We want to hear from you. Please tell us how we can better serve you by taking this survey.

Quiet tropics; update on Bill Proenza's doings

By: Dr. Jeff Masters , 2:43 PM GMT on June 22, 2007

The tropical Atlantic is quiet today. The low pressure system over northern Florida that brought rain to the state Thursday has moved out to sea and weakened. Wind shear is high over this low, sea surface temperatures beneath it are cool, and I don't expect any development. None of the computer models are showing any tropical development over the next week. Our best chance of a new threat area to watch may not occur until the next strong cold front pushes off the U.S. East Coast. The long range GFS model forecast expects this to happen around Saturday June 30.

Bill Proenza news
In the absence of much to talk about in the tropics, we can always talk about the latest on new NHC director Bill Proenza. The View from the Surface blog is keeping up with the latest. Last night, I listened in to Proenza's comments on the Barometer Bob Show, an Internet radio show. I asked him where he got his numbers of 16% and 10% improvement for 72-hour and 49-hour hurricane track forecasts made using QuikSCAT satellite data (his boss, acting NWS director Mary Glackin, said "I'm not willing to stand by those numbers.") Proenza cited a study done of hurricane tracks from 2003 that showed these improvements, and Margie Kieper is working on getting a copy of this study for the View From the Surface blog. Margie came across a 2006 study which shows that for one storm studied (Hurricane Cindy of 1999), inclusion of QuikSCAT data improved track forecasts at 24 hours and 48 hours by 30-50% (Figure 1). There is also a 2007 study which showed improvements of 25%-50% for 24 hour - 48 hour model track forecasts of 2002's Hurricane Isidore using QuikSCAT data vs. no QuikSCAT data (Figure 2). We'll have more on the ongoing Bill Proenza hullaballo next week, with more info on just how important QuikSCAT is to hurricane forecasting.

Figure 1. Forecast error in the track of Hurricane Cindy (1999) with and without using QuikSCAT data. Image credit: NOAA. Data taken from the 2006 paper, The use of remotely sensed data and innovative modeling to improve hurricane prediction, by Robert Atlas, O. Reale, B-W. Shen, and S-J. Lin.

Figure 2. Forecast error in the track of Hurricane Isidore (2002) with and without using QuikSCAT data. Image credit: American Meteorological Society, "The Impact of Assimilating SSM/I and QuikSCAT Satellite Winds on Hurricane Isidore Simulations", by Shu-Hua Chen. Monthly Weather Review 135, issue 2, pp 549-566, February 2007.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

Sign In or Register Sign In or Register

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: 226 - 176

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18Blog Index

226. pottery2
9:03 AM AST on June 23, 2007
Re; my post on losing 7 points, it does seem that the Carib system was the result of a wave that passed through Trinidad earlier, and I did say then that if it got to 70w it would be interesting to see what it did. I just got back my 7 points. I'm thinking of going into politics.......
225. BoyntonBeach
1:02 PM GMT on June 23, 2007
Let me rephrase. Is the blob watching in the Caribbean unusual for this time of year ? or is the Caribbean setting up with ripe conditions for developement this year ? sst's, shear, etc. ?
Member Since: Posts: Comments:
224. pottery2
9:01 AM AST on June 23, 2007
BAHA. A band from the Carib system ?? I was not on here yesterday, so I did not see that. I did not realise it had affected so far north.
222. BahaHurican
8:45 AM EDT on June 23, 2007
LOL, Pottery . . .

A band from that system passed over us yesterday. Low clouds, black bottoms, a visible line w/ sun on either side. Had me running for cover, but it never actually rained in my neck of the woods. Friends who live on the eastern end of New Providence tell me they got a soaking, though.

I don't mind the no TD for now if it means we still get some rain . . .
Member Since: Posts: Comments:
221. pottery2
8:43 AM AST on June 23, 2007
The wave off Africa will be under heavy manners from SAL to survive. Good to see it though !
220. BahaHurican
8:41 AM EDT on June 23, 2007

Maybe, maybe not. It's too early to tell, really. The likelihood of another powerful storm forming where Wilma did is rather low until much later in the season, say October.

