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Quiet tropics--for now

By: Dr. Jeff Masters, 1:51 PM GMT on July 26, 2006

The disturbance in the Gulf of Mexico has moved far enough on shore that it no longer has a chance to become a tropical depression. This system will bring heavy (and welcome!) rains to portions of Texas and Louisiana over the next two days.

Tropical Depression Daniel has decayed into a swirl of low clouds, and is expected to dissipate before reaching the Hawaiian Islands. All the Hurricane Hunter flights scheduled to investigate the storm have been canceled.

A tropical wave a few hundred miles east of the northernmost Lesser Antilles Islands is moving west to west-northwest at 15-20 mph. The amount of thunderstorm activity associated with this wave has increased over the past day, as the dry Saharan air surrounding the wave has gradually diluted. However, the wave is now under 30 knots of vertical wind shear. This wind shear is being created by the counter-clockwise flow of air around an upper-level low pressure system to the north of Puerto Rico. This low is not expected to move much the next five days, and should continue to create hostile wind shear over the wave. The wave will spread showers and gusty winds to Puerto Rico on Thursday, and the Bahama Islands on Friday and Saturday. By Saturday, as the wave approaches Florida, it will not be as close to the upper-level low, and the shear may lessen, potentially allowing some development. The wave is expected to turn north towards the Carolinas and not enter the Gulf of Mexico.


Figure 1. Water vapor image from 8:15 am EDT today shows a tropical wave surrounded by dry Saharan air approaching the Lesser Antilles Islands. The brown colors show the driest air, and whites and blues show where the most moisture is. You can see a large swirl of moisture north of Puerto Rico that marks the counter-clockwise rotating upper-level low pressure system that is bringing hostile wind shear over the tropical wave.

Long range forecast
The past four runs of the GFS model have consistently shown a powerful Cape Verdes-type hurricane forming off the coast of Africa August 3, tracking westward, and hitting the northernmost Lesser Antilles Islands on August 7. While I will be amazed if this forecast verifies--since our computer models are not very talented at forecasting tropical storm formation one day in advance, let alone a week or ten days in advance--it does serve as a reminder that we are entering August next week, and we should not be surprised if these most dangerous of hurricanes start forming from tropical waves coming off the coast of Africa.

Jeff Masters

The views of the author are his/her own and do not necessarily represent the position of The Weather Company or its parent, IBM.

Reader Comments

Sorry if this has been covered already -- I realize I am coming into conversations very late.

As a resident of St. Croix and only 90 miles from PR, the sat image of the "smear" wave moisture, dry air and upper level low (ULL) would have to have flattened out an enormous amount of curvature to describe the ULL as being north of Puerto Rico. Its position, as my untrained eyes see it, is almost directly east southern FL and the Bahamas, which puts the ULL at quite a sizeable distance to the north east of PR and the USVI. Does someone know the coordinated for that ULL in that photo? I'd love to confirm or correct my perception about location with an actual tracking map.

From the upper front lines of the big Antilles smear, which made its arrival around 6:30 pm, the winds don't feel like they are picking up in any significant way. There's been a joyous drop in air temps as thunderstorms with lots of lightning (and thunder a pretty decent distance behind based of the lag time between the flash and the rumble. We've had brief bursts or downpours but so far its mostly been much welcome steady rain with the feeling that we get when we have a great day of trade winds. Local forecast said the storms will become a little less scattered and a bit stronger, but that right now the smear isn't going to increase in intensity as it passes over the USVI and PR. Like Dr. Masters, local meteorologist Super Dave said it is the well defined wave/blob that just rolled off the African coast needs to be watched closely as it potentially may develop into our first real threat of the 06 season.

Again, this is all amateur impression not based as yet on any science beyond reading this blog and replies, plus sitting on my veranda watching the rain and the blowing of tree fronds/leaves/branches and listenng to the rain on the roof.

Thanks to any who help me locate the coordinates of that ULL.

--CC
washingaway...Okay. I lived out on St. Charles back in the early 70's. Yeah I'm the old fart here. Been back many times since. Not since Katrina.
St. Charles Ave. faired very well.
Still looks great.
CrucianCrip...Thanks for your questions. I'll help if I can. I am only an amateur myself. Doesn't mean I know nothing...just I do not represent the NHC or any other weather service.

