Ophelia, wave nearing Windward Islands, and blob near Puerto Rico

By: Dr. Jeff Masters , 8:19 PM GMT on September 15, 2005

Wave nearing Windward Islands
A well-organized tropical wave 850 miles east of the Windward Islands has not improved in organization this afternoon, but still has the potential to develop into Tropical Depression 17 in the next few days. The wave has a decent surface circulation visible on satellite imagery and QuikSCAT satellite measurements, but deep convection is limited. The wave, located near 9N 48W, is suffering from being too far south and from 10 - 15 knots of wind shear. The disturbance is expected to continue moving west-northwest at 10-15 mph the next few days into a region with less shear. The upper level environment is favorable--an anticyclone has formed on top of it, which should provide very favorable outflow for any deep convection that fires up.


Figure 1. Early track model runs for the disturbance that may turn into Tropical Depression 17.

Blob north of Puerto Rico
A pronounced area of thunderstorms has developed north of Puerto Rico this afternoon, in the base of a large trough of low pressure over the Atlantic. This disturbed area lies in an area of uniform easterly winds that will blow the thunderstorms to the west towards Cuba and the Bahamas. Upper level wind shear is currently high over the disturbance--about 20 knots--but is expected to drop once the disturbance reaches the Bahama Islands on Saturday or Sunday. A tropical depression could form then or early next week when the disturbance crosses into the Gulf of Mexico.

Shear values in general over most of the Gulf of Mexico and Caribbean are expected to drop to very low levels favorable for tropical development during the next week, and I think it is likely that we will see a tropical storm in either the Gulf or Caribbean then.

Ophelia
I'm trying to imagine a day when I don't talk about Ophelia moving slowly, but today is not the day. Perhaps tomorrow; the next trough swinging off the East Coast should be able to pick her up and move her out late in the day.

Ophelia is a shell of her former self. The eyewall has disintegrated, and the latest SFMR wind data from the NOAA hurricane hunters shows just a very small area of hurricane force winds over the water. Cooler waters, dry air, and wind shear are all taking their toll on Ophelia, and by the time she races past Cape Cod on Saturday, the worst she will be able to do there is generate wind gusts of 40 mph.


Figure 2. Winds in Ophelia at 12:30pm EDT today measured by the NOAA hurricane hunters.

Storm surge levels observed last night in Bogue Sound, which is the bay between Morehead City and its barrier island, reached seven feet--near the record levels set there from Category 3 Hurricane Hazel in 1954. The storm surge reached 10 feet in some of the smaller creeks in the Neuse River and may have reached 12 feet, a remarkably high storm surge for what was a tropical storm for that area. High storm surges can result from just tropical storm force winds, if they blow over a large area for a really long time, like Ophelia's did.


Figure 3. Storm Surge heights measured in Ophelia.

For those of you who can handle a 1.6Mb animation, the radar loop from Morehead City, NC during the time Ophelia's northern eyewall passed over the city is fascinating. The turbulence created by having part of the eyewall over land and part over water created some smaller vorticies along the inside edge of the eyewall.

While Ophelia did dump it share of heavy rain--around 5 - 7 inches near Wilmington, and over 10 inches around Cape Fear, south of Wilmington--the rain was mostly confined to the coast, and did not cause widespread flooding problems. Ophelia's winds also did relatively light damage--sustained hurricane force winds (74 mph) were only observed at one location, on Cape Lookout near the Outer Banks. The storm surge was what caused the main havoc with Ophelia.


Figure 4. Estimated rainfall from the Morehead City radar for Ophelia's passage.

Jeff Masters

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231. guygee
2:20 PM GMT on September 16, 2005
oriondarkwood - I liked the original Godzilla, he was a metaphor for the atomic bomb, a force of nature unleashed by mankind. Mothra stands in for Typhoons. After awhile, they made it all too cute, and I lost interest in the later sequels.
Member Since: September 16, 2005 Posts: 0 Comments: 3434
230. guygee
2:12 PM GMT on September 16, 2005
gnshpdude - If you mean the text sources (not the graphics loops) then while I am sure they are available on the NHC site, the following site gets updated rapidly, so I like to get them here:

http://twister.sbs.ohio-state.edu/

click "Tropical Wx" on sidebar, then "Tropical Cyclone Model Guidance - Atlantic".

