94L a threat to the Lesser Antilles; Gordon a hurricane; Helene hits Mexico

By: Dr. Jeff Masters , 3:24 PM GMT on August 18, 2012

Share this Blog
33
+

A large tropical wave that emerged from the coast of Africa Thursday night (Invest 94L) is located a few hundred miles southwest of the Cape Verde Islands off the coast of Africa, and is headed west at 15 - 20 mph. This storm is a threat to develop into a tropical storm that will affect the Lesser Antilles Islands as early as Wednesday. The storm is under moderate wind shear of 10 - 20 knots, and is over waters of 27.5°C. A large area of dry air lies just to the north of 94L, as seen on the latest Saharan Air Layer (SAL) analysis. This morning's 8:15 am EDT ASCAT pass caught the east side of 94L, and showed a partial surface circulation. Satellite images show just a modest amount of heavy thunderstorm activity, and I expect the earliest that 94L could develop into a tropical depression would be Sunday.


Figure 1. Morning satellite image of Invest 94L.

Forecast for 94L
The latest 8 am EDT run of the SHIPS model predicts that wind shear will be low, 5 - 10 knots, and ocean temperatures will gradually warm from 27.5°C to 28.5°C over the next four days, as 94L tracks westwards towards the Lesser Antilles. As is typical with storms making the crossing from Africa to the Antilles, dry air to the north will likely interfere with development. However, with shear expected to be low, dry air may be less of an issue for 94L than it was for Ernesto or TD 7. The storm should maintain a nearly due west track through Monday night, to a point near 50°W, about 700 miles east of the Lesser Antilles. At that point, a trough of low pressure passing to the north of 94L may be able to pull the storm more to the northwest, as suggested by the latest 06Z (2 am EDT) run of the NOGAPS model, and by three members of the GFS model ensemble forecast (Figure 2.) However, the models have been trending more towards a solution where this trough is not strong enough to influence 94L's path. This scenario will be more likely if 94L takes its time to develop, since a weaker storm will be smaller and shallower, and less likely to respond to the trough passing to the north. Our two best performing models, the GFS and ECMFW, both take 94L through the Lesser Antilles. The ECMWF, which predicts that 94L will stay weak and not develop, is faster, bringing the storm through the Lesser Antilles on Wednesday. The GFS model is slower, bringing 94L to the Lesser Antilles on Thursday as a hurricane. The models have shown poor run-to-run consistency in both the timing and the track of 94L, so it is difficult to assess which land areas might be most at risk, and when. A database of historical probabilities of storms in the same location as 94L maintained by Dr. Bob Hart of Florida State University reveals that historically, 45% of storms in this location have eventually hit land, with Canada (13% chance) and North Carolina (15% chance) the most likely targets. In their 8 am EDT Tropical Weather Outlook, NHC gave 94L a 40% chance of developing into a tropical depression by Monday morning.


Figure 2. The 00Z (8 pm EDT) run of the GFS model from August 17, 2012, was done 20 different times at low resolution using slightly different initial conditions to generate an ensemble of forecasts (pink lines.) The high-resolution operational GFS forecast is shown in white.

Gordon becomes a hurricane
Hurricane warnings are flying for the central and eastern Azores Islands as Hurricane Gordon heads eastwards at 18 mph. Gordon became the third hurricane of the 2012 Atlantic hurricane season at 5 am Saturday morning, and is sporting an impressive-looking eye on visible satellite loops. Gordon should be able to maintain hurricane status until Sunday, when wind shear will rise steeply to 30 - 40 knots, and ocean temperatures will drop to 25°C. The combined effects of high wind shear, dry air, and cooler waters will likely act to weaken Gordon to a strong tropical storm by the time it arrives in the Azores Islands Sunday night, but the storm will be strong enough to bring damaging winds and heavy rain to the Azores Islands. Gordon is not a threat to any other land areas, and the extratropical remnants of Gordon will not bring any strong winds or significant rain to Europe. The last time the Azores were affected by a tropical storm was in 2009, when Tropical Storm Grace brought 65 mph winds on October 4. No significant damage was reported. Ironically, the last hurricane to affect the Azores was the 2006 version of Hurricane Gordon, which caused minor damage in the Azores, consisting of mostly fallen trees and power outages. However, after Gordon became an extratropical low, four injuries due to falling debris from high wind were reported in Spain, and Gordon brought high winds and rain that affected practice rounds at the Ryder Cup golf tournament in Ireland. About 126,000 homes were without power after the storm in Northern Ireland and one injury was reported.


