Author Topic: 120 rule?  (Read 833 times)

Miss Adventure

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120 rule?
« on: March 19, 2017, 07:31:31 PM »
What is your opinion about the 120 rule of thumb (you can ditch the wet suit when the air and water temp combined equals 120 or greater). I MUCH prefer warm (ok, HOT) water, but as far as just safety goes (not necessarily comfort), do you think 120 is enough? I found this article recently about the 120 rule:
I had just been thinking about this because of the warm weather we had a couple of weeks ago. It was about 70 degrees outside which got me itching to get on the water, but the water temp is still around 55. Two days later it was 25 degrees colder outside and the water was still 55. BTW, I'm not talking about surf SUP, just sound-side lazy relaxing SUP. Even though 70+55=125 I still wouldn't have risked it without a wet suit. Would you? 


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Re: 120 rule?
« Reply #1 on: March 19, 2017, 07:45:13 PM »
Depends on where you are and what you're doing.  If you have a chance of being stuck for a few hours or more, then no. If you're going to be sitting around or standing around much, then no.  But I trunk it in the gorge often when it's 70 + 40. I have a built-in Orca suit to begin with, and downwinding is pretty active.

And of course, if it's Celsius, then no.
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Re: 120 rule?
« Reply #2 on: March 19, 2017, 07:53:53 PM »
Nah, if the air and water are both 60 I'll still be in a drysuit.

On the other hand, for SUP surf, the 100 rule works for me.  If the combined temp exceeds 100, it's time to step down to a full 3/2 suit.

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Re: 120 rule?
« Reply #3 on: March 19, 2017, 08:49:33 PM »
Funny how this differs as to the area. When the combined temperature is 100º, I'm usually in my thinner wetsuit  2.5MM with a 1.5 MM jacket. Only when it gets lower do I go for the blubber suit. When the water gets about 55º and the air is warm, I go without anything. I know I can take a fall in mid 50s water with warm air. I've done it lots of times, and in Cape Cod that's kind of normal.

You have to know your conditions too. If it's calm you might not fall in at all. You also have to know your board. I might dress differently for a tippy raceboard in cold weather than a nice wide cruiser.
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Re: 120 rule?
« Reply #4 on: March 19, 2017, 09:29:52 PM »
Today, 55 water temp, 55 air temp with just a little sun barely coming through the clouds.

For surfing, I wore wetsuit shorts (various thickness 3mm, 6mm, 8mm) and a thin 1mm vest.

Plenty warm surfing although my feet were a bit cold initially.
Fell in after the forth wave and then again a couple of times later.
Out for about an hour and a half.

Once I warmed up, I was plenty warm.
Of course, I was also always fairly close to shore without any danger of being stuck out there.

After the fact, I guess I could have just trunked it, but I wouldn't have been as comfortable.

I usually trunk it surfing if it is 60 or higher air temp and sunny.  Water is usually 55 so the magic number
in our area is about 115 for surfing ---- I'd say higher for lazy relaxing supping around, since  you wouldn't likely
be heating your body up as much.

Oh yeah, wind was 4mph or less. 
« Last Edit: March 19, 2017, 09:38:08 PM by Subber »
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Re: 120 rule?
« Reply #5 on: March 19, 2017, 11:03:25 PM »
Dress for the swim. 

In benign conditions I don't always do it and you mentioned no surf, but if there is more than a slim chance of me swimming any distance I dress for that.  Couple weeks ago I had to swim a few hundred yards after my leash broke in 50-something water with just a 2mm top on.  Didn't feel any real danger of hypothermia but I also didn't see my nuts for about 3 days after ;)


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Re: 120 rule?
« Reply #6 on: March 20, 2017, 05:27:06 AM »
Hi Miss Adventure

If the water is above 50 F, I always dress for air temp.... even when surfing.
If the air is 65, light wind and sunny, I can easily handle falling in without a wetsuit, since you are in less than 10 seconds.
Jump back on the board and sun dry in 65* air.

If I wear a wetsuit at those temps, I sweat to death and jump in just to cool off.

If it's early in the season and the water is still under 50 but the air is above 70... I'll wear a 1.5 mil long sleeve vest.
The reality is you are in the air all the time. Even if surfing, you are only in the water momentarily... and a measure of safety for a longer swim.

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Re: 120 rule?
« Reply #7 on: March 20, 2017, 06:08:17 AM »
On flatwater, if the air is above 65 I often don't bother with a wetsuit. This time of year in NH it can be 75+ degrees and the water still be in the 30's or 40's. Way too hot for a wetsuit but if you fall in it's no big deal. You'll warm up in a few minutes once you get back on the board.

