Understanding Weather Forecasts?

Feb 14, 2014
7,418
Hunter 430 Waveland, MS
I just looked at Capta's link in his post #18. I suggest you all do too.
Note the "blocks" or rectangle for Global weather areas. Why is the Gulf of Mexico so BIG?
Answer: The number of weather stations, buoys, oil platforms, and satellites available to forecast.
Jim...
 
Jul 27, 2011
5,002
Bavaria 38E Alamitos Bay
I wonder where the phrase of "Keep a weather EYE out" came from. I am amazed that sailor of just 40 years ago survived the weather and the sport continues.
Forty years ago there were no PCs, no internet, no GPS, and no cell phones except on "Get Smart." Diesels were truly auxiliary sources of propulsion in sailboats (and there were no portable generators widespread on sailboats). Sailors had to read charts, keep DRs, look through binoculars, and talk on the VHF to marine operators or other to vessels. So, it's no surprise that they also had to "read the weather", etc. If you look at Brian Fagan's famous (at least for Southern California sailors) book, the first chapter describes how one can forecast the weather of the northern California Channel Islands by looking at cloud formations of the area. The "sport" was probably in better condition then than it is now! There were certainly more folks doing it.
 
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capta

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Jun 4, 2009
4,772
Pearson 530 Admiralty Bay, Bequia SVG
Forty years ago there were no PCs, no internet, no GPS, and no cell phones except on "Get Smart."
There actually was a source for weather deep sea 40 years ago. Twice a day WWV/WWVH would update a whole 3 minute broadcast of Pacific/Atlantic deep sea weather at 5 minutes after/before the hour. All one needed was a shortwave receiver and a lot of patience. lol
 
Feb 14, 2014
7,418
Hunter 430 Waveland, MS
I am amazed that sailor of just 40 years ago survived the weather and the sport continues.
That was meant to be facetious:rolleyes:. I guess I should have said 400 years ago.;)

My point is that you can have all the apps, internet, radio broadcasts, carrier pigeons, weather pennants, etc. to help guide you, but it is still YOU, the Captain, that must prepare you boat and your crew for unexpected weather events (or expected for that matter).

Check out the extremely sophisticated, world wide, hurricane path prediction models for Hurricane Matthew.
https://www.wunderground.com/hurricane/atlantic/2016/Hurricane-Matthew (this is time dependent link)
as of 5:00 pm CDT. Note the ever increasing circle of predictability as time progresses. Now that is MACRO weather.:waycool:
Jim...

PS: Kermit that make since if the bird has a fever for sure.:frown:
 
Aug 13, 2012
533
Catalina 270 Ottawa
If you sail off-shore (and if you sail in-shore, as well, but it would be less critical) consider reading (and absorbing the content) of this great book Mariner's Weather handbook by Steve Dashew. It is available as a PDF, but you may want to get a hardcopy.
 
Jul 27, 2011
5,002
Bavaria 38E Alamitos Bay
Note the ever increasing circle of predictability as time progresses. Now that is MACRO weather.:waycool:
Jim...

PS: Kermit that make since if the bird has a fever for sure.:frown:
The ever increasing radius of the circle is one of increasing unpredictability as the initial conditions on which the model is based when the forecast is made essentially "expire." By the way, I believe your word is sense, since you brought it up.
 
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Jul 27, 2011
5,002
Bavaria 38E Alamitos Bay
I thought that since you offered your sense of it all, I'd add my two cents to it too. It may not be worth two cents since it's all nonsense anyway, since the beginning of it--tou-ché!
 
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Feb 14, 2014
7,418
Hunter 430 Waveland, MS
it's all nonsense anyway, since the beginning of it--touché!
Parry and Thrust Thrust....
Dodge opinion as you wish.
I offer my educated opinion freely, thus it is worth what you paid for it!! NonCents.;)
Jim...

PS: Matthew has the top experts and models "baffled" as too rapid changing intensity. They think that this a rare southerly path and their knowledge of deeper water temperatures here are limited. The good news is they predict it will split the islands, the bad news is their mountains will not de-energize the storm as much, leaving the Bahamas with a dangerous storm.
 

Kermit

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Jul 31, 2010
5,657
AquaCat 12.5 17342 Wateree Lake, SC
I save 2 cents by using deodorant under only 1 arm. Since then people can sense 2 scents.
 
Jul 27, 2011
5,002
Bavaria 38E Alamitos Bay
I save 2 cents by using deodorant under only 1 arm. Since then people can sense 2 scents.
Since reading this, I have sent for the two scents version paying two cents only, too; but with no real sense of why too or two!
 
Feb 14, 2014
7,418
Hunter 430 Waveland, MS
I save 2 cents
woodster saves 4, for, fore, four cents :yikes: and does scent reduction every Saturday, which makes sense to him, but insenses his crew.:cowbell:
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On local radio from Biloxi MS, they are warning East Coast to prepare for Matthew NOW!

