Winter vs. Summer Sails - SailNet Community
LinkBack Thread Tools
post #1 of 6 Old 04-29-2014 Thread Starter
Senior Member
Join Date: Jul 2011
Location: portland oregon
Posts: 106
Thanks: 4
Thanked 2 Times in 2 Posts
Rep Power: 6
Winter vs. Summer Sails

This is likely off topic. But I could find no better place to for it.
I am getting ready to change my sails from the winter sails to the summer sails. The reason is the winter sails are old and slow. Over the years I've noticed that the winter wind and the summer wind are different. Aside from being cold and wet, the winter wind seems to be stronger for the same knots. A 20 knt wind is still 20, but in winter the 20 knts seems to have more punch. I think this effect may have something to do with temperature and the number of molecules being pushed around. Any thoughts?

Quote: The wind and waver are always on the side of the ablest navigator.-Edward Gibbon, "The Decline and Fall of the Roman Empire"
luck66 is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
post #2 of 6 Old 04-29-2014
The most female moderator
Donna_F's Avatar
Join Date: Nov 2005
Location: SE Pennsylvania
Posts: 5,444
Thanks: 128
Thanked 270 Times in 249 Posts
Rep Power: 10
Re: Wind and Sails

Luck, I'm going to move this into its own thread. It is a good discussion starter and I don't want it to get buried.


To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.

To view links or images in signatures your post count must be 10 or greater. You currently have 0 posts.
Catalina 30 TRBS
Rock Hall, MD

If you're helping someone and expecting something in return, you're doing business not kindness.
Donna_F is offline  
Quote Quick Reply Share with Facebook
post #3 of 6 Old 04-29-2014
Ajax_MD's Avatar
Join Date: Nov 2009
Location: Edgewater/Annapolis
Posts: 4,139
Thanks: 7
Thanked 118 Times in 108 Posts
Rep Power: 8
Send a message via Yahoo to Ajax_MD
Re: Winter vs. Summer Sails

Cold air is denser than warm air, so essentially more mass is pressing on your sails so yes, the punch is greater.

It's the equivalent of being hit with a 5 lb. mass at 20 kts vs being hit by a 2 lb. mass at 20 knots.

Automobile engines meter fuel differently during cold weather because the denser air changes the fuel/air ratio, as another example.

1981 Tartan 33 #168
Ajax_MD is offline  
Quote Quick Reply Share with Facebook
post #4 of 6 Old 04-29-2014
Bristol 45.5 - AiniA
Join Date: May 2006
Posts: 4,470
Thanks: 5
Thanked 120 Times in 108 Posts
Rep Power: 11
Re: Winter vs. Summer Sails

I suspect it is like the difference between being hit by a 5 lb mass and and a 5.1 lb mass. I don't remember my details of Boyle's Law if that is the correct on, but the pressures are different, but not that different with the temps we are talking about.

Finishing our major refit. Our trip to Newfoundland is off because it is too late. Hoping to go to the North Channel instead.
killarney_sailor is offline  
Quote Quick Reply Share with Facebook
post #5 of 6 Old 04-29-2014
Senior Member
Minnesail's Avatar
Join Date: Feb 2013
Location: Minneapolis, MN
Posts: 1,819
Thanks: 148
Thanked 68 Times in 67 Posts
Rep Power: 5
Re: Winter vs. Summer Sails

I think the volume of a gas is linear with temperature when measured in degrees Kelvin. The Kelvin to Celsius conversion is 273º (thank you Wikipedia).

So if the temperature went from 273ºK (freezing) to 303ºK (a warm sunny afternoon) we do 273/303 = 0.9, so the air would only be 90% as as dense as it was at freezing.

Humidity might have more to do with it. Humid air is less dense than dry air (even though it doesn't feel that way) and warm summer air is going to be a lot more humid than dry winter air.

Catalina 22
on a starboard tack
Minnesail is offline  
Quote Quick Reply Share with Facebook
post #6 of 6 Old 04-29-2014
Senior Member
Join Date: Feb 2012
Location: New Orleans Louisiana
Posts: 3,160
Thanks: 10
Thanked 126 Times in 120 Posts
Rep Power: 6
Re: Winter vs. Summer Sails

The density of air doesn't change that much with temprature.

Temp.....density (lbs/foot^3) Air - Temperature, Pressure and Density

My guess is that the difference is in your head more than in reality. Any difference here is probably equalled out by the lower absolute humidity of the colder air.

Stumble is offline  
Quote Quick Reply Share with Facebook

Quick Reply

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page

Similar Threads
Thread Thread Starter Forum Replies Last Post
Summer sails now on NewsReader News Feeds 0 08-14-2013 01:30 PM
Reason #39 Why Summer is Better Than Winter bljones General Discussion (sailing related) 2 03-11-2011 09:02 PM
Sail in summer, program in winter avanti2001 Introduce Yourself 0 09-19-2010 05:12 PM
looking to crew winter 2008 or summer 2009 barefootbook Crew Wanted/Available 1 09-20-2008 08:44 PM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

For the best viewing experience please update your browser to Google Chrome