Look at those Atlantic Anomalies

[cycloneye]

I dont want to say it loud,but the last time I saw these kind of anomalies was in January,2005.

[Coredesat]

The anomalies aren't as bad now as they were last month, when there were large areas of +2C and higher in the north Atlantic.

[cycloneye]

The anomalies aren't as bad now as they were last month, when there were large areas of +2C and higher in the north Atlantic.

Agree,but still they are up there.

[Ed Mahmoud]

I think we are in the warm cycle of the Atlantic Multidecadal Oscillation.


Maybe 2008 will be a busy season (see this thread I started) as Joe Bastardi claims (and it is working for him so far) that this winter is very similar to 1949-1950, and that was a very active season, with multiple Florida hits, including a Cat 3 into Miami

[Ptarmigan]

Since it is forecasted that we will be in Neutral ENSO by this summer, this season could be very active again, well not like 2005. Something like 1950 or 2004.

[MiamiensisWx]

Several interesting studies (including this one) have suggested that the NAO (North Atlantic Oscillation) influences North Atlantic and polar SSTA. For example, the NAO was generally positive when cooler SSTA were present in the polar regions off Greenland. Conversely, SSTA were warmer further south in the North Atlantic (i.e. British Isles to Bermuda) and tropics. This regime is similar to the current configuration. Although the AMO and ENSO state may influence SSTA in the North Atlantic, I think it does not make a significant difference for the 2008 Atlantic TC season.

Another sign is more ominous. The current La Nina is a borderline moderate/strong event. Some signs indicate that this event may be a multi-year deal that is similar to the 1998-1999 La Nina. Many multi-year La Ninas featured big hurricane seasons, including 1893, 1909, 1950, 1954 and 1999. The ratio of major hurricanes vs. total NS was quite high during these years, although many storms were likely overestimated in 1950 (with the possible exceptions of King and Easy). Several of these seasons experienced multiple TC strikes on the United States, especially in terms of hurricanes. 1954 featured three intense hurricanes (Carol/Cat 3, Edna/Cat 3, and Hazel/Cat 4) on the East Coast, and Hispaniola was seriously affected by Hazel. Obviously, there were five Category 4 hurricanes during the destructive 1999 season, including Bret (Cat 3 in TX), Cindy, Gert, Floyd (devastating in the Bahamas and East Coast), and "wrong way" Lenny (adversely affected the NE Caribbean).

I would focus on the ENSO state instead of North Atlantic SSTA.

Edited: I corrected 1955 to 1954.

[Ptarmigan]

Several interesting studies (including this one) have suggested that the NAO (North Atlantic Oscillation) influences North Atlantic and polar SSTA. For example, the NAO was generally positive when cooler SSTA were present in the polar regions off Greenland. Conversely, SSTA were warmer further south in the North Atlantic (i.e. British Isles to Bermuda) and tropics. This regime is similar to the current configuration. Although the AMO and ENSO state may influence SSTA in the North Atlantic, I think it does not make a significant difference for the 2008 Atlantic TC season.

Another sign is more ominous. The current La Nina is a borderline moderate/strong event. Some signs indicate that this event may be a multi-year deal that is similar to the 1998-1999 La Nina. Many multi-year La Ninas featured big hurricane seasons, including 1893, 1909, 1950, 1955, and 1999. The ratio of major hurricanes vs. total NS was quite high during these years, although many storms were likely overestimated in 1950 (with the possible exceptions of King and Easy). Several of these seasons experienced multiple TC strikes on the United States, especially in terms of hurricanes. 1955 featured three intense hurricanes (Carol/Cat 3, Edna/Cat 3, and Hazel/Cat 4) on the East Coast, and Hispaniola was seriously affected by Hazel. Obviously, there were five Category 4 hurricanes during the destructive 1999 season, including Bret (Cat 3 in TX), Cindy, Gert, Floyd (devastating in the Bahamas and East Coast), and "wrong way" Lenny (adversely affected the NE Caribbean).

I would focus on the ENSO state instead of North Atlantic SSTA.

I remember in May of 1998, it was still El Nino, but quite warm and dry. Almost no rain fell that time. I thought that was rather strange because El Nino means it is cooler and wetter for SE Texas. Yes, El Nino had been fading by than. The recent La Nina lasted from late 1998 to early 2000. Kinda weird that La Nina happened right after the strongest El Nino recorded. The 1998 season was active with 14 storms, including Georges and Mitch. I also found that the AMO was quite high in 1998.

I know in 1983, we also had a strong El Nino, which became neutral in the end of 1983. It was a quiet hurricane season for ATL. I read the reason for that was because of strong windsheer and El Nino. Of couse the AMO was in a cooler phase that time.

[hurricanetrack]

These are good observations and ones that we will need to watch closely over the coming months. There was a time a few weeks ago when this map looked even warmer- then it cooled a lot in many areas- now we are back to some pretty overwhelming anomalies to be sure.

I have done some looking in to the La Nina as well and it is really one of the stronger ones of the past 100 years. I think it is interesting to see comparisons to the 50s La Ninas- could be that we see something similar this hurricane season to those??? Only one way to find out- gotta get to June 1 and let it all ride...

[cycloneye]

Several interesting studies (including this one) have suggested that the NAO (North Atlantic Oscillation) influences North Atlantic and polar SSTA. For example, the NAO was generally positive when cooler SSTA were present in the polar regions off Greenland. Conversely, SSTA were warmer further south in the North Atlantic (i.e. British Isles to Bermuda) and tropics. This regime is similar to the current configuration. Although the AMO and ENSO state may influence SSTA in the North Atlantic, I think it does not make a significant difference for the 2008 Atlantic TC season.