When the air is warm and water is cold, you just have to be absolutely sure that you're not going to become separated from your board or there is a good chance you might die. Always consider what would happen if your leash broke. Would you be able to get back to the board in time?

If your leash is more than three years old, throw it away and get a new one. Never leave your leash in the sun. Never drag your leash on the ground.

« Last Edit: March 20, 2017, 06:13:30 AM by Badger »
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Re: 120 rule?
« Reply #8 on: March 20, 2017, 08:04:44 AM »
Since I don't wear a wet/dry suit and with me being  a light weight of 150 pounds, I have my own "Rule of 132" which means the air temperature is 66 degrees F and the water temperature is 66 degrees F.

As an example, today's air temperature is forecast for 85 degrees F and the water temperature at Lake Conroe is 65 degrees F. If my right rotator cuff wouldn't be torn, I would be paddling on Conroe for a few hours instead of me posting messages right now on the Zone.
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Re: 120 rule?
« Reply #9 on: March 20, 2017, 09:13:33 AM »
Sorry Miss Adventure,

But I just don’t agree with these type of “rules”. You dress for the water temperature, full stop. Hypothermia is no joke and can kill very quickly. I suppose if there is absolutely zero chance you will fall off your board, or that if you do fall off you know for certain that you can get back on quickly, then you could have other considerations. Just remember though that if you’re in cold water for any length of time and you’re not dressed for it, getting back on your board will become much more difficult than it otherwise would be.

And as Badger says, if there is any chance you will become separated from your board, and you’re not dressed for the colder water, then you are in very serious trouble.


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Re: 120 rule?
« Reply #10 on: March 20, 2017, 09:37:14 AM »
I have the sweaty pig rule.  If I'm a sweaty pig during the walk to the water, The wet suit stays on shore.  ;)
Really, it's all about comfort.  Thursday I was in a 3-2 full suit, and regretted it after about 15 minutes.  Friday I wore my go-to winter 2 mil long johns, and was a happy camper all day long. Water about 59, air about 65 to 70 at the start.  Sure there were guys out without suits, but I don't base what I find comfortable on what others are doing.


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Re: 120 rule?
« Reply #11 on: March 20, 2017, 10:35:01 AM »
Kinda play it by ear.  But was out yesterday.  2 DW buddies were in shorts - a lady friend in tights - and myself in shorts.  Temps were air 45 and water 41.  We as a group rarely fall in the ocean.  The winter sun was out.

I was out a bit earlier and paddled around 4 miles solo in about 12 kts of breeze.  Then the wind dropped to 3 kts.  The chance of falling in that was extremely low.

We maybe were all a tad cray cray.  But have been doing this for years with nary an incident.  When air drops to sub 40 then on comes the drysuit.  But anything over 40 in the drysuit becomes very warm in just a few minutes.

Do not do this unless you know your abilities and know how to self rescue.  It is risky and not recommended.  Yesterday we were 2 miles out from shore.  Which is our norm.  If your balance is ever questionable -> wear a wetsuit or drysuit.  Or do not go out.  Much better to be safe and sweaty vs wet and frozen.  ;)
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Re: 120 rule?
« Reply #12 on: March 20, 2017, 10:52:53 AM »
Never heard of this rule and don't really follow it.  Like has been said, I have something that works for me and my area.  If it's above 40F at dawn when I arrive at the beach for an open ocean paddle, it's trunks and a rashguard--given where I live that means I rarely wear anything else.  Might be chilly when I get started but that lasts about 3min.  Water temp at it's coldest is mid50s and I probably only fall in 2-3x per year.  Add to that, I never go without a leash.

Might get a little warmer when I'm surfing but even then, I probably wear my full-suit less than 5 times a year.
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Re: 120 rule?
« Reply #13 on: March 20, 2017, 02:02:42 PM »
Dress for the water or else know the risk you are taking, and bear in mind that your misjudgment might put someone else at risk. Use common sense, and assess the risk for yourself rather than follow some adage. It's your life. Too hot is unpleasant, but it's rarely as dangerous as too cold.


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Re: 120 rule?
« Reply #14 on: March 22, 2017, 01:13:36 PM »
What I wear for running or walking soaking wet in similar atmospheric conditions is my guide. I pack an extra layer just in case. I cruise and do fitness paddles - maybe similar to you. 

No talk of wind chill yet - does that factor into the wind temp part of the formula (admission - I didn't follow the link)


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