by

Robert G. Brookens Jr./Barometer Bob

Hurricane Hollow Tropical Weather

This prediction is made for the Weather Enthusiast in mind. It should not, and is not an Official Forecast that should be used for the use to Protect your LIFE and PROPERTY. This prediction, as well as the Weekly Weather predictions that I release, are based upon my knowledge of the weather! The Atlantic Hurricane Basin is one that has the potential to make an impact on a large area of the Coastal United States, Caribbean Islands, and Central America. Due to the potential of the Threat to Life and Property, from Hurricanes in the Atlantic Basin, This is my Atlantic Hurricane prediction for the 2006 Hurricane Season.

INTRODUCTION

This Atlantic Hurricane Season 2006, we will be looking for annual and seasonal indicators, based on averages of 10 named storms, 6 hurricanes, 3 major hurricanes(100%) respectively, which is historically shown in data through the world wide web, and also known as being a percentage that is followed by many forecasters as well as researchers. I will show a tendency, as I have in the past five seasonal predictions, that this seasons potential of being above normal once again, and has an extreme chance of being yet another hurricane season that will have a large impact on life and property if we aren't prepared. This is in part responsible to a combination of global influences where professional meteorological researchers and forecasters are doing research. The Pacific Decadel Oscillation (PDO), ENSO (El Nino/La Nina), as well as the combination of the North Atlantic Oscillation (NAO), The Atlantic Thermohaline Circulation (ATC). These oscillations are responsible for a number of weather phenomenons that occur across the globe, but directly affect the Western Hemispheric Weather patterns where the Atlantic Hurricane Basin is located. We can see this by looking at history when we had periods of above and below normal activity, such as the 1930's - early 1960's (above average) and the latter 1960's to the early 1990's (below average). Even though, some may point out that there are a number of years within these periods that had below or above average numbers of Tropical Storms and Hurricanes, but during those years other indicators added or reduced the number such as El Nino and La Nina (ENSO) periods, wet and dry periods of the African Sahel Rainfall, Atlantic Thermohaline Circulation, affects of Sea Surface Temperatures, Quasi-Biennial Oscillation (QBO), which can if in a favorable direction enhance Tropical Cyclogenesis. The PDO (Pacific Decadal Oscillation), which can influence stronger then normal Kelvin Waves. Of these and other indicators, We can see an above average number of Tropical Cyclone development this coming Atlantic Hurricane Season 2006.

Again, this is a prediction, and should not be used to evaluate whether or not you should have a plan and an evacuation route for the 2006 Hurricane Season! If you live within 100 miles of a coastal plain, you should be aware of the dangers that landfalling hurricanes can affect your area. From high winds to inland flooding, hurricanes as we have seen the past few years (2000 - 2005) have had a long reaching affects well inland. Awareness is your key to being prepared! So please, have a plan, and be ready to initiate it when the time comes!

Prediction Parameters:

Global Influences on Tropical Cyclogenesis!

El Nino/La Nina Forecast (ENSO)

As I predicted last April 2005, we would be in a neutral ENSO through and a weak negative ENSO as the 2005 Hurricane Season ended, and into November and the 2005/2006 winter we would begin to see a La Nina developing. Well, here we are. This La Nina began to develop November 2005, and is peaking in it's influences March/April 2006. The problem with a weak La Nina peaking in March/April, and the given forecasts by the CPC indicate that La Nina will persist into the beginning of the 2006 Hurricane Season, and should continue into July/August before we see neutral ENSO conditions begin to take place.

This once again, will enhance the peak periods from August to October 2006 for Tropical Cyclogenesis. We have been looking at past seasons where we had a La Nina during the winter/spring moving into the first half of the Atlantic Hurricane Season. This is very similar to 2001 when we were in a weak La Nina episode. Other years of continuing weak La Nina episodes from Spring to Summer months include: 1950, 1954-1956, 1961, 1964, 1970-71, 1973-75, 1985, 1989, 1998-2000. During the 2000-2005 period we saw weak neutral, except for 2002 and 2004 which we saw a moderate El Nino(2002) and weak El Nino(2004). The period during the 1950's and early 1960's we saw La Nina and neutral ENSO conditions as seen in CPC ENSO Years, except for 1957-58, 1963, 1965.

