Tropical Storm Bret forms near the northern Bahamas

By: Dr. Jeff Masters , 2:57 PM GMT on July 18, 2011

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Tropical Storm Bret formed last night over the Northwestern Bahama Islands, and is expected to bring heavy rains of 2 - 4 inches to the northernmost Bahama Islands today and Tuesday, as the storm drifts slowly to the north-northeast. Bret's formation date of July 17 is two weeks ahead of the usual formation date for the Atlantic's second storm of the season, which is August 1. The latest data from the Hurricane Hunters, taken between 4 - 5am EDT, showed a 100-mile wide area of tropical storm-force winds in excess of 39 mph affecting only the northernmost Bahama Islands--the Abacos. A personal weather station on Great Abaco Island recorded a wind gust of 48 mph at 12:23 am today. Satellite imagery shows that Bret has not improved in organization this morning, thanks to dry air to the northwest that has been blown into the storm's core by upper-level northwesterly winds. long-range radar out of Melbourne, Florida shows that Bret is currently dumping very little rain over the Bahamas, and one thin rain band from the storm is affecting the Florida East Coast with rainfall amounts less than a quarter inch. Wind shear is a moderate 10 - 15 knots, and sea surface temperatures are 28 - 29°C, which is 2°C above the 26.5°C threshold needed to support a tropical storm.


Figure 1. Morning satellite image of Tropical Storm Bret.

Forecast for Bret
None of the models develop Bret into a hurricane. though the GFDL model has it coming close. Given the current ragged appearance of the storm, plus the forecast by the SHIPS model that wind shear will rise to the high range, 20 - 25 knots, by Tuesday morning, it is unlikely Bret will become a hurricane. NHC is giving Bret a 22% chance of developing into a hurricane by Tuesday.

Steering currents are weak off the coast of Florida, and Bret can be expected to move slowly near 5 mph through Tuesday, before the storm gets caught in a trough of low pressure and lifted northeastwards out to sea. It currently appears that the only land areas that will be affected by Bret will be the northernmost Bahama Islands, today and Tuesday.

None of the reliable models predict tropical cyclone development over the remainder of the Atlantic through July 25.


Figure 2. Visible satellite image of Typhoon Ma-on from NASA's Aqua satellite taken July 18, 2011. Image credit: NASA.

Weakened Typhoon Ma-on headed towards Japan
Typhoon Ma-on has weakened to a large Category 1 storm as it heads towards Japan, and is expected to brush the east coast of the main island of Honshu on Tuesday. The typhoon weakened over the past day, thanks to an eyewall replacement cycle where the inner eyewall collapsed, and a new, larger eyewall formed from an outer spiral band. Ma-on was expected to intensify once this process completed, but the eyewall replacement process significantly disrupted the storm, and it is unlikely Ma-on will be able to recover. This is good news for Japan, since Ma-on is a huge storm with tropical-storm force winds that extend 225 miles north of the center.

Jeff Masters

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Be back later...
It appears from latest satellite Estimates Brets Weakening....
Bret T# 2.7
Weakening Flag : ON
Though they did just find Raw 3.2....
Final T# Adj T# Raw T#
2.6 2.9 3.2


Well time to move on i guess
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Quoting Patrap:
..The Rescue Rain is en route, Houston

Do you copy?




I'm mowing the grass and cussing, but I'll gladly take some more. We've actually had some nice rainy weather the last week. The grass was lying in wait.
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Quoting aspectre:
The NHC should quit assuming that the public is composed of total morons, etc. etc. etc.