You can find all the model guidance for the whole year.
Member Since: September 16, 2005 Posts: 0 Comments: 3434
229. oriondarkwood
1:27 PM GMT on September 16, 2005
CoconutCreekFLA,

I take it the zilla date was a one time thing (LOL). I never could really get much work done in a home office setting (either working for myself or as a remote worker).
Member Since: July 5, 2004 Posts: 51 Comments: 42
228. gnshpdude
1:23 PM GMT on September 16, 2005
Does anybody know how to get to the tropical depression invest models that Dr. Masters shows on this blog. I can't seem to find it.
Member Since: August 26, 2005 Posts: 0 Comments: 121
227. CoconutCreekFLA
1:17 PM GMT on September 16, 2005
Not a big zilla fan (although I think I dated his cousin once). I have a home office so, while I don't always post, I do check in periodically. When there is something real interesting brewing it's hard to stay focused on work with no boss looking over my shoulder.
226. stormydee
1:15 PM GMT on September 16, 2005
I post at work...but gotta work for a bit..check back later.
Member Since: August 25, 2005 Posts: 39 Comments: 517
225. oriondarkwood
12:43 PM GMT on September 16, 2005
3 things all of them Off Topic (I can't use the weather chat at work so sue me)


1. Watched a oldie but goodie last night Godzilla vs MechGodzilla 2. Any Godzilla fans in the house?

2. Anyone got any pics of themselves up on thier page?

3. Anyone other than me post while at work?
Member Since: July 5, 2004 Posts: 51 Comments: 42
224. watchingnva
11:53 AM GMT on September 16, 2005
stop whining about the president...jesus....this blog is for weather....def. a democrate there. and i dont know what poles are being looked at...but 3 ive seen still have him at 43%...interesting...watching democratic tv are we?
Member Since: September 7, 2005 Posts: 7 Comments: 1536
223. kiwisk8er
9:09 AM GMT on September 16, 2005
Hello
222. Lovethetropics
8:03 AM GMT on September 16, 2005
Helloooo!!!anyone????
Member Since: August 18, 2005 Posts: 236 Comments: 11372
221. guygee
7:20 AM GMT on September 16, 2005
StSimonsIslandGAGuy - Thanks, that was some very interesting analysis of November hurricanes. It is always easier to invoke the "independent, identically distributed" assumption to make the math more tractable, but your observation that the occurance of November hurricanes is highly correlated makes sense on a deterministic level (if conditions are favorable, then odds are they will remain favorable for a little while longer). I've also read (I think from Dr. Gray) that there is almost no correlation between the frequency of early season hurricanes and the frequency of peak season hurricanes.

I would be curious what the correlation length is between hurricanes in the peak season. They seem to come in clusters, with quiet periods in between. Looking out at the tropics now, I'm wondering if we are due for another "burst" of 2-3 storms within the next several days?
Member Since: September 16, 2005 Posts: 0 Comments: 3434
220. WillJax
7:10 AM GMT on September 16, 2005
Hey StSimons, I also just came on to see the advisory. Are we nerds or what?!

johnsonwax, I dont have much time to discuss semantics as I must get some rest, and normal is definitely a word that can be interpreted for hours on end. However, I was using normal in reference to the frequency of hurricane intensity. It is in this sense that Katrina was a deviation from the mean intensity (which is probably around a category 1.x or 2)

"Normal as related to meteorological data published by the National Weather Service are computed as the average value of a meteorological element over a time period."

"Normal is the arithmetic mean of a climatological element computed over three consecutive decades"

I understood what you said, as I hope you understand what I am saying. Goodnight, talk tomorrow.






