First Klotzbach / Gray 2010 Atlantic season forecast

[cycloneye]

Dr Phil Klozbach / Dr William Gray first 2010 forecast is out and forsee an active season unfold.However,I dont give much credence to this forecast in particular as its too far away from June 1rst.I always look for the April forecast as it has much more data,but its always interesting to read what is their analysis looking ahead towards the 2010 season.They went with a set of numbers like NOAA does,a spread of them by category.

http://hurricane.atmos.colostate.edu/Fo ... ec2009.pdf

Below is the abstract of the report.

ABSTRACT
Information obtained through November 2009 indicates that the 2010 Atlantic hurricane season will be somewhat more active than the average 1950-2000 season. We estimate that activity will return to levels more typical of years during an active era, such as what we have experienced since 1995. We expect to see approximately 11-16 named storms, 6-8 hurricanes and 3-5 major hurricanes occur during the 2010 hurricane season. These numbers are based on the average of our statistical model, our analog model and qualitative adjustments and insights. At this point, there is too much uncertainty in what large-scale parameters will be in August-October of next year to issue a forecast for specific numbers. However, we do feel that we are in a favorable position for issuing an early December forecast this year, since we believe the odds of a multi-year El Niño event are quite small. Because we are predicting an above-average hurricane season in 2010, the probability of U.S. and Caribbean major hurricane landfall is estimated to be above the long-period average. This forecast is based on a new extended-range early December statistical prediction scheme that utilizes 58 years of past data. The influences of El Niño conditions are implicit in these predictor fields, and therefore we do not utilize a specific ENSO forecast as a predictor. We expect to see the moderate to strong El Niño event that is currently in progress diminish by the 2010 Atlantic hurricane season.

Named Storms=11-16
Hurricanes=6-8
Major Hurricanes=3-5

[HURAKAN]

I agree. It's normal to have an above normal season after a slow one.

[cycloneye]

Also Sandy,is rare to have two years in a row having El Nino.

[srainhoutx]

Actually I'm not surprised at this. What does catch my eye is the "Unpredictability " of the current ENSO Event. This will likely perk some ears during this strange "Winter Season" though.

[cycloneye]

Actually I'm not surprised at this. What does catch my eye is the "Unpredictability " of the current ENSO Event. This will likely perk some ears during this strange "Winter Season" though.

March will be the key month in my view to see how the ENSO factor is doing to then have a good idea of how the 2010 atlantic season will turn out.

[Blown Away]

Luis,
Do we know what the analog years will be for the 2010 season?

[cycloneye]

Luis,
Do we know what the analog years will be for the 2010 season?

You didnt read the whole report as is way down.

Here they are:

Table 9: Analog years for 2010
1952
1958
1964
1966
1998
2003
2007

[Macrocane]

I agree about an active season, all after-El Niño season have been active since the active period of the AMO began. Just take a look at 1995, 1998, 2003, 2005 all of them were very active and only 2007 was near average. I also think that we may have a cat 5 hurricane next year, 1998, 2003, 2005 and 2007 had at least one.

[cycloneye]

Klotzbach / Gray 2010 analog year graphics:Plenty of Cape Verde systems and somewhat less activity in the GOM in the analogs.

1952



1958



1964



1966



1998



2003



2007

[Blown Away]

Looks like a potential busy season for the Eastern Caribbean and Florida based on the 2010 analog years (2007,2003,1998,1966,1964,1958,1952).

[cycloneye]

Yes,it looks like the Caribbean folks will have to watch to the east many times with those analogs.

By the way,I just found out that the U.K. folks from Tropical Storm Risk also see an active 2010 season.

http://www.tropicalstormrisk.com/

[cycloneye]

Below is Dr Jeff Masters take on the forecasts from Colorado State University and Tropical Storm Risk:

Posted by: JeffMasters, 3:27 PM GMT on December 10, 2009

A return to the pattern of above-average Atlantic hurricane activity we've seen since 1995 is on tap for 2010, according to the latest seasonal forecast issued today by Dr. Phil Klotzbach and Dr. Bill Gray of Colorado State University (CSU). In a departure from their usual forecasts, the Klotzbach/Gray team is issuing a range of numbers for storms, instead of forecasting a specific number. They are calling for 11 - 16 named storms, 6 - 8 hurricanes, and 3 - 5 intense hurricanes. An average season has 10 - 11 named storms, 6 hurricanes, and 2 intense hurricanes. The new forecast calls for a near-average chance of a major hurricane hitting the U.S., both along the East Coast (40% chance, 31% chance is average) and the Gulf Coast (40% chance, 30% chance is average). The Caribbean is also forecast to have an average risk of a major hurricane.