When they visit the storm with reconnaissance aircraft, all they can do is measure winds at certain locations and certain times. No one knows with certainty what the actual maximum wind speed is at any given time, nor does that really matter if the approximation given by estimates are close enough. I could drone on and on.
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Member Since: July 3, 2005 Posts: 414 Comments: 125613
Thank you Patrap!!!
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Area forecast discussion
National Weather Service New Orleans la
438 am CDT Monday Jul 18 2011


Short term...
moisture axis is obvious this morning and soundings continue to
support a deep moist environment. Precipitable waters remain above 2.25" until
Tuesday when they drop back under 2". Light boundary layer wind
speeds...low convective temperatures and low local levels make this another
day that waterspouts can be produced. Most of these will remain
over open water...but the potential...as usual...will be that one
or two could make a brief visit onshore. Mariners and individuals
should watch for waterspouts and avoid them. Isolated rainfall
amounts are expected to be heavy again today and will range
between 3 to 5 inches. The main areas to be affected should from
coastal Mississippi back through southeast la around and south of
Lake Pontchartrain. Areas of rain will begin to move away from
coastal miss after noon today. Ridge will do its best to build
into the southeast Continental U.S. Through middle week and affect US by warming things
up and clearing US out for the most part. Some moistures comes
back toward the end of the week though.
Member Since: July 3, 2005 Posts: 414 Comments: 125613
The Nogaps is making EPAC storms again... hinting at another at the end of the run. it needs to be renamed the.....

N~ New
O~ On
G~ Generating
A~ Anti
P~ Pacific
S~ Storms

This means its new at trying to create atlantic storms, and it still favors the pacific more...

if you have a better concept let me know...
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I see that Tropical Storm Bret finally has been making the northward drift that was anticipated by the NHC and the computer models.
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..The Rescue Rain is en route, Houston

Do you copy?



Member Since: July 3, 2005 Posts: 414 Comments: 125613
Does anyone think the storms over Southern Louisiana will turn into anything?
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68. 7544
looks like according to some models by the time bret moves away we should have someting new to watch in the catl
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Quoting aspectre:
But then they can't even stop SHOUTing for attention, not even when nothing merits such manic behaviour.
Studies have shown that most-approaching-all people have difficulty reading allCAPs printing beyond a short word or phrase. And have even less comprehension of longer allCAPs writings.
If the idea is to serve the public, they should make things easy for the public. And save the SHOUT for emphasis about dangerous situation.

Well, they're not really shouting as internet users know it. See Question 14 here:

"Q14. Why are NWS text products typed in ALL CAPITAL LETTERS?
A14. It is not because we want to scream at you! This practice goes back many, many years and relates to international requirements for message dissemination. Some of our international partners still use low-tech dissemination technology which requires the continued use of ALL CAPS. Since the U.S. is an international member of the World Meteorological Organization (WMO), we follow those guidelines that still exist for the benefit of all nations. That is why TAFs, AIREPs, Marine Forecasts, etc. are typed in ALL CAPS. "
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#44
I'll add an amen on that, Pat...
A few weeks ago, I would have bet drought relief would come bearing a name for us... and it might yet to complete the exceptional drought to flood transition!

But yeah, climo still rules... July is the wettest month of year for SE LA - 7.85" average here - and this month is the 1st of year to finally have a surplus... Already had from 5-10" over my local area before this morning's event... And to consider had reached over an 18" deficit early June - that's huge for the wettest region of the wettest state of the lower 48...

BTW -
I'm doing my best to fan the rain your way, Texans!
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Quoting aspectre:
The NHC should quit assuming that the public is composed of total morons, and release the actual measured Max.Sus.Wind, the actual averaged speed of storm-center movement between two reports, and the center's actual heading averaged between two reports.

But then they can't even stop SHOUTing for attention, not even when nothing merits such manic behaviour.

BTW -- Studies have shown that most-approaching-all people have difficulty reading allCAPs printing beyond a short word or phrase. And have even less comprehension of allCAPs writings.
If the idea is to serve the public, they should make things easy for the public. And save the SHOUT for emphasis about dangerous situation.


One of the reasons for "all caps" is that these reports go out over standard military message format. That format has no provision for lower case letters. All caps is the standard and is not "shouting" as you call it. It has been that way for more years than you have probably been around.
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64. Skyepony (Mod)
Quoting muddertracker:


It doesn't think the shortwave trough will be enough to push it out?


