Bahamas low slow to grow

By: Dr. Jeff Masters , 1:23 PM GMT on June 23, 2006

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A non-tropical low pressure system just northeast of the Bahama Islands now has a surface circulation, and is expected to slowly grow more organized as it moves west-northwest towards Florida over the next two days. A QuikScat satellite wind estimate from 6:38 am EDT this morning revealed winds of about 15 - 20 mph in most of the region, with one tiny spot of higher winds in an intense thunderstorm near 23N 72W. Wind shear over the disturbance has remained in the 10 - 25 knot range, which is keeping the deep thunderstorm activity to the east of the exposed circulation center. The wind shear is forecast to decrease by about 5 knots over the next day, which may allow thunderstorm activity to build in closer to the center. However, as one can see from the water vapor satellite image below, there is a large area of very dry air over Florida. This dry air is significantly inhibiting thunderstorms from building on the west side of the low. The dry air isn't going away, and the combination of the dry air and moderate wind shear will probably conspire to keep the low from becoming a full-fledged tropical depression. The low is forecast to move over Florida by Sunday, where it should bring welcome rains. A trough of low pressure swinging down from Canada should then pick up the low and move it northwards.


Figure 1. Latest water vapor satellite image shows a very dry airmass (brown colors) over Florida, extending eastward into the Bahamas. The area of clouds at the edge of this dry air is what we are watching.

Hurricane-resistant homes
An interesting article from the New York Times yesterday described new super-strong homes being built in Florida and on the Gulf Coast. Insurers love them, and are offering up to 25% discounts on policies. With the high levels of hurricane activity observed since 1995 expected to continue at least another 10-20 years, expect to see this trend continue. I'd certainly be in the market for one if I lived in Florida!

I'll be back with an update later today if there is a significant change in the Bahamas system. I'll save my discussion of the large-scale weather pattern over the Atlantic so far this June for later.

Jeff Masters

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141. Cavin Rawlins
4:35 PM GMT on June 23, 2006
SUBJ/TROPICAL CYCLONE FORMATION ALERT 231400Z JUN 06//
WTNT 21 KNGU 231500
RMKS/
1. FORMATION OF A SIGNIFICANT TROPICAL CYCLONE IS POSSIBLE WITHIN
100 NM EITHER SIDE OF A LINE FROM 26.3N 72.1W TO 28.0N 76.0W
WITHIN THE NEXT 12 TO 24 HOURS. AVAILABLE DATA DOES NOT JUSTIFY
ISSUANCE OF NUMBERED TROPICAL CYCLONE WARNINGS AT THIS TIME.
WINDS IN THE AREA ARE ESTIMATED TO BE 20 TO 20 KNOTS. METSAT IM­
AGERY AT 231200Z INDICATES THAT A CIRCULATION CENTER IS LOCATED
NEAR 27.0N 73.3W. THE SYSTEM IS QUASI-STATIONARY AT 00 KNOTS.
2. REMARKS:
3. THIS ALERT WILL BE REISSUED, UPGRADED TO WARNING OR CANCELLED BY 241500Z.
//
Member Since: July 24, 2005 Posts: 407 Comments: 19076
140. Cavin Rawlins
4:34 PM GMT on June 23, 2006
my new blog is up.....it discusses some websites of interest-stormjunkie.com and weathercore.com - and some bloggers of interest.

also you can leave comments about the question i posted today.
Member Since: July 24, 2005 Posts: 407 Comments: 19076
139. Cavin Rawlins
4:31 PM GMT on June 23, 2006
guys the Navy has issued a tropical formayion alert

http://www.nrlmry.navy.mil/tc-bin/tc_home2.cgi?YEAR=2006&MO=06&BASIN=ATL&STORM_NAME=91L.INVEST&PROD=track_vis&PHOT=yes&ARCHIVE=active&NAV=tc&AGE=Latest&STYLE=tables
Member Since: July 24, 2005 Posts: 407 Comments: 19076
138. tspree15
4:29 PM GMT on June 23, 2006
I'm no weather expert but very interested in tropical storms. Just wanted to say how much I enjoy reading all your posts and speculations.

