Early 2011 Atlantic Hurricane Season Forecasts

By: Dr. Jeff Masters , 6:22 AM GMT on April 07, 2011

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Hi everybody, this is Dr. Rob Carver filling in for Dr. Masters. 

A continuation of the pattern of much above-average Atlantic hurricane activity we've seen since 1995 is on tap for 2011, according to the latest seasonal forecast issued April 6 by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). They are calling for 16 named storms, 9 hurricanes, and 5 intense hurricanes. An average season has 10 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast is nearly identical to their forecast made in December, which called for 17 named storms, 9 hurricanes, and 5 intense hurricanes. Only six seasons since 1851 have had as many as 17 named storms; 19 seasons have had 9 or more hurricanes. The 2011 forecast calls for a much above-average chance of a major hurricane hitting the U.S., both along the East Coast (48% chance, 31% chance is average) and the Gulf Coast (47% chance, 30% chance is average). The Caribbean is forecast to have a 61% chance of seeing at least one major hurricane (42% is average.) Five years with similar pre-season November atmospheric and oceanic conditions were selected as "analogue" years that the 2011 hurricane season may resemble: 2008, 1999, 1996, 1955, and 2006.  The first four years listed all had neutral to La Niña SST's during hurricane season, while 2006 had El Niño SST's.  The average activity for these years was 12.6 named storms, 7.8 hurricanes, and 4.8 major hurricanes.

This year, the forecasters have introduced a new statistical model for their  April forecasts.  There are four components in this model:

1. Average sea-level pressure in March around the Azores in the subtropical Atlantic.

2. The average of January through March sea-surface temperatures (SST's) in the tropical Atlantic off the coast of Africa.

3. Average sea-level pressure in February and March for the southern tropical Pacific ocean west of South America.

4. Forecasts of September's SST in the tropical Pacific using a dynamical model from the European Centre for Medium-Range Weather Forecasts (ECMWF) 

The first two components are loosely linked together.  Statistical studies have shown that a weaker subtropical high near the Azores, combined with warmer SST's off the coast of Africa in March are associated with weak winds near the surface and aloft from August to October.  This decrease in wind speeds reduces wind shear which can disrupt forming storms.  These March conditions also are associated with warmer SST's in August to October, which is also favorable for more tropical storms.   For this forecast, the first component is strongly favorable for increased hurricane activity, while the second component is weakly negative.

The last two components represent the changes in sea-surface temperature and sea-level pressure that are the El Niño-Southern Oscillation (ENSO).  Briefly speaking,  El Niño conditions (warm sea-surface temperatures) are not favorable for Atlantic hurricanes.  For more info on ENSO and hurricanes, Jeff has this article.

Using the ECMWF model as guidance (see Figure 1), the CSU group believes that SST's in the tropical Pacific will be neutral (less than 0.5°C from normal).  This would have a small negative effect on hurricane activity.  However, the tropical Pacific sea-level pressure shows that the atmosphere looks like a La Niña event is still going on.  This is strongly favorable for Atlantic hurricane activity in the CSU group's model.

Figure 1. Forecasts of El Niño conditions by 20 computer models, made in March 2011. The ECMWF forecast used by the CSU group is represented by the dark orange square.  The forecasts for August-September-October (ASO) show that 5 models predict El Niño conditions, 7 predict neutral conditions, and 5 predict a weak to moderate La Niña. El Niño conditions are defined as occurring when sea surface temperatures in the Equatorial Pacific off the coast of South America ( the "Niño 3.4 region) rise to 0.5°C above average (top red line). La Niña conditions occur when SSTs in this region fall to 0.5°C below average. Image credit: Columbia University.