The CAR is the logical place to watch for now; later on (say next month) people will indeed start paying more attention to the twaves coming off Africa.
Member Since: Posts: Comments:
219. pottery2
8:34 AM AST on June 23, 2007
Good morning. OK, so I was WRONG. ( I'm not a politician, so I can say that ) I suggested that the system in the southwest Carib basin would end up as a TD around 20n 80w. Well it obviously did not. ( back to the drawing board for me, with 7 de-merit points )
Actualy, I have to admit that it was all a nefarious plot to buy up real estate in the Caymans for cheap, by encouraging Kman and Caymanite and those guys to sell out and run. Oh well...........
218. BahaHurican
8:37 AM EDT on June 23, 2007
That's the one, FLboy. That storm destroyed my greatgrandparents' home and farm on Long Island, and one of my greataunts died indirectly as a result. She swallowed a bonefish bone, which stuck in her throat and putrified. (People here don't usually eat bonefish for the very reason - horrible hard to remove bones - but the bonefish was all they could catch, and they ate it since nothing else was available.)
Member Since: Posts: Comments:
217. BoyntonBeach
12:40 PM GMT on June 23, 2007
That's my point. Not 1 wave has survived for more than what ? a day or so ? and a lot of attention has been to the activity in the Caribbean. Are we going to get a monster from the same area that formed Wilma ? when conditions improve (more into the core of the season) ?
Member Since: Posts: Comments:
216. BahaHurican
8:21 AM EDT on June 23, 2007
In fact, my storm database counts 29 storms forming or passing within 300 miles of 60W 15N (making it very likely they originated as African waves)that formed in July. Many of them became hurricanes.

I'm not trying to say it WILL happen. I'm saying it's not an unusual event.
Member Since: Posts: Comments:
214. BahaHurican
8:15 AM EDT on June 23, 2007
Baha, you mean to tell me that you have to go way back to 1926 to find a Cape Verde hurricane in July?

LOL No, I can go back to 2005 . . . Dennis and more particularly Emily formed from Cape Verde waves that were tracked across the ATL.

I picked the 1926 hurricane because it was a cat. 4 hurricane that hit almost every island in the Bahamas and that devastated the town of Nassau. The storm that hit Miami a few weeks later didn't do as much damage here, mainly because there wasn't much left TO damage . . . Anyway, it is a storm I immediately remember.

Member Since: Posts: Comments:
212. weatherman94
8:05 AM EDT on June 23, 2007
i give it
10% td
5% ts
1% hur

the sal is very strong
Member Since: Posts: Comments:
211. StoryOfTheCane
11:56 AM GMT on June 23, 2007
itll get to the Caribbean one way or another, so the SAL being strong might actually be a bad thing in regards to potential landfall if it develops
Member Since: Posts: Comments:
210. StoryOfTheCane
11:55 AM GMT on June 23, 2007
Member Since: Posts: Comments:
209. hurricane23
7:50 AM EDT on June 23, 2007
I would agree with the trends of some very impressive waves of the african the past few weeks but as ive been stateing if the parade of trofs of low pressure continue threw the coming months capeverde systems will have a hard time making it all the way across and affecting the united states.Bermuda and areas like the azores would have to watch out.Basically the pattern is a deep trough slicing through the Atlantic near 29N x 60W with ULL's causing shear a dry conditions over parts of the atlantic.

But i would like to note as stated by weatherboykris the GFS model and the EURO model kinda halts all these trofs of low pressure and shows a strong ridge of the eastcaost of the united states in the coming days.Adrian

We will most definately see this statement by the nhc in the comings weeks more often which nothing out of the norm for this time of the year.

Tropical Weather Outlook
Nws Tpc/national Hurricane Center Miami Fl
530 Am Edt Sat Jun 23 2007

For The North Atlantic...caribbean Sea And The Gulf Of Mexico...

Tropical Cyclone Formation Is Not Expected During The Next 48 Hours.

Forecaster Mainelli
Member Since: Posts: Comments:
208. GainesvilleGator
11:46 AM GMT on June 23, 2007
Baha, you mean to tell me that you have to go way back to 1926 to find a Cape Verde hurricane in July? I wouldn't worry about the waves coming off of Africa four another 4 weeks. The water is still way too cold that far out.
Member Since: Posts: Comments:
207. BahaHurican
7:32 AM EDT on June 23, 2007
Morning, all.

I notice another fairly strong wave coming off W. Africa this morning. I agree with Adrian that the potential for survival across the ATL is small, but I am thinking also about the trends. The SW Car. system we were watching yesterday was based on one of the waves that made it across in a very disorganized fashion. This means the ITCZ has already begun shifting north, which is making me think Cape Verde type systems may start affecting us a little earlier this year.