Another sign is more ominous. The current La Nina is a borderline moderate/strong event. Some signs indicate that this event may be a multi-year deal that is similar to the 1998-1999 La Nina. Many multi-year La Ninas featured big hurricane seasons, including 1893, 1909, 1950, 1954 and 1999. The ratio of major hurricanes vs. total NS was quite high during these years, although many storms were likely overestimated in 1950 (with the possible exceptions of King and Easy). Several of these seasons experienced multiple TC strikes on the United States, especially in terms of hurricanes. 1954 featured three intense hurricanes (Carol/Cat 3, Edna/Cat 3, and Hazel/Cat 4) on the East Coast, and Hispaniola was seriously affected by Hazel. Obviously, there were five Category 4 hurricanes during the destructive 1999 season, including Bret (Cat 3 in TX), Cindy, Gert, Floyd (devastating in the Bahamas and East Coast), and "wrong way" Lenny (adversely affected the NE Caribbean).

I would focus on the ENSO state instead of North Atlantic SSTA.

Edited: I corrected 1955 to 1954.

Today,Climate Prediction Center came out with the January update and they say moderate La Nina thru the spring with a weaker one after that.We will have to wait and see what evolves in that front in the comming months.

[KWT]

Whats interesting is what happens in the tropics rather then the N.Atlantic IMO. Last summer there was cooler SST's off Africa combined with dust caused cape verde systrems to have a hard time.

[wxman57]

I would suspect that the AMO (SSTs) would govern the positions of trofs/ridges vs. the other way around (NAO affecting SSTs). It's a chicken or the egg discussion, maybe, but I don't think the NAO is controlling the Atlantic Multidecadal Oscillation.

[canegrl04]

I totally expect this season to be closer to 2004 and 2005 The odds are against a 3peat of what we've had lately.And the US will get struck by at least one major 'cane

[KWT]

Note though where the main warm anomalies are again, north of the main cape verde route which actually looks about average to me. However higher SST's would suggest a greater chance of those northerly latitude systems again.

Have to adimt the overall Atlantic is looking decently above average...as you'd expect in a mod/strong La Nina, if they are still present by May/June then it'll be interesting!

[Pedro Fernández]

Note though where the main warm anomalies are again, north of the main cape verde route which actually looks about average to me. However higher SST's would suggest a greater chance of those northerly latitude systems again.

Have to adimt the overall Atlantic is looking decently above average...as you'd expect in a mod/strong La Nina, if they are still present by May/June then it'll be interesting!

Hmmm... I'm not agree with this sentence at all...

Please, see that video from youtube (I'm sure all you know it): http://www.youtube.com/watch?v=PDGnoEnKxkQ

You will see, at the end of the season, last systems developed over cooled waters...

Wind-Shear vs. Warm Waters...

[Tampa Bay Hurricane]

A regime of increased wind shear and/or troughing would
argue for less tropical activity. The jet
stream has pushed episodes of
cold air down while also allowing record
warmth at other times during this past winter.
An active jet would seem to suggest many
troughs and shearing. Impulses of shear carrying
lows would form near the tropics, reducing tropical
activity. Remember that dry air would also reduce activity,
and with SAL the way it is, that would mean fewer storms.
2005 was a rare year, matched only perhaps by 1933.

Now it is important to watch the Sea Surface Temperature
Anomalies, but one thing we have seen in the last several
hurricane seasons is that sea surface temperatures are just
a small part of a much larger equation of conditions needed to
generate tropical systems.

[Javlin]

I am starting to notice something else like 05 season these damn Lows coming up out of the GOM(thats how we got snow on Christnmas day) and the fact that for now alot of High pressure to N that would mean L pressure to the S?It's a wait and see,hell it could flip in 6 months.Kevin

[Tampa Bay Hurricane]

I am starting to notice something else like 05 season these damn Lows coming up out of the GOM(thats how we got snow on Christnmas day) and the fact that for now alot of High pressure to N that would mean L pressure to the S?It's a wait and see,hell it could flip in 6 months.Kevin

Actually I think the lows in the GOM are due to the more active jet stream,
which would Decrease hurricane activity by promoting the formation
of troughs and upper level lows that
cause shear during hurricane season.

More of these winter lows means more shear during hurricane season.
I think shear will keep the number of storms at or below normal this
year, but I am no expert.

[KWT]

I wouldn't think that would be the case though tampa bay beause La Ninas tend to have lower shear on average across the basin...indeed the jet stream is way north so far this winter across the Atlantic ocean and whilst it is strong (the UK has been quite stormy over the last few weeks) it'll weaken a lot as la nina weakens and we head into summer and thermal gradients decrease.

Those SSTA do seem to suggest an active season though is possible.

[Javlin]

That wasn't the actual point TB I was making it more along the line of a pattern that may or may not set up as season approaches.I have noted on here before in the past that as we got snow along the the upper NGOM it seemed like an active GOM season.While not always true 3 out of 4 times it has been and for us to get snow we have to already have the cold temps and the Low comes up from the S to provide the moisture.It's just an ob I have noticed.The two ingredients have not met yet but does the lows in themselves represent a pattern evolving?

[Tampa Bay Hurricane]

That wasn't the actual point TB I was making it more along the line of a pattern that may or may not set up as season approaches.I have noted on here before in the past that as we got snow along the the upper NGOM it seemed like an active GOM season.While not always true 3 out of 4 times it has been and for us to get snow we have to already have the cold temps and the Low comes up from the S to provide the moisture.It's just an ob I have noticed.The two ingredients have not met yet but does the lows in themselves represent a pattern evolving?

Oh sorry.
Yes there might be some correlation, with an active GOM season and the snow.
I guess that nature might be trying to balance it by transferring hurricane
season heat further northwards to balance the previous winter snows, but that
is just my theory, the professional mets might know the connection better.