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Re: [Amel Yacht Owners] Re: Predict Wind
Patrick McAneny
Alan, What you and Bill wrote has enlightened me in regards to PW ,and I now will look at it differently from when I purchased it. I will assume it should be viewed more as a suggestion of what to expect ,more than a prediction .
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Thanks,
Pat
SM#123
-----Original Message----- From: divanz620@... [amelyachtowners] To: amelyachtowners Sent: Thu, Sep 13, 2018 3:30 am Subject: [Amel Yacht Owners] Re: Predict Wind As Bill says, you have to remember that this data GFS PWG ECMWF PWE is all theoretical. Models are just that they are not forecasts....they are algorithm generated numerical models
A good forecaster looks at the models but makes assessments based on many other factors to provide a forecast.
GRIB files (which is what these are) can give you an "idea" of what might be happening in the near future.
In my experience even when they all agree, this data is only valid for about 3-4 days.
In the Pacific the models are notoriously inaccurate especially around land forms, isolated islands etc.
Predict Wind claim that their enhanced models take this into account, but in my experience other than when there is a steady trade wind flow, they're not that accurate.
...The wind speeds are frequently underestimated by PWG and overestimated by PWE in my locale. About the only th
ing you can almost depend on is the direction...but close to landforms that not always true either....We have seen PWE and PWG give completely different wind directions at the same time.
Even the top forecasters don;t always get it right.
BUT in terms of cyclones / hurricanes, as Bill says, the models just can't deal with those highly concentrated weather events.
One needs to look at all the available information, models, weather charts, forecasts ( from forecasters...not buoy weather etc) and try to decide what is most likely and make plans on that.
One of things that happens with all this scrutiny here in the S Pacific when heading S ahead of the cyclone season is what they call "Analysis Paralysis"...so much information and conflicting data that no-one does anything !
We look for what's mostly likely suitable weather and then go....you get what you get and
you should be able to deal with it....hurricanes aside.....
Cheers
Alan
Elyse SM437
Noumea
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Re: [Amel Yacht Owners] Hurricane
Patrick McAneny
Danny, The Chesapeake Bay will have little to no impact from the hurricane. Most damage will be limited to the N and S Carolina coastline and inland many miles. It is due to come ashore Friday, with tidal surge as high as 13 ft. on top of high tides and then large waves on top of that. We dodged that bullet, at my age I don't need the excitement . I feel for those in the way,the flooding will be bad. I guess you are in Alaska by now, enjoy your trip.
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Thanks,
Pat
SM#123
-----Original Message----- From: simms@... [amelyachtowners] To: amelyachtowners Sent: Wed, Sep 12, 2018 9:59 pm Subject: [Amel Yacht Owners] Hurricane Hi Pat and others in the line.
How are all you guys situated with that hurricane coming in. Feel for you all. Wishing you all the best.
Danny
SM 299
Ocean Pearl
On 12/09/2018 04:24, "Patrick Mcaneny sailw32@... [amelyachtowners]" <amelyachtowners@...> wrote:
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Re: [Amel Yacht Owners] Hurricane
Alexandre Uster von Baar
Thinking of you Kent.