People here still are very emotional since Katrina and wishing they would have water proofed pictures, old record collection, important documents, heirlooms, etc.
_____
Here is a picture of a home moved 1000 feet by Katrina, note lack of leaves in the trees, this was the spring (April) after the Katrina Fall (Aug) strike. Not flooding like Baton Rouge, or Sandy's storm surge flooding, or just miserable weather effect. ( not to demean LA or NJ but just different if you get a Cat 4 direct hit)
DVC01447.JPG


What do you prepare for if Matthew (Cat 4 today) hit your coast?
Plan NOW!
Jim...
 
Mar 3, 2003
710
Hunter 356 Grand Rivers
Weather today is much more accurate than years ago when I was a pilot in the Air Force. I started learning weather then myself, because my life depended on it. We didn't have satellites in those days and it could be very far from accurate. On a trip from Knoxville, TN to Puerto Rico one time, I flew into and through an unforecasted hurricane! When I got on the other side, I called it in and was pretty ticked off at the weather forecast. I was reporting on HF to McDill at Tampa and th guy I had chewed on said " Sir they just declared that storm a hurricane about 5 minutes ago! There was nothing remotely associated with a storm of that intensity on my official "forecast". I had to rely on a very early radar to pick my way through those cells and got beat up pretty bad. That was in the early 70's. Today, we know when a depression forms off the coast of Africa and can track it on an IPhone!

The Weather Channel came along in the early 80's and I watched it every day to keep the big picture weather in my mind. I also look out the window. I quit flying in the late 80's after having 5 business aircraft all but 1 with radar, and I figured my reflexes and skills just weren't up to my standards, and with business demands I just wasn't focused enough.

I took up sailing and have found the best forecasts are from Sailflow. I also like the Gribs from NOAA and animate them using my INavX app on the IPad. Weather is very local and wind is local, but in the big picture it is pretty constant. You have to look at what has happened, what is current, and get a good animation program to see what will likely happen in the future. I made two crossings with my wife across the northern Gulf of Mexico. She doesn't like offshore and not being able to see land and has some issues with vertigo, so I have to pick a good weather window when she is with me. Both crossings were forecast with waves less than 2 feet and winds less than 10 knots. We had 3-4 foot waves for a short period and winds to 20 knots both times - but of short durations, but the passages were both very comfortable for her as she saw the animations in advance just like I did and realized that weather forecasts are general and an estimate of what to expect. She had her patch on and did great.

If you are complaining about weather today, you just don't know how good you have it compared to just a few years ago. We've gone where you didn't even know a hurricane was there, to wanting to know 3 days out exactly where it will go and what the forecast winds are going to be. With supercomputers, and satellites, it will only get better.
 
Feb 14, 2014
7,418
Hunter 430 Waveland, MS
With supercomputers, and satellites, it will only get better.
I have been investigating the computer models that are attempting to predict Storm intensification, wind speed, rain dump, land impact, ocean traffic, beach destruction, sea food harvest, wild life, etc.

This is the suspected reason Matthew did not follow the best models, surprised the best in scientific field...

Deep Water temperatures of the Southern Caribbean (Matthew's formative path)

The minor storm (at that time, ask Capta who was there) went so far south to put rain on the "Desert Islands" off the north Venezuelan coast.
______
When a storm passes over, it takes its solar energy from the surface waters, but churns up the ocean in which turbulence brings up deeper colder water to cool and temper the storm (intensification forecasts).
______
Matthew took a 3 day pause to "eat the heat" of the that little monitored deep water temperature water area. Thus jump to a momentary Cat 5 as it turned North.

Satellites today are extremely important, but the Hurricane Hunters, weather buoys, and many more sensors still are key.

I flew into and through an unforecasted hurricane!
Did you get your "honorary Hurricane Hunter" ribbon from the USAF?;)
Jim...
 
Oct 22, 2014
21,084
CAL 35 Cruiser #21 moored EVERETT WA
Understanding weather is an important skill for all sailors. It is not a perfect science. It is more so complicated by the bureaucracy of the agencies we trust our lives to for information.
Here are two articles that may provide insight as to the events of Mathews. After the hype here in the PacNW over the past weekend storm some are questioning "Who cried wolf?"

http://cliffmass.blogspot.com/

http://www.nytimes.com/2016/10/23/magazine/why-isnt-the-us-better-at-predicting-extreme-weather.html
 
Feb 14, 2014
7,418
Hunter 430 Waveland, MS
I read them, ty. Most don't know that the best Hurricane model is from United Kingdom and they don't get hurricanes often.
Forecasting storms is easier than NFL football game winners. The problem lies in the size of a hurricane and the final score.
Jim...