Thanks!
137. NAtlanticCyclone
4:26 PM GMT on June 23, 2006
I admit that I was wrong about this wave becoming a depression by today at five, but I still will leave time for error as you always have to with the weather. Today around 11pm is probably the best time now to see or maybe tomorrow morning at 2 or 5 am now. Category one at landfall on the North Carolina coast. Early guess. Please stop by and read my blog. Any comments, feel free to write them down or just email me thank you.
136. Inyo
4:12 PM GMT on June 23, 2006
if you get tired of that little blob and want something else to talk about...

it looks like the north american monsoon will be starting this week around the desert Southwest. It usually forms around july 4th so it's a bit early this year. Hopefully this means rain in Arizona, etc.
Member Since: September 3, 2002 Posts: 42 Comments: 873
135. HurricaneKing
4:09 PM GMT on June 23, 2006
New blog
Member Since: July 6, 2005 Posts: 71 Comments: 2481
134. ProgressivePulse
4:08 PM GMT on June 23, 2006
All depends on when the trough picks it up, I think the nam is suggesting it will make the coast before it gets picked up.
Member Since: August 19, 2005 Posts: 5 Comments: 5405
133. PBG00
4:07 PM GMT on June 23, 2006
Not scared..just..interested..these storms tend to have a mind of their own the last two seasons. I like to have all the imput,if something does spin up it won't take long to make to my backyard. Thanks.
Member Since: October 20, 2005 Posts: 14 Comments: 6650
131. IKE
4:04 PM GMT on June 23, 2006
PBGOO...I wasn't trying to scare you...just reporting one computer model...the NAM isn't very reliable on location. It had Katrina from NW Florida to the upper Texas coast. I remember how it jumped around.

Sorry...didn't mean to frighten you.
Member Since: June 9, 2005 Posts: 23 Comments: 37858
129. ProgressivePulse
4:01 PM GMT on June 23, 2006
I think the high pressure above it will remain strong. Just a hunch till something develops and we see how it reacts to the conditions around it.
Member Since: August 19, 2005 Posts: 5 Comments: 5405
128. StormJunkie
4:01 PM GMT on June 23, 2006
My point is that the GFS, CMC, and Nogaps all show it going more North then S Fla.
Member Since: August 17, 2005 Posts: 26 Comments: 16586
127. PBG00
3:57 PM GMT on June 23, 2006
Perfect..The storm that was wasn't and now is...again..enlighten me..why the SE coast now?
Member Since: October 20, 2005 Posts: 14 Comments: 6650
126. KShurricane
3:54 PM GMT on June 23, 2006
The Colorado State page has some early model runs for the Bahama Blob. Right now its just the BAMS and they all take it into Northern Florida in about 60 hours. The intensity models make it a tropical storm. It will be interesting to see what the more reliable models say. I think we will have a TD by this time tomorrow and Beryl by late Sunday.
125. ProgressivePulse
3:53 PM GMT on June 23, 2006
Thank You SJ, I kind of agree with the latest NAM soloution also. I say kinda because there is no LLC yet. I say yet becuase I do think it will this evening.
Member Since: August 19, 2005 Posts: 5 Comments: 5405
124. IKE
3:50 PM GMT on June 23, 2006
The NAM does have crazy track adjustments...but even it has it going in at Florida's SE coast...

Here's a link... http://www.nco.ncep.noaa.gov/pmb/nwprod/analysis/carib/nam/12/model_s.shtml
Member Since: June 9, 2005 Posts: 23 Comments: 37858
123. rwdobson
3:49 PM GMT on June 23, 2006
i have a trip to FL scheduled for monday, so based on murphy's law i'd say a cat 3 heading for melbourne....

in reality, TD or maybe TS.
Member Since: June 12, 2002 Posts: 0 Comments: 1589
122. PBG00
3:49 PM GMT on June 23, 2006
Thanks SJ...I actually have been to your sight..was just bein lazy...Great site by the way
Member Since: October 20, 2005 Posts: 14 Comments: 6650
121. StormJunkie
3:48 PM GMT on June 23, 2006
PBG00

Find all the models and more at StormJunkie.com

It is all there and laid out so it is easy to find.