Member Since: September 7, 2005 Posts: 0 Comments: 33
219. prttyeyez2002
6:45 AM GMT on September 16, 2005
Kill glad your back and safe....Lefty was on earlier..said he had a blast !!! he posted 2 pocs they were on the main WU photo page.
218. THEMUFFINMAN
6:28 AM GMT on September 16, 2005
hey kill i thought he was short all the people hes with are all taller then him lol
217. guygee
6:25 AM GMT on September 16, 2005
johnsonwax - When you speak of physics as a limiting factor I assume you are speaking of atmospheric physics as it exists on Earth now, today. But conditions have changed in the past and will undoubtably change in the future. For example, the existence of loess deposits in various places tells us that the average near-surface wind velocity in the past was very much higher in some geographical areas than it is today.

Some people are "gradualists", who believe the climate only changes slowly, but (and all sci-fi aside) there is some paleoclimatological evidence of rapid climate change that can happen possibly in the span of human lifetimes (not for me though, I'm too old). So I do not rule out the possibility of stronger storms in the longer term, whether it be from natural or anthropologically-caused climate variation. Personally I believe both are in action. Our children and grandchildren will experience what we have wrought.
Member Since: September 16, 2005 Posts: 0 Comments: 3434
216. StSimonsIslandGAGuy
6:24 AM GMT on September 16, 2005
And now Ophelia's pressue is WAY up to 995 mb. And having stayed up to see the advisory it is time for me to go to sleep :)
Member Since: July 7, 2005 Posts: 257 Comments: 21376
215. StSimonsIslandGAGuy
6:22 AM GMT on September 16, 2005
it is like a stochastic phenomena. You can say that ON average a hurricane can reach 920 mb in the Atlantic every other year, and 910 mb every 5 years and 900 mb every 15 years and 890 mb every 50 years *just making these figures up for this example*

Or that at a certain town on a river, the river reaches 5 feet above flood stage every other year on average, 10 feet above every 10 years and 20 feet above every hundred years (the hundred year flood)

You could still get 2 900 mb hurricanes in the same season, or 2 so called hundred year floods in the same year. If such extreme events are randomly distributed through time, they are stochastic. If the extreme events are not random, but are clustered with each other (two 900 mb hurricanes happen in same season because they whole ocean is abnormally warm) or a hundred year flood happens in March and then another one happens in June (because the weather is stuck in a wet pattern causing floods) then the events are associated.

That means that if an exreme event happens, like a severe flood or a super 900 mb hurricane, something is going on that made it happen and that is making it more likely that a similar extreme event will happen again in a short time.

This means that you can use an extreme event to forecast that another extreme event is more likely than average

The most stongly clustered tropical phenomena is November hurricanes--there have been less than 30 hurricanes that have developed in November since 1886 (not counting survivors from October lasting into November) This works out to about one hurricane forming in November every 4 years. But on average, only about 1 in 7 years has a hurricane form in November, but if a hurricane does form, it is far more likely that another will form later in the month. The majority of November hurricanes have formed in years in which November had 2 hurricanes develop. If you just looked at 30 hurricanes in 120 years, you would not expect that there would be nearly as many November hurricane pairs as there are.

So you can say to yourself, there is only 1 chance in 7 that a November will have a hurricane form, but if one does form, the odds are better than 50/50 that you will see another form that same month.
Member Since: July 7, 2005 Posts: 257 Comments: 21376
214. killdevilmax
6:18 AM GMT on September 16, 2005
Me and Lefty looked high and low for Cantore. I wanted to crack some short jokes cause I heard he was shorter than me. He was just a step ahead of us. Next time.
Member Since: August 28, 2005 Posts: 0 Comments: 324
213. guygee
5:50 AM GMT on September 16, 2005
StSimonsIslandGAGuy - I have read about these polar storms, very intense I have heard, but driven by baroclinic processes.
I was wondering how rising ocean temperatures at higher latitudes might affect tropical systems? There seems to be a limit on the lowest latitude where a hurricane can form due to the weakness of the Coriolis Effect, so I was wondering about the opposite effect at higher latitudes.

I do not have a source, but I remember reading somewhere that (relatively)high-latitude tropical systems are more resilent to shear.
Member Since: September 16, 2005 Posts: 0 Comments: 3434
212. johnsonwax
5:47 AM GMT on September 16, 2005
StSimon,

My dad spent a good chunk of 4 years on watch on a submarine up in those seas. He says that it's like nothing you can imagine - the winds, swells, intensity of storms - it's unreal and very much like a hurricane except that the water temp is 40-50 degrees colder, which is a big deal if you're teathered up on the sail.
211. johnsonwax
5:38 AM GMT on September 16, 2005
"but doesn't some beast rise out of the ocean in the dramatic concluding chapter?"

