CSU leaves their hurricane forecast unchanged; 92L and Colin's remains worth watching

By: Dr. Jeff Masters , 2:38 PM GMT on August 04, 2010

Share this Blog
4
+

Tropical Storm Colin was ripped apart by wind shear yesterday, and the storm's remnants are passing just north of the northernmost Lesser Antilles Islands today. Most of the heaviest thunderstorms are passing north of the islands, as seen on Guadeloupe radar. Long range radar out of Puerto Rico also shows this. Colin's remains are in a rather unfavorable environment for re-development, since the disturbance is passing beneath an upper-level low pressure system with dry air and high wind shear. Wind shear is a high 20 - 25 knots over Colin's remains this morning. Recent satellite imagery shows that heavy thunderstorm activity has increased in intensity and areal coverage over the past few hours, though, and Colin's remnants will need to be monitored for re-development.

Forecast for Colin's remains
The latest SHIPS model forecast predicts that wind shear will drop from 15 - 25 knots today to a moderate 15 - 20 knots on Thursday. Wind shear will continue to decline over the weekend, and this relaxation of shear prompts most of the major models to predict re-development of Colin sometime in the next four days. NHC is giving Colin's remain a 20% chance of developing into a tropical depression by Friday morning. A major trough of low pressure is expected to move off the U.S. East Coast on Friday, and this trough will pull Colin to the northwest and cause it to slow down. By Friday, Colin will be moving at half of its current speed. 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 8pm EDT tonight. It currently appears that Colin will only be a threat to Bermuda and Canada.


Figure 1. Morning satellite image of Colin's remains and Invest 92L.

92L
A tropical wave (Invest 92) in the south-central Caribbean 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, or 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 20% chance of this disturbance developing into a tropical depression by Friday morning. This storm was being tagged as 98L yesterday; I'm not sure why it is being called 92L today.

CSU's forecast numbers for the coming hurricane season remain unchanged
A very active Atlantic hurricane season is on tap for 2010, according to the seasonal hurricane forecast issued today, August 4, by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). The CSU team continues to call for 18 named storms, 10 hurricanes, 5 intense hurricanes, and an Accumulated Cyclone Energy (ACE) index 185% of average. These are the same numbers as their June 2 forecast. Between 1950 - 2000, the average season had 10 named storms, 6 hurricanes, and 2 intense hurricanes. But since 1995, the beginning of an active hurricane period in the Atlantic, we've averaged 14 named storms, 8 hurricanes, and 4 intense hurricanes per year. The new forecast continues to call for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (50% chance, 31% chance is average) and the Gulf Coast (49% chance, 30% chance is average). The risk of a major hurricane in the Caribbean is also high, at 64% (42% is average.)

The forecasters cited four main reasons for an active season:

1) Moderate La Niña conditions should be present during the most active portion of this year's hurricane season (August - October). This should lead to reduced levels of vertical wind shear compared with what was witnessed in 2009.

2) Current SST anomalies are running at near-record warm levels. These very warm waters are associated with dynamic and thermodynamic factors that are very conducive for an active Atlantic hurricane season.

3) Very low sea level pressures prevailed during June and July over the tropical Atlantic. Weaker high pressure typically results in weaker trade winds that are commonly associated with more active hurricane seasons.

4) We are in the midst of a multi-decadal era of major hurricane activity, which began in 1995. Major hurricanes cause 80 - 85 percent of normalized hurricane damage.

Analogue years
The CSU team picked four previous years when atmospheric and oceanic conditions were similar to what we are seeing this summer. Those four years were 2005, the worst hurricane season of all time; 1998, which featured 3 major hurricanes, including Category 5 Hurricane Mitch; 1952, a relatively average year that featured just 7 named storms, but 3 major hurricanes; and 1958, a severe season with 5 major hurricanes. The mean activity for these five years was 17 named storms, 11 hurricanes, and 5 intense hurricanes, almost the same as the 2010 CSU forecast.

How accurate are the August forecasts?
The August forecasts by the CSU team over the past 12 years have had a skill 21% - 44% higher than a "no-skill" climatology forecast for number of named storms, hurricanes, intense hurricanes, and the ACE index (Figure 2). This is a good amount of skill for a seasonal forecast, and these August forecasts can be useful to businesses such as the insurance industry and oil and gas industry that need to make bets on how active the coming hurricane season will be. This year's August forecast uses a new formula, so we don't have any history on how the technique has behaved in the past. An Excel spreadsheet of their forecast skill (expressed as a mathematical correlation coefficient) show values from 0.61 to 0.65 for their previous August forecasts using different techniques, which is respectable.