See ya
SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16586
120. StormJunkie
3:46 PM GMT on June 23, 2006
The nam is not a very reliable tropical forecast model, not to mention track is goign to be very tough to forecast by any model until we have that illusive llc.

SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16586
118. PBG00
3:45 PM GMT on June 23, 2006
gotta link for the nam?
Member Since: October 20, 2005 Posts: 14 Comments: 6650
117. PBG00
3:43 PM GMT on June 23, 2006
S Fla?
Member Since: October 20, 2005 Posts: 14 Comments: 6650
115. IKE
3:38 PM GMT on June 23, 2006
Latest NAM has it hitting south Florida as a TD/TS and then turning north paralleling the east Florida coast. I don't think it will turn north that abruptly...

New GFS is running....
Member Since: June 9, 2005 Posts: 23 Comments: 37858
114. rwdobson
3:38 PM GMT on June 23, 2006
guy...only two little quads? how do you figure? try searching for a specific city. i've seen melbourne, jacksonville, tallahassee, tampa, miami...looks like it has the whole state, or most of it.
Member Since: June 12, 2002 Posts: 0 Comments: 1589
113. rwdobson
3:34 PM GMT on June 23, 2006
this thing does have a better look...the dry air on one side is keeping it from getting too strong, but i wouldn't be surprised to see a TD. i think it will always have the "half storm" look that alberto had.
Member Since: June 12, 2002 Posts: 0 Comments: 1589
112. guygee
3:33 PM GMT on June 23, 2006
Hey rwdobson - I hung out to look for a reply like yours...check your own link and look at the area of coverage...two little quads in the whole state, virtually nothing, right?

What, if you were buying a house you wouldn't ckeck a topographic map to see if you were in a flood zone? Do you think Katrina would have held it's own/intensified over land if it had crossed the FL spine instead of extreme S. FL?
Want to know if you are at risk for storm surge on the FL Gulf coast? Need a good Topo map for that, right?

OK, see everyone later, fire away if you want...
Member Since: September 16, 2005 Posts: 0 Comments: 3167
111. lightning10
3:29 PM GMT on June 23, 2006
You know I read the article about the houses. They sound good but there is a problem I have with them. What if a lot of these are built and then we have a situation where a lot of people dont leave there house because they think there safe then a few hours before the storm makes landfall it becomes a lot stonger in a short period of time. Then we would have a bad situation where the death count would be higher then if people would have left.

Just something to keep in mind.
Member Since: November 24, 2005 Posts: 41 Comments: 630
110. HurricaneMyles
3:29 PM GMT on June 23, 2006
Shear, I asked about shear. Now I know that alot of the eastern side is being lopped off to the east. But in the center (I use that term loosly) and on the west side it is going up and then west. Cummon guys it is not a big ferocious CAT 5 but this is the stuff that needs more studying. Formation and intensity are the two things that the NHC will admit to knowing little about. So lets study it. I think scotts had a question about central pressure earlier. Anyone get that? Now is a time for exploring. You are all seeing the multiple vorticies phenomena. I think that the system first throws as much convection (energy) as it can into the air (using the multiple vorticies and then begins to wrap this energy around a central core. Obviously that is how it works you can read about that in a book. But really it seems to me that it is usually about 4 sub vortices. One in each quad? Now there is something to debate!

The minimum pressure of this thing is only attainable from a ship that makes it into the center, which is unlikely, or a recon plane, which wont happen until atleast TD Status.

As far as these voticies we see go, here's my take - Each of these votices is a low level circulation which has the possibily of becoming the storms main center. They form under the convection, but since shear is high and blowing clouds to the east they soon become exposed and start to die. They aren't strong enough to cause thunderstorms around them once exposed to shear and dry air so they simply spin out and die. You only see these in sheared systems when the clouds tops are continuosly being removed so that we can see down to the surface. And if a goof busrt of convection starts, like we saw in Alberto, a new llc will form under it. If conditions in the immediate area are good, then it will strengthen and ultimatly take over, but if llc keep forming under high shear, the clouds will be ripped apart and we will keep seeing exposed llc's spinning to thier death.