This shows a strong indication that we are in an identical period of the 1950's:

Looking at years that were Neutral following a La Nina shows that there was an above active season. Prolonged La Nina or Neutral years we saw a average (10) or below average season. Based on this, we saw a Neutral ENSO during the 2005 Hurricane Season, leading into a weak La Nina for the 2006 Hurricane Season. Even though, we saw 27 named storms during the 2006 Hurricane Season, the 2006 season will be well above average, but not as active as the 2005 season.

Sea Surface Temperatures (SST) in the Atlantic Hurricane Basin:

Sea Surface Temperatures are basically one of the main fuels to allow strengthening of a Tropical Cyclone. If SST's are not at least 78 degrees or warmer, then Tropical Cyclogenesis is not favorable to occur. I have broken down each region of the Atlantic Hurricane Basin to reflect the potential differences of Sea Surface Temperatures for each region. We could however see the transition of Sub-Tropical Development with cooler SST's, Stalled Frontal Boundaries, but this tends to be limited to those incidents and months where SST's are either on the warming or cooling trend. In other words, early or late in the season.

The West Atlantic (35N/23N-60W to the Eastern Seaboard):

We saw the Gulf Stream Current off the Southeast Coast of the United States forecast to be below average during the 2006 winter and spring months (Jan-May). This is an area of Ocean Current that flows adjacent to the Eastern Seaboard which originates through the Florida Straits from the Southeast Gulf of Mexico (Florida Current), and where the Antilles Current curves north and westward hence the name, The Gulf Stream. This is based on SST's taken by observations by buoys and ships during the winter months of 2005-2006. We also have seen the persistent troughs exiting the Eastern Seaboard during this past winter 2006. This has led to average SST's along the Eastern Seaboard of the United States. We could however watch to see if we turn to a more above average SST's from Florida north to Cape Hatteras during the mean months of the 2006 hurricane season. This will be caused by the direct solar heating of the oceanic surface, also known as Diurnal Solar Heating. This will also assist for above average SST's of the North Atlantic Currents, which directly affects the Atlantic Thermohaline Circulation, and Temperatures and Rainfall over Europe . So considering these influences, we should see average SST's in the Western Atlantic Region, as we did in 1995 and 2004, 2005, With a La Nina in place, we could see SST's approaching above average across the entire Atlantic Hurricane Basin.
Curriently (March/April) we see above avergare SST's across the entire Tropical and Subtropical Atlantic. This is especially seen along the east Coast of Florida and through the Bahama's. If this trend continues, we will be 0.05C - 1.0C above average for the 2006 Hurricane Season.
To add, research that has been performed and released (March 2006) by Georgia Tech mentions that the current state of midlevel water temperatures in some areas would not allow for cold water upwelling when a developing or strong tropical cyclone is to pass over these areas. This would enhance strengthening, and we would have a higher chance of seeing numerous intense hurricane development during the 2006 hurricane season.

The Gulf of Mexico:

During the winter months of 2005/2006 we saw average air temperatures due to the weak La Nina conditions develop. This led to average SST's in the North Central, Northwestern, Northeastern Gulf of Mexico. Mostly, this occurred near the Central Gulf Coast and extended south to about 24N and from 85N - 95N respectively, known as the Gulf Loop. In time, we will continue to see the SST's increase on an average or slightly above average by June and July 2006, and continue to create areas of above average SST's in areas of the GOM through the rest of the season. This we saw last season, it can change dramatically over a period of a couple of weeks. I forecast average SST's in the Gulf of Mexico, with larger areas of above average SST's in the GOM.

In the Caribbean Sea:

We should continue to see above average SST's being, that most of the 2005-2006 winter the lack of strong cold fronts to sweep through the Caribbean Basin allowing for warmer air temperatures. This leads to warmer SST's and lack of cloud cover due to the lack of troughs and sustained high pressure over the Caribbean and Western Atlantic allows for warming during daytime heating periods. Again, this has a large implication of the potential strength and rapid intensification periods we have seen in the past from a Tropical System in the Caribbean. If other factors are favorable, lack of a TUTT, then we will continue to see substantial development in the Caribbean Sea. I forecast above average SST's again this season in the Caribbean Sea.