Go to this link and click on the rainbow shot or any other listed under Lat and Long.
Give this a try and get back ok?
washingaway...That's what I understand. The garden district held up ok. Makes my heart hurt for the rest. Hope you are ok.
I did fine, only lost the fence.
washingaway...I am so happy to hear that. I have so many pleasant memories of the City. Spent some time in Covington also. A lot of trips over the causeway!
CrucianCrip...Try this. I did not give you the correct link.

Hit this link and go to the water vapor loop that allows you to turn on the lat/lon. Sorry.
Still a lot of issues here. If another one comes, I don't what will become of this great city.
What's up crip?
washingaway...It is a great and historical part of America's history. One great city. I hate what has happened. I haven't been there since 1993 in the fall. Lunch at the Two Sisters and cruising around the quarter. What could be better?
come on back will have brunch. the sisters are open!
washingaway...I'm happy to hear that! What happened to Jackson Square?
Nothing, looks brand new. I was there this past weekend. Where are you now?
washingaway...I'm in SE Florida. Stuart. North of Palm Beach.
Randrewl..I've notice there's a lot of nuts come in here. Almost decided not to perticipate. How long have you been here and what should I expect.
All global warming issues as well as heat wave information is available on my personal blog. Just click on my screen name and you are there. Nite all!
good nite Randrewl
: washingaway...There's a few of "those" occasionally I have been in that category. Mostly a lot of very fine level headed persons that are interested in tropical weather. I love a heated debate and I can find that here. But nothing is ever personal. You should hang out....you'll learn a lot if you don't know already.
Thanks, I have been reading for some time now, have already learned a lot. see you later.
Thanks Randrewl, those images did help.

Accounting for the time lag between the 8:15am blog image and the recent NOAA photo, the counterclockwise ULL sat at about 55W and ~30N, while STX is at 64.5W and ~18.3N. PR is 90 mls NW of STX, around 65.2ish W and ~19N. So it still seems to be a stretch to refer to that ULL north of PR when it's almost equally as far to our east as it is to our north.

Thanks again for the link to the NOAA pics with long/lat markings.

That took the last of my tired braib so it's bed tims for this Crip. See y'all tomorrow.
National Oceanic and Atmospheric Administration
Climate of 2001
Summer Heat in the U.S.

National Climatic Data Center, 08 August 2001

Temperatures were cooler than average in the eastern U.S. during July with relatively mild conditions prevalent across much of the eastern third of the nation and parts of the West. However, extreme heat and humidity began to build across the central U.S. due to the presence of a persistent ridge of high pressure. Daily highs greater than 90 and 100 F were common throughout much of the Central Plains in July with above average heat continuing into August. With dew point temperatures above 70 F in the same region, heat stress index readings soared well above 100 F in many locations. Although temperatures and humidity levels have been much above average, the number of deaths resulting from this summer's heat has not approached the magnitude of heat waves of the recent past. The 1995 Chicago heat wave resulted in more than 400 deaths . In the disastrous heat wave of 1980, more than 1250 people died across the U.S. as the direct result of extreme conditions, with an estimated 10,000 deaths related to heat stress.



Blogger note here: How many perished in Katrina? Nowhere near the over 11,000 deaths pointed out in the above article due to heat! Think about it people.
1024. Fshhead
Man, you are a curious one!!!!!!!!!!!!!!!!
1026. IKE
This hurricane season continues to be slooooooooowwwwwwwwwww. None of the models have anything on the horizon.

Day 57....

123 to go and it's over.
nice string of "blobs" reaching all the way to the coast of africa i see

good morning everyone waitig for the bad stuff here in pr.
1028. IKE
Correction.....126 days to go.
Morning ya'll.

Ike, it really is not that slow. This is about average for a normal season. About half of those days left are the peak of the season also. Also note that the CMC has gone back to trying to develop a very weak system out of the Antilles blob, which if not for the shear would have already developed.

See ya'll later
StormJunkie.com
here is a radar for you guys to look at if your boredLink
Hurricane Warning


There are maps, satellite images, advisories, and my analysis about Tropical Depression Emilia in the Eastern Pacific.