Figure 3. Morning satellite image of Hurricane Gordon.

Helene makes landfall in Mexico
Tropical Storm Helene made landfall near 10 am EDT as a tropical storm near Tampico, Mexico, with 40 mph winds. Helene's formation on August 17 ties 2012 with 1933 for the 2nd earliest appearance of the Atlantic's eighth tropical storm. Helene's rains should remain south of Texas, but moisture from Helene may feed into a stalled frontal system over the northern Gulf of Mexico and bring heavy rains to the northern Gulf Coast early next week.

I'll have a new post this afternoon, giving a quick global weather summary for July, the 4th hottest July in Earth's history.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

Not only will you be able to leave comments on this blog, but you'll also have the ability to upload and share your photos in our Wunder Photos section.

Display: 0, 50, 100, 200 Sort: Newest First - Order Posted

Viewing: 327 - 277

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14Blog Index

Quoting emcf30:
East Coast DOOM Run

GFS 12Z



Sup E..........LOL at MC at the end. :)
Member Since: Posts: Comments:
Quoting Grothar:


I know, I did a number of blogs on it last night on the late shift. I think you may have been on.


yea I remember, I do not think we have written the last chapter on her
Member Since: Posts: Comments:
Quoting Grothar:


Wheat crackers are for the cheeses. LOL How you doing aqua?

Looks like they want something in the Gulf at the same time 94L is nearing the Islands

..yes the Nam at 60 hours shows something there too this morning earlier..could change
Member Since: August 6, 2011 Posts: 4 Comments: 40978
How do I know a hurricane is going to approach the eastcoast? Answer: September is coming up soon!
Member Since: Posts: Comments:
Hurricane Donna approaching the Florida KeysThis is a radar image of Hurricane Donna over Florida Keys.
Member Since: Posts: Comments:
Quoting Hurricanes101:


that something is Helene



I know, I did a number of blogs on it last night on the late shift. I think you may have been on.
Member Since: July 17, 2009 Posts: 71 Comments: 26867
Will check back later this evening on 94L........Have a great day folks.
Member Since: Posts: Comments:
Quoting Bayside:
They say the best place to be ten days out is under the eye, guess I'll find out. Going to Germany for two weeks, this is really making me nervous.
In that case, I guess this one is going out to sea... lol

Quoting Chicklit:
#232: Oh No Baha, not that one!
We've got beach erosion bad enough now.
I can't help feeling the GFS is picking an old storm at random from the archive and using its track as the latest model run... lol

Quoting hydrus:
Reminds me of Donna, just further south..
Think I saw this one on one of the earlier model runs...

Member Since: October 25, 2005 Posts: 19 Comments: 22576
Quoting weathermanwannabe:


True. We saw the same thing recently with Ernesto when some of the earlier models took it into the Gulf then things changed as usual. Kind of hard for me to fathom folks posting tracks already from past storms suggesting that this will do the same..........Every storm is different.

On the supplies front, most folks should have the basics covered already and wait until 3 days out to wrap up the list including gas, plywood, if the 3 day track is headed your way. On my "final" list is the deviled ham spread.............Love that stuff and reminds of when I was a kid......... :)



Just don't buy Spam. ugh. I still have nightmares of that stuff.

Not much change

Member Since: July 17, 2009 Posts: 71 Comments: 26867
Quoting stormchaser19:
94L not so fast XD
HAARP to the rescue
Member Since: Posts: Comments:
Quoting Grothar:


Wheat crackers are for the cheeses. LOL How you doing aqua?

