• Sailing is all about the Weather.

    Big into the exploration of Atlantic Hurricanes since Katrina came uninvited into his world, James (Jim) Gurley (JamesG161) has followed every Tropical Storm birthed in Atlantic, Gulf and Caribbean waters since. Being a boater, he knows that we often need more time to prepare than we get from the TV weather folk. Jim relies on the science of storm development to share early warning info with friends and fellow boaters.

    Early in 2018, Jim and John Shepard, (JSSailem) started to chat about the weather data available. John asked Jim to help forecast Pacific NW storms, and this morphed into discussions on weather forecasting.

    For John, sailing in the PNW is sometimes hit and miss. One day is ugly, then a string of beautiful days but no wind, followed by a series of blue-sky days and 12 knot breezes. Being ready for those great sailing days means you need to look to the Pacific Ocean and what is brewing. John has been into Pacific NW Weather since the 1970’s when his first PNW November storm hit bringing more than 40 days and 40 nights of continual rain.

    Together we want to share information, new APPs, safety, and thoughts about letting the weather help you. Identify some of the resources for sailors and help prepare you for your next sailboat outing.

    It is far better to go out on the water knowing what to expect in weather terms, than to be out on the water and see dark ominous clouds suddenly appear, unprepared.

Hurricane Dorian <-- TS<--TD 5 <-- Invest 99L

Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
@HMT2 that is one of the many possibilities under consideration, as @capta shared.

It is two early to tell what Dorian will do.
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Any thoughts on if this thing will cut across Florida into the Gulf and power back up?
The models are converging again.

Why are they diverging?
Dorian is still trying to organize and the HIGH to the north are causing the Curve ball.
The Models are disagreeing on the speed of that HIGH movement to the east.

You might notice the models show a ≈120° turn to go behind that HIGH as it passes.

That is the key.

When and where does Dorian turn North?
If in the Gulf, it won't stay long.

Dammit Jim...
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
This may sound a bit trite, but I am hearing the news hype now.:doh:

Dorian is still LOW ENERGY content. Not Category, not Monster, not not not....

It is Solar Energy [water vapor heat] that wants to whack the Land.

The land stops that Energy fueling....

So what?
Dorian is a small compact energy source. The high winds are focused near eye, 40 miles in diameter.
At this time no eye formed, although it is trying, but dry air keeps messing with it. [so say Hurricane Hunters]
_____
Sunday afternoon we will all know more. The hype is to alert you.
Are you Alerted yet?
Jim...
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Looks like it passed Bouy 41046 with a low of 29.61 early this morning.
and the tops winds were? [gust of 46 knots]

Here is my point ...
That Buoy, not in the middle of Dorian but shown by the HH's to be the most Energetic part.
Jim...
 

JRacer

.
Aug 9, 2011
1,331
Beneteau 310 Cheney KS (Wichita)
As long as it keeps its slow pace, we might just make it in and out of MIA Sunday morning before the SHTF.
 
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capta

.
Jun 4, 2009
4,766
Pearson 530 Admiralty Bay, Bequia SVG
As long as it keeps its slow pace, we might just make it in and out of MIA Sunday morning before the SHTF.
The slower it goes the bigger the probability it will grow stronger in the hotter waters it is entering. Slow storm bad, fast storm bad but better.
 

JRacer

.
Aug 9, 2011
1,331
Beneteau 310 Cheney KS (Wichita)
The slower it goes the bigger the probability it will grow stronger in the hotter waters it is entering. Slow storm bad, fast storm bad but better.
Understand that!
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
You might notice the models show a ≈120° turn to go behind that HIGH as it passes.
That turn is a Stall...
So does that Stall help or hurt the storm's Energy content?

Center of storm Stalls over land...

•Energy dissipates in form of a lot of Rain

Center of storm Stalls over Heat suppling Water...

•Energy grows fast
________
You might notice the models show a ≈120° turn to go behind that HIGH as it passes.

That is the key.

When and where does Dorian turn North?
If in the Gulf, it won't stay long.
Jim...
 
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Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Hurricane Fuel is HEAT, not surface Temperatures.
What is the difference?
The surface Temps get blended fast because of wind and waves.

Blended with what?
Lower depth waters.

We have satellites and buoy information that gives temperatures of deeper waters.
By knowing that NOAA gets Heat Potential or Storm fuel.

ohc_naQG3_ddc.gif



Heat units are BTU or Joules.
This show HEAT spread over a surface area like BTU/ sq ft or kiloJoules / square centimeter kJcm(-2)
Now for BIG HEAT look South of Cuba.
______
Not so much on Dorian track, but Why lower?
Dorian is the 3rd Storm that has passed that way this year.;)

Storms de-energize Solar Energy stored waters.
Jim...

PS: a form of Energy is Heat.

PSS: The lower the sea surface area [Centimeters squared] exposed to a storm, less Energy picked up.
PSSS: Dorian is a small diameter storm , so far.
 
Last edited:
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
Dorian Slows down movement to 5 mph and Grows in diameter.

Key to the curving predictions....

Dorian slowed by a HIGH pressure to the North. That HIGH pushed TD Erin out to sea.

What follows a HIGH?:hook2:
 
Oct 22, 2014
20,993
CAL 35 Cruiser #21 moored EVERETT WA
There is always one to raise their hand and volunteer an answer when the Teacher asks a question...:biggrin:
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
I’ll bite! A low.
The winner!!!
______
But Dorian is a lower pressure than that LOW.

So to most forecasting models that LOW seems to be a HIGH. [If that doesn't confuse you, it did the models]

Dorian is turning to follow the path of least resistance.:thumbup:

Jim...
 
Feb 14, 2014
7,399
Hunter 430 Waveland, MS
All the forecast models are adjusting and matching.

Dorian is turning!! :wow3:

Two Hurricane Hunters missions are in the storm now, at two different altitudes.

The storm is very compact 90 miles in diameter.

If the eye stays off shore, damage will be minimized to landlubbers.:pray:
 
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