That might just be one of our ballistic missile subs, you know...

As for the Nature article, it's not calling for larger storms than what we've seen, just more major storms. The increase in destructiveness is as much a function of buildup along the coast as more frequent major hurricanes.

Physics largely prevents these things from getting substantially stronger than 200MPH winds, though they can get physically larger. The amount of land that storms must navigate in the Atlantic before a storm reaches the US really impedes Tip sized storms from developing (man, how completely screwed would we be if a Tip sized storm hit the east coast or gulf).

But if the gulf stream is shutting down it'll just be a nonstop stream of storms down there.

WillJax- you're still confusing normal with average. A storm that is not normal would be one that does not form as a storm usually does, does not behave as a storm normally does, that kind of thing. It's something you can excuse away as an outlier, highly unlikely to ever repeat, and therefore something that we really don't need to plan for. That's not the valedictorian, it's the savant. Tip may not be normal - how often do 1100 mile wide storms form on this planet?

Katrina was by all accounts normal. I don't think anybody here believes that the next storm coming across the atlantic couldn't do exactly what Katrina did. She wasn't exceptionally powerful - comparable to a number of other storms in the last decade, though certainly near the top of the scale. She wasn't exceptionally large, again comparable to others. By suggesting that Katrina was not normal, it tells people 'Oh, don't worry yourself, this could never happen again...'.

It's Bush backpedaling on national preparedness. FEMA will never have to meet a Katrina level of preparedness since Katrina wasn't normal. It's crap and not helpful nor responsible for the public.
210. StSimonsIslandGAGuy
5:35 AM GMT on September 16, 2005
Guygee, extratropical depressions form, grow, mature and die all the time in the north pacific and the far north atlantic around iceland. Some storms up there can get VERY deep, like a depression SW of Iceland in December 1986 with a 916 mb pressure and one near the Shetlands off the north coast of Scotland that hit 913 mb (the record for a non tropical system in the Atlantic as far as I know) in Jan 1993. The 1993 storm had sustained winds at sea of 105 kts and destroyed a oil rig in the North Sea off Scotland, killing everyone on it. The area to the east of Iceland is so stormy in winter that the AVERAGE pressure there is below 985 mb in winter!
Member Since: July 7, 2005 Posts: 257 Comments: 21376
209. subtropic
5:34 AM GMT on September 16, 2005
I really don't know. Good question though. I would think if they they were unable to receive treatment as a result of the storm, you could easily make an argument that they would count as a "storm related fatality". You always come up with some interesting questions.
Member Since: August 29, 2002 Posts: 209 Comments: 4434
208. WillJax
5:32 AM GMT on September 16, 2005
HAHAHA! It already has me cracking up! I love watching Sci Fi movies for their comedic value. Some are just absurdly funny.

It is time for my bed to become my bedtime. In memoriam for sweet Gertude Stein!

Gnight guys.
Member Since: September 7, 2005 Posts: 0 Comments: 33
207. StSimonsIslandGAGuy
5:28 AM GMT on September 16, 2005
I wonder if the evacuees who died in TX so far (57) count. Also the 4 people in New Orleans who died from infections of bacteria 'related to' cholera count.

The TX evacuee deaths--some are clearly not from katrina, like a boy who died of an aortic anyuerism after swimming at a local YMCA on a field trip from the dome (a preexisting birth defect). some though have been diabetics and people on dialysis who had their treatment interrupted while in the superdome and have been stressed out since or were badly weakened. Will those deaths count? I wonder.
Member Since: July 7, 2005 Posts: 257 Comments: 21376
206. guygee
5:28 AM GMT on September 16, 2005
WilJax - I liked to read the late great Carl Sagan's journal articles on planetary weather. Certainly the winds howl harder on other planets, if we alter our climate sufficiently then who knows? It is interesting that the Dr. Emanuel also mentions the increasing *persistance* of hurricanes. I don't want to generalize from a datum, but Ophelia sure has been a real champion at fighting off the onslaught of troughs, dry air and shear. Hurricane Kyle seemed to last forever, a real boon for surfers that year here in Florida.