Tropics are now fairly quiet worldwide.
that "against the wind" report is nice but you guys in the states really need to change how you build houses concrete is the best way to go, and i don't mean cinder blocks talking about reinforced solid concrete walls
Stormtopp: THIS IS WRITTEN IN STONE ( using A PLASTIC KNIFE AND WATERCOLOR PAINTS which wash off in the rain ) .

Bwahahahhahha! WTF?
1035. JKC
Lots of rain in the VI overnight. The next heavy batch is starting now on St. Croix. Winds over 40MPH in the mountains(1000' Up).
Curious about the waves off Africa now. Also interested in the new long range forecast indicating a Hurricane the first 10 days in August. Any more info on that.
thanks turtle another link in my favorites damn its getting long! lets see... cimms...wonderblog..noaa.com... oh yeah storm junkie the list just goes on and on thanks guys :)
jkc i know what you mean about the long range, we have to keep an eye on it but don't hold your breath these predictions change evry 6 hours or so, i have noticed the other blobs and though shear is high it bears mentioning that agust is around the bend and we are seeing activity on the rise plus the forcast tracks even though they could change i would like to point out that these predidcted paths bring them awfully close to pr and bvi's
Good morning everyone,

and a special "hola, sr. puertorico - hace mucho mal tiempo hoy all".

This wave looks like it's going to bring a big blow and some heavy showers also to Hispaniola, especially the north part of Republica Dominicana . . .

And I am planning to stay HOME tomorrow. LOL
oh yeah wanted to ask if anyone has heard about nasa's ambitious plan for studying the birth of hurricanes
buenos dia baha que tal. And yes and what sucks is i have to go to cosco today and start buying stuff for an office party i am going to get so wet :(
the gfs develops a storm off the african coast in 6 days
1042. SLU
Morning to all

The 06z long range GFS looks worrying ... it spins up 4 consecutive lows off africa in the next 2 weeks or so. If this forecast verifies, then we will be in for a long August.

Long range model forecast show trends and they are trending towards a classical Cape Verde-type hurricane season as i anticipated this year.
you guys in the states really need to change how you build houses concrete is the best way to go

THANK YOU!!!!! I have been saying this for ages! We are very lowlying here in the Bahamas but we often sustain LESS damage than FL from the same storms because the bulk of our buildings are now built from concrete . . . mind u, we have a lot of concrete block construction, so I am not sure how well the poured concrete slab housing holds up. But it is sure better than the prefab stuff most US housing is built of today!
Pobrecito mrpr . . .

You need to take a good umbrella (though I have found that a good raincoat, shorts, and sandals are better gear for a tropical downpour :o). That radar didn't give much hope for your staying dry.
yeah the blocks are really not the way to go...let me explain why; in a hurricane or over time water is pushed into the concrete permiating throughout the interior of the block after awhile bleeding may occur on the inside of the concrete wall over time this wall will crack and break with reinforced concrete even a wet wall has the strength to stand and though it may crack it will not crumble and topple over. The best and safest way to build a house is by pouring in the concrete with a reinfroced rebarb frame and for godsake NO WOODEN ROOFS! concrete throughout the structure.
1046. ricderr
stormy...another bad prediction..but with the added humor..it was palatable.....and entertaining...good job
thats not good news for us here in the tropics stormw
hi stormw, i am a newbie so forgive the question in advance! the only models i know about are http://moe.met.fsu.edu/tcgengifs/, they only go to 144 hours, where are longer time frame models found, thankx jo
1050. nash28
Good morning everyone. StormW-- Is that Azores High shift to the east?
mrpr,

We haven't had as many problems with storm surge and flooding as one might expect. The soil here is very porous and usually drains very quickly. Also houses are built on poured concrete foundations, with the blocks starting 12-24 inches off the ground. Since the amount of water that settles is usually at / below this level, the damage is less.

