Need help to understand the weather

[gamayun]

I've bookmarked this page -- lots of good advice and info on a complicated subject

[Tetepare]

90% of the time the only weather you need to know is the next 12 hours.

Most of this can be found in the clouds https://www.nasa.gov/centers/langley...es-Ch16.r3.pdf

Wherever you are, if there is Doppler radar it can make a world of difference. Too often the NOAA-based weather is 80% chance of rain, chance of thunderstorms, winds NW 12-15. Well, there is a big difference between a few pop-up storms and a major front, but more often than not NOAA weather radio doesn't differentiate until you're in deep trouble or ruined a great sail waiting out weather that doesn't come.

So far as "the big picture" the references already provided suffice.

[MarkJ]

KD you don't say where u r from (but I am using the mobile version of CF and I can't check profiles)

I take it u are in the USA and going to Thailand on vacation?

If so I put it to you that the weather patterns in Thailand are so different to the USA that it becomes, imho, irrelevant to know how to forecast Thai weather. Just get grub files and what reports you can.

Onto the larger post-vacation theory learning: I find the USA weather to be its own globule and learning that is a task in itself. Same with other regions such as Europe or Australia.

Its aa true pain in my feble mind to stand on my head to learn weather from one hemispher to another until u are quite versed in it. Localities etc too make it easier when you know them.

Unfortunately there are very few (just one to my knowledge) who can explain weather so the penny drops: www.tropicaltidbits.com but that only operates in the hurricane season.

Start with a local course or local books.
The science has improved so utterly remarkably that reading a 10 year old book may not help at all.

[Dougtiff]

Wow !, i'm sure jealous, I sailed those waters in the 70'S and 80'S, remember when Pi Pi was a small Muslim fishing village, maybe 50 people lived there, I was probably the first sail boat that anchored inside PI PI Don, Phuket beach was made up of small Losmans and restaurants on the beach, no hotels, great times, fond memories. Weather was never a problem, especially this time of the year.

[SkipMark]

Worth noting that some of the European countries also provide excellent weather forecast maps for free. The Norwegian met institute is my favorite, both local and global:
Kart – yr.no

They use the NOAA global model for their boundary conditions, but they then include additional data sources in their numerical assimilation procedures.

Mark

[gamayun]

Originally Posted by MarkJ

KD you don't say where u r from (but I am using the mobile version of CF and I can't check profiles)

I take it u are in the USA and going to Thailand on vacation?

If so I put it to you that the weather patterns in Thailand are so different to the USA that it becomes, imho, irrelevant to know how to forecast Thai weather. Just get grub files and what reports you can.

Onto the larger post-vacation theory learning: I find the USA weather to be its own globule and learning that is a task in itself. Same with other regions such as Europe or Australia.

Its aa true pain in my feble mind to stand on my head to learn weather from one hemispher to another until u are quite versed in it. Localities etc too make it easier when you know them.

Unfortunately there are very few (just one to my knowledge) who can explain weather so the penny drops: Tropical Tidbits but that only operates in the hurricane season.

Start with a local course or local books.
The science has improved so utterly remarkably that reading a 10 year old book may not help at all.

Way to put a damper on things, Mark Up to now, I had been deluding myself into thinking that if I could just figure out the Pacific west coast system, then I'd have it down pat everywhere else Please keep it to yourself if you know there isn't a Santa Claus either...

[KD on Tropic]

Hi to all of the fantastic people who have answered my plea for help with this weather issue.
I am humbled that you have all taken the time and effort to assist... and I believe that I have enough reading to do to last me a life time...and from what I am reading from the replies... it will take me a life time to begin and unravel the mysteries of the weather

I can only hope that in the future I can assist someone as you have helped me.. my expertise is electrical.... so if you need to know anything.... please let me know.

Please go kindly and may your path forward be all smooth sailing
Have a great Xmas and NY.

[KD on Tropic]

Sorry all.... forgot to add where I am from.... the great land down under.... Melbourne, Victoria, Australia....

Started our 5 year plan 3.5 years ago.... so in 18 months time... we are hoping to be on the love of our life for the foreseeable future.... all the time learning

[ozskipper]

Originally Posted by KD on Tropic

Hi All... am looking for info... website.... books.... tutorials.... on understanding the weather for sailing... but weather in general....
Would like to be able to look at synoptic charts, weather patterns, gribs, cloud formations... and understand them with a higher degree of confidence than I have.... I suppose just have a better "seamanship" understanding of the weather... at present... I think I know enough.... but there is always that nagging thought in the back of my brain box that says you need to know more.

I am like a lot of people.... time poor to be able to be on the water as much as I would like.... I know there is nothing like practical experience to learn.... but if someone could guide me towards some theoretical help now so I can put it to practical use... I would be greatful.

