• Sailing is all about the Weather.

    Big into the exploration of Atlantic Hurricanes since Katrina came uninvited into his world, James (Jim) Gurley (JamesG161) has followed every Tropical Storm birthed in Atlantic, Gulf and Caribbean waters since. Being a boater, he knows that we often need more time to prepare than we get from the TV weather folk. Jim relies on the science of storm development to share early warning info with friends and fellow boaters.

    Early in 2018, Jim and John Shepard, (JSSailem) started to chat about the weather data available. John asked Jim to help forecast Pacific NW storms, and this morphed into discussions on weather forecasting.

    For John, sailing in the PNW is sometimes hit and miss. One day is ugly, then a string of beautiful days but no wind, followed by a series of blue-sky days and 12 knot breezes. Being ready for those great sailing days means you need to look to the Pacific Ocean and what is brewing. John has been into Pacific NW Weather since the 1970’s when his first PNW November storm hit bringing more than 40 days and 40 nights of continual rain.

    Together we want to share information, new APPs, safety, and thoughts about letting the weather help you. Identify some of the resources for sailors and help prepare you for your next sailboat outing.

    It is far better to go out on the water knowing what to expect in weather terms, than to be out on the water and see dark ominous clouds suddenly appear, unprepared.

Wind and Seas for Sailors.

Oct 22, 2014
21,088
CAL 35 Cruiser #21 moored EVERETT WA
We have talked about wind and weather mostly about managing our exposure and avoiding dangerous sailing conditions.

I got to thinking, for the experienced among us, we talk about reefing when the wind picks up. That is a nebulous statement. How do we know that the “Wind” has picked up? Not everyone has electronic gear to tell us “this breeze is 10 knots... let some sail out.“ Or “ it is getting 18-20 knots. Perhaps the heeling is getting too much in the gusts - better ad a reef and reduce the jib”

Without all these electronic aides how did sailors survive. How did they know it might be time to alter the sail plan by shrinking “Reefing” the sails.

We have Sir Francis Beaufort to thank for the invention of the Beaufort Scale. Being an Irish hydrographer, Beaufort developed a scale based upon wind and sea observations while serving in the Royal Navy. The scale gives sailors a common tool to base their wind and sea observations when sharing weather information.

Beaufort Wind Scale
Developed in 1805 by Sir Francis Beaufort, U.K. Royal Navy

Force​
Wind
(Knots)​
WMO
Classification​
Appearance of Wind Effects​
On the WaterOn Land
0
Less than 1CalmSea surface smooth and mirror-likeCalm, smoke rises vertically
1
1-3Light AirScaly ripples, no foam crestsSmoke drift indicates wind direction, still wind vanes
2
4-6Light BreezeSmall wavelets, crests glassy, no breakingWind felt on face, leaves rustle, vanes begin to move
3
7-10Gentle BreezeLarge wavelets, crests begin to break, scattered whitecapsLeaves and small twigs constantly moving, light flags extended
4
11-16Moderate BreezeSmall waves 1-4 ft. becoming longer, numerous whitecapsDust, leaves, and loose paper lifted, small tree branches move
5
17-21Fresh BreezeModerate waves 4-8 ft taking longer form, many whitecaps, some spraySmall trees in leaf begin to sway
6
22-27Strong BreezeLarger waves 8-13 ft, whitecaps common, more sprayLarger tree branches moving, whistling in wires
7
28-33Near GaleSea heaps up, waves 13-19 ft, white foam streaks off breakersWhole trees moving, resistance felt walking against wind
8
34-40GaleModerately high (18-25 ft) waves of greater length, edges of crests begin to break into spindrift, foam blown in streaksTwigs breaking off trees, generally impedes progress
9
41-47Strong GaleHigh waves (23-32 ft), sea begins to roll, dense streaks of foam, spray may reduce visibilitySlight structural damage occurs, slate blows off roofs
10
48-55StormVery high waves (29-41 ft) with overhanging crests, sea white with densely blown foam, heavy rolling, lowered visibilitySeldom experienced on land, trees broken or uprooted, "considerable structural damage"
11
56-63Violent StormExceptionally high (37-52 ft) waves, foam patches cover sea, visibility more reduced
12
64+HurricaneAir filled with foam, waves over 45 ft, sea completely white with driving spray, visibility greatly reduced

Sailing in a variety of wind and sea conditions, and observing/recording the observations, you can develop a reliable tool to aide your sailing. You can check your observations with the weather reports to help improve your ability as a weather observer.