If global warming allows for development of hurricanes at higher latitudes, then I wonder how much the increased Coriolis effect at the higher latitudes plays a role in making these storms more resilent and persistant in the face of adverse conditions? Perhaps a good question for Dr. Jeff.
Member Since: September 16, 2005 Posts: 0 Comments: 3434
205. subtropic
5:22 AM GMT on September 16, 2005
st simons. I looked an I don't get it either. There are also 2 in Ohio. It could be (operative word is COULD) something obscure. When Irene came up from the Florida straights, we had one fatality in SOuth Florida. A woman stepped in a puddle that was energized by a downed power line, but it counted. Maybe something like that in those other states?
Member Since: August 29, 2002 Posts: 209 Comments: 4434
204. StSimonsIslandGAGuy
5:20 AM GMT on September 16, 2005
It's a Gertrude Stein storm WillJax. As she said about Oakland, CA "There's no there there."
Member Since: July 7, 2005 Posts: 257 Comments: 21376
203. prttyeyez2002
5:19 AM GMT on September 16, 2005
your welcome subtropic.....dont know why I checked there but I did.... :)
202. StSimonsIslandGAGuy
5:18 AM GMT on September 16, 2005
WillJax, if you ever want some laughs, watch "Maximum Velocity" the next time SciFi channel has it on--features a hurricane triggered by the close approach of an asteroid (don't ask, it is all so stupid) with a 612 mb pressure and 500 kt winds.
Member Since: July 7, 2005 Posts: 257 Comments: 21376
201. WillJax
5:17 AM GMT on September 16, 2005
Lefty you've got to fill as in on all the details tomorrow. You guys are now the Cantores of the blog!

Have you guys seen the infrared of Ophelia? There's nearly nothing remaining.
Member Since: September 7, 2005 Posts: 0 Comments: 33
200. StSimonsIslandGAGuy
5:16 AM GMT on September 16, 2005
WillJax, about the storms that became hurricanes 5 times--I heard it mentioned on Accuweather, but I have not researched it myself. I am looking back on the database now at certain long lived storms I remember, but none have hit hurricane status 5 times that I found.

On another note, this entry about Katrina in wikipedia is BIZARRE. I noticed yesterday that hundreds of Katrina deaths were listed as being in Kentucky, and just assumed that some goofball had just posted some nonsense in the article. But looking just now the Kentucky fatalities are still there. What is up with that?!

http://en.wikipedia.org/wiki/Hurricane_katrina#Death_toll_.28summary.29
Member Since: July 7, 2005 Posts: 257 Comments: 21376
199. leftyy420
5:15 AM GMT on September 16, 2005
alright yall i am out catch yal tonm. once again sory i only hve a few pics but wil make sure i take more picsin the next storm i chase. realy was mad at myself wehn i forgot my pic as the sights on hateras were just awsome
Member Since: August 24, 2005 Posts: 35 Comments: 1987
198. subtropic
5:13 AM GMT on September 16, 2005
lefty. Get some sleep man. Let us know when you have them on your blog.
Member Since: August 29, 2002 Posts: 209 Comments: 4434
197. leftyy420
5:12 AM GMT on September 16, 2005
oh ok i duuno i just uploaded them. i am tired so i will make sure the others are on my blog when i put them up tomm
Member Since: August 24, 2005 Posts: 35 Comments: 1987
196. leftyy420
5:11 AM GMT on September 16, 2005
i have a couple more that killdevilmax tok that i wll post tomm. i hve around 10 pics of the beach at high tide but thats on my regular 24mm advantix camera so i wil develop the film later this week nd post hem than. we decided to go t hatteras in a hury and i left my camera in my car so i do not have many pics from there other tan the 4 kildevil tok. must say its a sight to see the sand blowing off the dunes and covering the road in 6-10 inches of sand. killdevil was sliding all over the place but tha man can drive. he gtus to the tip as far asyou can go in a good 50-60 mph wind ad battleingthe sand an the rain. was a hell of a trp
Member Since: August 24, 2005 Posts: 35 Comments: 1987
195. subtropic
5:10 AM GMT on September 16, 2005
Thanks prttyeyez2002. I didn't think to look there.
Member Since: August 29, 2002 Posts: 209 Comments: 4434
194. prttyeyez2002
5:09 AM GMT on September 16, 2005
Lefty I seen the pics...they are on the main WU photos page not in your blog.
193. WillJax
5:09 AM GMT on September 16, 2005
Okay lefty is awake. Sorry lefty.