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Sincerely, Alexandre --------------------------------------------
On Thu, 9/13/18, Kent Robertson karkauai@... [amelyachtowners] <amelyachtowners@...> wrote:
Subject: Re: [Amel Yacht Owners] Hurricane To: amelyachtowners@... Date: Thursday, September 13, 2018, 2:50 AM Thanks Danny,It looks like mostly rain in St Michaels MD and the northern Chesapeake.The docks at the boat yard Iin Cambridge are not adequate in anything more than a 2-3 ft storm surge. Kristy was due to be hauled in two weeks, so I had her hauled yesterday instead. This storm will be devastating for the eastern half of N and S Carolina. I hope others have all gotten out of her way. KentS/V Kristy SM 243
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Re: [Amel Yacht Owners] Hurricane
All the best Kent, I hope it goes well for you
Cheers Alan Elyse SM437
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Re: [Amel Yacht Owners] Hurricane
Thanks Danny,
It looks like mostly rain in St Michaels MD and the northern Chesapeake.The docks at the boat yard Iin Cambridge are not adequate in anything more than a 2-3 ft storm surge. Kristy was due to be hauled in two weeks, so I had her hauled yesterday instead. This storm will be devastating for the eastern half of N and S Carolina. I hope others have all gotten out of her way. Kent S/V Kristy SM 243
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Re: Predict Wind
As Bill says, you have to remember that this data GFS PWG ECMWF PWE is all theoretical. Models are just that they are not forecasts....they are algorithm generated numerical models
A good forecaster looks at the models but makes assessments based on many other factors to provide a forecast. GRIB files (which is what these are) can give you an "idea" of what might be happening in the near future. In my experience even when they all agree, this data is only valid for about 3-4 days. In the Pacific the models are notoriously inaccurate especially around land forms, isolated islands etc. Predict Wind claim that their enhanced models take this into account, but in my experience other than when there is a steady trade wind flow, they're not that accurate. ...The wind speeds are frequently underestimated by PWG and overestimated by PWE in my locale. About the only thing you can almost depend on is the direction...but close to landforms that not always true either....We have seen PWE and PWG give completely different wind directions at the same time. Even the top forecasters don;t always get it right. BUT in terms of cyclones / hurricanes, as Bill says, the models just can't deal with those highly concentrated weather events. One needs to look at all the available information, models, weather charts, forecasts ( from forecasters...not buoy weather etc) and try to decide what is most likely and make plans on that. One of things that happens with all this scrutiny here in the S Pacific when heading S ahead of the cyclone season is what they call "Analysis Paralysis"...so much information and conflicting data that no-one does anything ! We look for what's mostly likely suitable weather and then go....you get what you get and you should be able to deal with it....hurricanes aside..... Cheers Alan Elyse SM437 Noumea
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Re: [Amel Yacht Owners] Re: Predict Wind
This forum is just nothing short of very impressive for this sort of knowledge and comment. It makes me want to take Carango off the market and go sailing again.
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Thank you. Peter Forbes Carango Amel54#035 La Rochelle 00447836 209730
On 13 Sep 2018, at 01:01, Patrick Mcaneny sailw32@... [amelyachtowners] <amelyachtowners@...> wrote:
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Re: [Amel Yacht Owners] Fwd: Seat photos in boat.
Ours doesn't, it is firmly locked in place.
I don;t think I want a swiveling nav seat. Cheers Alan Elyse SM437 Noumea
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Re: [Amel Yacht Owners] Re: House Battery Balancing and Farewell for 2018
Yes that's when you have them all interconnected.
Our batteries aren't interconnected, we have a balancer for each set of 4 x 6V batteries. Cheers Alan Elyse SM437 Noumea
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Re: [Amel Yacht Owners] Re: Predict Wind
Patrick McAneny
Bill , You should work for PW , you better explained the models and how the forecast are derived than their contact reps did. It still concerns me how inaccurately the winds are predicted. I will have to assume that all wind predictions may well be underestimated by a considerable degree.Thanks for your time to explain.
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Pat
SM#123
-----Original Message----- From: greatketch@... [amelyachtowners] To: amelyachtowners Sent: Wed, Sep 12, 2018 7:11 pm Subject: [Amel Yacht Owners] Re: Predict Wind Pat,
PredictWind has four different models that it presents. The first two are the GFS and ECMWF which are the two major worldwide weather models. Nothing about these models is special to PredictWind, these are exactly the same two models that virtually EVERY weather forecast agency all over the world uses. ECMWF tends not to show in many "free" weather programs because you have to buy the results from the European Center for Mid-range Weather Forecasting. The output from the GFS model is free to all from NOAA.
The other two models are the PWG and PWE are the PredictWind's "enhanced" versions of the output from the GFS and ECMWF models. I have not found them to be significantly more helpful than the actual model outputs. I do not understand exactly what PW does to create this output from the major models.