How accurate are the April forecasts? While the formulas used by CSU do well in making hindcasts--correctly modeling the behavior of past hurricane seasons--their April hurricane season forecasts have had no skill in predicting the future. This year's April forecast is using a new system and has not yet produced a verified forecast.  The scheme used in the past three years successfully predicted active hurricane seasons for 2008 and 2010, but failed to properly predict the relatively quiet 2009 hurricane season. A different formula was used prior to 2008, and the April forecasts using that formula showed no skill over a simple forecast using climatology. CSU maintains an Excel spreadsheet of their forecast errors ( expressed as a mathematical correlation coefficient, where positive means a skilled forecast, and negative means they did worse than climatology) for their their April forecasts. For now, these April forecasts should simply be viewed as an interesting research effort that has the potential to make skillful forecasts. The next CSU forecast, due by June 1, is the one worth paying attention to. Their early June forecasts have shown considerable skill over the years.


Figure 2.
Accuracy of long-range forecasts of Atlantic hurricane season activity performed by Phil Klotzbach and Bill Gray of Colorado State University (colored squares) and Tropical Storm Risk, Inc. (colored lines). The CSU team's April forecast skill is not plotted, but is less than zero. The skill is measured by the Mean Square Skill Score (MSSS), which looks at the error and squares it, then compares the percent improvement the forecast has over a climatological forecast of 10 named storms, 6 hurricanes, and 2 intense hurricanes. TS=Tropical Storms, H= Hurricanes, IH=Intense Hurricanes, ACE=Accumulated Cyclone Energy, NTC=Net Tropical Cyclone Activity. Image credit: TSR.

2011 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.

The  British  private  forecasting  firm  Tropical Storm Risk, Inc.  (TSR),   issued  their  2011  Atlantic hurricane season forecast on April 5. They are also calling for  a  very  active  year: 14. 2 named storms, 7.5 hurricanes, and 3.6 intense hurricanes. We would round that to 14 named storms, 8 hurricanes, and 4 intense hurricanes.   This  compares to their forecast issued in December of 15.6 named storms, 8.4 hurricanes,   and intense hurricanes. TSR predicts a 55%  chance  of  an  above-average  hurricane season, 28% chance of a near-normal season, and only a 17%  chance  of  a  below normal season. TSR bases their April forecast on predictions  that  sea  surface temperatures this fall in the tropical  Atlantic  will  be  above  about  0.08°C above average, and trade  wind  speeds  will  be  about 0.2  m/s  slower  than average.  The decrease in the trade wind speeds is favorable for enhanced hurricane activity, while the forecast SST's are expected to be neutral for hurricane activity.

TSR puts their skill level right next to the forecast numbers: 13% skill above chance at forecasting the number of named storms, 11% skill for hurricanes, and 10% skill for intense hurricanes. That's not much skill, and really, we have to wait until the June 1 forecasts by CSU, NOAA, and TSR to get a forecast with reasonable skill.

Rob's critiques of the April forecasts
I have to note that Jeff and I wrote this article together.  He wrote the general framework before the forecasts were issued, while I wrote the details based on the actual forecasts.  So the preceding text is a joint production.  However, I have a few observations to make that are my responsibility alone.

First, I am disappointed that the CSU group has changed forecast models only after three seasonal forecasts.  This makes it very difficult to assess the skill of the current forecast using past performance.  This is very important for forecast users, and they do it everyday.  For example, I tend to discount a forecast of rain if it comes from a source that over-forecasts rain (The boy who cried wolf problem).

In the documentation that came with the April forecast, the CSU group argue that the hindcasts show the new forecast model has skill.  However, I think hindcasts are a poor substitute for real forecasts in understanding the skill of a statistical forecast model, like that of the CSU's group.  As Jeff noted, the previous forecast model did well with the hindcasts and yet had mixed results with the actual forecasts.  This does not give me confidence that the new forecast model will be superior to the previous model.

From a philosophical viewpoint, I am inherently cautious about statistical forecast models like the one used by the CSU group.  Essentially, they look at what happened in the past and use that to predict the future.  However, for making forecasts, we assume that the relationships in space and time between the predictors (such as the average March sea-level pressure around the Azores) and the predictands (Atlantic hurricane activity) does not change as we move forward in time.  In a world with climate change, that's a tricky assumption to make.

