or third swells are the ones that water users are interested in rather than the primary swell, which can often be short period.

I am unsure how accurate it will be for temperatures as the only data it will get is surface temperatures from buoys and like you say it was not designed as a tool to measure sea temperature at the surface let alone at depth

 

[ATJ]

I find MagicSeaweed invaluable for planning my (shore) dives around Sydney. For Australia it gets its data from Australian Bureau of Meteorology.

The information I use is the swell direction and height. This tells me whether entry/exit at a site will be easy/difficult/unsafe but also gives me some indication as to surge, etc. It doesn't matter if it is not 100% accurate as I just need to know the approximate swell direction and height.

I can't comment about other location but for the locations I use it, it gives me the information I need and has proven reliable for years.

I would never use it for temperature data as it only indicates surface temperature and as explained above that is rarely accurate for depth.

Even if reports from random divers are off by 2ºC (4ºF) that is still useful information. Typically you want to know the water temperature beforehand to make decisions such wetsuit vs drysuit, what undergarments, heated vests, etc. Knowing it is going to be 16ºC or 14ºC doesn't change things a lot.

 

[Divin'Papaw]

Sorry, but reports from random divers can easily be off by 4 deg F or more, because of PDC inaccuracies and time constants. Not to mention the vertical profiles of temperature.

Of course, but so what? I take that into account and look at it as a number of temperature ranges. Here in SEFL where I dive almost exclusively, all I need to know is whether it is 85+, 80-84, 76-79, or <=75? That along with the forecasted surface temps & winds tell me all I need to know to prepare for a charter.

This approach gives me as good a measure I’ve found to estimate what conditions I can expect.

 

[tursiops]

Of course, but so what? I take that into account and look at it as a number of temperature ranges. Here in SEFL where I dive almost exclusively, all I need to know is whether it is 85+, 80-84, 76-79, or <=75? That along with the forecasted surface temps & winds tell me all I need to know to prepare for a charter.

This approach gives me as good a measure I’ve found to estimate what conditions I can expect.

People are not always as fortunate as you.

 

[Divin'Papaw]

People are not always as fortunate as you.

While that is true, the OP is. This is the exact area he dives. He is a regular poster in the FL forum. That is why I’ve been so focused on this area, as have others, in my response.

 

[SaltyFrog]

I use Windy, Windy as forecasted
Pretty accurate

 

[yitidih737]

forecastnow.info