Weather info on Atlantic voyage

[ludo.verhavert]

Hypothetical:
Suppose that our sailing vessel makes a trip from the Canary Islands , eventually passing by the Cabo Verde islands, then crossing the Atlantic to the southern Caribean islands ( Grenada, Saint Lucia, Barbados) , then :
which are the preferable shore stations and their frequencies , for that particular route , that could be contacted for weather information by Marine SSB HF , by HAM SSB transceiver , or eventually by Iridium 9555 satphone ?
Do they figure in a Pilot Book ?
Info and experience sharing would be appreciated.
b.regards
Ludo

[AllanR]

Hi Ludo,

Radio stations need to be registered and licensed Maritime Stations with assigned/paid frequency allocations to appear in the official list of Lights and Signals. HAM stations will not appear.

HF/SSB nets operated by committed HAMs and others do a great job and details can be found elsewhere.

My recommendation for reliable reception of weather information is to add a Pactor controller to your existing HF/SB radio and join SailMail (or WinLink if you are a licensed HAM). You can request/receive the official METAREA forecasts for the area and GRIB weather charts for no additional cost.

The significant advantages of receiving weather by email include:

1. You can collect the information when on-board activity permits. It's easy to miss skeds and broadcasts because you are busy.

2. The information is received accurately, as it was intended. Rather than what you manage to hear and write down on a bumpy yacht when voice reception is not optimal.

3. The Pactor controller and SailMail or WinLink software will automatically deal with any problems of reception by requesting re-sends of missed information without you needing to be involved.

Regards

[Palarran]

IMO, spending one single dollar (euro) towards a system based on SSB is wasting two. It's beyond dinosaur at this point.

I have an Iridium 9555. Unfortunately, it is also somewhat useless as the Iridium Go has passed it. Not because of performance, but based on the data plans you can get. Check out https://www.predictwind.com/iridium-go/ to see the data options. You can get an unlimited data plan (super slow but who cares) for $125 / month instead of a year minimum with the 9555. The price difference pays for the new GO. The Predictwind app is very nice also so this is what we are going to be using.

[Suijin]

If you're leaving from the Canaries at the traditional time, i.e. November/December, you'll probably find a number of other boats making the trip, some completing the last leg/legs of a circumnavigation, some participating in the ARC, etc. There will likely be some SSB nets that the boats have formed and participate in, and they can be extremely helpful in terms of safety and getting more localized real-time weather reporting during the trip. Ask around when you get to the Canaries. You're sure to find some.

I agree that given a choice between sat phone and SSB the sat phone is more useful and certainly easier to master. But anyone who is going deep offshore on a popular route who says SSB is a waste of money doesn't understand what it's value is with respect to what it can do that sat phones can't.

[Palarran]

Originally Posted by Suijin

I agree that given a choice between sat phone and SSB the sat phone is more useful and certainly easier to master. But anyone who is going deep offshore on a popular route who says SSB is a waste of money doesn't understand what it's value is with respect to what it can do that sat phones can't.

Would you mind listing those advantages? I can't think of one that wouldn't be instantly eclipsed by a sat phone feature.

Look, I know there are a thousand threads here arguing about the advantages of SSB, but for someone to invest money towards it instead of an Iridium GO simply doesn't make any sense.

[ludo.verhavert]

Thanks to all of you for the good advice !
I definitely will look into the Iridium-go option , and also contact Sailmail.
The advantages of e-mail , over live broadcast in a rough sea acompanied by some radio noise , are obvious . Thks for pointing this out.
I am a radio HAM , so I enjoy contacts with fellow HAM's even at sea.
But I fear that my ICOM7000 is too sensitive to battery voltage drops when transmitting , and not really fit for the agressive marine environment.
I may try to find myself some second hand marine transceiver and Pactor modem ( of which there seem to be quite a few models , hence which one ?)

Thks for the info and good winds to all of you .
Ludo

[lsoltero]

Originally Posted by Palarran

IMO, spending one single dollar (euro) towards a system based on SSB is wasting two. It's beyond dinosaur at this point.

I have an Iridium 9555. Unfortunately, it is also somewhat useless as the Iridium Go has passed it. Not because of performance, but based on the data plans you can get. Check out https://www.predictwind.com/iridium-go/ to see the data options. You can get an unlimited data plan (super slow but who cares) for $125 / month instead of a year minimum with the 9555. The price difference pays for the new GO. The Predictwind app is very nice also so this is what we are going to be using.