In any event, it is customary in the meteorological community to continue running older forecast guidance models after the introduction of newer models.  This allows forecasters and forecast users to leverage their knowledge of the forecast skill of the older model and gain insight into the forecast skill of the new model.  The CSU group really should have included the forecast from the previous statistical forecast system in this forecast.     

I am uneasy with some of the methodology choices made in implementing the forecast model.  Data for the first three predictors was obtained from the Climate Forecast System Reanalysis (CFSR), NOAA's newest and most advanced reanalysis product.  However, CFSR data for 2010 and 2011 has not been released yet, so the CSU group used NCEP/NCAR Reanalysis (NNR), NOAA's first-generation reanalysis, to fill in the gaps.  Due to differences in design, resolution, etc., CFSR and NNR can have different depictions of the state of the atmosphere.  So using NNR's March 2011 average SLP instead of CFSR's could alter the forecast in unexpected ways.  It would be interesting to see how CFSR's 2010-2011 data changes the results. 

In any event, we will have to wait and see what the Atlantic hurricane season of 2011 brings.

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Quoting Jedkins01:


Yeah I voted when I got my first chance, now I'm just questioning whether I should or not anymore, I'm 20 now, was 18 then. I'll be hitting the big 21 this October 21st


1. Then the other guys win.
2. (my opinion only) If you don't vote then you have given up all right to complain because you didn't take part in the process.
3. People have died for the right to vote, and still die to this day trying to vote in some countries.

again, just my opinion
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Quoting kimoskee:
Evening all. Stupid question...
It is possible to change your username?
I want to change mine to reflect my location.


You can't change it without creating a new account attached to a different e-mail address.
Member Since: Posts: Comments:
Quoting GeoffreyWPB:
The big picture...

Beggining to see waves that don't just fall apart when they exit Africa. Seems like all the real first african waves tell you how a season is going to be...
USUALLY if a season is normal or not active, the waves emerge in mid-late May, If its a above average season you see the waves emerge in early May.
First Wave Emerges~
2004: May 21 El Nino
2005: May 02 Neutral
2006: May 11 El Nino
2007: May 21 Strong La Nina
2008: May 02 Neutral
2009: May 13 El Nino
2010: May 02 Strong La Nina
2011: N/A
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Quoting aquak9:


you do pretty good here, sweety. Sorry if I was ever real harsh to you. I'll be nicer from now on.


hahahahohohohohehehehe

Oh, sorry. ;)
Member Since: August 22, 2008 Posts: 12 Comments: 6010
Evening all. Stupid question...
It is possible to change your username?
I want to change mine to reflect my location.
Member Since: Posts: Comments:
Quoting HurricaneDean07:
I'm with ya ben. I've been on here since last October, but my knowledge of hurricanes can cut you.
I studied Weather in 3rd grade, and began spreading my knowledge of hurricanes ever since I started watching them(That's why my user name is Hurricane Dean) it was the first storm I ever tracked. I've also started my own hurricane site, and can free hand North/South America, Western Africa, and Western Europe vividly by memory. So i have no trouble making hurricane maps on blank paper. Actually it's really useful...


I make hurricane maps all the time. I've been tracking Hurricanes Gustav & Ike, just about every named storm in the 2008 Hurricane Season plus the very end of the 2007 season.
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The Masters, the first major of the 2011 PGA Tour, is underway in Augusta, Ga. Weather has left its mark on this tournament over the years and this week is no exception.

According to The Associated Press, Tuesday's practice round was delayed by 45 minutes as workers cleaned up debris left behind by a line of storms which moved though during the early morning hours of Tuesday.

The storms toppled trees and knocked down power lines in portions of the Augusta area.

As we look at the forecast through Sunday, you may be thinking about a green t-shirt rather than a green jacket. High temperatures will warm to the middle or upper 80s over the weekend. If you are lucky enough to be in attendance, be sure to take your sunscreen!

Member Since: April 2, 2011 Posts: 0 Comments: 2278
The big picture...