Guygee, that is an interesting article. I wonder if it foreshadows the creation of a category 6, or perhaps a super- hurricane status.



Member Since: September 7, 2005 Posts: 0 Comments: 33
192. subtropic
5:08 AM GMT on September 16, 2005
ok let's try something. Can you see mine?
Member Since: August 29, 2002 Posts: 209 Comments: 4434
191. leftyy420
5:08 AM GMT on September 16, 2005
yeah i can see them
Member Since: August 24, 2005 Posts: 35 Comments: 1987
190. leftyy420
5:07 AM GMT on September 16, 2005
willjax i am so tired i can't even think about another storm lol. i slept maybe 7 hrs in 48hrs andmost of that was in my car. on the way home i made it t he nc/va border when i decided to pull over and take a nap as i could not focus to drive. caught a 3 hrs nap and made i he rest of te way home. i wil be getting off in a sec just finishing eating dinner my wife made for me so i had a hot meal when i go home.

i am still finding sand on me eevn after a long shower lol
Member Since: August 24, 2005 Posts: 35 Comments: 1987
189. guygee
5:07 AM GMT on September 16, 2005
weatherwannabe - I've fallen a little behind in my bible-thumping, but doesn't some beast rise out of the ocean in the dramatic concluding chapter?

I think the feds should have sent Pat Robertson to N.0. before Katrina hit, then he could have prayed it away just like he did before!
Member Since: September 16, 2005 Posts: 0 Comments: 3434
188. subtropic
5:06 AM GMT on September 16, 2005
lefty, I take it you can see them just fine?
Member Since: August 29, 2002 Posts: 209 Comments: 4434
187. leftyy420
5:05 AM GMT on September 16, 2005
it says images approved dunno why u guys can't see them
Member Since: August 24, 2005 Posts: 35 Comments: 1987
186. WillJax
5:04 AM GMT on September 16, 2005
St Simons, some storms have reached hurricane status five times? Do you happen to know the names of the storms?

I'm wondering if such storms ever developed into major hurricanes, or if they spent their existence as borderline hurricanes such as Ophelia.

I assume that Lefty is taking a well deserved rest. He had better rest up because it's gonna be a busy week.
Member Since: September 7, 2005 Posts: 0 Comments: 33
185. leftyy420
5:04 AM GMT on September 16, 2005
i think some one has to approve it so it won't be up till tom most likely
Member Since: August 24, 2005 Posts: 35 Comments: 1987
184. leftyy420
5:03 AM GMT on September 16, 2005
yeah one pic isme leaning into 50-60moh wns geting hit by sand that realy hurts. its not the fine sand that hurts. its when u get a gust around 70 they pick up the small rocks and pummel u with them

the other pic is me beside a dune staying out of the wind infront of killdevilmax's 4 wheel drive truck now named "storm chaser 1"
Member Since: August 24, 2005 Posts: 35 Comments: 1987
183. StSimonsIslandGAGuy
5:01 AM GMT on September 16, 2005
neither do I lefty.
Member Since: July 7, 2005 Posts: 257 Comments: 21376
182. subtropic
4:59 AM GMT on September 16, 2005
lefty, I don't see them yet.
Member Since: August 29, 2002 Posts: 209 Comments: 4434
181. weatherwannabe
4:58 AM GMT on September 16, 2005
guygee , like everthing else, scientific or not, that study will be highly politicized by the neocons and therefore by Bush. I guess the researchers jsut didn't read enough of the Bible.

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Dr. Masters co-founded wunderground in 1995. He flew with the NOAA Hurricane Hunters from 1986-1990. Co-blogging with him: Bob Henson, @bhensonweather

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