In the Tropical Atlantic, from 60W eastward to the African Coast; Including the MDR (Mean Development Region):

I predict average and large areas of slightly above average SST's throughout the Atlantic Hurricane Basin for 2006 Hurricane Season. This is due to the above normal SST's of the Gulf Stream and the North Atlantic Current, which in seasonal fluctuations should allow for the SST's of the Tropical Atlantic to be at or slightly above average. There has been little research done on the SST's in the Eastern Atlantic, especially along the African Coastline. We saw average and slightly below average SST's in the Eastern and Central Tropical Atlantic in 2004, and warmer SST's in 2005. The average SST's is forecast this year. But, with this area between 10-20N/30-45W at average we could expect development of an organized Tropical System and strengthen as it reaches even warmer above average and more favorable SST's, as we move towards the peak of the Hurricane Season when this area will be favorable for development.

Surface Air Temperatures (SAT)

With a number of active parameters that aid to warmer air temperatures, SST's, Westerly QBO, a positive ATC, and a weaker Atlantic Ridge due to a neutral or negative NAO, we should anticipate slightly above average SAT's across the Atlantic Hurricane Basin during the months of late July, August, September and the early portion of October. This we will see in surface observations throughout the basin that is reported on a regular basis from a number of sources such as Meteorological Departments, Ships, and Buoys. An average of 1-3 degrees in areas above average wouldn't be uncommon with the many favorable indicators for this 2006 season. The winter of 2005/2006 was one of the warmest winters on record for the United States and Canada. This can have even further implications not only on SST's, but on SAT's.

North Atlantic Oscillation (NAO)

We currently have a negative NAO, but the forecasts from the United Kingdom Meteorological Office does not update till May 2006, so we take into consideration of the actual weather at the time of this posting on how we can derive the forecast for the NAO. Northern Europe is about average in precipitation and below average temperatures, as in Southern Europe, it's slightly dryer and cooler. Record cold for areas of the Eastern Hemisphere We also have seen warmer temperatures and more precipitation in Northern United States mainly in the Midwest and Northeastern United States the past winter, and currently. This seems to be ongoing.
So with the potential of a negative but near neutral NAO, we should continue to see indications of a weak neutral to negative North Atlantic Oscillation to continue due to the continued weak La Nina. But could we conitue to see a negative NAO if La Nina continues? Yes we could. So we should continue to see the affects a negative NAO, with its influences as we go through the 2006 Hurricane Season. Does this have any affect on the Tropical Atlantic? Yes, it subsequently affects other indicators such as the Atlantic Thermohaline Circulation (ATC). The ATC has been active past years, and it's expected to remain active as it has during the active seasons of the past decade. With a weaker Atlantic Ridge, which occurs with a neutral or negative NAO, we can watch for the SST's in the Eastern Atlantic to be average, this year, as we have seen the years of active Tropical Cyclogenesis in the 1990's. Calmer winds in the Eastern Atlantic, and thus allowing for slightly warmer SST's in the Eastern Tropical Atlantic. This will allow for warmer conditions to feed into and through the entire Atlantic Hurricane Basin by the peak of the season. This all reflects towards warmer conditions in the MDR for the 2006 season. This is including the average SST's in the SubTropical Atlantic.

Pacific Decadal Oscillation (PDO):

Based on observations and information on the World Wide Web we are currently in a weak negative PDO, and this should continue through the 2006 Hurricane Season. A positive (Warm Phase) PDO is also an indicator of a ENSO/El Nino, and a weakening PDO a precursor to a neutral ENSO or La Nina event. Causes for the fluctuation of the PDO are unknown, but research is ongoing into this oscillation, and the prediction of this oscillation will allow for more skillful long term predictions in time. But, that it does have a relationship between a El Nino and a La Nina event is shown in the PDO Index http://www.atmos.washington.edu/~mantua/TABLES2.html It shows that currently and in the past when we have been in a weakening El Nino (positive PDO), or a neutral phase of ENSO, and when the values move towards a negative value (negative PDO), we are more likely to have a La Nina event in the near future. So this is an indicator that is not entirely without bias, it still shows an indication of what may be to come in the climate variability relating to the Atlantic. The PDO can also enhance Kelvin Waves. The question is, Will this allow for the La Nina to weaken sooner or to linger a little bit longer?