In comparing model outputs to the & quot;real world" data, there are many things that can make them look different. Starting with the fact that the most violent parts of a very large hurricane are actually a rather small weather feature on a global scale. PredictWind averages conditions over significant areas, and this can significantly impact the numbers. In the highest resolution data available from PredictWind it still averages data over 50km. That is a very large area when you are talking about a hurricane, where the highest winds are in a very narrow band around the eye. To take this to an extreme example, PredictWind can not tell you about the wind speed in a tornado, it is too far small. It's the same with a hurricane, although it obviously does better.
The GFS model itself only works internally to a resolution of 28km. ECMWF model works at a higher resolution internally (9 or 10km, I think). So the models actually calculate a LOT more data than PredictWind presents, but they are still an approximation--at best--of what a real hurricane looks like.
Another issue is that it is not always clear about what wind number we are actually talking about. Is the the 1 minute average? the 3 minute average? the surface wind? The wind at 10 meter elevation? All these numbers can be very different. I don't know which of these numbers PredictWind presents. I don't really care, for the way I use the program. Many times the m
edia presents the biggest number they can find because they sell more advertising that way.
I always caution people when they look at GRIB files created by computer programs. They look so PRECISE, it is so tempting to trust them. They have none of the caveats that and weasel words that come from weather forecasters. But these are NOT weather forecasts, and they are NOT reporting current conditions... they are the inputs that are used to create weather forecasts.
Bill Kinney
SM160, Harmonie
Annapolis, MD, USA
---In amelyachtowners@..., wrote : I bought Predict Wind a few months ago and a Iridium G
o to download offshore. I found it to under report winds with TS Gordon by a large margin,like 50%. Now with the Hurricane Florence and sustained winds of Cat4 140 mph reported for the last two days ,Predict Wind is showing from 68mph on PWG to 102 mph on GFS. Since this is a well reported storm I don't understand the under reported wind speed . Is PW generally this far off, can it be relied on? I asked PW about this and basically they said , that their models are"not geared to predicting hurricanes." I do not understand this explanation , a hurricane is simply a low pressure system, their models are not geared to predict low pressure systems ? I have been looking at their models and comparing them with known conditions. So far it is not reassuring , has it been found to be reliable ?
Thanks,
Pat
SM#123
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Re: Predict Wind
greatketch@...
Pat,
PredictWind has four different models that it presents. The first two are the GFS and ECMWF which are the two major worldwide weather models. Nothing about these models is special to PredictWind, these are exactly the same two models that virtually EVERY weather forecast agency all over the world uses. ECMWF tends not to show in many "free" weather programs because you have to buy the results from the European Center for Mid-range Weather Forecasting. The output from the GFS model is free to all from NOAA. The other two models are the PWG and PWE are the PredictWind's "enhanced" versions of the output from the GFS and ECMWF models. I have not found them to be significantly more helpful than the actual model outputs. I do not understand exactly what PW does to create this output from the major models. In comparing model outputs to the "real world" data, there are many things that can make them look different. Starting with the fact that the most violent parts of a very large hurricane are actually a rather small weather feature on a global scale. PredictWind averages conditions over significant areas, and this can significantly impact the numbers. In the highest resolution data available from PredictWind it still averages data over 50km. That is a very large area when you are talking about a hurricane, where the highest winds are in a very narrow band around the eye. To take this to an extreme example, PredictWind can not tell you about the wind speed in a tornado, it is too far small. It's the same with a hurricane, although it obviously does better. The GFS model itself only works internally to a resolution of 28km. ECMWF model works at a higher resolution internally (9 or 10km, I think). So the