Colin ready to re-form; TSR keeps their Atlantic hurricane forecast numbers high

By: Dr. Jeff Masters , 1:54 PM GMT on August 05, 2010

Share this Blog
3
+

The remains of Tropical Storm Colin continue to generate heavy thunderstorm activity over the waters a few hundred miles northeast of Puerto Rico. Colin's remains are in a rather unfavorable environment for re-development, since the storm is passing beneath an upper-level low pressure system with dry air and high wind shear. Despite the high wind shear of 20 - 25 knots, Colin's remains have grown more organized during the past day, and a low-level circulation has formed. A pass of the Windsat satellite last night revealed that ex-Colin is already generating tropical storm force winds of 40 mph in isolated regions. Recent satellite imagery shows that heavy thunderstorm activity has increased in intensity and areal coverage this morning, and a low level circulation that may or may not persist has formed near 23.5N 65.5W (Figure 1.)

Forecast for Colin
The latest SHIPS model forecast predicts that wind shear will drop from 15 - 25 knots today to a moderate 10 - 20 knots on Friday. This relaxation of shear prompts most of the major models to predict re-development of Colin sometime in the next three days. NHC is giving Colin's remain a 50% chance of developing into a tropical depression by Saturday morning. A major trough of low pressure will move off the U.S. East Coast on Friday, and this trough will pull Colin to the north and cause it to slow down. All of the major forecast models are predicting that the trough of low pressure will be strong enough to fully recurve Colin out to sea early next week. Colin's remains may pass close to Bermuda on Saturday, with the latest 06Z (2am EDT) run of the GFDL model predicting that Bermuda will experience tropical storm force winds on Saturday as Colin passes to the west of the island. The Hurricane Hunters are scheduled to investigate Colin's remains at 2 pm EDT this afternoon. It currently appears that Colin will only be a threat to Bermuda and Newfoundland.


Figure 1. Morning satellite image of Colin's remains show a low-level circulation, exposed to view, has formed at the edge of a region of heavy thunderstorms.

92L
A tropical wave (Invest 92) a few hundred miles south of Jamaica is moving west at 15 - 20 mph. This wave is over warm water and is experiencing low wind shear of 5 - 10 knots, and could show some development over the next two days. However, the wave's rapid westward motion should bring it ashore over Nicaragua and Honduras on Friday and the Yucatan Peninsula on Saturday, and 92L probably does not have enough time over water to develop into a tropical depression. NHC is giving a 10% chance of this disturbance developing into a tropical depression by Friday morning.

Elsewhere in the tropics
The GFS model is predicting that a tropical wave that moved off the coast of Africa yesterday will develop into a tropical depression early next week. None of the other models is showing any obvious tropical cyclone development over the coming week. The current phase of the Madden-Julian Oscillation (MJO) over the Atlantic favors upward motion and enhanced probabilities of tropical storm formation, so it would not be a surprise to see a new tropical depression form next week between Africa and the Lesser Antilles Islands.

TSR keeps their forecast numbers for the coming hurricane season high
The British private forecasting firm Tropical Storm Risk, Inc. (TSR) joins CSU in calling for a very busy Atlantic hurricane season. The latest TSR forecast issued August 4 calls for 17.8 named storms, 9.7 hurricanes, 4.5 intense hurricanes, and an Accumulated Cyclone Energy (ACE) 183% of average (assuming an ACE of 101 is average.) These storm numbers are a slight drop from their July 6 forecast of 19.1 named storms, 10.4 hurricanes, and 4.8 intense hurricanes, but this is still a very aggressive forecast. The 50-year average is 10 named storms, 6 hurricanes, and 2 intense hurricanes. TSR predicts a 96% chance that this season will have an above-average ACE index, and only 4% chance it will be near normal. TSR rates their skill level for August forecasts as 51% above chance at forecasting the number of named storms, 64% skill for hurricanes, and 47% skill for intense hurricanes.

TSR projects that 5.7 named storms will hit the U.S., with 2.6 of these being hurricanes. The averages from the 1950-2008 climatology are 3.2 named storms and 1.5 hurricanes. TSR's skill in making these August forecasts for U.S. landfalls is 19% - 23% above chance. They give an 89% chance that the U.S. landfalling ACE index will be above average. In the Lesser Antilles Islands of the Caribbean, TSR projects 1.8 named storms, 0.8 of these being hurricanes. Climatology is 1.1 named storms and 0.5 hurricanes.

