Hurricane Delta

buzd504

frazzdaddy said:

ColbyLang said:

She’s a rapidly growing 4. Hope the cool water just off the coast will weaken it

Not a lot of shear to disrupt her intensification, so that cool water needs to do it's job. Forward speed will be the wildcard. Faster is much better, but does add to wind speed a bit.

Faster forward speed also means less time over cooler water to weaken.

Gulfcoastguy

Higher wind over a short time is less destructive than slightly slower wind that push and pulls on roof fasteners for possibly days. It also dumps less water to soften the ground, help uproot trees, and wash out roads.

frazzdaddy

buzd504 said:

frazzdaddy said:

ColbyLang said:

She’s a rapidly growing 4. Hope the cool water just off the coast will weaken it

Not a lot of shear to disrupt her intensification, so that cool water needs to do it's job. Forward speed will be the wildcard. Faster is much better, but does add to wind speed a bit.

Faster forward speed also means less time over cooler water to weaken.

as I said in my post, but does add to the wind speed of the storm for some.

nolaegghead

....and reduces it for others....

frazzdaddy

Gulfcoastguy said:

Higher wind over a short time is less destructive than slightly slower wind that push and pulls on roof fasteners for possibly days. It also dumps less water to soften the ground, help uproot trees, and wash out roads.

Depends on how high the wind speed is. 

NATIONAL HURRICANE CENTER and
CENTRAL PACIFIC HURRICANE CENTER

NATIONAL OCEANIC AND ATMOSPHERIC ADMINISTRATION

• 
  

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Climatology | Names | Wind Scale | Extremes | Models | Breakpoints

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The Saffir-Simpson Hurricane Wind Scale is a 1 to 5 rating based on a hurricane's sustained wind speed. This scale estimates potential property damage. Hurricanes reaching Category 3 and higher are considered major hurricanes because of their potential for significant loss of life and damage. Category 1 and 2 storms are still dangerous, however, and require preventative measures. In the western North Pacific, the term "super typhoon" is used for tropical cyclones with sustained winds exceeding 150 mph.

Category	Sustained Winds	Types of Damage Due to Hurricane Winds
1	74-95 mph 64-82 kt 119-153 km/h	Very dangerous winds will produce some damage: Well-constructed frame homes could have damage to roof, shingles, vinyl siding and gutters. Large branches of trees will snap and shallowly rooted trees may be toppled. Extensive damage to power lines and poles likely will result in power outages that could last a few to several days.
2	96-110 mph 83-95 kt 154-177 km/h	Extremely dangerous winds will cause extensive damage: Well-constructed frame homes could sustain major roof and siding damage. Many shallowly rooted trees will be snapped or uprooted and block numerous roads. Near-total power loss is expected with outages that could last from several days to weeks.
3 (major)	111-129 mph 96-112 kt 178-208 km/h	Devastating damage will occur: Well-built framed homes may incur major damage or removal of roof decking and gable ends. Many trees will be snapped or uprooted, blocking numerous roads. Electricity and water will be unavailable for several days to weeks after the storm passes.
4 (major)	130-156 mph 113-136 kt 209-251 km/h	Catastrophic damage will occur: Well-built framed homes can sustain severe damage with loss of most of the roof structure and/or some exterior walls. Most trees will be snapped or uprooted and power poles downed. Fallen trees and power poles will isolate residential areas. Power outages will last weeks to possibly months. Most of the area will be uninhabitable for weeks or months.
5 (major)	157 mph or higher 137 kt or higher 252 km/h or higher	Catastrophic damage will occur: A high percentage of framed homes will be destroyed, with total roof failure and wall collapse. Fallen trees and power poles will isolate residential areas. Power outages will last for weeks to possibly months. Most of the area will be uninhabitable for weeks or months.