The pricing for the Iridum GO! plans is hard to beat. As a comparison a 75 minute prepaid card for the 9555 valid for one month is $149. In comparison one month of unlimited data for the GO + 150 minutes of voice is $124. So... its really a no brainer.
Iridium Prepaid Airtime: 75 Minutes, 1 Month Validity
Iridium GO! Postpaid: GO! Unlimited

A few recommendations though..
1. You should really consider an external marine antenna kit for the GO!. The built in helical antenna does not work very well especially when the unit is below deck.
https://www.iridium.com/products/det...stallation-kit

2. Secondly... you probably want email as well as weather. Note that an XGate subscription includes access to predictwind as part of the package. So you can kill two birds with one stone.
PredictWind Marine Weather and Wind Forecasting Software | GMN

XGate is supplied by a number of different branded solutions including SpeedMail (Network Innovations), SatPhone.Me (Sat Phone Store), SPS XGate (Satellite Phone Store), Sattrans Mail (Sattrans usa), Globalstar Mail, MVS Mail, OnSatMail Plus (AST), OptiAccess (IEC), and others all of which also include a PredictWind subscription and many which don't include a subscription fee if you purchase airtime through them.

3. Note that the IMW app from iridium https://www.iridium.com/iridiummailampwebregistration
is free and provides email but does not include predictwind. So if you choose to use this free email service you will need to purchase the standard version of predictwind. Also note that these apps only work on mobile devices. If you need/want email/weather on your PC or Mac then you should get XGate or one of its derivatives.

4. Finally note that the data speeds on the Iridium GO! are very slow. total number of raw bytes transferred in one minute is about 15KBytes. So... even an unlimited data plan its not practical to browse the internet. CNN.Com is over 1MB in size which would take over an hour (even with compression). There is no way to restart a web download if you have a satellite drop (which happens fairly frequently with iridium ) making it doubly hard to access the web.

So plan to use specialized apps optimizer for satellite use to get the most out of your Iridium GO!

Take care.

--luis

[El Pinguino]

Originally Posted by ludo.verhavert

Thanks to all of you for the good advice !
I definitely will look into the Iridium-go option , and also contact Sailmail.
The advantages of e-mail , over live broadcast in a rough sea acompanied by some radio noise , are obvious . Thks for pointing this out.
I am a radio HAM , so I enjoy contacts with fellow HAM's even at sea.
But I fear that my ICOM7000 is too sensitive to battery voltage drops when transmitting , and not really fit for the agressive marine environment.
I may try to find myself some second hand marine transceiver and Pactor modem ( of which there seem to be quite a few models , hence which one ?)

Thks for the info and good winds to all of you .
Ludo

A second hand IC-M710 would be your best option for a radio.

Re the 7000.... I have had a 7600Mk2-G on board for the last 8 years or so with no problems... as well as a 710. Prior to that I had an IC-735 .. no probs with it either... I think the 'ham radios can't stand marine conditions' is a bit of a maritime myth....

Pactor? a IIex would do the job... its what I have... but if I was starting from scratch I would buy a IIusb.

[conachair]

Originally Posted by ludo.verhavert

Thanks to all of you for the good advice !
I definitely will look into the Iridium-go option , and also contact Sailmail.
The advantages of e-mail , over live broadcast in a rough sea acompanied by some radio noise , are obvious . Thks for pointing this out.
I am a radio HAM , so I enjoy contacts with fellow HAM's even at sea.
But I fear that my ICOM7000 is too sensitive to battery voltage drops when transmitting , and not really fit for the agressive marine environment.
I may try to find myself some second hand marine transceiver and Pactor modem ( of which there seem to be quite a few models , hence which one ?)

Thks for the info and good winds to all of you .
Ludo

Regarding the ic7000 - i use that onboard with a signalink usb soundcard, though I haven't been too far but so far it's been solid. Winlink worked fine across biscay for gribs, even in a marina in the middle of London I manged to log a winlink position. The radio seems perfectly fine so far, not too bothered when the voltage goes down but offshore i've ran the engine sometimes when using it to log on to winlink.

Also, if the choice had to be made I would go for weatherfax over gribs for an offshore passage, the big picture helps. But both is best.