Looks like they want something in the Gulf at the same time 94L is nearing the Islands



that something is Helene

Member Since: Posts: Comments:
Quoting gugi182:
If and i mean "IF" 94L barrel's down in to the Lesser/Greater Antilles by late or the middle of next week what type of storm will the potentially "ISSAC" will be:

a) Tropical Storm
b) Strong Tropical Storm (70mph)
c) Minimal Hurricane Cat.1 (75mph)
d) Category 2
e) Category 3
f) Category 4
g) Category 5
h) Open Wave


C. cat 1, but still a long way out
Member Since: Posts: Comments:
anyone have the 8am coordinates and numbers on 94L

atcf site is very hard for me to access on the computer, been using my phone, but I am out of data until tomorrow morning so I cant go look lol

Thank you in advance
Member Since: Posts: Comments:
Quoting SLU:

Can't post HTML as an image animation on here. Just have to link it.
Member Since: July 6, 2010 Posts: 113 Comments: 32528
Quoting gugi182:
If and i mean "IF" 94L barrel's down in to the Lesser/Greater Antilles by late or the middle of next week what type of storm will the potentially "ISSAC" will be:

a) Tropical Storm
b) Strong Tropical Storm (70mph)
c) Minimal Hurricane Cat.1 (75mph)
d) Category 2
e) Category 3
f) Category 4
g) Category 5
h) Open Wave


I'm thinking C or D judging by the intensity models.
Member Since: Posts: Comments:
Quoting gugi182:
If and i mean "IF" 94L barrel's down in to the Lesser/Greater Antilles by late or the middle of next week what type of storm will the potentially "ISSAC" will be:

a) Tropical Storm
b) Strong Tropical Storm (70mph)
c) Minimal Hurricane Cat.1 (75mph)
d) Category 2
e) Category 3
f) Category 4
g) Category 5
h) Open Wave

D or E
Member Since: July 12, 2008 Posts: 7 Comments: 383
Quoting aquak9:


Fois de gras goes on wheat crackers, you twit.

Caviar goes on celery.


Wheat crackers are for the cheeses. LOL How you doing aqua?

Looks like they want something in the Gulf at the same time 94L is nearing the Islands

Member Since: July 17, 2009 Posts: 71 Comments: 26867
Quoting MAweatherboy1:
This may get torn up by the islands:



The Islands are not big enough to tear anything up
Member Since: Posts: Comments:
Am surprised by people saying now is the time to make preparations for 94L. Would have thought anyone living in hurricane prone areas would be prepared year round. Since IVAN, my first experience with a hurricane), I have all my supplies in place by June 1st -- water, batteries, tinned foods,plastic trash bags, tarps, bungee cords, etc. These do not get touched until end of hurricane season and then I replenish the following June 1st. Hoping that this one will leave everyone alone.
Member Since: Posts: Comments:
Quoting aquak9:
yo keep
we have no hills in Fla
deforested or otherwise
well then i guess u best start building one
Member Since: July 15, 2006 Posts: 175 Comments: 54858
Quoting StAugustineFL:


Sure we have hills. We call them bridges. :)


In South Florida we call them landfills.
Member Since: March 10, 2006 Posts: 0 Comments: 10572
If and i mean "IF" 94L barrel's down in to the Lesser/Greater Antilles by late or the middle of next week what type of storm will the potentially "ISSAC" will be:

a) Tropical Storm
b) Strong Tropical Storm (70mph)
c) Minimal Hurricane Cat.1 (75mph)
d) Category 2
e) Category 3
f) Category 4
g) Category 5
h) Open Wave
Member Since: Posts: Comments:
305. SLU
Quoting SLU:
Very little doubt in my mind that 94L is already a TD. At this current trend, we could have a TD declared by 5pm ...

Member Since: Posts: Comments:
Quoting aquak9:


no you're wrong! we need to ALERT the east coast- fill up the gas tanks, buy beef jerky, clean the fishing coolers, duct tape the windows- you can never be too prepared!!!


ROFLMAO...

Hey Water Puppy... How is it going?
Member Since: March 10, 2006 Posts: 0 Comments: 10572
Quoting aquak9:
yo keep
we have no hills in Fla
deforested or otherwise


Sure we have hills. We call them bridges. :)
Member Since: Posts: Comments:
Quoting emcf30:


And almost the entire Eastern seaboard. Thank goodness the track will change a gizzilion time from now to then, but, I believe the thinking is right...
We will see a plethora of doom runs for the next 10 days at least since the system behind the one we are watching will be a concern. These storms are along way off.
Member Since: Posts: Comments:
Quoting PRweathercenter:
Is there a tropical cyclone formation alert for invest94 yet?