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I'm with ya ben. I've been on here since last October, but my knowledge of hurricanes can cut you.
I studied Weather in 3rd grade, and began spreading my knowledge of hurricanes ever since I started watching them(That's why my user name is Hurricane Dean) it was the first storm I ever tracked. I've also started my own hurricane site, and can free hand North/South America, Western Africa, and Western Europe vividly by memory. So i have no trouble making hurricane maps on blank paper. Actually it's really useful...
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338 belizeit " [Earthquake map showing Belize between the Isthmus of Tehuantepec earthquake and the Gulf of Honduras earthquake earlier today] at my door front.
I sometimes wonder what it would take to drench the coast of Belize. Last year we had a 7.2 a little closer to Belize which shook us all up but it caused no tsunami. But history tells us that Belize has been affected by tsunamis already.

Belize has a long lead of shallow water off of its coast, which is what is needed to turn short&long ocean-going tsunamis into really tall BigWaves by the time they reach then pass over the shoreline.

It would take a Caribbean earthquake that breaks the crust up and/or down to cause a tsunami. Apparently you've been lucky to only experience quakes that move the crust side-to-side.
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Hey Everyone, I'm not going to post a new blog until JUNE 1, but I do feel like posting my predictions. I came up with these on April 4 and it just so happens that CSU nailed my #'s on the nose. So here you go...
16 NS, 9 HUR, 5 INT.HUR, Although I do believe that Texas, Louisiana, and the caribbean will be the JUNE/JULY/AUGUST Targets. But once you get 2-4 months down the road it gets pretty blurry... Won't be back on the blog until next week so, have a good Friday, Saturday, and Sunday.
Dean out...
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Quoting TomTaylor:
yes.
dang starting early


Ya but im not too arrogant about it. Some of my friends in school are always asking me what's the weather gonna be days ahead in case one of them wants to go to the beach or has a scheduled baseball practice or whatever.
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Quoting hurricaneben:
Does anyone think we may see our first named storm before June 1st.
yes.
Quoting hurricaneben:


No, you're not. I'm only 12 1/2 years old, turning 13 in October. I'm probably the youngest here but my knowledge of hurricanes is as sharp as a knife, no intention to brag.
dang starting early
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Quoting aquak9:


you do pretty good here, sweety. Sorry if I was ever real harsh to you. I'll be nicer from now on.


Thanks, you were never really harsh just occosionally you kinda got a bit critizing but thats OK. I do not understand why is Grothar teased so much, however.
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Quoting CybrTeddy:


I do.


Well I think I may see a subtropical storm well East of North Carolina about 200 hours out on the NCEP model--so at last we have an even remote chance of perhaps seeing...Arlene? It reminds me a tad bit of Ana in 2003 which also formed in April and affected Bermuda, I think.
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Quoting hurricaneben:


No, you're not. I'm only 12 1/2 years old, turning 13 in October. I'm probably the youngest here but my knowledge of hurricanes is as sharp as a knife, no intention to brag.


you do pretty good here, sweety. Sorry if I was ever real harsh to you. I'll be nicer from now on.
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Quoting hurricaneben:
Does anyone think we may see our first named storm before June 1st.


I do.
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Quoting TomTaylor:

woah didn't realize you were that young! you aren't much older than me. I thought I was like an endangered species on this blog.



haha same here! I didn't realize you were that young either
Member Since: August 21, 2008 Posts: 0 Comments: 7945
7.1 off Japan

The April 7, 2011 earthquake near the east coast of Honshu, Japan occurred as a result of thrust/reverse faulting on or near the subduction zone plate boundary between the Pacific and North America plates.... This earthquake can be considered an aftershock of the March 11, 2011 Mw 9.0 Tohoku earthquake. The aftershock sequence of that event has been ongoing since March 11, and has included 58 earthquakes of M 6 or greater up until April 7 2011, two of which were greater than M 7 (M7.7 and M7.9, both on March 11).

Link
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Quoting TomTaylor:

woah didn't realize you were that young! you aren't much older than me. I thought I was like an endangered species on this blog.


