Changes in Tropical Cyclone Intensity & Track

[chrisr]

Originally Posted by GordMay

“Cyclones in French Polynesia”
➥ https://www.bwsailing.com/cyclones-in-french-polynesia/

“French Polynesia Cyclone outlook”
➥ https://www.sailsouthpacific.com/new...clone-outlook/

many thanks gord

a bit dated and all pretty well known stuff, except the tongan study.

interesting "... No significant long-term trends were found in the number of TCs, severe TCs, and accumulated cyclone energy (ACE) over the period of study..."

i know we are a bit of a backwater compared to eg caribbean but you'd think somebody would have produced something like the tongans

cheers,

[Adelie]

After a bit of cleanup and discussion the mods have elected to reopen this thread.

Keep a lid on the politics or it will be closed again.

[boatpoker]

Anyone noticed that for the last year, weather forecasts have been crap !
We've been caught several times in the last year by totally inaccurate forecasts.

My thinking is that weather is changing so fast that the models are playing catch up and it may be years before they do.

[davil]

Originally Posted by boatpoker

Anyone noticed that for the last year, weather forecasts have been crap !
We've been caught several times in the last year by totally inaccurate forecasts.

My thinking is that weather is changing so fast that the models are playing catch up and it may be years before they do.

===========================================

share your observations.

1) find very difficult to project a 3 days forecast

2) Unusual weather like this past mid-May/mid-June have a 4 weeks long, persistent, uninterrupted NE winds, was stuck in Norfolk heading north, eventually re routed Chesapeake/Delaware Bays to reach Cape May.

Last year almost same but with never ending rain and strong fronts passing through.

Certainly making it more challenging any passage involving more than 100 miles a stretch of unprotected waters.

[Don C L]

Originally Posted by boatpoker

Anyone noticed that for the last year, weather forecasts have been crap !
We've been caught several times in the last year by totally inaccurate forecasts.

My thinking is that weather is changing so fast that the models are playing catch up and it may be years before they do.

I've noticed in my area I am better off when I check and compare 3 or 4 sources. So far Windy and NOAA have been pretty good for correctly predicting SoCal but I trust the 2 or 3 day forecasts more. Just the other day NOAA changed their forecast the day before I was going. Not a big change but I thought that was interesting. I suspect the movement of the big high and the jet stream has the computers confused. Any meteorologists here to help explain it?

[boatman61]

Originally Posted by Ryban

The thread should also have stayed on topic and focused on the science and the forecasting, papers, reports, and models, rather than the lay-person's opinions about such.

You mean like the weather forecaster inside a studio reading out a scientific weather report "winds F2-F3 from the NE, sunny with occasional cloud, sea's slight"
Meanwhile the layman is 10nm offshore and bouncing around in 2 metre sea's in a F5-F6 SW'ly yelling.. "Stick yer head outa the window dickhead"..

[sailorboy1]

Originally Posted by boatman61

You mean like the weather forecaster inside a studio reading out a scientific weather report "winds F2-F3 from the NE, sunny with occasional cloud, sea's slight"
Meanwhile the layman is 10nm offshore and bouncing around in 2 metre sea's in a F5-F6 SW'ly yelling.. "Stick yer head outa the window dickhead"..

science!

[Ryban]

Again, we cannot have a conversation on this topic without it devolving into a sh*t throwing contest.

I think plenty of good science has been presented here, and countered with jokes and anecdotes. If you want to have an actual conversation on the topic of how warming oceans will impact cruisers due to changes in tropical cyclone patterns that's fine. But we seem incapable of doing that, so I'm not going to engage further.

[boatman61]

I've been commenting on how the winds have been changing in the N Atlantic since my first WE crossing in 2000, the E'lies have been spreading to further W and N over the last 10yrs.. my last crossing had me in E'lies N of Bermuda where pre 2010 it was W'lies and Northers.
I do not need science to tell me what's happening, I'm living it.. speculation from computer modelling as to why is another matter, for this layman.

[Don C L]

Originally Posted by boatman61

I've been commenting on how the winds have been changing in the N Atlantic since my first WE crossing in 2000, the E'lies have been spreading to further W and N over the last 10yrs.. my last crossing had me in E'lies N of Bermuda where pre 2010 it was W'lies and Northers.
I do not need science to tell me what's happening, I'm living it.. speculation from computer modelling as to why is another matter, for this layman.

I think that is the point, Boatie; to get some observations in the mix too. Heck even weather forecasters need hurricane hunters to fly into the center of a hurricane to get data! But that is not meant to discredit or diminish the other forms of scientific data collection and analysis, just to add to it, IMO.