I see what you are saying about roofs, though. The most consistent and costly damage here is to roofs. The construction between about 1970 and 1995 has generally been with low profile wood/shingle. I have noticed an alarming trend recently of buildings, especially two storey ones, with high profile roofs like the ones in the northeast US. They have lots of roof area to be destroyed by hurricane winds.
1054. nash28
That would suggest a steering of any potential storms away from the mainland and out to sea.
Yeah baha but the water damage i am talking about isn't from flooding its from the driving rain, rain traveling at or about 100+ can acctually be forced over time say 6h+ through even the best concrete structure thats why i stress reiforcement in concrete.
Isn't there usually an 8:05am Tropical Weather Discussion update from the NHC (or do I have my update times wrong)?
stormw thankx, another question, when talking about the bermuda high moving to the east or west, does it always meander around out there by itself or does the jetstream everyone talks about push it around, jo
its getting windy now i am going to loose power
Good morning everyone.
1060. nash28
Good morning saddle.
Yawn.
No big hurricane on the models anymore. Maybe it'll reappear in a day or two.
Storm - will pray for your son - hope all comes out well with him.
this is the setup.......
Oh honey...that's rough I know. But, he knows he has it and he is getting treatment. I am only familiar with one person personally who has it and they don't take their medication correctly. Like I said, can't help much other than offer up prayers, but sometimes that's the best help people can give. Hang in there.

1069. nash28
Thanks StormW.
Go dust go! Go dust go! I am probably the ONLY person on this blog that will say that. I love the excitement of an approaching storm, but common sense tells me that we are better off without one - so go dust go!
1073. PBG00
hey littlefish gfs has a monster out there long range...but that is really unreliable..but it does show a trens toward more storms forming in the neaxt two weeks.
My daughter is 14. She is severely dyslexic and has other issues stemming from neglect at school and the refusal to acknowledge that as a learning disorder the first four years of school. She also has a thyroid condition and a kidney disorder. Kids don't deserve to suffer do they? They don't understand all the medications, etc. She is the WORST to get to take her thyroid medication saying people will think she is a drug addict.
1075. PBG00
oops sorry for the typos
Well, I know this is a weather blog - sorry guys, but will be thinking about you Storm and that little fella of yours. It will be o.k... somehow, some way, it will be o.k. Hang in there.
1077. Zaphod
Wow! About a thousand posts when almost nothing is going on! It'll be incredible with a big one comes!

I see that Exxon posted a $10B profit this quarter. I bet we won't make it through the day before somebody in Congress is clamoring for laws to punish them. Funny that nobody makes waves about Saudi Aramco's or Iran's profits that fund terrorism, but Exxon makes a few bucks mostly for Americans and everybody takes offense!

Anybody care to prognosticate on weather effects on oil prices this fall? Having hurricane damage to infrastructure would set up a "perfect storm" oil supply situation ripe and ready for Iran to manipulate.

Zap
1078. SLU
On steering...that could be potentially correct...it would depend if it were more eliptical, or more symetrical, whetehr or not a system encountered any trofs along the way to help kick it out, etc. It would also depend on the latitude of the system...if low enough, it could slide under and continue west. It also depends on how strong the system is. When they are fairly weak, the circulations have a tendency to be steered by the lower level flow. As they grow in size and intensity, the steering level gets higher up in the atmosphere

Good analysis STORMW

There are many factors which determine the movement of these cyclones
African dust plumes: comment today in the NYT weather blurb - in SE US this constitutes the largest component of particulate matter in the atmosphere during ~summer months.

What is more boring than the tropics this summer? Judging an intentional walk contest? Anticipating Greenspan's biography? Contemplating Brittany Spears' birthday suit on Harpers' cover?



mrpuertorico, as far as i can tell, the ULL is almost due north of Hisp. and to the nnw of the wave ..... If not for the shear from this feature, the wave in the antilles may already have some organization.....
stormw my thoughts, as a mom and a grandma, are with you and your family thanks for the info on the bermuda/jet stream, jo
1082. ricderr
but Exxon makes a few bucks mostly for Americans and everybody takes offense!
i feel this should read..exxon makes a few (10 billion isn't a few) off of Americas back. the average familly will pay almost 1500 dollars more a year just for fuel..not to mention heating bills and the increase it causes to the price of goods.....and the cost of obtaining...shipping..and producing gas..hasn't changed