TSR cites two main factors for keeping their numbers high: below-average trade winds and near-record warm sea surface temperatures in the tropical Atlantic. TSR expects trade winds in the Main Development Region (MDR) for hurricanes over the Atlantic (the region between 10° - 20° N from Central America to Africa, including all of the Caribbean) to be 1.53 meters per second (about 3.4 mph) slower than average in this region, which would create more spin for developing storms, and allow the oceans to heat up, due to decreased mixing of cold water from the depths and reduced evaporational cooling.

Forecast numbers for the coming hurricane season
Here are the number of Atlantic named storms, hurricanes, and intense hurricanes predicted by the various forecast groups in their late May or early June forecasts:

23 named storms: PSU statistical model
20 named storms: UKMET GloSea dynamical model
18.5 named storms, 11 hurricanes, 5 major hurricanes: NOAA hybrid statistical/dynamical model technique
18 named storms, 10 hurricanes, 5 intense hurricanes: CSU statistical model (Phil Klotzbach/Bill Gray)
17.7 named storms, 9.5 hurricanes, 4.4 intense hurricanes: Tropical Storm Risk (TSR), hybrid statistical/dynamical model technique
17 named storms, 10 hurricanes: FSU COAPS dynamical model
10 named storms, 6 hurricanes, 2 intense hurricanes: climatology

And here are the new late July/early August forecast numbers so far:

15 named storms, 8 hurricanes: FSU COAPS dynamical model (July 15 forecast)
18 named storms, 10 hurricanes, 5 intense hurricanes: CSU statistical model (Phil Klotzbach/Bill Gray)
17.8 named storms, 9.7 hurricanes, 4.5 intense hurricanes: Tropical Storm Risk (TSR), hybrid statistical/dynamical model technique (Note: TSR had higher numbers of 19.1, 10.4, and 4.8 in their July 6 forecast)

This season has had three named storms so far (Alex, Bonnie, and Colin.) It will be difficult to have a season with 19 or more named storms, since the four seasons that had at least 19 named storms all had at least five named storms by this point (August 4.) These four seasons were 1887, 1933, 1995, and 2005.

Next update
I'll have an update on Friday morning.

Jeff Masters

Reader Comments

Comments will take a few seconds to appear.

Post Your Comments

Please sign in to post comments.

or Join

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: 1074 - 1024

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55Blog Index

1074. Drakoen
Microwave at the beginning of Colin's recent convective development shows the circulation clear as day with evidence of low level spiral bands on the southern side of the system.

Member Since: October 28, 2006 Posts: 57 Comments: 29905
Quoting sammywammybamy:
F5.F5.F5.F5.F5.F5.F5.F5... Fingers Getting Tired.. MUST NOT STOP


Lol -i'm quickly flicking between the NHC site and these:

http://weather.noaa.gov/pub/data/raw/ur/urnt12.knhc..txt

http://weather.noaa.gov/pub/data/raw/ur/urnt15.knhc..txt

all 3 are getting the F5 treatment
Member Since: Posts: Comments:
1071. angiest
Quoting sammywammybamy:


?


This may be a case of being separated by a common language...
Member Since: August 26, 2006 Posts: 16 Comments: 4766
Joe Bastardi HATES NOAA and it's obvious. ;)
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting ShenValleyFlyFish:


Believe it or not Bermuda is perfectly capable of looking out for itself


Lovely island; I've visited twice. But meteorologically speaking, they can't be truly autonomous until they send up their own weather satellites and stop using the U.S. ones... ;-)
Member Since: Posts: Comments:
Quoting EyewallCycle:
Se's back, official word.


Source?
Member Since: Posts: Comments:
Quoting Drakoen:
Colin's ACE wasting away.


Colin's been a TS for quite some time to me. Since yesterday evening.
Member Since: July 8, 2005 Posts: 259 Comments: 23590
Quoting srada:
All I will say bless those who do get hit with a storm this year and lose power especially with this heat wave..It will be horrible for anyone trying to clean up and live in
heat indexes well over 100 degrees..


It's miserable, we did it for Katrina until we got our generator. 3 hours after purchasing it our power came back on. A lifesaver for the 10 days we were without power for Gustav.
Member Since: Posts: Comments:
Quoting FLdewey:
God help the NHC email server if it's not Colin again LOL.


Thats what the NHC are doing - installing a new Email server that can cope with 3000 Wunderbloggers that are peed at them.
Member Since: Posts: Comments:
Colin is doing extremely well, considering he is under 20-30 kts. of Wind Shear.

Member Since: April 1, 2010 Posts: 9 Comments: 2699
1060. Drakoen
Colin's ACE wasting away.
Member Since: October 28, 2006 Posts: 57 Comments: 29905
1057. viman
Only if there updating, otherwise nutting til 800pm.
Member Since: Posts: Comments:
HDOB message hasn't come out in 22 minutes.
Member Since: July 8, 2005 Posts: 259 Comments: 23590
1055. Ron5244
Quoting IpswichWeatherCenter:


Well he is a useless meteologist - any chance of a link for the lolz?