No, you're not. I'm only 12 1/2 years old, turning 13 in October. I'm probably the youngest here but my knowledge of hurricanes is as sharp as a knife, no intention to brag.
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Whats up with USA i here a lot of shut down talks
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Quoting Jedkins01:


Yeah I voted when I got my first chance, now I'm just questioning whether I should or not anymore, I'm 20 now, was 18 then. I'll be hitting the big 21 this October 21st

woah didn't realize you were that young! you aren't much older than me. I thought I was like an endangered species on this blog.
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Does anyone think we may see our first named storm before June 1st.
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Quoting TomTaylor:
Next election will be the first time I can legally vote, so I will. I just think the whole debate is stupid. There are many voters who change there minds on their party from election to election. but when it comes to internet debates, nobody every changes their stance on politics.

It just ends up being two sides arguing to two brick walls.


Yeah I voted when I got my first chance, now I'm just questioning whether I should or not anymore, I'm 20 now, was 18 then. I'll be hitting the big 21 this October 21st
Member Since: August 21, 2008 Posts: 0 Comments: 7945
Quoting SWFLgazer:


One should vote every chance they get, if nothing else to preserve your right to bitch about what the person who won does. How can you bitch if you voluntarily gave up your right to choose and instead gave that choice to someone else?
You're right. But this is a weather blog, so please don't drag politics in here

And I never said you shouldn't vote...
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Quoting TomTaylor:
Next election will be the first time I can legally vote, so I will. I just think the whole debate is stupid. There are many voters who change there minds on their party from election to election. but when it comes to internet debates, nobody every changes their stance on politics.

It just ends up being two sides arguing to two brick walls.


One should vote every chance they get, if nothing else to preserve your right to bitch about what the person who won does. How can you bitch if you voluntarily gave up your right to choose and instead gave that choice to someone else?
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Quoting Hoff511:
Link


Interesting note... from that article:

"According to long-term records (since about 1900), we expect about 17 major earthquakes (7.0 - 7.9) and one great earthquake (8.0 or above) in any given year."

That's an avg. annual total of earthquakes >7.0 of: 18
Current 2011 count for earthquakes >7.0 is: 8



Given that it's only the 97th day of the year, if we continue to have major earthquakes at this rate we will have roughly 30 major earthquakes this year, about twice the average number.

I haven't found any studies attempting to predict what the rest of the year might be like, but I'd expect things to start quieting down soon if history is any indication. That said, even if things do calm down (and let's hope they do), the first part of 2011 has been a period of above-average earthquake activity.

It'll be interesting to see how the rest of the year pans out, but it might be a little soon to quit your job in preparation for the end of days... :)
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Quoting Jedkins01:


Yeah it will be wacked, politics is so stupid, I may not vote at all next election. Our system has grown to the point where the hope of honest leadership that actually serves the people is all but completely hopeless. Ive trusted people too much for too long.
Next election will be the first time I can legally vote, so I will. I just think the whole debate is stupid. There are many voters who change there minds on their party from election to election. but when it comes to internet debates, nobody every changes their stance on politics.

It just ends up being two sides arguing to two brick walls.
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Quoting jitterboy:

Yeah sorry about that. I copied straight off of my browser bar. Google "Are Earthquakes Really on the Increase" and it will come up. It is two years old you are right about that. So they have changed their minds on that?


I saw something on NBC and CNN that said so, but I do not trust either. I have not been able to find a peer reviewed publication yet. I have been looking. From my own experience coming from CA, I have been paying pretty close attention for many years, it does seem so to me.
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Bit late for the conversation on a previous blog, but just got reminded of
another ThirdWorld DDT vs Malaria tale of unintended consequences.
The DDT killed the mosquitoes, then villagers' roofs started caving in.
And then the number sylvatic plague and typhus infections skyrocketed.
How? Read the link.

BTW, it was the dried vines used to lash the thatching together that was eaten, not the thatching.
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Quoting Hoff511:


I clicked on your link and it was a 404 page not found. Was this the article you were referring to?
http://earthquake.usgs.gov/learn/topics/increase_ in_earthquakes.php
If so, that article is 2 years old and I believe they have changed their thinking I don't have a direct link. Anybody?