[El Pinguino]

Originally Posted by Palarran

Would you mind listing those advantages? I can't think of one that wouldn't be instantly eclipsed by a sat phone feature.

Look, I know there are a thousand threads here arguing about the advantages of SSB, but for someone to invest money towards it instead of an Iridium GO simply doesn't make any sense.

OK... I'll start.... involving yourself with any of a number of maritime nets... both on Marine and Ham frequencies. Thinking of the South Pacific here... Isabella's, Comedy, Tony's, Patagonian.. all alive and well.

Don't see how a 'one on one' sat phone call can replace that.... and its free.....

[AiniA]

Another take on this, will you need weather info/long range communications capability after this voyage? If not, you may want to save the money that SSB or sat phone will cost you. The conditions of the voyage described will be relatively constant, some years a bit more wind and some years a bit less. Rarely will you get other than normal trade directions. Also, lets assume that you are half way across the Atlantic and find out that winds will be 30 knots rather than the more normal 15 to 20, what are you going to do differently based on getting a forecast rather than reacting to the signs you have onboard - sky conditions, barometer, sea state?

Could it be that I am becoming a curmudgeon?

[Paul L]

Originally Posted by AiniA

Another take on this, will you need weather info/long range communications capability after this voyage? If not, you may want to save the money that SSB or sat phone will cost you. The conditions of the voyage described will be relatively constant, some years a bit more wind and some years a bit less. Rarely will you get other than normal trade directions. Also, lets assume that you are half way across the Atlantic and find out that winds will be 30 knots rather than the more normal 15 to 20, what are you going to do differently based on getting a forecast rather than reacting to the signs you have onboard - sky conditions, barometer, sea state?

Could it be that I am becoming a curmudgeon?

In a world of weather global weirdness I can't see not having access to weather updates during a passage. Sure it's likely to be a downwind, tradewinds passage --- except the year when you get an out of season hurricane. We've already witnessed a S Atlantic hurricane where they just shouldn't be.

[Suijin]

Originally Posted by Palarran

Would you mind listing those advantages? I can't think of one that wouldn't be instantly eclipsed by a sat phone feature.

Look, I know there are a thousand threads here arguing about the advantages of SSB, but for someone to invest money towards it instead of an Iridium GO simply doesn't make any sense.

Sat phone is one to one. SSB is one to many. I've been on many offshore voyages where the discussions/information from the daily net conversations have proven extremely valuable. Also, many professional weather routers broadcast hold conversations via SSB.

I didn't say "instead of". If choosing only one or the other, I'd go with sat phone, as I said, but if you have an SSB already installed, or the cake to buy and install one, they can be very useful.

[ka4wja]

Ludo,
I'm a week late getting to your questions, but I do have some good (and detailed) info for you...and some nice, easy-to-understand videos to watch and actually see how all of this works in the real-world, on a real offshore cruising boat, that actually uses all of this....

(and, I apologize if some of my American/English idioms, etc. confuse you.


1) First, and foremost, is the fact that many vessels make this crossing without any weather info at all, other than looking at the clouds, sea state, and barometer!!
It's been done like this for 100's of years, and while I'm not advocating it, it is still done this way by some!!

And, the simple fact is that the old adage of "head south until the butter melts, and then head west" is actually quite accurate, and allows you to "find the wind" needed for a safe passage....

This passage from Canaries-to-Caribbean is a downwind milk-run, and as long as you make passage at the right time of year and/or avoid tropical weather (Tropical Storms / Hurricanes), you're not likely to find much wind above 20 - 25 kts. apparent, and many times you'll be looking for wind as you head south and/or if leaving too early...


2) And, as you pointedly ask, yes the pilot charts (which are available on-line for free download) will give you some historical data to work with....and it is surprisingly good!!
(I myself invested in some "updated" pilot charts, from Jimmy Cornell, and while I found some slight variations in historical wind speeds in a couple months, along some routes, the differences were minor and certainly that any prudent sailor wouldn't already be prepared for....so, while some will say "buy the newest", it's really unnecessary...)



3) And, while much of the taxpayer-supported, government disseminated offshore and hi-seas weather info and forecasts are meant of large ships (making quick passages), you can quite easily use these systems such as:
NAVTEX (for short-term coastal and near-offshore waters forecasts)..
SafetyNet (for large-scale, generalized hi-seas forecasts)...
WeFax...most importantly WeFax charts (for detailed forecasts)....
(as well as some HF-SSB Voice Weather broadcasts)

You can receive all of these via your Marine HF-SSB radio....for free....
NO expensive modem is required at all, and no subscription, nor fee is necessary....

