“Weather Windows” and Coastal Cruising

Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
I believe that experienced coastal cruisers know how to recognize and exploit weather windows for cruising. However, I expect decisions differ depending on numerous variables. For example, as single handing, double handing, or full crew for overnight watches, etc.

I’m curious. What is the widest forecast interval in your zone that you trust for departure to make destination within a “weather window?” How much of your decision factors on point of sail, predicted sea state, wind velocity, or “emergency” refuge harbors or anchorages along your route? How long do you (and your crew) wait (i.e., standby) for a weather window b/f totally giving up on a planned cruise? Do you even really care much about windows? That is, you go when you “need” to go, and just “beef up”as necessary to make your destination when you wish to be there, etc.

For example, coming to Port San Luis this summer from Long Beach, I and my one-other-person crew waited two weeks to make a normally (i.e., nearly always) upwind passage (frequent SCA’s against in summer) of 185 n.mi. in virtually windless conditions w/low seas nearly all of the way; stopping each of two nights for the three days of transit. Of course, we were therefore motoring nearly all of the way. The window interval forecast we trusted was 5 days. That is, we trusted 5 days of window forecast to make three days of transit plus one day of “staging.” However, good conditions extended beyond the 5 days.
 
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Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
KG. Good query. I suspect it is a bit about the person. One are they “contentiously competent” about getting and understanding weather forecasts. Or are they “looks good for tomorrow, lets go” folk.

I tend to be a planner and look for several weeks before a planned trip using multiple resources and routings in order to optimize my conditions on the water. If I want to just visit, then lack of wind is not a factor I can power across the water. If I am focused on a sail, then I’ll cancel a trip if the weather looks to be calm for a couple of days.

Due to the routing options we have up here, weather and route planning can mean the difference between an enjoyable adventure and an uncomfortable trip or another night in port depending on what side of the island you are on.

As we approach the month of Faugust it also is an issue of seeing the beautiful surrounding or running into a rock/shallows/crabpots/boat.
 
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Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Well, most know that the 3-day is usually very reliable. And they lose reliability as the period gets longer. So it really depends on what you are doing, and for how long. Are you looking for a solid week of great weather, or a window to make a passage? Often most critical; do you have back-end time constraints that limit options once started? All these factor. No simple answer.
 
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Jan 11, 2014
11,321
Sabre 362 113 Fair Haven, NY
Weather windows are also area dependent. Some areas of the country have more stable weather patterns than others.

Our long cruises are about 50 nm across the lake. The best time for going north is right after a cold front, expect the winds are typically dying N breezes, so the wind is on the nose. It seems we always have to head back just before another front passes and we headed S into a building Southerly breeze. :(
 
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Jan 7, 2011
4,726
Oday 322 East Chicago, IN
Your weather forecasters must be way smarter than the ones I watch in TV. While the weather girl is cute, she can’t accurately predict much more than a few hours into the future.

https://images.app.goo.gl/Wtw131gzXqoecEzu6

My wife is the “weather planner”...always watching the forecast and telling what is going to happen.

I will almost always head out and see what happens. Sure, I know that there is a chance of a thunderstorm...it is summer in Chicago...there is always a chance of a thunderstorm.

Mind you, I am out day sailing and can pretty quickly duck into cover.

I will be going out for a few days on the lake in September, and I do watch for a southern wind since I hope to anchor out off the southern beach.

Greg
 
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Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
I admit, this is kinda a squishy topic with a lot of variables. Let’s just say you want a week or ten-day cruise in July at a turn-around destination of, say, 70 to 100 n.mi. distant. You identify, say, three potential departure times—all weather dependent of course. You skip the first date due to gale force winds forecast for your second and third days day out. The second date looks better from the five-day-out perspective; moderate wind and seas (10 to 15 kt; 3 to 4 ft) for the first couple of days, but that are against you. That is you either beat or motor for the VMG. The longer forecast, 7-9 days ahead shows a following calm, then potential SCA for the time near your return. Gusts to 25 kt; 7-ft seas at 8 or 9 seconds, mostly in the afternoons, but favorable to your direction home. Would that be a “go”, or hold out for better conditions near your third departure date? What would make a difference, I wonder?
 
Nov 8, 2010
11,386
Beneteau First 36.7 & 260 Minneapolis MN & Bayfield WI
Your weather forecasters must be way smarter than the ones I watch in TV. While the weather girl is cute, she can’t accurately predict much more than a few hours into the future.

https://images.app.goo.gl/Wtw131gzXqoecEzu6

My wife is the “weather planner”...always watching the forecast and telling what is going to happen.

I will almost always head out and see what happens. Sure, I know that there is a chance of a thunderstorm...it is summer in Chicago...there is always a chance of a thunderstorm.