How do you do this? Well get out on the water and raise your sails. It looks like a beautiful day. A you power out of the slip you gaze at the water and see wavelets covering the bay. You feel the breeze on your cheek you raise your sails and your boat responds, moving at an enjoyable speed. Maybe a little heel and some of the wavelets (say 20%) have white wave caps.

Checking the Beaufort scale you determine maybe a 2 or a 3 force Light /Gentle breeze. The Beaufort scale is not an exact nor an objective scale; it was based on visual and subjective observation of the sea. So you look up the weather condition on your cell phone weather app. It reports the wind at 5 to 8 knots.

This is a time for a sail and a :beer:.

So your next day you head for the boat, you see that the flags in the marina are whipping straight out. You get excited about the possibility sailing. Looking out at the water, beyond the break water, you see waves.. They break on the break water. 75% of the waves in the bay have "White tops" and some are breaking with spray. What would Beaufort say abut this? Well maybe this is a Moderate or even a Fresh Breeze. It is very tempting. So I am going to follow the advise on SBO and rig the boat with reefs. I'll start with a single reef on the main and because I have roller reefing when I open the fore sail I'll start with maybe only 50% of the sail.

We go out and have a great time. There were a few gusts and the boat would heel. A couple of times you get that scary feeling in your stomach, but your boat settles and your feeling pretty good about your sailing abilities.

Checking our trusty weather app, we see the experts telling us the winds are 14 to 18knots. with gusts to 20. Force 4-5 on the Beaufort scale.

I was watching a Norwegian sailor who videoed his experience sailing in a Force 10 gale. Here is his shared experience.

I hope you soon get the opportunity to test your wind and sea observation skills. :thumbup:
 
May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
reading the surface of the water has always the best gauge for determining the wind speed. being able to read the wind way before it hits you is a must. looking up wind will give you time to adjust before it changes. once it hits the fun little anemometer on the masthead it's too late. reading the water, reading the sky to gauge what is about to hit you is a very important skill for the sailor. and what about at night? oh no! well actually when your eyes adjust to the darkness you can see quite well at night maybe 70% of the time, if you run a blacked out helm/cockpit/deck. yep, all lights should be turned off and or shielded from all on deck at night otherwise your running blind. yep, blind to reading the wind from the beaufort scale.
 
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Jan 19, 2010
1,171
Catalina 34 Casco Bay
reading the surface of the water has always the best gauge for determining the wind speed. being able to read the wind way before it it's you is a must. looking up wind will give you time to adjust before it changes. once it hits the fun little anemometer on the masthead it's to late. reading the water, reading the sky to gauge what is about to hit you is a very important skill for the sailor. and what about at night? oh no! well actually when your eyes adjust to the darkness you can see quite well at night maybe 70% of the time, if you run a blacked out helm/cockpit/deck. yep, all lights should be turned off and or shielded from all on deck at night otherwise your running blind. yep, blind to reading the wind from the beaufort scale.
I've sailed on a lake, and while our boat is technically moored in a river, it is a harbor river. I totally agree with reading the surface of the water. Always looking for the "puff". Sometimes the subtle surface changes get confused.. When you have tide to contend with it makes the game all that more interesting. This is where local knowledge comes into play. Aside from knowing how far you can cut an ATON, it's the realization that the in coming tide at is's mid point is causing that surface disruption along the dredged channel line where the tide rises up over the shoal. Depending on the wind direction, the surface telltale maybe neutralized or exacerbated. Isn't this why we sail? That satisfaction you get from the correct read..
Then there is the returning. Up river ( current), against the falling tide and 15kts on your nose....ahhh the chase is on.
 
Oct 22, 2014
21,088
CAL 35 Cruiser #21 moored EVERETT WA
When I was a boy of 15 and racing in 14ft dinghies we discovered "local knowledge" doing things I would never do with my 35ft boat. But we were a bit crazy and feeling invincible.