{Note that NAVTEX in English-language text, is always on 518khz, on your
HF SSB Radio....with some countries using 490khz for their native language text broadcasts...see below for details of what frequencies to use for other services...}


Please note that much of the generalities of all of this was well covered here...have a look!
Offshore / Hi-Seas Weather data / forecasts



4) As for "preferable shore stations", that's pretty easy...
GYA, NMF, DDK, and NMG, as well as NMN, WLO, and DWD, as well as the MMSN, etc...

But, that doesn't really tell you much, does it??

Originally Posted by ludo.verhavert

Hypothetical:
Suppose that our sailing vessel makes a trip from the Canary Islands , eventually passing by the Cabo Verde islands, then crossing the Atlantic to the southern Caribean islands ( Grenada, Saint Lucia, Barbados) , then :
which are the preferable shore stations and their frequencies , for that particular route , that could be contacted for weather information by Marine SSB HF , by HAM SSB transceiver , or eventually by Iridium 9555 satphone ?
Do they figure in a Pilot Book ?
Info and experience sharing would be appreciated.
b.regards
Ludo

5) How about, what is the preferable way of getting decent weather info, on this Atlantic crossing???
Ah, now we have the long answer:

a) The "Gold Standard" of offshore / hi-seas marine weather info and forecasts are those done by the US National Weather Service (and UK Met Office, Aus Bureau of Met, NZ Met Office, and even the French and German met offices)....
These are weather services with real humans, most of whom have years (decades) of maritime meteorology, who use: multiple vessel reports, satellite scans and images, aircraft reports, etc. (as well as dozens of weather ballons, daily), as well as multiple computer models, etc. in order to draw out the weather charts and determine the forecasts...
(and the US National Weather Service ocean meteorologists sign their name to each forecast...putting their personal reputation on the line everyday!)

And, the "Gold Standard" of these are US NWS/NOAA WeFax charts...
These WeFax Charts are WEather Facsimile Charts, drawn by the men and women of those above mentioned weather services....
And, they are available on-line for free anytime, and are transmitted (for free) over HF radio (Marine HF SSB Radio) multiple times each day, for free, by powerful transmitters worldwide...

NWS Radiofax


Here is an updated list showing the worldwide stations...
http://www.nws.noaa.gov/om/marine/rfax.pdf

But, quite honestly, NMF broadcasts WeFax charts that cover the entire N. Atlantic, and will probably be the only station you'd need to tune-in to...(and possibly NMG as you get closer to Caribbean, and/or NMN for HF-SSB Voice weather broadcasts)


b) For your proposed passage, NMF (USCG out of Boston) will be your primary WeFax station....
Here is their daily schedule...
Boston Radiofax Schedule with Links

You may also find NMG (USCG out of New Orleans) to have some useful charts are you get closer to the Caribbean...
Here is their schedule...
New Orleans Radiofax Schedule with Links



And, for HF-SSB Voice weather broadcasts, you will find NMN to provide you very good coverage....
Here is NMN's schedule:
USCG HF Voice


And, also look at WLO's schedule (and set-up an account with them, for easy ship-to-shore and shore-to-ship, phone calls)
HF SSB Radiotelephone, Telex and Email Frequencies and Channels


And, if you wish Hi-Seas text weather forecasts, there are the SafetyNet broadcasts....(much like NAVTEX, for the open-ocean / hi-seas)
USCG HF SITOR



c) If you have an MF/HF-DSC-SSB Radio (such as an Icom M-802 or M-801), you can call other vessels in your area (or region) and upon contacting them, request some weather info / forecasts....
(decades ago, this used to be normal operating procedure on VHF Ch. 16, when on the high seas and seeing a large ship, you'd call them on Ch. 16, and get a nice updated weather report/forecast....but, nowadays unless you have 'em in sight and they're actually monitoring Ch. 16, you're going to need DSC...)



d) Although it is rarely done, in addition to the scheduled broadcasts of these "gold standard" forecasts, you have the ability to "call" some shore stations (such as NMN, on their GMDSS Watch-standing frequencies....WLO, on their own watch-standing frequencies), and request weather forecasts via Voice SSB....
http://www.navcen.uscg.gov/?pageName=cgcommsCall

HF SSB Radiotelephone, Telex and Email Frequencies and Channels



e) If you're a ham radio operator, then use of the amateur radio service (ham radio) can be of help to you in many ways, not just getting weather...
Most of the weather info that you'd get via ham radio will be the same weather info broadcast by NMN (HF Voice Weather Broadcasts)...