Also these waves are looking quite powerful (remember 93L the other week?)which suggests that more of them may potentially survive the trek across the ATL once conditions become more conducive.

I do know that powerful Cape Verde hurricanes in July are not anomolous; aside from the 2005 season, one of the worst hurricanes to hit Nassau, Bahamas, was in late July 1926, and it formed from a W. African wave.
Member Since: Posts: Comments:
206. WPBHurricane05
6:57 AM EDT on June 23, 2007
Lets not forget what happened to the other African waves

Member Since: July 31, 2006 Posts: 56 Comments: 8112
205. WPBHurricane05
6:56 AM EDT on June 23, 2007
SAL=Saharan Air Layer

Basically African dust.
Member Since: July 31, 2006 Posts: 56 Comments: 8112
202. KoritheMan
9:56 AM GMT on June 23, 2007
And Adrian, the SAL is not actually that strong until you run into that huge pink mass. The SAL I would say is at best, moderate, except for the pink areas, where SAL is extreme.

I doubt the wave will even become an invest, but nevertheless, I'll watch it.
Member Since: Posts: Comments:
201. KoritheMan
9:55 AM GMT on June 23, 2007
If it can survive the SAL though, we need to monitor it. :)
Member Since: Posts: Comments:
200. hurricane23
8:32 AM GMT on June 23, 2007
I dont see to much potential with that wave of the african coast as the SAL is quite strong .
Member Since: Posts: Comments:
199. C2News
3:31 AM EDT on June 23, 2007
Story, impressive looking wave coming off of Africa, it looks like it has potential.
Member Since: July 17, 2006 Posts: 73 Comments: 622
198. StoryOfTheCane
6:46 AM GMT on June 23, 2007
Member Since: Posts: Comments:
197. C2News
1:17 AM EDT on June 23, 2007
True Boynton, I believe all activity should be monitored even if it is in-probable that a storm would form from something along those lines. It is a possibility that something like that could happen early in the season. Looking at past years, such as 2005, Arlene and Bret formed in the Carribean and BOC. But, statistically Cape Verde type storms don't form until August. People tend to focus more on points of interest in typical points of origin for that time in the season. Saying that, all systems should be monitored. If a weak low off Florida gets attention, then so should one coming off of Africa. There have been no instances in the new millenium where a storm came off of Africa to form. The farthest out was Ana, which formed near Bermuda in April of '03 I believe. I'm off to shop for backpacks, stay safe everyone.
Member Since: July 17, 2006 Posts: 73 Comments: 622
196. BoyntonBeach
4:53 AM GMT on June 23, 2007
C2News, plenty of people have been referencing the early rains off of Africa, and lately the change with the SAL directly off the coast. I realize it's early in the season, but all the blob watching has been in the Carib ! Is there a correlation to the activity here that we need to be concerned about ?
Member Since: Posts: Comments:
195. Alec
12:39 AM EDT on June 23, 2007
Yes you are right......

dry air at the surface is the level where it can really hurt storm formation.....cold and dry air aloft can really enhance severe weather...Night guys....
Member Since: Posts: Comments:
194. C2News
12:34 AM EDT on June 23, 2007
Boynton: Cape Verde and Africa originated waves are not looked at for potential until later in the season when they can survive the trek across the Atlantic. Late June origins occur off the east coast of the southeast, the Carribean, and the Gulf of Mexico. While a cape verde system is not impossible, it is statistically unlikely.
Member Since: July 17, 2006 Posts: 73 Comments: 622
193. Jedkins
4:30 AM GMT on June 23, 2007
Well all I know is it was supposed to be very unfavorable today and thats best thing I can think of as to why it wasn't so favorable sor strong storms.

Plus most of the time, dry and subsidence do inhibit strong storms a lot, but under certain conditions yes it can ehance the severe potential. I think I'm right on that I believe?
192. Jedkins
4:29 AM GMT on June 23, 2007
I do understand that, but I think we had warmer air aloft today as well.
191. Alec
12:17 AM EDT on June 23, 2007
Jed, dry air aloft can actually aid in severe weather potential.....can cause air to cool more rapidly, increasing wind and hail threats....read more here-link
Member Since: Posts: Comments:
190. Jedkins
4:11 AM GMT on June 23, 2007
Tampa had 2.85 from the same cluster of storms this evening, definitely good for Tampa too.
189. Jedkins
3:37 AM GMT on June 23, 2007
ya they were boarder line severe, the only reason they weren't is that conditions today were strongly against severe weather. Its amazing the amount of intense lightning under these conditions, dry air aloft usually means very little lightning, and it also means shallow convection. But these storm tonight were 40,000 footers and had incredible non stop lightning strikes.