Worst remembrance was 16 in a SD Bay Regatta of Lido 14's. We had built a 13 boat length lead from the pack by luck, all out sails, and playing the puffs/gusts. It was eventually gusting 20. Last leg was a reach that exposed us to the ocean breeze over the sand spit that stretches from Coronado to Imperial Beach. I was confident this was our race so we were full sail and hanging off the side trying to keep the boat on the water.
Swoosh... a 25plus gust swept across the fleet. We went over. Got boat righted. Standing in a hull full of water bailing with anything we could grab. Sails up. Trying to pick up speed. Hopping we did not flip again. Sails flapping. Hoping to get near the lee of the large buildings so we could recover.

Story ended with us crossing in second, but then it came out the first boat was DQ. They missed a mark.

Local Knowledge. Learn to read the wind. Be ready to adapt.
 
May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
i am a barometer weather forecaster geek. it too can give you an idea as to what to expect.
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
on the surface thermal excitation gives us many surface winds that we can learn to expect as we sail along. sea breeze on shore along a coastline during the day. an offshore breeze at night along a shore line.
clouds of all shapes and sizes indicate what to expect on the surface. thunderstorms switch from updraft to down draft when the rain starts to fall. outflow/inflow. thunderstorms are big furnaces creating huge heat.
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
winds entering a bay will funnel and increase. winds leaving a bay will fan out and decrease. winds hitting a large land mass will lift off the deck to go up and over. winds coming off a bluff will angle down and slam into the deck offshore.
wind has drag on the surface and will be stronger aloft until around 26 knots when the surface wind gets washed out.
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
keeping a close eye on your barometer is akin to keeping a close eye on your nav chart, it's helping to navigate the atmosphere
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
sailplanes get towed aloft, they then release and glide around and then back to the ground. catching thermals will increase their flying time. they too are wind toys. as these pilots increase their knowledge of the unseen wind they can fly longer and farther. sometimes they can go hundreds and hundreds of miles. well, moving air makes us move and learning where to expect high speed winds going from a to b is rarely talked about. i find few sailors to have good discussion about the nuances of our sailor's wind. the wind is our fuel. it is never constant. predicting the winds on any given day, seeking the most favorable winds so to optimize the sailing, and then sailing our vessels to the well with these winds is a fun game i think.
having this discussion with other sailors is rare. the only book that i have found that talks about the sailors winds in a very comprehensive way are Frank Bethwaite's books. he suggest sharing wind discussions with other sailors as a way to improve our wind predictions. in my sailing travels i ain't found those people yet, and i sail allot.
i just like sailing well.
 
Oct 22, 2014
21,088
CAL 35 Cruiser #21 moored EVERETT WA
in my sailing travels i ain't found those people yet, and i sail allot.
Jon though we can’t share this info over a beverage on your beautiful aeolus-1966 caravelle. We will have to make do with this new fancy fangled typing do hicky. Instead of shouting we can share our ideas with this magic.
Any time day or night.
Won’t replace the joy of face to face but it’s better than a kick in the pants.
:)
 
Jan 19, 2010
1,171
Catalina 34 Casco Bay
We basically sail in an archipelago referred to as the Calendar Islands. While there are not 365 there are over 200. Sailing thru one of the many passes the local knowledge aspect always pays dividends. The windward island shelters the wind from making it back down to the surface before mid-channel. Mid-channel to the next island..Cats-paws on the water.. But there is wind aloft. The sea state might be glass, but the wind machine is indicating 12-15kts at the mast head.. Visiting captains try to stay in the cat's paws..they get set... Staying in the "glass" but with wind aloft makes for a nice run..
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
the united states coast pilot lists 136 calendar islands. but heh, the biggest race on green bay is called the hundred miler and maybe a long time ago it was a 100 miles long, but it's only a 43 mile course. something about the yupper's wanting the race to finish well before the bars close. :)
 
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May 25, 2012
4,335
john alden caravelle 42 sturgeon bay, wis
pulsing air
oscillating air
ribboning air
....... and what about the roll mechanism
 
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