The forecasters cited several reasons for an above-average season:

1) "Warm sea surface temperatures are likely to continue being present in the tropical and North Atlantic during 2010, due to the fact that we are in a positive phase of the Atlantic Multidecadal Oscillation (AMO) (e.g., a strong phase of the Atlantic thermohaline circulation)".

2) Hurricane activity in the Atlantic is lowest during El Niño years and highest during La Niña or neutral years. The CSU team notes that while we are currently experiencing moderate to strong El Niño conditions, it is very rare for an El Niño to last through two consecutive hurricane seasons: "Seven out of the last thirty-five years in an active era (20%) were classified as warm ENSO events. None of the past seven events had El Niño conditions persist through the second year, and every event except for 1951-1952 had an increase in tropical cyclone activity during the second year. It should be noted that an active era and the absence of El Niño does not guarantee an active season, as both 1952 and 2007 experienced near-average net tropical cyclone activity."

How accurate are the December forecasts?

The CSU real-time December forecasts have not shown any skill over the period 1992 - 2007, so we should view the latest forecast as an experimental research product. In 2008, CSU junked the old December scheme and came up with a new one. This year's December forecast uses the same formula as last year's December forecast, which did reasonably well predicting the 2009 hurricane season. However, we new scheme will need to run for 5+ years before we can get an idea of whether or not it has any skill.


Figure 1. Forecasts of El Niño conditions by 20 computer models, made in November. The longest range forecasts for July-August-September (JAS) at the right side of the image show that most of these models are predicting an end to El Niño by then. El Niño conditions are defined as occurring when the average sea surface temperature in the Equatorial Pacific off the coast of South America rises above 0.5°C (top red line). Image credit: Columbia University.



2010 Atlantic hurricane season forecast from Tropical Storm Risk, Inc.

The British private forecasting firm Tropical Storm Risk, Inc. (TSR), issued their 2010 Atlantic hurricane season forecast on Monday. They are also calling for an active year: 13.9 named storms, 7.4 hurricanes, and 3.4 intense hurricanes. TSR predicts a 62% chance of an above-average hurricane season, 24% chance of a near-normal season, and only a 14% chance of a below normal season.

I like how TSR puts their skill level right next to the forecast numbers: 5% skill above chance at forecasting the number of named storms, 8% skill for hurricanes, and 14% 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.

[Derek Ortt]

except the models are keeping the el nino around through next season. It is either borderline neutral/el nino or ful fledged el nino according to the chart posted above

[cycloneye]

IMO,my best analog year that will match what 2010 may have is 1998.The season that year started late (Early August with Alex) due to the decaying strong El Nino of 1997.The same is expected as a decaying moderate El Nino will linger from late spring to early summer.

[Derek Ortt]

However, that year rapidly transitioned to la nina. None of the models are showing that at all

[JonathanBelles]

I have a VERY hard time seeing a forecast being made for an above normal hurricane season. Last I saw El Nino was intensifying or staying steady. I dont see it turning back to neutral anytime soon. I would expect a very average hurricane season in 2010, possibly slightly below average.

[MGC]

It all depends on how long El Nino hangs on. If it lingers into the heart of the season than the numbers could be like this year. I doubt the El Nino hangs on that long though. I'm thinking we will have neutral condition around the start of the season......MGC

[Ptarmigan]

2003 and 2007 were not good for Texas. 2004 was a Modiki El Nino.

[jinftl]

I do expect that the overall consensus for next season's numbers on this board will be based primarily on the experience of the past season. This leaves alot of opportunity for underguessing. People were 'burned' by overguessing last season....there will be a knee-jerk reaction in 2010 to that.

It will all come down to whether we are talking about a peak season (A-S-O) in the grips of an ongoing el nino....or a peak season coming out of an el nino and transitioning into enso neutral. Either case, I don't see 2010 being as 'dull' as 2009 in terms of ACE.

[Blown Away]

Luis,
Was there an El Nino event before all the 2010 analog years?