I mean we get those kinds of storm here a lot. But not on a night of dry air and a weak subsidence inversion! lol
188. Tazmanian
8:58 PM PDT on June 22, 2007
Tropical Weather Outlook

Statement as of 10:30 PM EDT on June 22, 2007

For the North Atlantic...Caribbean Sea and the Gulf of Mexico...

A westward-moving tropical wave...with associated scattered shower
and thunderstorm activity...has moved over portions of Central

Tropical cyclone formation is not expected during the next 48 hours.

well that is the end of that have a good week end all
Member Since: Posts: Comments:
187. BoyntonBeach
3:59 AM GMT on June 23, 2007
Not 1 Cape Verde, Not 1 African wave, All the talk is about the Caribbean blobs ??? What are we in for this year ???
Member Since: Posts: Comments:
186. BoyntonBeach
3:50 AM GMT on June 23, 2007
Anybody ?

All that activity in the Caribbean is making me nervous....that's where Wilma formed (not referencing BH)
Member Since: Posts: Comments:
185. Jedkins
3:34 AM GMT on June 23, 2007
its good we got wacked tonight, because are classic soakers won't be back for about 3 or 4 days, then we should get into a deep tropical pattern.

My rain guage is at over 10 inches for the month now, thinga are a lot better. I hate to see we have drying coming, but the good news is its only for a period, and we have had enough rain to make it through so it won't get too dry
184. BoyntonBeach
3:36 AM GMT on June 23, 2007
Nice Jedkins ! As long as it's not too Extreme !
Member Since: Posts: Comments:
183. franck
3:33 AM GMT on June 23, 2007
Congrats Jedkins...we are like parched peanuts here in GA and AL.
Member Since: Posts: Comments:
182. BoyntonBeach
3:33 AM GMT on June 23, 2007
All that activity in the Caribbean is making me nervous....that's where Wilma formed (not referencing BH)
Member Since: Posts: Comments:
181. Jedkins
3:21 AM GMT on June 23, 2007
had intense sheets of rain and wind with non-stop thousands of lightning strikes here. We picked up about 2.00 inches here tonight, real good classic storms.

We actually got some brief street flooding here, since all that rain fell in about 30 min, but thats very typical around here this time of year.
180. TheCaneWhisperer
11:16 PM EDT on June 22, 2007
We have a little more time for that Boynton! The Bermuda high usually doesn't settle until early to mid-July. Models are saying further south and west but, just models! Once things settle down here in 2 to 3 weeks, I think we'll see a more south and west Bermuda High. The Ensemble 500 to 1000mb thickness shows this trend.
Member Since: Posts: Comments:
179. BoyntonBeach
3:15 AM GMT on June 23, 2007
Alright clwstmchasr ! Glad to hear it !

Cane, where do you think the Bermuda High will set up ???
Member Since: Posts: Comments:
178. TheCaneWhisperer
10:59 PM EDT on June 22, 2007
I am the doom and gloom guy with 20, well, now 22 with the honorable mentions. OK, Barry was legit, nonetheless, going to be an active year IMO. Things seem to be settling into place in the next couple weeks, get a better Idea! I will be giving my July outlook this weekend, which includes our first Hurricane! June was a bust with Barry so, let's see how we do this month.
Member Since: Posts: Comments:
177. BoyntonBeach
3:04 AM GMT on June 23, 2007
If it's going to rain I'm on it !!!
Member Since: Posts: Comments:
176. TheCaneWhisperer
10:58 PM EDT on June 22, 2007
Rain! Your Lucky. Dry as a bone here today and yesterday and the day before.
Member Since: Posts: Comments:

Viewing: 226 - 176

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18Blog Index

Top of Page

Dr. Jeff Masters' WunderBlog


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

Local Weather

46 °F

JeffMasters's Recent Photos

Afternoon clouds over Southwest Puerto Rico
Storm clouds gathering over Half Dome
Sierra snow
snowman at Yosemite Falls