Am off to Thailand to sail around the East coast riviera islands of Koh Chang, Koh Mak, Koh Kood etc. in a weeks time.... never a bad place to sail due to lots of protected areas should the weather turn.... so as a safe haven to learn in... it is perfect.... and this where I would like to get the practical side of "Understanding the Weather class 101" done.

Thanks for any help I may receive... have a safe Xmas, a great New Year... and may all of your travels have smooth seas

First rule of sailing weather.
Know what a cumulonimbus looks like.
Second rule of sailing weather.
When you see a cumulonimbus coming at you, reef!
Third Rule.
Use two reefs to be sure.

Heres a nice little saying that works "most" of the time.
"wind before rain, soon sunny again"

So if a front is coming and you get the wind first, it will most likely be short lived. (as short as a half hour)
If it rains first, then the wind rises, it may stay windy for some time.

[UNCIVILIZED]

There's a lot of good info & resources in the thread thus far, & yeah, most of it's good stuff. Though there are other ways of learning the weather, sans any complex; tools, info, or book studying. Not that I'm implying that they're bad, quite the opposite.
Make sure to gain a good understanding of how High & Low pressure cells relate, & how they create weather. Plus where the traditional, seasonal, big cells are - over the oceans & land, as they're what drives the big picture. Also, learn the how + why, behind various types of terrain features influencing the weather, & or make their own.

For learning the other bits. Get a watch with a built in barometer & barograph, & a good notebook. Keep'em with you all of the time, & before you go to check your baro, write down everything which you; see, smell, hear, taste, & otherwise sense. Atmospheric info which you can pick up via your own senses. Ditto, in terms of how people (or more significantly, animals) are behaving, down to the little details.
Plus; where the wind's coming from, how strong it is, & if it's consistent, gusting, what you can smell on/in it. Info about the clouds, the quality of the light & from what direction it's coming. The clarity of the air & what's making it appear as it is. Subjective humidity levels. Differences in the plants appearances; @ that moment, as well as at other times & under various other conditions...

Then write down what your intuition is telling you the weather will do in; 2hrs, 12, 24, & in a week. Followed by what your intellect tells you for the same time frames, & why you're drawing said conclusions. - And try not to self judge or criticize.

If you can make the time, take 5+ minutes, & do these things every couple of hours. And if you do, I can guarantee that your knowledge of the weather will grow by leaps & bounds, in short order. That, & it gets to be a lot of fun, given all of the learning which takes place, especially as what you're able to percieve grows very rapidly as well. In conjunction with your predictive ability.
It's kind of like a live, mystery tale unfolding all around you, & your "Sherlock Holmes" skills just keep expanding.

Later on, with your journal, you can go back & see (& denote) how well your predictions turned out. And see what you can learn from cross referencing your predictions, with what actually happened. And use the info to hone both your perceptive, & predictive skills. Including understanding all of the signs which you noted, & wrote down earlier.

In doing this, it of course helps, to be away from any major city; rather, either be out in nature, or on the water. As there, there are less artificial sensory influences to dull or fool your senses (at least until you get good at reading weather sign).
Though such isn't a necessity, but it helps to speed the learnin process.

This route takes a bit of time, in order to be able to learn to accurately predict things. But once you start to get it, if it's something which you really pursue, you'll never need the Weather Channel, or man made tools for forcasting again. For short term predictions, or stuff 6 months from now, & even hundreds of miles away.

Yeah, sounds a bit mystic perhaps. But it's worked for all of the native cultures on the planet for millenium, & still does. And the more you learn to "listen" to the signs, the (progressively) more they'll "tell" you.

[Ribbit]

I must admit to being so rusty, 50 gallons of Hammerite might not be enough to sort me out.

A lot revolves around being in the weather enough, to acquire the nose, eyes, and instincts for it. I had managed to acquire those (particularly sharp eyes for what was happening and how fast, on the horizon), but you don't want to be acquiring them in the worst of conditions.

A couple of things a local fishing trawler skipper told me a very long time ago, have turned out to be pretty dependable in my area - the west coast of Britain.

"The deeper the low, the worse the blow" (we want wind if sailing, but knowing when it is likely going to be too much, obviously helps), and one which he emphasised and which did save my butt more than once, "Rapid High after Low, worse to follow", which gave enough time to successfully run for shelter. He did say a couple of more such things, but unfortunately at present I can't remember what they were (maybe they didn't pan out well enough to be worth remembering). You will then be able to see how a High might be much more rapid than usual.

So a barometer, with regular checking, then associating that with what the weather is doing and then does after, tracking it all with changes in the barometer, can be a huge help in acquiring the feel for it all. To get in the habit, write the barometer pressure in your Log Book every time you make an entry (helped by frequent checks between log entries).