Mind you, I am out day sailing and can pretty quickly duck into cover.

I will be going out for a few days on the lake in September, and I do watch for a southern wind since I hope to anchor out off the southern beach.

Greg
TV???

I never ever get my sailing weather from TV.

Use one of the noaa-based marine sites, back by the local NOAA discussion. Tons of good info there for the weather geek.

https://forecast.weather.gov/produc...LH&product=AFD&format=CI&version=1&glossary=1
 
Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
KG. In your scenario and assuming we are talking West Coast. I would look at the forecast weather and further out into the Pacific to examine what is driving that forecast. I would likely go depending if I want to be at the destination during a certain window. Since the weather data is generally well reported in programs like Passage Weather and Windy I can understand my exposure as well identify events that would cause me to seek shelter in one of my ports of possible call along the way or even return early should conditions change. I am not a "OMG we got to get there by the evening of the 10th or life will cease to be relevant" type of sailor. If it is no longer safe I am going to be in port waiting for the next window.
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
I think forecasting in the western North Atlantic is of a more tenuous nature than in the eastern North Pacific. Here, the coastal wind blows mostly from within a narrow interval, west to northwest, in summer. So, the forecast tends to be a matter of degree—how hard and for how long, etc., allowing for local variances. There in the WNA, including the Gulf of Mexico, the forecasts are harder to trust, IMHO, and have more history associated with “disaster.” But I still haven’t learned what keeps folks home, versus what initial forecast conditions (weather window) would be a go on a 7 to 10-day cruise along either coast.
 
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Jun 14, 2010
2,081
Robertson & Caine 2017 Leopard 40 CT
I use PredictWind (primarily GFS model) as a go-to then look at NOAA and Wunderground. I try to avoid thunderstorms and wind-against-current situations. I also try to avoid windward slogs in anything above 10kts true.
I’m not always successful at these things, because we do get out there and it’s a game of odds.
 
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Mar 26, 2011
3,400
Corsair F-24 MK I Deale, MD
Another factor is the expected direction of strong winds. For example, on the East Coast strong winds seldom come from the south. Even 4-7 days out, a least the direction of approaching weather and the probably direction of strong winds can be guessed at. if they are on the nose or make your bail out point into lee shores, that is bad. If the wind will be from behind, that's less of a risk.
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Your best forecast is only about 5 days. Long term stretching it, 10 days.

You can do it all using Windy.com
Real time Example....
The Admiral and I just got tired of waiting on Slow moving Hurricane Barry and decided to head out Sunday Morning to Day Cruise to Panama City, FL. After I saw a break in the weather.
Sunday 14th showing route and distances.
7:14_1.jpeg

We have a good 14 knot steady winds from the South, no tacking, we will average 6 knts/hr.
Anchor off the Island at Point 5.

Monday 15th...
7:15_3.jpeg

Up at dawn , still steady 14 knots, we make it to Pensacola #7 or beyond a bit . Clear weather.

Tuesday 16th...
7:16_3.jpeg

Winds are falling off, but steady from South, a bit slower but we make it to Destin early, transient berth and go shopping. Have a great seafood meal. Back to AC'd boat, top of diesel for generator.:snooze::snooze:

Wednesday 17th.
7:17_4.jpeg

Arrive at Panama City and enjoy a few days there.
____
Now the return trip, will be planned last the Forecasts are updated...
___
I changed Windy's ECMWF and added Rain and Thunder Storms as the display.
The Wind speed were the Forecast on those pin/flags in this real example

Tahhh Dahhhh...;)
Jim...
 
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Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
Yes it is. Also on a PC 27” screen with a fast internet connection. You can see the weather of the world. Compare multiple weather models. It is a cool program.
 
Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Yes it is. Also on a PC 27” screen with a fast internet connection.
This is what I use at home. I especially like the long-range forecast ability generally. But as we know, weather is not something that “stands still.” A forecast is a snapshot at time t. At time t +1, you get another snapshot, etc., which is the updated forecast. I consult other information sources as well. For example, I’ve lately been studying the plots of wave energy versus wave frequency/period (i.e. spectral density) that are posted (link) with NOAA’s buoy data. Of course, I’m looking mostly at Station #46011, 21 n.mi. NW of Pt. Arguello, CA in anticipation of my return to the Bight waters this week.

Right now the plot shows very strong dominance of waves with periods of between 7 & 8 secs; average wave height 5.9 ft. Far more of the wave energy resides in those steep waves than in the swell component at 20-sec period. NOT wonderful. By comparison at Station #40625, Santa Monica Basin, total wave energy is much less and the swell component strongly dominates the spectrum. Is wonderful unless, perhaps, you’re trying to anchor the night in a cove wide open to the swell direction.
 