models actually calculate a LOT more data than PredictWind presents, but they are still an approximation--at best--of what a real hurricane looks like. Another issue is that it is not always clear about what wind number we are actually talking about. Is the the 1 minute average? the 3 minute average? the surface wind? The wind at 10 meter elevation? All these numbers can be very different. I don't know which of these numbers PredictWind presents. I don't really care, for the way I use the program. Many times the media presents the biggest number they can find because they sell more advertising that way. I always caution people when they look at GRIB files created by computer programs. They look so PRECISE, it is so tempting to trust them. They have none of the caveats that and weasel words that come from weather forecasters. But these are NOT weather forecasts, and they are NOT reporting current conditions... they are the inputs that are used to create weather forecasts. Bill Kinney SM160, Harmonie Annapolis, MD, USA ---In amelyachtowners@..., <sailw32@...> wrote : I bought Predict Wind a few months ago and a Iridium Go to download offshore. I found it to under report winds with TS Gordon by a large margin,like 50%. Now with the Hurricane Florence and sustained winds of Cat4 140 mph reported for the last two days ,Predict Wind is showing from 68mph on PWG to 102 mph on GFS. Since this is a well reported storm I don't understand the under reported wind speed . Is PW generally this far off, can it be relied on? I asked PW about this and basically they said , that their models are"not geared to predicting hurricanes." I do not understand this explanation , a hurricane is simply a low pressure system, their models are not geared to predict low pressure systems ? I have been looking at their models and comparing them with known conditions. So far it is not reassuring , has it been found to be reliable ? Thanks, Pat SM#123
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Re: [Amel Yacht Owners] Predict Wind
I’ve found winds to be higher than expected a couple of times, Pat...like 10 it’s stronger. But PassageWeather.com also under-estimated them.
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Kent S/V Kristy SM243
On Sep 12, 2018, at 6:15 PM, sailw32@... [amelyachtowners] <amelyachtowners@...> wrote:
I bought Predict Wind a few months ago and a Iridium Go to download offshore. I found it to under report winds with TS Gordon by a large margin,like 50%. Now with the Hurricane Florence and sustained winds of Cat4 140 mph reported for the last two days ,Predict Wind is showing from 68mph on PWG to 102 mph on GFS. Since this is a well reported storm I don't understand the under reported wind speed . Is PW generally this far off, can it be relied on? I asked PW about this and basically they said , that their models are"not geared to predicting hurricanes." I do not understand this explanation , a hurricane is simply a low pressure system, their models are not geared to predict low pressure systems ? I have been looking at their models and comparing them with known conditions. So far it is not reassuring , has it been found to be reliable ? Thanks, Pat SM#123
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Grease for oil seals
Patrick McAneny
I am going in install three new oils seals and a new wear bushing . I have for years been using wheel bearing grease,I have never had any leaks. However, I saw a mention of silicone grease being used. Would that be better ,is this what is supposed to be used? Thanks, Pat SM#123
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Predict Wind
Patrick McAneny
I bought Predict Wind a few months ago and a Iridium Go to download offshore. I found it to under report winds with TS Gordon by a large margin,like 50%. Now with the Hurricane Florence and sustained winds of Cat4 140 mph reported for the last two days ,Predict Wind is showing from 68mph on PWG to 102 mph on GFS. Since this is a well reported storm I don't understand the under reported wind speed . Is PW generally this far off, can it be relied on? I asked PW about this and basically they said , that their models are"not geared to predicting hurricanes." I do not understand this explanation , a hurricane is simply a low pressure system, their models are not geared to predict low pressure systems ? I have been looking at their models and comparing them with known conditions. So far it is not reassuring , has it been found to be reliable ? Thanks, Pat SM#123
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Re: [Amel Yacht Owners] S/V Rascal