Hurricane Basin Regional Forecasts:

African Sahel Rainfall:

I predict a wet African Sahel Rainfall season. Based on the forecasting a westerly QBO, a weak La Nina, we should see a above average Sahel Rainfall season during this period. It will not however, be of record proportions. This is due to the near neutral and slightly negative or positive climatologically changes that are occurring or have occurred recently including ENSO, NAO, that are ongoing at the posting of this forecast.

Quasi-Biennial Oscillation (QBO) Index:

This will be a westerly, favorable direction this season. With the weak La Nina, and the easterly QBO that we had during July of 2005. A westerly phase of the QBO shows favorable conditions for development of Tropical Cyclogenesis in the Tropics. This is how the QBO affects Tropical Cyclogenesis are as follows:
1) Atlantic Tropical Cyclogenesis is inhibited during easterly phases of the QBO due to enhanced lower stratospheric winds and increased upper-troposphere-lower-stratosphere wind shear; Which we saw the last two years.
2) For slow moving systems, the west phase of the QBO has a slower relative wind than does the east phase. This allows for greater coupling between the lower stratosphere and the troposphere allowing for a more favorable environment for development.
So a Westerly QBO is in favor due to the fact we had a Easterly QBO last season. And weaker easterly winds due to the weaker Atlantic Ridge. This indicates a more active Cape Verde Hurricane Season then we saw in 2005.
To learn more about the correlation of Tropical Cyclogenesis and the QBO go to: http://typhoon.atmos.colostate/Includes/Documents/Publications/gray1984-1.pdf

Vertical Sheer in the Mean Development Region (MDR):

With a forecast Westerly QBO, and a weaker Atlantic Ridge we should see a lessened shear environment for the MDR overall. A weak La Nina, with a weak negative ENSO possibly developing later in the season, should make this area more favorable for tropical cyclogenesis then 2005. This area should be favorable for development of an organized Tropical System that originates from the Cape Verde Island Region.

Barometric Pressures:

The barometric pressures over the Atlantic, and Africa have a direct relationship to development and track of Tropical Cyclones. This is known by looking at a strong Atlantic Ridge, and the slower or lack of development of Tropical Cyclones because of shear, the forward speed of the Tropical Wave is too fast, and the separation of the developing area of low pressure and the convective cloud cover that would allow for further development. If we have a Strong Azores High, what is to happen? We see less development in the MDR due to Tropical Disturbances moving westward too rapidly and strong subsidence. A weak Atlantic Ridge, which is being forecast for 2006, will allow for more coupling of the stratospheric and tropospheric winds, and a slower westward movement, further allowing for more organization and further development. This combined with a favorable QBO; we should see a more favorable environment in the Tropical Atlantic, including the MDR then recent years. Similar to 1995 and 2004. We will also see below average barometric pressures over Africa. This will also allow for a more favorable environment for a Tropical Wave to survive as it exits the continent into the Eastern Tropical Atlantic. So with average BP's over Africa, and a weaker Atlantic Ridge giving lower BP's then the prior seasons, less subsidence in the MDR.

Atlantic Ridge

Azores High - Bermuda High:

The Azores High is located in the Eastern Atlantic, also known as the Atlantic Ridge. This is a permanent feature in the Atlantic. Though it does have a tendency to fluctuate, and relocate based on seasonal positions, we can base a forecast on the strength of the Azores High from a number of indicators that are in place during the development of this forecast. Based on the information of a negative NAO, we will have a weaker Atlantic Ridge. The Bermuda High is located in the Western Atlantic, and is normally situated near or over Bermuda, hence the name. This is a semi-permanent feature, meaning it develops and weakens and dissipates, and redevelops, or is replaced by a High Pressure that moves off the East Coast of the United States and becomes stationary. It's also referred to a westward extension of the Azores High. When the Azores is in a weaker state, we have a more consistent Bermuda High Pressure. So this season, we should see a more stable Bermuda High, especially during the mid term of the season (July - October). Similar to 1995 and 2004.

Tropical Upper Tropospheric Trough (TUTT):

This is a feature that is a semi stationary trough that is located from Southwest to Northeast in the Caribbean Sea, and Western Atlantic. Between 10-25N and 55-70W respectively. This normally develops in late May and June and continues through till about October. This feature creates shear, and shear is not favorable to the development of Tropical Cyclones. We have seen the past few years go from a very strong TUTT to last three years almost non-existent. During the first portions of the 2005 hurricane season we had a easterly QBO. For 2006, again, I forecast a weak TUTT to begin the season, but dissipating as we move into the mean of the season. This is due to a westerly QBO, as we saw in 2004 a weaker Atlantic Ridge, where a strong Atlantic Ridge allows for stronger winds at different levels, which should not be the case this season.