Figure 2. Comparison of the percent improvement over climatology for May and August seasonal hurricane forecasts for the Atlantic from NOAA, CSU and TSR from 1999-2009 (May) and 1998-2009 (August), using the Mean Squared Error. The British firm Tropical Storm Risk (TSR) will issue their outlook for the 2010 Atlantic hurricane season on June 4. Image credit: Verification of 12 years of NOAA seasonal hurricane forecasts, National Hurricane Center.

The British private forecasting firm Tropical Storm Risk, Inc. (TSR) is scheduled to release their August forecast later today. NOAA will also be issuing their August forecast sometime in the next week.

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 Thursday 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: 1312 - 1262

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 | 55 | 56Blog Index

1312. HadesGodWyvern (Mod)
NO TSUNAMI THREAT TO AUSTRALIA

Issued by the Joint Australian Tsunami Warning Centre (JATWC) at 8:17 AM EST on

Thursday 05 August 2010

********************************************************************************

SUMMARY:

An undersea earthquake of magnitude 7.1 has occurred at 8:01 AM EST on Thursday

05 August 2010 near NEW BRITAIN REGION, P.N.G..

THERE IS NO TSUNAMI THREAT TO THE AUSTRALIAN MAINLAND, ISLANDS OR TERRITORIES.

For further details visit the Bureau web site www.bom.gov.au.

No further updates will be issued unless the situation changes.

********************************************************************************

DETAILS:

An undersea earthquake of magnitude 7.1 has occurred at 8:01 AM EST on Thursday

05 August 2010 near NEW BRITAIN REGION, P.N.G. (latitude 6.060S longitude 150.860E ).
Member Since: Posts: Comments:
1311. will45
Quoting nrtiwlnvragn:


Raw from NHC


thanks the recoder page is down for me
Member Since: Posts: Comments:
1309. HadesGodWyvern (Mod)
Earthquake Information (Earthquake Information)
Issued at 07:24 JST 05 Aug 2010

Occurred at (JST) Latitude
(degree) Longitude
(degree) Depth Magnitude Region Name
07:02 JST 05 Aug 2010 6.0S 150.8E 80km 7.0 New Guinea and its Vicinity


No Tsunami threat to Japan by this earthquake.
Member Since: Posts: Comments:
this is a free blog. if you dont like the questions being asked,then dont answer them.some of the folks on here are very cold,last time i looked,not every one on here was a meterologist.
Member Since: Posts: Comments:
Quoting weatherman12345:

MIAMI09, DO YOU THINK THE NHC WILL MENTION THE WAVE THAT CAME OFF THE COAST OF AFRICA??
Like Drakoen said earlier, with the ECMWF and GFS both in agreement on developing the feature into Danielle in 48 hours the NHC should very well mention it. IMHO, they should go straight to orange (30%).
Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting JenniferGirl:


America is the nation of dreamers and try-harders. :)


Thanks Jen, I don't think I've seen you on here before, welcome to the blog!
Member Since: July 1, 2008 Posts: 13 Comments: 7423
Quoting CybrTeddy:


They're flying tonight. Already airborne.

CT, isn't "D" the possible center fix? Please correct me if I am wrong :)

. ATLANTIC REQUIREMENTS
1. TROPICAL STORM COLIN
FLIGHT ONE -- TEAL 71
A. 05/0000, 0600Z
B. AFXXX 0204A COLIN
C. 04/2230Z
D. 18.3N 60.4W
E. 04/2230Z TO 05/0600Z
F. SFC TO 15,000 FT
Member Since: Posts: Comments:
Quoting CybrTeddy:


Where?
I guess WU will pick it up soon?

Member Since: Posts: Comments:
Quoting will45:


you using google earth or decoder page?