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Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Your best forecast is only about 5 days. Long term stretching it, 10 days.

You can do it all using Windy.com
Real time Example....
The Admiral and I just got tired of waiting on Slow moving Hurricane Barry and decided to head out Sunday Morning to Day Cruise to Panama City, FL. After I saw a break in the weather.
Sunday 14th showing route and distances.
View attachment 167167
We have a good 14 knot steady winds from the South, no tacking, we will average 6 knts/hr.
Anchor off the Island at Point 5.

Monday 15th...
View attachment 167168
Up at dawn , still steady 14 knots, we make it to Pensacola #7 or beyond a bit . Clear weather.

Tuesday 16th...
View attachment 167169
Winds are falling off, but steady from South, a bit slower but we make it to Destin early, transient berth and go shopping. Have a great seafood meal. Back to AC'd boat, top of diesel for generator.:snooze::snooze:

Wednesday 17th.
View attachment 167170
Arrive at Panama City and enjoy a few days there.
____
Now the return trip, will be planned last the Forecasts are updated...
___
I changed Windy's ECMWF and added Rain and Thunder Storms as the display.
The Wind speed were the Forecast on those pin/flags in this real example

Tahhh Dahhhh...;)
Jim...
Great response and example, Jim!
KG
 
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Jul 27, 2011
4,988
Bavaria 38E Alamitos Bay
Weather windows are also area dependent. Some areas of the country have more stable weather patterns than others.

Our long cruises are about 50 nm across the lake. The best time for going north is right after a cold front, expect the winds are typically dying N breezes, so the wind is on the nose. It seems we always have to head back just before another front passes and we headed S into a building Southerly breeze. :(
Similar as to when I sailed in FL during the primary season, which is late fall, winter, early spring. Generally, the west coast of FL tends SE-NW. The long axis of Tampa Bay is NE-SW. The prevailing wind is SE. About half the time (but it seemed more) we cruised south-southeast (outbound) into SE wind; then north-northeast (inbound) into NE wind:doh:. There, however, weather-window considerations are mitigated somewhat b/c of the ICW. You can be out in some pretty snotty weather if inside the barrier islands. Mostly what keeps folks home in FL from at least weekend cruises (short distances) is temps. Lows anywhere in the 50’s F and most folks would not anchor out. No one had fuel heaters. However, they might go to a marina. One of our members fully enclosed the cockpit of his Cat 320 w/Lexan windshield, flex side & back panels—the whole enchilada. Sit in that cockpit in 12 kt with a wind chill outside of 50 deg, but with the sun out, and you’re as warm as fresh toast! Very nice. But still, no heat below at night.
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
with NOAA’s buoy data
There are many data buoys along my example route. Some have daytime cameras for visible sea state, wave action etc.
https://www.ndbc.noaa.gov
Since we are "example" Sailing today, east bound we are now passing Biloxi, Ms.
plot_wind_pres.php-3.png
We see buoy #PTBM6 about 2 hours in front of us. The winds are a bit higher off shore at 16 knots steady so we are doing a bit of wave "quartering" and slight tacking for comfort. Barometric pressure is on the rise so clear weather continues. But where will we anchor at dusk. Looking at station pictures, we decide to anchor on the North side of Dauphin Island, AL. out of Southern wave action.
dpia1_000.jpg
The Admiral asks about the Sunset expected for relaxing evening with adult beverages.
So we have full cloud cover now and a bit of annoying light rain and it will be about the same tonight.
https://graphical.weather.gov/sectors/southmissvlyMarineDay.php?element=WindSpd
Sorry but skies will not clear tonight. Dang, all below deck for and nice evening.
Good News , Destin FL will be clear skies and relatively Cool days tomorrow.:):)

Jim...

PS: We should use the Weather and Forecasting Forum , that Phil made us for this type of shared discussions.

PSS: Dang, we will be slowing to 5.5 knots tomorrow as I find surface currents will be Westward tomorrow.
https://hfradar.ndbc.noaa.gov/index.php?s=DPIA1
 
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Oct 22, 2014
20,992
CAL 35 Cruiser #21 moored EVERETT WA
During our cruise in Belize I used Windy to give us weather repots for planing our daily sails and nightly anchorage. It served our needs. We received a morning weather brief from the base station but it was more a general pattern and only once a day. If a squall appeared or a fast moving front, then the morning brief would be useless.
Knowing the surrounding land and weather patterns is very helpful when transiting a new location. We read the guide books. They briefed on the basic weather patterns for different seasons. This helped identify areas to watch. For us it was the weather in the Gulf of Honduras, the weather crossing Guatemala from the Pacific, the conditions out in the Caribbean affecting the trade winds and the affect of winds and weather fronts as the reach land and turned. All of this was new to us. It never hurts to ask locals what they think.