No.
Member Since: July 6, 2010 Posts: 113 Comments: 32528
ok..its early yet..im thinking of preps..what exactly do i need you ask?.......................Equipment
Flashlights - Buy one for everyone in the home and make sure there of good quality.
Battery powered radio - Am/Fm radio a must. Weather radio is good. Police scanner may come in use after the storm to help keep tabs on looting.
Rechargeable battery-operated lanterns - Candles and kerosene lanterns are fire hazards. You can use them but don't fall asleep or leave them unattended!
Clock - Wind-up or battery-operated
Work Clothing - A clean change of clothes for everyone store in water tight plastic bags.
Rain gear - Find in surplus stores
Sturdy swamp boots - Flooding should be expected.
Sturdy working gloves - You'll need these for the clean up after the storm
TV antenna - An inexpensive model, to use when cable goes out.
Working fire extinguishers - You should have one or two in your home at all times not just when a hurricane is expected. Inspect seal check charge gage. Should be a class ABC!


Consumables Supplies
Extra batteries - Flashlight, lantern, radios, clock.
Extra bulbs - Make sure they fit the flashlights you buy
Toilet paper - I cover everything!
Matches - Good ones, Ohio blue tip, lighters, their cheap get a bunch.
Plastic garbage bags - Get quality for storage, get cheap for trash, double bag garbage, get a bunch.


Documentation
Map of the area - Up to date and use to plan escape avoid rivers and streams.
List of phone numbers - Make this ahead of time and test the numbers.
Homeowners insurance policy - Talk to your agent about your coverage and keep a copy of your policy in a safe place and keep one with you in a zip lock bag.
Life insurance policy- keep a copy of your policy in a safe place and keep one with you in a zip lock bag.
Car insurance policy- keep a copy of your policy in a safe place and keep one with you in a zip lock bag.
Proof of Residence - Your drivers license should have your correct address if not the police may not let you back into the area.


Hardware
Hand tools - Hammer, screwdrivers to use now, shovel and pickax for after the storm
Scissors - What you have may be ok.
Screw gun - You know how I love these things
Plywood - 4 x 8 foot sheets of plywood 5/8 inch to 1/2 inch thick to put over windows. Ask for exterior plywood - you should have this way ahead of time
1/4 machine screw sockets and screws or other hardware - To mount plywood over all windows and opening in your home.
Plastic sheeting to cover furniture - Also good for holes in your roof Rope - You'll need it for something
Duct tape - To waterproof items. Masking tape isn't strong enough and melts when wet. Don't bother putting tape on your windows, that's such a joke.
Canvas tarps - Good for holes in your roof.
Nails - There are many kinds, so look over your home now and determine what you will need. Roofing nails - For holding down plastic sheeting and tarp.
Common nails - for temporary repairs.



OK..so who here doesnt have ANY of this right now?..LOL
Member Since: August 6, 2011 Posts: 4 Comments: 40978
The hype is in Weather Chat right now, if you want to join.
Member Since: September 3, 2011 Posts: 13 Comments: 3476
Quoting Grothar:


You are right. Waaayh too early. Besides, everyone should already have most of their supplies ahead of time anyway. You just have to pick up some last minute essentials like caviar and and wheat crackers.


True. We saw the same thing recently with Ernesto when some of the earlier models took it into the Gulf then things changed as usual. Kind of hard for me to fathom folks posting tracks already from past storms suggesting that this will do the same..........Every storm is different.

On the supplies front, most folks should have the basics covered already and wait until 3 days out to wrap up the list including gas, plywood, if the 3 day track is headed your way. On my "final" list is the deviled ham spread.............Love that stuff and reminds of when I was a kid......... :)

Member Since: Posts: Comments:
yo keep
we have no hills in Fla
deforested or otherwise
Member Since: Posts: Comments:
Is there a tropical cyclone formation alert for invest94 yet?
Member Since: Posts: Comments:
Quoting aquak9:


no you're wrong! we need to ALERT the east coast- fill up the gas tanks, buy beef jerky, clean the fishing coolers, duct tape the windows- you can never be too prepared!!!
jump in the camper head for the hills

hello water puppy
Member Since: July 15, 2006 Posts: 175 Comments: 54858
Quoting emcf30:


That is one of the Analog comparison storms
Analog from who?
Member Since: Posts: Comments:
BTW, anybody notice that David went from TS to Major in 3 days?
Member Since: October 25, 2005 Posts: 19 Comments: 22576
Quoting Grothar:


You are right. Waaayh too early. Besides, everyone should already have most of their supplies ahead of time anyway. You just have to pick up some last minute essentials like caviar and and wheat crackers.