Now I could be wrong here, but these spinning voticies look remarkably like eyes in major hurricanes if you added the clouds around it. Which is why I think these are the week low level circulations that precede a strong eye. I've seen small, medium, and large varieties of these over the last couple of seasons, just like we see different size hurricane eyes. Again, I could be wrong, they just look remarkable similiar.
Member Since: January 12, 2006 Posts: 5 Comments: 827
107. IKE
3:25 PM GMT on June 23, 2006
Oops...MORE favorable Dr. M.....
Member Since: June 9, 2005 Posts: 23 Comments: 37858
106. ErikMia
3:23 PM GMT on June 23, 2006
000
ABNT20 KNHC 231519
TWOAT
TROPICAL WEATHER OUTLOOK
NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL
1130 AM EDT FRI JUN 23 2006

FOR THE NORTH ATLANTIC...CARIBBEAN SEA AND THE GULF OF MEXICO...

SATELLITE IMAGERY AND SURFACE OBSERVATIONS INDICATE THAT THE BROAD
AREA OF LOW PRESSURE CENTERED ABOUT 200 MILES EAST OF THE
NORTHWESTERN BAHAMAS HAS BECOME BETTER ORGANIZED THIS MORNING.
UPPER-LEVEL WINDS HAVE BECOME SOMEWHAT MORE FAVORABLE FOR
DEVELOPMENT...AND A TROPICAL OR SUBTROPICAL DEPRESSION COULD FORM
DURING THE NEXT DAY OR SO AS THE SYSTEM MOVES SLOWLY
WEST-NORTHWESTWARD. AN AIR FORCE RESERVE HURRICANE HUNTER AIRCRAFT
IS SCHEDULED TO INVESTIGATE THE SYSTEM ON SATURDAY...IF NECESSARY.

ELSEWHERE...TROPICAL STORM FORMATION IS NOT EXPECTED THROUGH
SATURDAY.

$$

FORECASTER BEVEN
105. Caffinehog
3:21 PM GMT on June 23, 2006
Whirlwind, Alberto was barely born. Considering how much the shear separated the center from the convection, I'm surprised that it was.
Alberto, and many of the storms last year, including the tropical wave that spawned Katrina, survived unprecedented amounts of shear. To ask the NHC to predict something that has never or rarely been seen before is asking too much.
Of course we now should ask them, "Why?" and we should expect them to look out for this in the future.
Member Since: June 5, 2003 Posts: 0 Comments: 40
104. StormJunkie
3:20 PM GMT on June 23, 2006
Right on 53rd.


I am out for a bit, but watch the 74N 26W area of convection, and again, good call on that ProgressivePulse.

StormJunkie.com-models, imagery, SSTs, storm video, and much more.

I'll be back latter ya'll
SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16586
103. rwdobson
3:17 PM GMT on June 23, 2006
florida map with topo contours? lol isn't the highest point in the state 350 ft above sea level?

but terra server does have usgs topo maps on line, if you want em...