Perhaps..it is a dynamical model so it's taking current conditions into account.
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I don't really see any vorticity at the 850 mb level with the wave around 30W as I trend it back. Just seems like it's ITCZ vort (not really moving westward).

Anyone else tried that and looked at the vort progression in that area?
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Quoting Skyepony:
Kinda interesting the model that has done the best overall with Bret, the GFDN, with an average of 6.7nm error lands this on the border of North & South Carolina.



It doesn't think the shortwave trough will be enough to push it out?
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so the best the satellite have, are 45 mph 1004 MB.. hmmmm the newest raw measurement is 3.2......
Interesting..........

Thanks canesfan
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Is there any potiential for developement of the wave that juat came off of Africa?
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57. Skyepony (Mod)
Kinda interesting the model that has done the best overall with Bret, the GFDN, with an average of 6.7nm error lands this on the border of North & South Carolina.

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Quoting HurricaneDean07:
Does Anyone have the latest Satellite estimates from Bret?
Link
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Does Anyone see Bret making a break north
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Quoting HurricaneDean07:
Does Anyone have the latest Satellite estimates from Bret?


UW - CIMSS
ADVANCED DVORAK TECHNIQUE
ADT-Version 8.1.3
Tropical Cyclone Intensity Algorithm

----- Current Analysis -----
Date : 18 JUL 2011 Time : 144500 UTC
Lat : 27:40:47 N Lon : 77:18:47 W


CI# /Pressure/ Vmax
2.7 /1004.6mb/ 39.0kt


Final T# Adj T# Raw T#
2.6 2.9 3.2

Center Temp : -50.7C Cloud Region Temp : -39.1C

Scene Type : CURVED BAND with 0.62 ARC in LT GRAY

Positioning Method : FORECAST INTERPOLATION

Ocean Basin : ATLANTIC
Dvorak CI > MSLP Conversion Used : ATLANTIC

Tno/CI Rules : Constraint Limits : 0.5T/hour
Weakening Flag : ON
Rapid Dissipation Flag : OFF

C/K/Z MSLP Estimate Inputs :
- Average 34 knot radii : 41km
- Environmental MSLP : 1017mb

Satellite Viewing Angle : 32.4 degrees

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The NHC should quit assuming that the public is composed of total morons, and release the actual measured Max.Sus.Wind and the actual averaged speed of storm-center movement between two consecutive reports instead of rounding to the nearest 5knots or 5mph.
They should also translate distances into kilometres and speeds into k/h. Typing data containing all 3 measurement systems ain't that hard, and most of the world would find it highly useful.

Plus they should release the center's actual heading averaged between two consecutive reports.
And it's rather amazing that HurricaneHunters routinely report center positions to a thousandth of a degree (0.06 nautical mile), yet the NHC releases only down to a tenth (6 nautical miles) even after excusing themselves beforehand for half-degree(30 nautical mile)errors.
Yes there are difficulties some times in locating the center, but those some times aren't nearly most of the time.

But then they can't stop SHOUTing for attention, not even when nothing merits such manic behaviour.
Studies have shown that most-approaching-all people have difficulty reading allCAPs printing beyond a short word or phrase. And have far less comprehension of longer allCAPs writings.
If the idea is to serve the public, they should make things easy for the public. And save the SHOUT for emphasis about truly dangerous situation.
Member Since: August 21, 2007 Posts: 0 Comments: 4860
Does Anyone have the latest Satellite estimates from Bret?
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with the outliar removed the actual averages are
1.74 Named Storms
0.47 Hurricanes
0.14 Major Hurricanes
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wonder how this ENSO season will shape up. any patterns like 2005? Strange how these troughs keep swinging down like last year
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Alright im going to do another experiment with this and take out 2005(the outliar) and be able to actually know the real average.
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Alright so as of since the active period began(1995)
We have had 2.0625 Named storms by this date in time.