Yeah sorry about that. I copied straight off of my browser bar. Google "Are Earthquakes Really on the Increase" and it will come up. It is two years old you are right about that. So they have changed their minds on that?
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Quoting RastaSteve:


what part of Tampa are you from?

The part just outside San Juan would be my guess...
Member Since: November 8, 2009 Posts: 4 Comments: 13720
Quoting ShenValleyFlyFish:
FWIW addition to the caster list

Troll caster: blog-member who concentrate on identifying and outing trolls.


And the somewhat related Fodder caster: one who concentrates on feeding trolls.
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Link
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Quoting TomTaylor:
Oh, this just made me thing of how the blog will be during the next elections.

I've never been on this blog during Presidential elections, but I can't imagine how it will be come 2012 near the end of hurricane season, when we still got a lot of blog members since it will still be hurricane season, but there won't be much to talk about hurricane wise since the season will be almost over, and the elections & campaign will be all over the media.

Recipe for disaster.

I'm jealous. Must be nice living there. And I've been watching the sat loops, southern central american has been getting quite a few thunderstorms in


Yeah it will be wacked, politics is so stupid, I may not vote at all next election. Our system has grown to the point where the hope of honest leadership that actually serves the people is all but completely hopeless. Ive trusted people too much for too long.
Member Since: August 21, 2008 Posts: 0 Comments: 7945
Quoting jitterboy:
Is the number of earthquakes increasing? Apparently not according to the USGS. Some of the apparent increase is due to more seismic sensors- some of it is due to increased awareness of occurring earthquakes (ie the internet).
http://earthquake.usgs.gov/learn/topics/increase_ in_earthquakes.php


I clicked on your link and it was a 404 page not found. Was this the article you were referring to?
http://earthquake.usgs.gov/learn/topics/increase_ in_earthquakes.php
If so, that article is 2 years old and I believe they have changed their thinking I don't have a direct link. Anybody?
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Quoting Jedkins01:
Hey guys, Donald trump is actually being considered a possible republican presidential candidate, better yet, he's using the "Obama isn't an American citizen" propaganda right now. Doesn't he realize that was disproven a while ago as a right wing lie?

Are they really that desperate?
Oh, this just made me think of how the blog will be during the next elections.

I've never been on this blog during Presidential elections, but I can't imagine how it will be come 2012 when we still got a lot of blog members since it will still be hurricane season, but there won't be much to talk about hurricane wise since the season will be almost over, and the elections & campaign will be all over the media.

Recipe for disaster.

Quoting hurricaneeye:
This is hurricaneeye reporting from Costa Rica.

The rainy season has already started in the South Pacific, Costa Rica,around two weeks earlier than usual.
This year, we've had 4 thunderstorms in the first 7 days of April alone(really uncommon).

Looking forward 2011 Hurricane Season!



I'm jealous. Must be nice living there. And I've been watching the sat loops, southern central american has been getting quite a few thunderstorms in
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Is the number of earthquakes increasing? Apparently not according to the USGS. Some of the apparent increase is due to more seismic sensors- some of it is due to increased awareness of occurring earthquakes (ie the internet).
http://earthquake.usgs.gov/learn/topics/increase_ in_earthquakes.php
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FWIW addition to the caster list

Troll caster: blog-member who concentrate on identifying and outing trolls.
Member Since: Posts: Comments:
Is the number of earthquakes increasing? Apparently not according to the USGS. Some of the apparent increase is due to more seismic sensors- some of it is due to increased awareness of occurring earthquakes (ie the internet).
http://earthquake.usgs.gov/learn/topics/increase_ in_earthquakes.php
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This is hurricaneeye reporting from Costa Rica.

The rainy season has already started in the South Pacific, Costa Rica,around two weeks earlier than usual.
This year, we've had 4 thunderstorms in the first 7 days of April alone(really uncommon).

Looking forward 2011 Hurricane Season!



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Hey guys, Donald trump is actually being considered a possible republican presidential candidate, better yet, he's using the "Obama isn't an American citizen" propaganda right now. Doesn't he realize that was disproven a while ago as a right wing lie?