The video is part of an Accuweather article. Enjoy it!
Angry Bastardi
Member Since: Posts: Comments:
Quoting Snowlover123:


That's your opinion. Could you have predicted for the Mid Atlantic to have a snowy cold year in July? I don't think so. Could you have predicted Humberto of 2007 to strike as a hurricane THREE DAYS before it actually formed? Could you have predicted Rita of '05, to hit Texas instead of New Orleans, like the NHC was hyping about?

So before you call anyone names, look at who you're dealing with first.


Sorry, but I just don't like the way he is full of himself.

However back with flossie in the EPAC i predicted her rapid intensification into a Cat 3 correctly.
Member Since: Posts: Comments:
Quoting rmbjoe1954:


They are probably going to call Colin a TS again-just waiting for all the data to support it.
Believe me. There is PLENTY of data to support that we have a TS.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Quoting sammywammybamy:


I know that. Did you think i was that dumb....


No. But why did u put it there?
Member Since: April 1, 2010 Posts: 9 Comments: 2699
Quoting IpswichWeatherCenter:
I wonder whats going on at the NHC - they normally start posting advisorys etc etc now.


They are probably going to call Colin a TS again-just waiting for all the data to support it.
Member Since: Posts: Comments:
1048. angiest
Quoting IpswichWeatherCenter:
I wonder whats going on at the NHC - they normally start posting advisorys etc etc now.


Sometimes they are a little late when there is a major update with data that arrived in the last hour, especially the last half hour.
Member Since: August 26, 2006 Posts: 16 Comments: 4766
Quoting IpswichWeatherCenter:


Well he is a useless meteologist - any chance of a link for the lolz?


That's your opinion. Could you have predicted for the Mid Atlantic to have a snowy cold year in July? I don't think so. Could you have predicted Humberto of 2007 to strike as a hurricane THREE DAYS before it actually formed? Could you have predicted Rita of '05, to hit Texas instead of New Orleans, like the NHC was hyping about?

So before you call anyone names, look at who you're dealing with first.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
I wonder whats going on at the NHC - they normally start posting advisorys etc etc now.
Member Since: Posts: Comments:
Quoting IKE:


Agree. I've read on here how well their buildings and houses are constructed.

And I've read their forecast.
Wasn't picking on you in particular. Yours was the easiest to quote that mentioned Bermuda as a concern.
Member Since: Posts: Comments:
Quoting IpswichWeatherCenter:
Recon hasn't reported for some time - am I right to be worried?


They might be typing out a Vortex message, coordinating with the NHC, NHC writing up the advisory, ect because Colin does have a closed LLC, loads of WSW - W winds that shifted to NE when they passed through the center.
Member Since: July 8, 2005 Posts: 259 Comments: 23590
Quoting Drakoen:


That is possible. Sometime they will say: the RECON was unable to provide a vortex message however conditions...there is still a high...
Oh ok.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Quoting Ron5244:
Hmmm, Bastardi seems a bit on the angry side in his latest video.


Well he is a useless meteologist - any chance of a link for the lolz?
Member Since: Posts: Comments:
Quoting sammywammybamy:


sammy, that's the same exact graph from 2:00.
Member Since: April 1, 2010 Posts: 9 Comments: 2699
1039. Levi32
Quoting StormW:


Hey Shen, good to see you!

Hey Levi!


Hey Storm!
Member Since: Posts: Comments:
1038. angiest
Quoting Seflhurricane:
Clouds, showers, and the slight chance of thunder, will arrive from the south tonight, ahead of TS Colin, which has strengthened and re-developed. Colin is a threat to Bermuda. Winds and showers will increase overnight Friday with Tropical Storm conditions expected Saturday. TS Colin is expected to pass to our west late Saturday, with conditions easing through Sunday. Please check often for updates.

this is from the bermuda weather service


I'm sure they are privy to information from the NHC before it is made public. ;) But they didn't issue a watch or warning?
Member Since: August 26, 2006 Posts: 16 Comments: 4766
1037. Ron5244
Hmmm, Bastardi seems a bit on the angry side in his latest video.
Member Since: Posts: Comments:
Quoting StormW:


Hey Shen, good to see you!

Hey Levi!


Back at you. Welcome aboard.
Member Since: Posts: Comments:
1035. Drakoen
Quoting MiamiHurricanes09:
I think that if there is no vortex message, they will not issue an advisory.