Your best place to look on the ham radio bands is 20 meters. and especially 14.300mhz, on the one of the many "nets" on that frequency almost 24 hrs a day....(though, please be aware that radiowave propagation these days and in coming few years will severely limit the use of this band/frequency to only daylight hours and even then might not be too reliable...)

Have a look here:
Maritime Mobile Service Network
The BEST 20-Meter Net Going! | A member of the 14.300 mHz net family.
Welcome to the Pacific seafarer's net | Pacific seafarer's net




6) Okay, now that you've got all the detailed answers you were after...how about some easy-to-understand videos that explain all of this, and show live, real-world use of all of these??
All for free, nothing being promoted, nor sold....just a public service, using a real-world offshore cruising boat and her experienced skipper...

Have a look at these YouTube Playlists....try to watch the videos in the playlists in order, so that everything is more easily understood...

Offshore Weather
https://www.youtube.com/playlist?lis...zdjTJjHlChruyY


Offshore Sailing (Atlantic Crossings)
https://www.youtube.com/playlist?lis...KgTCj15iyl6qoY



Maritime HF Communications
https://www.youtube.com/playlist?lis...ZDo_Jk3NB_Bt1y


HF-DSC Communications
https://www.youtube.com/playlist?lis...ga2zYuPozhUXZX




7) Ludo, of course there is more to all of this....but since you were asking a "hypothetical" question, I couldn't get too specific....
And, FYI, I have used all of the above services / stations, while crossing the Atlantic multiple times on my current boat, as well as using many of these on other boats over the years, with my first use of HF WeFax and Atlantic crossing was in the 1970's....

For more info on HF-SSB radio, communications in general, etc., have a look here...
http://www.cruisersforum.com/forums/...tc-133496.html



I do hope this helps...

Fair winds...

John

[ka4wja]

Palarran,
1) You wrote your opinion here, and we assume this is based on your personal (frustrating??) experiences with a modern MF/HF-DSC-SSB Radiotelephone???
And, as such, I will not argue with you, as everyone is entitled to their opinions and Ludo wrote "experience sharing would be appreciated"...

But, I hope you don't mind if I voice my strong opinion in direct opposition, based on both my personal experiences and on the daily use of the GMDSS by 1000's of mariners, every day!

For long-range sailing, ocean crossings, etc., there is little argument that a properly installed and working MF/HF-DSC-SSB Radiotelephone is still a vital part of both communications (safety and routine) and weather dissemination...
These are far from "dinosaur", as they are used by 1000's of mariners at sea, ever day...and with WeFax charts (true synoptic weather charts) being considered the "gold standard" of offshore weather, I cannot understand how/why you'd come to such a radical opinion??
(please see my post above for the details)

MF/HF-DSC-SSB Radiotelephone is a vital part of the GMDSS, as are VHF-DSC-FM, EPIRB's, NAVTEX, INMARSAT-C, etc...
And, synoptic chart dissemination via HF-WeFax is still used by a large majority of commercial offshore mariners everyday...(the figure from the 2012 WMO survey was ~ 85%!!)

Originally Posted by Palarran

IMO, spending one single dollar (euro) towards a system based on SSB is wasting two. It's beyond dinosaur at this point.

I have an Iridium 9555. Unfortunately, it is also somewhat useless as the Iridium Go has passed it. Not because of performance, but based on the data plans you can get. Check out https://www.predictwind.com/iridium-go/ to see the data options. You can get an unlimited data plan (super slow but who cares) for $125 / month instead of a year minimum with the 9555. The price difference pays for the new GO. The Predictwind app is very nice also so this is what we are going to be using.

BUT....
But, what I think is the biggest red herring here is the all-too-common mis-understanding of the question and applications....