Raw from NHC
Member Since: Posts: Comments:
Colin appears to be blowing up, though all due to the TUTT, should get ripped apart somewhat tomorrow, may not survive. If it does, I'm looking at the remnants to be near the Bahamas, again, I will probably be wrong, but that's what I'm looking at, most storms sheared by TUTTs head more west then north.
Member Since: July 1, 2008 Posts: 13 Comments: 7423
1301. jeebsa
If a recon is on the way and they find a closed circulation than its a T.S again. The 8:00 report will be out before that so if Ex Colin is getting better organizes wouldn't they bump the % points until it is reclassified again?
Member Since: Posts: Comments:
Quoting Seflhurricane:
the tropical wave off the cape verde islands is now an Invest


Where?
Member Since: Posts: Comments:
Quoting thelmores:
Is recon flying Colin tonight? Or Not?

I thought they were supposed to be on station 8pm?

Too lazy to go look myself! LOL


They're flying tonight. Already airborne.
Member Since: Posts: Comments:
the tropical wave off the cape verde islands is now an Invest
Member Since: July 14, 2009 Posts: 0 Comments: 3029
1297. will45
Quoting nrtiwlnvragn:


False alarm, plane was leaving Keesler not St Croix. It does have its HDOB on for some reason.


you using google earth or decoder page?
Member Since: Posts: Comments:
any info from recon ??? cant get any online
Member Since: July 14, 2009 Posts: 0 Comments: 3029
1295. xcool
strong TS JMO
Member Since: September 26, 2009 Posts: 2 Comments: 15684
Is recon flying Colin tonight? Or Not?

I thought they were supposed to be on station 8pm?

Too lazy to go look myself! LOL
Member Since: September 8, 2005 Posts: 0 Comments: 3805
Quoting hurrkat05:
lol@reed hes a dreamer


America is the nation of dreamers and try-harders. :)
Member Since: Posts: Comments:
Quoting Hurricanes12:


The recon is supposed to get there at 8PM EST, so I doubt that there will be a significant update. However, if they find a closed circulation, they would most likely file a special TWO that will say they will start issuing advisories on TD/TS Colin. They just need that closed circulation. They have TS force winds already.


Agreed.

I have seen them delay the TWOs for a few minutes, but they will not have enough data to do that.
Member Since: Posts: Comments:
lol@reed hes a dreamer
Member Since: Posts: Comments:
BASED ON ALL AVAILABLE DATA A DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS NOT EXPECTED AND THERE IS NO TSUNAMI THREAT TO HAWAII. REPEAT. A DESTRUCTIVE PACIFIC-WIDE TSUNAMI IS NOT EXPECTED AND THERE IS NO TSUNAMI THREAT TO HAWAII.


http://www.weather.gov/ptwc/text.php?id=hawaii.2010.08.04.221119
Member Since: Posts: Comments:
We might see a mention of the African wave, seeing as our two most reliable models develop it by Friday.
Member Since: Posts: Comments:
Quoting nrtiwlnvragn:
Wheels up on Recon


False alarm, plane was leaving Keesler not St Croix. It does have its HDOB on for some reason.
Member Since: Posts: Comments:
1286. jeebsa
Quoting weatherman12345:
NEW POLL ON EX COLIN
8:00 PM TWO
A.20%
B.30%
C.40%
D.50%
E. STRAIGHT TO CODE RED
(D) <
Member Since: Posts: Comments:
Quoting FLdewey:
We are doom.


If you mean by Colin, you're wrong.
Member Since: Posts: Comments:
Quoting Drakoen:
Looks like it wants to get its status as a TS back:

Indeed. Surprisingly it only has 1 overshooting top.

Member Since: September 2, 2009 Posts: 130 Comments: 21194
Quoting KEEPEROFTHEGATE:
04L/XX/XX
MARK
19.93N/62.56W
KOTG you have it nailed if you look back , basically the same coordinates as mine,which was I think 19.5/63
Member Since: April 29, 2007 Posts: 0 Comments: 8010
Quoting weatherman12345:
NEW POLL ON EX COLIN
8:00 PM TWO
A.20%
B.30%
C.40%
D.50%
E. STRAIGHT TO CODE RED


E.
Member Since: Posts: Comments:
Quoting weatherman12345:
NEW POLL ON EX COLIN
8:00 PM TWO
A.20%
B.30%
C.40%
D.50%
E. STRAIGHT TO CODE RED


The recon is supposed to get there at 8PM EST, so I doubt that there will be a significant update. However, if they find a closed circulation, they would most likely file a special TWO that will say they will start issuing advisories on TD/TS Colin. They just need that closed circulation. They have TS force winds already.
Member Since: Posts: Comments:
Quoting FLdewey:
We are doom.



doom i say where all doom
Member Since: May 21, 2006 Posts: 5091 Comments: 115354
computer is flipping out. keeper did ya see?