Gulfcoastguy

Not exactly my first rodeo, that was working with FEMA on the damage evaluation team after hurricane Elena in 1985. Then I carried FHWA along the coast from the West side of the state to the East side 4 days after Katrina. There is a lot that government brochures provided to the public at large say and what we engineers observed. If you have your roof put on correctly (5 tacks per shingle and not too old or correctly installed metal) the main failure points were substandard or corroded fasteners, windows that were covered with plywood or functional shutters, non storm rated garage doors (inside the garage typically only 2 layers of sheet rock separate winds from the inside of the house) , falling trees onto roofs, and storm surge( think tidal wave) . The only help for storm surge is not to build there. All of the others can be addressed. 

ColbyLang

Drifted west dead up my ass. Hope she changes course just a little bit 

buzd504

Gulfcoastguy said:

Not exactly my first rodeo, that was working with FEMA on the damage evaluation team after hurricane Elena in 1985. Then I carried FHWA along the coast from the West side of the state to the East side 4 days after Katrina. There is a lot that government brochures provided to the public at large say and what we engineers observed. If you have your roof put on correctly (5 tacks per shingle and not too old or correctly installed metal) the main failure points were substandard or corroded fasteners, windows that were covered with plywood or functional shutters, non storm rated garage doors (inside the garage typically only 2 layers of sheet rock separate winds from the inside of the house) , falling trees onto roofs, and storm surge( think tidal wave) . The only help for storm surge is not to build there. All of the others can be addressed. 

Note - I am not disagreeing with you, but I will also point out that just because a storm is advertised at 120mph, it doesn't mean you/your property won't experience winds significantly higher or lower at any given period.  Obviously hurricanes can gust much higher at any given moment, as well as spawn tornadoes within the circulation.

frazzdaddy

buzd504 said:

Gulfcoastguy said:

Not exactly my first rodeo, that was working with FEMA on the damage evaluation team after hurricane Elena in 1985. Then I carried FHWA along the coast from the West side of the state to the East side 4 days after Katrina. There is a lot that government brochures provided to the public at large say and what we engineers observed. If you have your roof put on correctly (5 tacks per shingle and not too old or correctly installed metal) the main failure points were substandard or corroded fasteners, windows that were covered with plywood or functional shutters, non storm rated garage doors (inside the garage typically only 2 layers of sheet rock separate winds from the inside of the house) , falling trees onto roofs, and storm surge( think tidal wave) . The only help for storm surge is not to build there. All of the others can be addressed. 

Note - I am not disagreeing with you, but I will also point out that just because a storm is advertised at 120mph, it doesn't mean you/your property won't experience winds significantly higher or lower at any given period.  Obviously hurricanes can gust much higher at any given moment, as well as spawn tornadoes within the circulation.

Great post, nobody is wrong here. It really depends on what you get at LF.
Lot's of factors to consider in the forecasting of this one. Latest guidance from the globals seems to be slowing her down a bit but maintaining intensity through LF. Blip or a trend, we shall see. Recon headed in again.

JohnInCarolina

frazzdaddy

JohnInCarolina said:

We should just nuke it from space.

frazzdaddy

Tomorrows interaction with the Yucatan peninsula will be critical to what Delta does next. Wind shear is forecast to abate so little help there, however an ERC late on the run to La. would be a very good thing. 

thetrim

Fahk

lousubcap

If you haven't figured it by out now, @frazzdaddy is a serious weather and storm hobbiest.  He likely will offer information, details and forecasts that will be more accurate than any you can find elsewhere.  
One more redeeming quality of the scope and breadth of this forum.
Now, if you want the full monty, drop into the Friday forum Zoom session, linked here:
Community And Friday Night Foruming  Definitely an entertaining and learning experience.  

frazzdaddy

Levi Cowen with some good news.

[#NerdTweet] Mid-level shear impacting #Delta diagnosed from the GFS is currently ~30 kt in the 850-400 hPa layer, which is near double what the model predicted yesterday. This is responsible for Delta's currently discombobulated core structure. Last 7 runs valid 8:00pm EDT:

ColbyLang

frazzdaddy

Overnight was not good for Delta

Higher than forecasted wind-shear and land interaction has taken it's toll.
we will see how she rebounds today.