This is a discussion about obtaining weather info "on an Atlantic voyage", which I interpret as "how to access weather forecasts, when at sea / offshore, on an Atlantic passage"....
{everyone knows how to access this info on-line / via internet, when on-shore or in port....most will use a good external Wi-Fi system and/or a cellular/3G/4G connection on-board, when in port or in coastal areas....and whether you use the US NWS/NOAA Marine Weather page ( http://www.nws.noaa.gov/om/marine/home.htm ) as your starting point, or some other....you will find all the marine weather info you need in a few clicks of the mouse....but, when offshore and away from the internet, Ludo was asking how/where do you get this info/forecasts...}

Further, it seems that you (and many times, many others) conflate these discussions into a "SSB vs. Sat phone" argument, which is quite odd (and totally disingenuous) as these systems/devices do two completely different things!!!
"SSB" is a broadcast system (one-to-everyone) and "sat phone" is a one-to-one system....(and trying to use a sat phone in heavy weather and/or for safety comms, is fraught with issues or disaster!)
Many sailors conflate these systems as they are thinking of "data comms", i.e. how can I cheaply obtain some data comms, for e-mail, etc.???
That discussion (which is NOT what this thread is about) is actually NOT about "SSB" at all, but rather is a "PACTOR modem" vs. "Sat Phone" discussion....and while the experiences and opinions are split, it's still a majority that come down on the side of PACTOR....

And, finally, as none of us know what budget Ludo has for his communications equipment, let alone for his weather receiving equipment, it seems to me (in my opinion) slightly disingenuous for someone sailing a large and expensive vessel as Palarran does, to blithely suggest purchasing sat comm gear and then paying a subscription for service, to obtain weather info that is provided for free elsewhere, and for most sailors using sat comm gear (using the raw computer model data in GRIB's), the actual synoptic charts from WeFax prove far superior!!

Now, as I wrote right up front, we are all entitled to our opinions....and I have now voiced mine....
(and, I suspect that while Palarran will disagree with mine, it's very possible that you've misunderstood and conflated the questions and applications here....as this isn't a discussion regarding data comms, but rather how to get good weather info at sea / on passage)




2) Ludo, please read my earlier post (post #14) as well as what I write immediately above here....and, please understand three very important things...
a) Sat comm when at sea (especially in heavy weather) is problematic unless you spend a good deal of money....yes, the IridiumGO is a nice product and Iridium is a great company, but to forego a working MF/HF-DSC-SSB radio and think the IridiumGO is a "replacement" is a serious mistake, as they do 2 completely different things!!
b) HF-WeFax is free, it is easily received by even a simple $100 portable radio (or your IC-7000), for free...and will give you the "gold standard" of offshore weather info/forecasts...
c) E-mail connectivity is NOT needed to obtain reliable and accurate weather info/forecasts at sea, offshore...
And, most sailors actually find no need for e-mail at sea, instead simply forego e-mail for the few days to a couple weeks that they are on passage...

Please take note that these 3 things are facts, not opinions...
(yes, some have good experiences with sat comm at sea, and some have found the IridiumGO to be a great device, but it is not a substitute for long-range comms gear, such as HF radio....and it is not designed nor intended to be so!)

Originally Posted by ludo.verhavert

Thanks to all of you for the good advice !
I definitely will look into the Iridium-go option , and also contact Sailmail.
The advantages of e-mail , over live broadcast in a rough sea acompanied by some radio noise , are obvious . Thks for pointing this out.
I am a radio HAM , so I enjoy contacts with fellow HAM's even at sea.
But I fear that my ICOM7000 is too sensitive to battery voltage drops when transmitting , and not really fit for the agressive marine environment.
I may try to find myself some second hand marine transceiver and Pactor modem ( of which there seem to be quite a few models , hence which one ?)

Thks for the info and good winds to all of you .
Ludo

Ludo, if you have some specific need to maintain e-mail connectivity while at sea, offshore (such as running a business, while out-at-sea???), then a PACTOR IV modem (~ $1600 to $2000 USD) would be a great choice...or a full Iridium system, with external antenna, etc...
And, if for some reason you required "internet access" while at sea (don't know anyone that actually does require this), figure at least $5000 for sat comm gear, and then very large ($1000/month) monthly fees!!

If you wish further discussion on these other topics, please let us know, and we can delve further into them....




Ludo, since your query was "hypothetical", I suspect that what you are really after is this:
"what do I need to have, what do I need to do, in order to get good weather forecasts when at sea / offshore??"
And, that is what I answered above in post #14, and here....
Hope it helps!


Fair winds...

John