MAP 7.0 2010/08/04 22:01:45 -5.804 150.767 54.0 NEW BRITAIN REGION, PAPUA NEW GUINEA
Member Since: August 11, 2008 Posts: 3 Comments: 1679
Quoting nyhurricaneboy:


A

E of course
Member Since: Posts: Comments:
Colin gives the appearence as if it's moving N, but that's because the shear is coming from the SW, shearing the clouds to the N, giving the appearence that the storm is moving to the NNW or to the N, when it's actually moving to the WNW/NW.
Member Since: Posts: Comments:
Quoting louisianaboy444:
That would be the best scenario for the GFS to verify....the first five storms do not affect the U.S. or any other land masses with the exception of Alex i can live with that this season has looked good for the U.S. thus far


thats a good thing.. Just got a 20KW generac guardian installed hoping I do not have to use it!!!
Member Since: Posts: Comments:
1275. will45
Quoting calder:
is anyone having problems getting recon info in google earth?


i havent tried Google but the recon decoder page is down on my end at least
Member Since: Posts: Comments:
Quoting weatherman12345:
NEW POLL ON EX COLIN
8:00 PM TWO
A.20%
B.30%
C.40%
D.50%
E. STRAIGHT TO CODE RED


A
Member Since: Posts: Comments:
1273. FLdewey
We are doom.
Member Since: August 19, 2008 Posts: 42 Comments: 6269
Quoting JenniferGirl:


I haven't noticed any mishaps on the blog today whatsoever until this evening.
It's ok, I'm moving on just like Taz suggested, should have minded my own business anyway , but personally I don't like to see people treated cold, but ignorance speaks for itself don't it!
Member Since: April 29, 2007 Posts: 0 Comments: 8010
1270. Vero1
Quoting calder:
is anyone having problems getting recon info in google earth?


Not displayed on mine yet either.
Member Since: Posts: Comments:
1269. will45
Quoting Snowlover123:


The GFS doesn't even develop Earl...


dont quote a troll please
Member Since: Posts: Comments:
1268. Engine2
Quoting Snowlover123:


Reedzone, I'm backing you up. The models need to get it straight, that this thing is already moving differently, than what they're forecasting.

I also agree - there are too many variables, we don't have a center to fixate on and its not traveled as expected to begin with - lets give it time.
Member Since: Posts: Comments:
Quoting reedzone:


Not arguing MY PREDICTION.. get it in your head.. It's a free country I can post whatever the heck I want.


Reedzone, I'm backing you up. The models need to get it straight, that this thing is already moving differently, than what they're forecasting.
Member Since: Posts: Comments:
1266. calder
is anyone having problems getting recon info in google earth?
Member Since: July 26, 2006 Posts: 0 Comments: 419
1265. Ossqss
Quoting atmosweather:


It's pretty common for La Nina's to extend more than 24 months after switching from El Nino in a 6 month period. 1998-99 is one clear example I remember. I'd not be surprised if we see a strong La Nina (-2.0 or further) persist until next fall.


This year is very similar to 1998 in many respects including the probability of a long strong La Nina .

Member Since: Posts: Comments:
1264. Drakoen
Looks like it wants to get its status as a TS back:

Member Since: October 28, 2006 Posts: 57 Comments: 30615
Quoting weatherman12345:
so florida is out of the picture for Ex. Colin right??


If models are correct, it will recurve and not impact US.
Member Since: Posts: Comments:
Quoting MiamiHurricanes09:
They took off at 6:30PM EDT, however they arrive at 8PM EDT.

I. ATLANTIC REQUIREMENTS
1. TROPICAL STORM COLIN
FLIGHT ONE -- TEAL 71
A. 05/0000, 0600Z
B. AFXXX 0204A COLIN
C. 04/2230Z
D. 18.3N 60.4W
E. 04/2230Z TO 05/0600Z
F. SFC TO 15,000 FT

This is where they expect to find the center?..uh..ok..
Member Since: Posts: Comments:

Viewing: 1312 - 1262

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 | 55 | 56Blog 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

Partly Cloudy
27 °F
Partly Cloudy