Hurricanes: .625 by this date
Major Hurricanes: .25 by this date

So the Average since the active period began for this date is:
2 Named Storms
1 Hurricane
0 Major Hurricanes

Currently for 2011:
2 Named Storms
no Hurricanes...

Though this means were are slightly behind hurricane wise, there is still 4 months to go...
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Quoting DocNDswamp:
Good morning Patrap,

Our non-tropical low arrived on schedule!
Extremely hvy widespread rainfall this morn down here in N Terrebonne as we continue under flash flood warning - had to go read / dump my cheapo gauges as nearing 5" mark a few minutes ago... while my Cocorahs gauge will prolly be not far off, appears close to halfway up the outer tube!

I think it's safe to say the drought over SE LA has been alleviated... Turn the taps off, please, lol...

I do hope some of this makes it to SE TX by tomorrow...




Aiiii-eeeee, neighbor,


Yeah, good to see yas Doc,

Ma Nature sometimes favors the climatology fo sho.

And Ill take the Lows from the East on Land, anytime over dem ones dat come in from the S or Se anyday.

Member Since: July 3, 2005 Posts: 414 Comments: 125613
Good morning Patrap,

Our non-tropical low arrived on schedule!
Extremely hvy widespread rainfall this morn down here in N Terrebonne as we continue under flash flood warning - had to go read / dump my cheapo gauges as nearing 5" mark a few minutes ago... while my Cocorahs gauge will prolly be not far off, appears close to halfway up the outer tube!

I think it's safe to say the drought over SE LA has been alleviated... Turn the taps off, please, lol...

I do hope some of this makes it to SE TX by tomorrow...

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This date in history for the Tropics:
2006: TS Beryl Formed
2008: TS Cristobal Formed
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Quoting FLdewey:
Surf is picking up along the Brevard coast this morning...

Sweet! Break out the boogie boards and popcicles, may get another .25 inches there!
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What does 93.5 knots equal to in mph in a TC?..I thought it was 107 miles? Isnt the formula to multiply it by the knots by 1.15?
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http://www.ndbc.noaa.gov/show_plot.php?station=4101 0&meas=pres&uom=E&time_diff=-4&time_label=EDT


Pressures definitely not moving with normal diurnal swings.
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Quoting Darren23:
I'm a little confused here. The NHC released a Request for Comments thing for the SSHWS. Does this mean all hurricanes at 115kts will now be 130 mph storms instead of 135 mph storms?


It would if the NHC decides to adopt the standard. The NHC operates in kts and translates to MPH for the public's benefit. 110kts, a top-level cat 3 system, is 126.6MPH, which is rounded to 125MPH. 115kts, a bottom-level cat 4 system, is 132.3MPH, which should round to 130MPH but this would correspond to a category 3 system so instead they round it up to 135MPH. This is why you never see 130MPH systems in an advisory; that mile marker is lost in translation so to speak.

The slight correction of 1kt allows the NHC to start properly rounding the winds down to 130MPH and still classify it properly as a cat 4 storm. Ironically, this just means that now there would be no 135MPH systems as the next increment, 120kts, corresponds to 138.1MPH and would round up to 140MPH. This means now 135MPH would be the number lost in translation instead.
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I must be near the Center of the Low over NOLA,as the low scud dark ceiling is racing due west at round 25mph.
Member Since: July 3, 2005 Posts: 414 Comments: 125613
Bret forgot to eat his spinach last night :)
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Member Since: July 3, 2005 Posts: 414 Comments: 125613
However, the slight difference at that wind speed is rather insignificant.
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Quoting HurricaneDean07:
Thanks Nigel, havent seen the SST's lately...
Usually take care of posting the sst maps during the offseason, but get caught up watching the tropics more often... so for the most part 2011 has the upperhand on 2010, sst and # wise at this point in time.
It's amazing how quickly these SST's can change
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About JeffMasters

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