609 
WTNT61 KNHC 071054 CCA
TCUAT1

Hurricane Delta Tropical Cyclone Update...Corrected
NWS National Hurricane Center Miami FL       AL262020
545 AM CDT Wed Oct 07 2020

Corrected header time and time in the summary block

...DELTA MAKES LANDFALL ALONG THE NORTHEASTERN COAST OF THE 
YUCATAN PENINSULA NEAR PUERTO MORELOS...

Satellite imagery, radar data from Cuba, and surface observations 
in Mexico indicate that the center of Delta has made landfall along 
the northeastern coast of the Yucatan Peninsula near Puerto Morelos 
around 5:30 AM CDT (1030 UTC) with estimated maximum winds of 110 
mph (175 km/h), a category two hurricane on the Saffir-Simpson 
Hurricane Wind Scale. 

A WeatherFlow observing site near Puerto Morales recently reported 
near calm winds and a minimum pressure of 972 MB (28.71 inches) in 
the center. 

A WeatherFlow observing site near Cancun has reported peak 
sustained winds of 84 mph (135 km/h) with a gust to 106 mph (170 
km/h). 

SUMMARY OF 545 AM CDT...1045 UTC...INFORMATION
---------------------------------------------------
LOCATION...20.8N 86.9W
ABOUT 20 MI...35 KM S OF CANCUN MEXICO
MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H
PRESENT MOVEMENT...NW OR 305 DEGREES AT 17 MPH...28 KM/H
MINIMUM CENTRAL PRESSURE...972 MB...28.71 INCHES

$$
Forecaster Brown

ColbyLang

Yep, down to a 2, expected to rebound to a 3. We’re prepping for the worst, praying for the best

frazzdaddy

My thoughts are somewhere between Holly Beach and Chenier as a 2 but there is a lot of warm water to cross, so we shall see.

ColbyLang

frazzdaddy said:

My thoughts are somewhere between Holly Beach and Chenier as a 2 but there is a lot of warm water to cross, so we shall see.

This would be absolutely devastating to this area to get two storms back to back. A lot of this area still without power or any repair to their buildings.

frazzdaddy

ColbyLang said:

frazzdaddy said:

My thoughts are somewhere between Holly Beach and Chenier as a 2 but there is a lot of warm water to cross, so we shall see.

This would be absolutely devastating to this area to get two storms back to back. A lot of this area still without power or any repair to their buildings.

I know, Hopefully the EURO is right and it will move west a bit more. 

thetrim

Fahk

ColbyLang

Anxiously awaiting the 10am update.....

Gulfcoastguy

Slightly more to the west. I'm afraid that the rubble is about to bounce. Maybe the strength will drop when it nears shore.

ColbyLang

Yep, 10am has us in Lafayette now on the Eastern side of the eye. Praying @frazzdaddy is right and she walks west again. 

frazzdaddy

ColbyLang said:

Yep, 10am has us in Lafayette now on the Eastern side of the eye. Praying @frazzdaddy is right and she walks west again. 

http://flhurricane.com/modelanimator.php?storm=26&year=2020&title=26

Go in and animate the plots. The trend is definitely west. 10k question is  is does it continue?

ColbyLang

4pm has it downgraded to a Cat 1 and drifting a little closer to me. We’ll be about 40 miles from landfall on the East side. Should make for an interesting ride. 

Gulfcoastguy

Here is the 7 am central projection. Basically increase to a three in deep water, decrease to a two in shallow water, and quickly decrease when it hits land. 

https://www.wunderground.com/hurricane/atlantic/2020/hurricane-delta?map=5day&MR=1

frazzdaddy

#Delta is indeed intensifying this morning as expected. Will likely make another run at becoming a major hurricane today. Perhaps even more concerning, a couple of ERCs and core changes have led to the wind field expanding, which, as predicted, will make surge a big problem. pic.twitter.com/npirJRrVWl

— Andy Hazelton (@AndyHazelton) October 8, 2020

HWRF is also showing this this in the last runs.

Recon this am showing evidence that Delta may be back to a 3 already.

Euro run to put the expected wind field into perspective. 

ColbyLang

Cameron parish landfall projected somewhere around Creole, LA before crossing I-10 at Welsh, LA. Should be a solid Cat 2 at landfall. Go west Delta!