Now I don't know how all that fits in with weather circumstances around the World, but add that in with all the really good stuff above that others have posted, and I think you will be off to a great start once you are 'in' the weather.

It's a fascinating subject, as well as important, and it is why I have picked up a cheap SSB receiver to connect to a laptop and be able to pick up all the weather info I need, wherever I am in the World (Navtex, etc).

eta: What's really sad in my area, is the Met Office is now so unreliable, that after 93 years, even the BBC is ditching them. Everything now seems to revolve around local weather situations in Cities, and they can't even get that right any more. This has had a terrible impact on local farmers for example. You have to know when the Sun is going to be shining, to be able to make hay.

[Ribbit]

Originally Posted by UNCIVILIZED

Great post.

.

Just read UNCIVILIZED's post after doing mine, and I couldn't agree more.

It's all about paying attention to the Real World[tm].

That's how I started noticing the arrival of continuing discrepancies between Met Office forecasts and reality, for example as related to temperature.

Rural forecast temperatures in the UK are now consistently 5 to 8 degrees C higher than actual.

This is not good. Their 'explanation' for it is they now just extrapolate City temperatures into surrounding areas (which is a highly localised Urban Heat Island Effect).

Which may go a long way towards explaining more than a few things (e.g. "hottest this" and "warmest that" and "wettest on record", which directly contradicts the experience of those of us that have lived long enough to know different).

No wonder the BBC are ditching them.

[jackdale]

Originally Posted by Ribbit

So a barometer, with regular checking, then associating that with what the weather is doing and then does after, tracking it all with changes in the barometer, can be a huge help in acquiring the feel for it all. To get in the habit, write the barometer pressure in your Log Book every time you make an entry (helped by frequent checks between log entries).

Absolutely. I sail OPBs, so I wear a watch a barometer, and track the pressure and tendency with every log entry.

[NirvanaBob]

Greetings,
I strongly recommend "Modern Marine Weather" by David Burch. You can find the book on www.starpathnavigation.com. David has written a number of very competent books and provides (for example) the weather briefings for transoceanic racers (e.g., Transpac) and is very good. The book title I cited will provide you everything that I believe you seek and more. PS- I am a weather guy, long time/long distance cruising sailor, and transoceanic racing sailor and have no financial interest in recommending this book or website. Cheers, NirvanaBob

[UNCIVILIZED]

A couple of decent weather sites are; www.wunderground.com and it has a LOT of weather monitoring stations. Like 20 - 40 even in many small towns, including weather buoys & all. Plus various types of radar & other real time images. Excellent site, though as with most, you have to dig around a bit.

There's also a HUGE heap of weather links on www.bowmansunion.com so have a look.

And finally, www.Ikitesurf.com which will give you real time, Very localized wind & weather info, in real time. Even more so, if you subscribe, so I'm told. An old GF was into kiting, & suggested the site to me.

But as I (& some others) stated, naught beats being out in the Real world, & tuning up your senses. And for me, the most important one's my nose. As you can smell the changes in marine plant life for hundreds & hundreds of miles, if you're tuned in. And if you know what it's doing, then you know what's coming a Looong way in advance.

Though there are a giant number of other things which factor in as well. Like watching the animals, & their behaviors; in the moment, & over a span of time. - They'll tell you when weather's coming in, 1/2 day+ ahead of time. In addition to being foretellers of what the next season or 3 will be like. And by season, I mean the 3 month type.

Also, in the Ship's Log, regularly noting the atmospheric conditions is key to spotting trends, before the weather actually happens; wind direction & strength etc., baro readings, sea surface temps, air temps, cloud types & their movements...
If you're the on watch crew, you're putting that info into the log hourly, without fail.

Pretty much, you want to re-connect with your inner, cave man/animal roots. And get to the point where those who know you regard you as the weather groundhog... "He sticks his head out of the door, looks up @ the sky, sniffs the air, & can tell you what the weather will be doing in 2hrs or 12".
Such is how I've been described many a time.

Plus, a great way to learn about the weather, is to teach it. Once you start doing that/can do it, then you (have) gained a real good understanding of it. And when people ask you the "why" behind X, or Y which you're telling them, a lot of knowledge about said topics, comes out of your mouth that you didn't even know that you knew.
It makes you think on stuff, consciously & otherwise. Which is REAL helpful, as it means that you're using; all of your senses, & your brain/knowledge, on All levels.


PS: I know that this ain't a racing website, but most folks could learn volumes on weather prediction, weather software, routine, & websites, by hanging out with some of the high end navigators in said sport. As in yacht racing, you live & die by proper weather (& current, etc.) calls.