Link
Member Since: June 12, 2002 Posts: 0 Comments: 1589
102. whirlwind
3:14 PM GMT on June 23, 2006
(watching the World Cup)
101. Cavin Rawlins
3:13 PM GMT on June 23, 2006
my new blog is up!
Member Since: July 24, 2005 Posts: 407 Comments: 19076
100. code1
3:12 PM GMT on June 23, 2006
Hi longtimers and newbies this year. Have any of you longtimers really looked to see who was the, ummmm, let's just say different mindset bloggers, this year? They can't help it, haven't been here long enough. Next year, they will talk the talk, and walk the walk. Have a great weekend all. Pray for rain for us that need it and enjoy no real tropical formations for God's sake! That brings up another point, seems to me the ones wishcasting here have never been through any of it except through the news or online. Funny at times!
Member Since: September 18, 2005 Posts: 66 Comments: 13872
99. 53rdWeatherRECON
3:11 PM GMT on June 23, 2006
Shear, I asked about shear. Now I know that alot of the eastern side is being lopped off to the east. But in the center (I use that term loosly) and on the west side it is going up and then west. Cummon guys it is not a big ferocious CAT 5 but this is the stuff that needs more studying. Formation and intensity are the two things that the NHC will admit to knowing little about. So lets study it. I think scotts had a question about central pressure earlier. Anyone get that? Now is a time for exploring. You are all seeing the multiple vorticies phenomena. I think that the system first throws as much convection (energy) as it can into the air (using the multiple vorticies and then begins to wrap this energy around a central core. Obviously that is how it works you can read about that in a book. But really it seems to me that it is usually about 4 sub vortices. One in each quad? Now there is something to debate!
Member Since: August 5, 2005 Posts: 2 Comments: 80
98. guygee
3:11 PM GMT on June 23, 2006
Personally, I think NOAA and all it's branches (NWS, NHC, CPC, HPC) are a great national resource and deserve more funding, instead of taking all the cuts they have been getting, not to mention the censoring (NWS employees are being denied their scientific duty to present papers at scientific conferences, and are being fired if they defy the orders from above).

Look at the USGS...used to be a great national resource...now they have been virtually privatized...just try to find a good statewide Florida topo map with contours for free online...any luck? Why Not? All that information was gathered at the taxpayer's expense, but now we have to pay again to get access, because the politicians decided to axe much of the funding for this formerly great and useful agency...

I'll check in with everybody here later...going to take some time under the big sky in the fresh air.
Member Since: September 16, 2005 Posts: 0 Comments: 3167
97. rwdobson
3:11 PM GMT on June 23, 2006
on tammy, maybe the night shift was short a few people..or they were totally burned out by the time the t storm rolled around...or they were playing texas hold em on line...
Member Since: June 12, 2002 Posts: 0 Comments: 1589
96. StormJunkie
3:09 PM GMT on June 23, 2006
The models really are becoming insistant on two systems aren't they sayhuh

Member Since: August 17, 2005 Posts: 26 Comments: 16586
95. StormJunkie
3:07 PM GMT on June 23, 2006
StromTop your methodology is flawed and everyone here sees it, so give it a rest. Be subjective, because otherwise you will be wrong 90% of the time and right 10%. No credability with me even after your decent analysis of Katrina.

SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16586
94. sayhuh
3:07 PM GMT on June 23, 2006
Let me revise my thoughts. I take back the fact that I think the low will shift SE. I think the Bahama blob will move onshore as a TD at best, and will move up the front coming over the central US causing quite the rain maker on the coast. I think the SE component I first saw will become its own storm..I like it as a TS. It is the convection currently NE of PR. I am still thinking June 30-July 2nd for this one to be named. I am following in part the GFS/CMC 850 vort outputs. I think it will take a bit longer to develop than the models.
93. StormJunkie
3:05 PM GMT on June 23, 2006
Yea Dob, Rand will get you every now and then. He is a hair off the cuff sometimes.

:o)

SJ
Member Since: August 17, 2005 Posts: 26 Comments: 16586
91. STORMTOP
3:05 PM GMT on June 23, 2006
you people need to calm down in here...nothing is going to develop until after the 4th of july...the only thing i see develpoing in here is the tempers from you guys...go relax spend time with your family i can assure you nothing at all will develop from this system except a little rain which you get there all the time..so quit worrying and go do something constructive like i did yesterday went out and turned crawfish red from the sun...i am so sore this morning im going soak in some vinegar...you guys need to calm down..53rd nothing will come of this and im afraid you all will be disappointed when DR GRAY comes out with his new forecast...14 STORMS AND THATS STRETCHING IT BELIEVE ME IT IS...QUIT LOOKING AT THE DAM COMPUTERS YOU WILL BE BETTER OFF...THEY ARE GARBAGE...StormTop

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

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