Are they really that desperate?
Member Since: August 21, 2008 Posts: 0 Comments: 7945
Quoting sunlinepr:


My advice is :

Take a look on Dr. Jeff Masters' WunderBlog Archived Entries

Link Link

Read through some days and get the feeling on how the blog behaves...

You will learn to identify bloggers, their attitudes and their likes...

Then, stay calm, be informative, be friendly with those who are friendly and avoid provocations



Alright...
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Quoting RastaSteve:


what part of Tampa are you from?


North Tampa, more of like the northeast suburbs really.
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Afternoon all.
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Quoting FLweathergirliee:


Thanks at least someone doesn't treat me as an outcast I see


My advice is :

Take a look on Dr. Jeff Masters' WunderBlog Archived Entries

Link Link

Read through some days and get the feeling on how the blog behaves...

You will learn to identify bloggers, their attitudes and their likes...

Then, stay calm, be informative, be friendly with those who are friendly and avoid provocations
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A earthquake at my door front . I somtimes wonder what it would take to dren ch the coast of Belize last year we had a 7.2 a little closer to Belize wich shook us all up but it caused no tsunami. But history tells us that Belize has been afected by tsunamis already .
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337. Skyepony (Mod)
The earth orientation was thrown more by the Japan earth quake than 2010 Chile or 2004 Sumatra.


Our first estimates of the megaquake of Honshu, Nothern Japan Coast , at 5:46 UT on polar motion. According to the preliminary US Geological Survey and Harvard University seismic parameters used with Dahlen's dislocation model (1973), the principal axis of inertia

with highest moment of inertia (also called figure axis, closed to
symetry axis) was displaced by about 15 cm at the earth surface in the
direction 135° East (value confirmed by R. Gross, JPL, with another
model). The effect is larger than for Chili (February 2010) and Sumatra
(Dec. 2004) earthquakes (see below corresponding news). This could be
observed as a step in the so-called excitation function, deduced from
the determination of pole coordinates by space geodesy. But such a step
could be hardly discernible from common hydro-meteorological processes.
The oceanic angular momentum still lacking, only next months will tell
us wether something is detectable.




Modeled co-seismic shift of the main inertia pole since January 2004:




Modeled co-seismic shift of the rotation pole since January 2004:

http://hpiers.obspm.fr/eop-pc/index.php?index=new s
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Quoting RitaEvac:
Big smoke plume from fire in Mexico SW of Laughlin Air Force Base in TX. Going directly over air force base


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Good lord, people. It's not the end of the world. The world is having a lot of earthquakes because the tectonic tension is being released all at the same time.

For example, try to move to things that won't slide easily against each other. They will move in spurts. Same concept here, except it has spanned the last 8 years because of the speed of the tectonic plates.

Regardless of sensationalist apocalyptic talk, the JTWC has released the best track data for 2010.
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Quoting Cotillion:
Something vaguely interesting and of use to any meteorologically themed quiz, I suppose:

'The Earth sees about 760 thunderstorms every hour, scientists have calculated.

The figure, unveiled at the European Geosciences Union meeting in Vienna, is substantially lower than numbers that have been used for nearly a century.

The new research uses a global network of monitoring stations that detect the electromagnetic pulses produced by major bolts of lightning.

It confirms that thunderstorms are mainly a tropical phenomenon - and the Congo basin is the global hotspot.'

link

From the article:

"Thunderstorms cluster in the centre of continents in the tropics, with the Congo basin standing out.

"That's perhaps because it's drier there than in the Amazon, for example - thunderstorms seem to form more easily in drier conditions," Dr Price told BBC News."


It's interesting that the Congo basin sees more lightning than the Amazon, because as the article hints at, the Amazon receives much more rain.

I'm guessing the reason for greater lightning in the Congo is because the drier air in the Congo allows for greater heating allowing for greater lift & instability. Meanwhile, the Amazon is more uniformly moist, meaning more cloud cover and less opportunity for significant heating, like the Congo sees.

thats my guess


Here's a map of the global lightning strike density. view in another tab to enlarge

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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.