
NAO and track of systems in MDR
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cycloneye wrote:Blown Away,you will be very interested to read this discussion about the NAO and the tracks in the Tropical Atlantic as you are always very interested about this:I say that the members in general can learn new things about this theme.
NAO and track of systems in MDR
cycloneye wrote:Blown Away,you will be very interested to read this discussion about the NAO and the tracks in the Tropical Atlantic as you are always very interested about this:I say that the members in general can learn new things about this theme.
NAO and track of systems in MDR
Blown Away wrote:cycloneye wrote:Blown Away,you will be very interested to read this discussion about the NAO and the tracks in the Tropical Atlantic as you are always very interested about this:I say that the members in general can learn new things about this theme.
NAO and track of systems in MDR
Awesome, I'll need to read through a few times to grasp everything. But I read -NAO with La Nina we will typically see the BH positioned more south and west which results in more landfalls. That is why JB had so many storms developing west of 55 and many of those making landfalls. Anything developing east of 55 will likely recurve due to a weak Azores high. Good find!!
Dynamic wrote:Hi! As I can read in this post, the NAO forecast for this hurricane season will be negative? Where can I find the NAO forecast on the Web? Thanks!
Blown Away wrote:Awesome, I'll need to read through a few times to grasp everything. But I read -NAO with La Nina we will typically see the BH positioned more south and west which results in more landfalls. That is why JB had so many storms developing west of 55 and many of those making landfalls. Anything developing east of 55 will likely recurve due to a weak Azores high. Good find!!
Trough split near the east coast next week. A trailing trough coming east will reach the east coast this weekend and split away southeast. With a major area of high pressure building over the lakes and northeast and out into the northwest atlantic, this sets the stage for the threat of the first tropical of subtropical, or both, development of the season.. one east of the Bahamas and the other over the western Caribbean. The northern one is the kind that could be considered subtropical, the southern one the more classic early season tropical version. 5) La Nina base pattern now evident. The warm waters in the Arabian sea and indian ocean and the rapid cooling of the central Pacific mean a stronger than normal trade wind belt is developing over the Pacific and this is conducive to a stronger than normal monsoonal circulation where there really are Monsoons ( asian sub-continent) this also helps out with the African wave train and with the water bath tub warm in the atlantic it means the idea that this could be a big hurricane season has the physical realities of the pattern to back it up. The MJO upward motion patterns get distorted so that the prime area of the wave is mostly African, the western hemisphere, and Indian Ocean as far as upward motion goes. This offers the threat of major difference from 06 and 09, when the El nino kept the core of upward motion in the Pacific basin, 2008, when it was almost perfect for timing so there were up down periods, and 2007 when the atlantic was not as warm as it is now. Interestingly enough, the year the pattern resembles most closely now is 2005, though a trimming of the extreme option has to be considered. The point is the MJO upward motions considerations may find the 40 day wave "stuck" in areas favorable to western hemisphere development, as opposed to last year when it wasnt
OuterBanker wrote:Cyclone. Quick question. The quote above was from the Accuweather pro site. Is that allowed? I have been real carefull about not doing that.
I don't think it would be improper to post a general summary of JB's thoughts in one's own words on this site.cycloneye wrote:OuterBanker wrote:Cyclone. Quick question. The quote above was from the Accuweather pro site. Is that allowed? I have been real carefull about not doing that.
I dont know if is from that as I found it posted on Weatherunderground site. If that is the case,no more posting of his discussions unless is from the Accuweather free site.
wxman57 wrote:Blown Away wrote:Awesome, I'll need to read through a few times to grasp everything. But I read -NAO with La Nina we will typically see the BH positioned more south and west which results in more landfalls. That is why JB had so many storms developing west of 55 and many of those making landfalls. Anything developing east of 55 will likely recurve due to a weak Azores high. Good find!!
As I posted several times in this thread, a negative NAO occurs when the Icelandic low is positioned farther south and pressures are lower along/off the East U.S. Coast. This results in a weaker Bermuda High that is shifted north and east - not south and west. A weaker Bermuda High means reduced easterly trade winds and less low-level shear in the MDR. It also means less upwelling of cool water and less dry air moving off Africa. All favorable conditions for development in the MDR.
Dynamic wrote:The image below will validate with illustrations the WXMan57 comments above. But I don't understand how a negative NAO conditions will results in more landfalls to the Caribbean and US coast as per JB said. If the Bermuda High is shifted north and east (as per the image below and 57 comments), the hurricanes in the MDR will not follow the border of the high? Under this scenario all the cyclones to the east of the Antilles will like to recurve, that is correct?
http://upload.wikimedia.org/wikipedia/c ... arison.jpg
wxman57 wrote:
A negative NAO results in weaker trade winds, less low-level wind shear, warmer SSTs and less dry air. Conditions are much more favorable for development in the deep tropics. The vast increase in the number of developing storms is the reason for the greater threat. Yes, with a weaker Bermuda High, more storms will recurve farther east, but more will also get through to the Caribbean since more will be developing.
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