Fois de gras goes on wheat crackers, you twit.

Caviar goes on celery.
Member Since: Posts: Comments:
Quoting VAbeachhurricanes:


my god before I was into weather my mom would duct-tape the windows... maybe the worst experience of my life trying to scrape it off every single window...
and it offers NO protection at all
Member Since: August 6, 2011 Posts: 4 Comments: 40978
Quoting Grothar:


You are right. Waaayh too early. Besides, everyone should already have most of their supplies ahead of time anyway. You just have to pick up some last minute essentials like caviar and and wheat crackers.


And lots of rum, when pottery sends you it.
Member Since: September 6, 2007 Posts: 0 Comments: 6670
......................Just LOOK at the area these storms cover..most if not all of central florida
Member Since: August 6, 2011 Posts: 4 Comments: 40978
Quoting aquak9:


no you're wrong! we need to ALERT the east coast- fill up the gas tanks, buy beef jerky, clean the fishing coolers, duct tape the windows- you can never be too prepared!!!


my god before I was into weather my mom would duct-tape the windows... maybe the worst experience of my life trying to scrape it off every single window...
Member Since: September 6, 2007 Posts: 0 Comments: 6670
Quoting xtremeweathertracker:

It already has that tropical cyclone shape. It just needs convection... It will probably go to 50% at 2PM but IMO should be 60%.
Member Since: Posts: Comments:
Quoting aquak9:


no you're wrong! we need to ALERT the east coast- fill up the gas tanks, buy beef jerky, clean the fishing coolers, duct tape the windows- you can never be too prepared!!!
you are so right here..and do NOT forget..lots of Batteries..you could be without Power for weeks and if it comes ashore..maybe longer than that
Member Since: August 6, 2011 Posts: 4 Comments: 40978
Quoting emcf30:
East Coast DOOM Run

GFS 12Z



Wahaha! You made me snort coffee out my nose!
Member Since: Posts: Comments:
GFS 168..
Member Since: Posts: Comments:
Quoting TropicalAnalystwx13:
I think Gordon is a Category 2 hurricane.



Has about 3/4 of a -60C donut, so it might be there.

Presentation has greatly improved since earlier when the dry finger had intruded, so it's possible intensification has resumed.

Member Since: January 25, 2012 Posts: 33 Comments: 1520
Member Since: May 31, 2011 Posts: 57 Comments: 572
Quoting weathermanwannabe:
Dr. Neil Frank (one of the best) always stated that he did not start to pay close attention (US wise) until a storm reached the Antilles; that was close enough in time to get a better handle on the trof and ridging pattens 2-3 days out. Also, the models were not as sophisticated then as they are now. My point is, disregard the current long-term models showing a potential US impact; we will not have any real idea until the is storm is at the Antilles and the models recalculate all of the variables at that time.

No need to worry(if you are in the US) at this juncture.


You are right. Waaayh too early. Besides, everyone should already have most of their supplies ahead of time anyway. You just have to pick up some last minute essentials like caviar and and wheat crackers.
Member Since: July 17, 2009 Posts: 71 Comments: 26867
Quoting VAbeachhurricanes:


What? Way too early for that....


no you're wrong! we need to ALERT the east coast- fill up the gas tanks, buy beef jerky, clean the fishing coolers, duct tape the windows- you can never be too prepared!!!
Member Since: Posts: Comments:
Quoting Abacosurf:
Wow Largo...you are getting tons of rain today huh...
We had some early coasties this morn down here.
wow yes and more on the way..be careful all this is headed eastward..whew..tons of lightning with it
Member Since: August 6, 2011 Posts: 4 Comments: 40978
Member Since: Posts: Comments:

Viewing: 327 - 277

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14Blog Index

Top of Page

About

Jeff co-founded the Weather Underground in 1995 while working on his Ph.D. He flew with the NOAA Hurricane Hunters from 1986-1990.