Not only free 🍺 24/7 (great with your morning shower) but free happy hours 6-9 M-W-F. For what more could sailors ask? Former Navy hurricane hole, too, We can have a mini-Amel rendezvous to make up for it being unlikely to make it to St. Michaels by boat (may have to drive). Craig & Katherine SN 68 Sangaris at Brunswick Landing Marina, GA for the duration. ---In amelyachtowners@..., <Itsfun1@...> wrote : Brunswick Landing Marina is an excellent hurricane hole they have nice facilities and free 🍺 Courtney svTrippin Grenada 🇬🇩
On Sep 12, 2018, at 9:22 AM, John Clark john.biohead@... [amelyachtowners] <amelyachtowners@...> wrote:
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Hurricane
Danny and Yvonne SIMMS
Hi Pat and others in the line. How are all you guys situated with that hurricane coming in. Feel for you all. Wishing you all the best. Danny SM 299 Ocean Pearl
On 12/09/2018 04:24, "Patrick Mcaneny sailw32@... [amelyachtowners]" <amelyachtowners@...> wrote:
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Re: [Amel Yacht Owners] S/V Rascal
Brunswick Landing Marina is an excellent hurricane hole they have nice facilities and free 🍺
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Courtney svTrippin Grenada 🇬🇩
On Sep 12, 2018, at 9:22 AM, John Clark john.biohead@... [amelyachtowners] <amelyachtowners@...> wrote:
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Re: [Amel Yacht Owners] S/V Rascal
John Clark
Hi Rick, if you run south I would go all the way down to Florida. Some predictions have Florence making a weird turn south all the way to Savanna before going ashore. John SV Annie SM37 Chaguramas Trinidad
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Re: [Amel Yacht Owners] S/V Rascal
Patrick McAneny
Rick, I meant to add that it is good that you are on the south side of the storm ,and so you should not have anywhere near tidal surge or wind that they will just further north. I hope it stays north of you , looks like it will.
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Stay Safe,
Pat
-----Original Message----- From: Patrick Mcaneny sailw32@... [amelyachtowners] To: amelyachtowners Sent: Wed, Sep 12, 2018 8:27 am Subject: Re: [Amel Yacht Owners] S/V Rascal Rick, Sorry about your deal, but get out of there. If you have not seen the latest forecast, they are predicting it to turn SW , maybe going S along coast before turning inland . So that brings it closer to Charleston . Don't waste time replying , but let us know how you make out with the storm ,when you can.
Be Safe and Good Luck,
Pat
SM Shenanigans
-----Original Message-----
From: rickgrimes1@... [amelyachtowners] <amelyachtowners@...> To: amelyachtowners <amelyachtowners@...> Sent: Tue, Sep 11, 2018 10:29 pm Subject: [Amel Yacht Owners] S/V Rascal Hello Amel Friends,
With mixed feelings about selling, we recently asked you to
identify anyone you knew who might be interested in buying Rascal. Happily, we received a number of inquiries
and had a contract soon thereafter.
However, we couldn’t come to agreement on price and the
buyer reneged. So we are happy to keep
sailing until a serious buyer comes along—perhaps referred to us by one of you. Updated details about Rascal can be seen here.
Rascal is berthed at the Charleston City Marina, SC though we are likely to leave tomorrow morning to flee the wrath
of Hurricane Florence!
Rick and
Linda Grimes
ASM2K #404
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Re: [Amel Yacht Owners] S/V Rascal
Patrick McAneny
Rick, Sorry about your deal, but get out of there. If you have not seen the latest forecast, they are predicting it to turn SW , maybe going S along coast before turning inland . So that brings it closer to Charleston . Don't waste time replying , but let us know how you make out with the storm ,when you can.
toggle quoted messageShow quoted text
Be Safe and Good Luck,
Pat
SM Shenanigans
-----Original Message----- From: rickgrimes1@... [amelyachtowners] To: amelyachtowners Sent: Tue, Sep 11, 2018 10:29 pm Subject: [Amel Yacht Owners] S/V Rascal Hello Amel Friends,
With mixed feelings about selling, we recently asked you to
identify anyone you knew who might be interested in buying Rascal. Happily, we received a number of inquiries
and had a contract soon thereafter.
However, we couldn’t come to agreement on price and the
buyer reneged. So we are happy to keep
sailing until a serious buyer comes along—perhaps referred to us by one of you. Updated details about Rascal can be seen here.
Rascal is berthed at the Charleston City Marina, SC though we are likely to leave tomorrow morning to flee the wrath
of Hurricane Florence!
Rick and
Linda Grimes
ASM2K #404
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