[chrisr]

i recall hearing that one reason weather forecasting went to pieces during covid was far fewer planes flying

aircraft gather weather data every flight...all goes into the models

of course that excuse is a bit old now as i think flights are back to pre-covid frequency ?

cheers,

[sailorboy1]

Originally Posted by chrisr

i recall hearing that one reason weather forecasting went to pieces during covid was far fewer planes flying

did it? I didn't notice any change in the correct percentage of weather guessing

[GordMay]

Originally Posted by sailorboy1

did it? I didn't notice any change in the correct percentage of weather guessing

People routinely make snide jokes, about the inaccuracy of weather forecasts.
But, weather forecasts are vastly better, than they used to be, and are continuing to improve. [1]
A modern five-day forecast, is as accurate as a one-day forecast, in 1980.
Modern 72-hour predictions of hurricane tracks, are more accurate than 24-hour forecasts, just 40 years ago. [1]

So though the weather prediction jokes continue, they are growing more and more unfounded, every year.

More extensive observations, much faster numerical prediction models, and vastly improved methods of assimilating observations into models, led to the improvement.
As more advanced weather satellites come online, and faster supercomputers are used to crunch weather data, forecasting will grow even more accurate.

A seven-day forecast can accurately predict the weather about 80 percent of the time*, and a five-day forecast can accurately predict the weather approximately 90 percent of the time.
The one-day forecast is almost perfect all the time now [95 - 98%]. The two-day forecasts are almost as good. The success rate of three-day forecasts, is still at [or above] 90%.
However, a 10-day [or longer] forecast is only right about half the time.

A number of geographic features, such as large bodies of water, and the interplay between global atmospheric circulation patterns, make it more challenging to forecast the weather, in some areas, than in others.

* When you go to 7 days, the weather has had a week to evolve, in a manner that's more difficult to predict; because small errors can magnify, and branch away, from what the actual weather is going to be. The atmosphere is called a ‘chaotic system’ for a reason.
Eg: A 1 km/h error in wind speed, over 24 hours, would mean that bit of air travelled just 24 kilometres away, from where you thought it would be; but over the course of a week, that’s going to be hundreds of kilometres away.

The bottom line is that, if you have reasonable expectations, about how good weather forecasts are, you'll find that most forecasts are quite useful; especially if they're communicated in a way, that emphasizes the parts of the forecast that are more certain, than others.

But, let's face it. Not all weather forecasts are created equal.

[1] “Profitable Prophecy: Advances in Weather Prediction” ~ by R.B. Alley, K.A. Emanuel, and F. Zhang
➥ https://dspace.mit.edu/bitstream/han...v1.pdf?sequenc

[AKA-None]

Is this thread about why weather is different than previous or what to take into consideration when weather planning?

[boatpoker]

Originally Posted by GordMay

People routinely make snide jokes, about the inaccuracy of weather forecasts.
But, weather forecasts are vastly better, than they used to be, and are continuing to improve. [1]
A modern five-day forecast, is as accurate as a one-day forecast, in 1980.
Modern 72-hour predictions of hurricane tracks, are more accurate than 24-hour forecasts, just 40 years ago. [1]

So though the weather prediction jokes continue, they are growing more and more unfounded, every year.

More extensive observations, much faster numerical prediction models, and vastly improved methods of assimilating observations into models, led to the improvement.
As more advanced weather satellites come online, and faster supercomputers are used to crunch weather data, forecasting will grow even more accurate.

A seven-day forecast can accurately predict the weather about 80 percent of the time*, and a five-day forecast can accurately predict the weather approximately 90 percent of the time.
The one-day forecast is almost perfect all the time now [95 - 98%]. The two-day forecasts are almost as good. The success rate of three-day forecasts, is still at [or above] 90%.
However, a 10-day [or longer] forecast is only right about half the time.

A number of geographic features, such as large bodies of water, and the interplay between global atmospheric circulation patterns, make it more challenging to forecast the weather, in some areas, than in others.

* When you go to 7 days, the weather has had a week to evolve, in a manner that's more difficult to predict; because small errors can magnify, and branch away, from what the actual weather is going to be. The atmosphere is called a ‘chaotic system’ for a reason.
Eg: A 1 km/h error in wind speed, over 24 hours, would mean that bit of air travelled just 24 kilometres away, from where you thought it would be; but over the course of a week, that’s going to be hundreds of kilometres away.

The bottom line is that, if you have reasonable expectations, about how good weather forecasts are, you'll find that most forecasts are quite useful; especially if they're communicated in a way, that emphasizes the parts of the forecast that are more certain, than others.

But, let's face it. Not all weather forecasts are created equal.

[1] “Profitable Prophecy: Advances in Weather Prediction” ~ by R.B. Alley, K.A. Emanuel, and F. Zhang
➥ https://dspace.mit.edu/bitstream/han...v1.pdf?sequenc

your link was published in 2019. The weather changes have been drastic since then, they are outdated.