That is possible. Sometime they will say: the RECON was unable to provide a vortex message however conditions...there is still a high...
Member Since: October 28, 2006 Posts: 57 Comments: 29905
Quoting CybrTeddy:
HDOB hasn't come out in 14 minutes, so I think they're typing up a Vortex message.
Actually 22 minutes.

202600 2430N 06628W 9914 00182 0123 +240 +231 044013 013 001 001 00
Member Since: September 2, 2009 Posts: 130 Comments: 21091
Recon hasn't reported for some time - am I right to be worried?
Member Since: Posts: Comments:
Quoting CybrTeddy:
HDOB hasn't come out in 14 minutes, so I think they're typing up a Vortex message.


Let's hope so. :)
Member Since: April 1, 2010 Posts: 9 Comments: 2699
1031. xcool
Member Since: September 26, 2009 Posts: 2 Comments: 15624
Clouds, showers, and the slight chance of thunder, will arrive from the south tonight, ahead of TS Colin, which has strengthened and re-developed. Colin is a threat to Bermuda. Winds and showers will increase overnight Friday with Tropical Storm conditions expected Saturday. TS Colin is expected to pass to our west late Saturday, with conditions easing through Sunday. Please check often for updates.

this is from the bermuda weather service
Member Since: Posts: Comments:
HDOB hasn't come out in 14 minutes, so I think they're typing up a Vortex message.
Member Since: July 8, 2005 Posts: 259 Comments: 23590
1027. IKE
Quoting ShenValleyFlyFish:


Believe it or not Bermuda is perfectly capable of looking out for itself:


Bermuda Public Forecast
Issued at 4:30 pm - Thursday, August 05, 2010
Small Craft Warning (Valid for Friday afternoon through Saturday )
Headline -
Breezy with a few showers, increasing through Friday.
Public Synopsis -
Clouds, showers, and the slight chance of thunder, will arrive from the south this evening, ahead of the main body of the remnants of Tropical Storm Colin. This system is likely to be upgraded to a Tropical Storm this evening, and is expected to pass to our west on Saturday. Please check often for updates regarding this system.
Tonight -
Cloudy with a few showers and a slight chance of thunder... Winds south-southwesterly moderate, increasing moderate in any heavier showers... Low near 26C/79F.
Friday -
Mix of sun & clouds, occasional showers,increasing overnight... Winds southerly moderate, increasing moderate in the afternoon, then moderate to strong with gusts to strong overnight... High near 30C/86F.
Saturday -
Overcast, rain and showers, risk thunder, easing overnight... Winds southerly strong gusts to gale force, soon increasing strong to gale force with gusts to gale force, easing southwesterly strong late night... Low near 23C/74F, high near 29C/85F.
Sunday -
Sunny breaks patchy rain or showers, easing later... Winds southwesterly moderate to strong, gradually easing southerly moderate... Low near 26C/78F, high near 30C/86F.
Monday -
A mix of sun and clouds, a few showers likely... Winds southerly moderate, easing south-southwesterly light to moderate later... Low near 26C/78F, high near 30C/86F.
Climate data recorded Wednesday, August 04, 2010, at the L.F.Wade International Airport -
Hours of sunshine: 11.6
Temperatures
Maximum: 29.9C/85.8F
Minimum: 26.1C/79F
Sea Surface: 28.8C/83.8F
Precipitation
Yesterday: 0.5mm/0.02"
August to date: 8.6mm/0.34"
Past 30 Days: 107.2mm/4.22"
The next scheduled forecast will be issued at 11:30 pm
- Meteorologist: Michelle Pitcher, Observer: Christa Gierlinger



Agree. I've read on here how well their buildings and houses are constructed.

And I've read their forecast.
Member Since: Posts: Comments:
Quoting StSimonsIslandGAGuy:
just waiting till 5 Drak, it will be 5 soon enough. Dozen people right now checking NHC over and over competing to post the advisory first.
I think that if there is no vortex message, they will not issue an advisory.
Member Since: September 2, 2009 Posts: 130 Comments: 21091
1025. Drakoen
Looks like the center has slipped underneath the convection:

Member Since: October 28, 2006 Posts: 57 Comments: 29905

Viewing: 1074 - 1024

Page: 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | 13 | 14 | 15 | 16 | 17 | 18 | 19 | 20 | 21 | 22 | 23 | 24 | 25 | 26 | 27 | 28 | 29 | 30 | 31 | 32 | 33 | 34 | 35 | 36 | 37 | 38 | 39 | 40 | 41 | 42 | 43 | 44 | 45 | 46 | 47 | 48 | 49 | 50 | 51 | 52 | 53 | 54 | 55Blog Index

Top of Page

About

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

Local Weather

Overcast
62 °F
Overcast