These are some of the key ingredients that I pointed out throughout the forecast. The regions of the Eastern and Western Atlantic, Caribbean Sea, and the Gulf of Mexico are the four regions that I will be focused on.

The Eastern Atlantic Ocean, between 17W-40W / 5N-30N :

Will be more favorable for development of Tropical Cyclones then 2005, more so in the Cape Verde Region. Average to slightly above average SST's, a weaker Atlantic Ridge, and continual strong convective patterns (Tropical Waves) emerging off the African Coast to allow for further development of Tropical Cyclones.
The Eastern Atlantic will be more favorable for Tropical Cyclone Development then the recent seasons (2001-2002, 2005), but, possibly as favorable as 1995 and 2004.

The Western Atlantic, this includes the area of the Bahamas and Bermuda 40W-61W / 20N-35N.

This area will be favorable due to the warmer SST's and weaker Atlantic Ridge. This area we should see once again Sub-Tropical Development as we have seen the past seasons.

Bahama Islands Area:

With the Bermuda High in a more predominant state due to the weaker Azores High, this area will be active once again while the Bermuda High is moderately strong. But due to the passage of weak areas of disturbed weather from the Gulf of Mexico, and or stalled frontal boundaries, we should see development from this region during the season. We could also have systems move through this area from the Tropical Atlantic or Caribbean due to long track Tropical Waves/Cyclones during the peak period of the season of late August to Early October.
The Western Atlantic will be favorable for Tropical Cyclone Development.

Caribbean Sea:

With a weak TUTT early in the season, lower SLPA, above normal SST's, development is highly favorable for development in the Caribbean Sea. What we will be watching for though is a Tropical System approaching the Caribbean from the Tropical Atlantic, and how it is affected by the TUTT early in teh season. After the passage of the Tropical System through the TUTT, further organization and development would be expected.
The Caribbean Sea is very favorable to Tropical Cyclone development. We saw in 2004, 2005. Development in the Eastern Caribbean, though this is rare, and is possible again in 2006.

The Gulf of Mexico(GOM):

The GOM is surrounded by landmass, and any development is sure to create a land falling Tropical Cyclone. We have seen this late Winter and early Spring development of low pressures along the Gulf of Mexico (GOM) coast, and I don't see any reason why it won't continue. Plus, the fact of having Tropical Waves/Depressions/Storms/Hurricanes, entering the GOM from the Caribbean Sea and through the Florida Straits, we see the potential of a major land falling Tropical Cyclone develop/strengthen from this region as we saw in 2004 and 2005.
The Gulf of Mexico is very favorable for Tropical Cyclone Development.

The main consensus is to be prepared, to protect your LIFE, and PROPERTY!!!

5 Major Hurricanes of Category 3,4,5

The United States has a 80% chance of a landfalling Tropical Cyclone this season. Of this Florida, the Caribbean Islands, and the Gulf Coastal areas has a high chance to be affected by a Tropical Cyclone combined! On top of this, areas north of Cape Hatteras should be very concerned and be aware of the tropics for the 2006 Hurricane Season. Reason, the Bermuda High being substantial once again, wamer SST's along the Eastern Seaboard could allow for a landfall north of Cape Hatteras.

The potential of 6 threats from Tropical Cyclones to the State of Florida. Of these, 2 from the Atlantic, 2 from the Gulf of Mexico, and 2 from the Caribbean.

I do believe that we will see an above average Hurricane Season 2006, and the role of La Nina being the mitigating factor.

Thank you for taking your time to read my prediction. As you will find, being I am not a meteorologist, I spend my spare time aside from work and family, to learn and help people learn more about the weather, and to be better prepared!

Awareness is Key to Preparedness!

Please remember this is a view from a Weather Enthusiast!! I am in no way a Professional Meteorologist, and this is a layman's point of view.
Thank You and I hope we all have a SAFE and QUIET Hurricane Season 2006!
Please visit my websites for more information on Tropical Cyclones!

Robert "Barometer Bob" Brookens