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18z GFS E-pac crossover
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18z GFS E-pac crossover
The 18z GFS continues to depict energy coming from the EPAC and crossing over Central America. At that time it appears to close of an LLC over the W Carribean and treks it towards Cuba/Fl straits. Interesting late week ahead considering it's mid May. As they say the trend is your friend so future runs may become very entertaining if the trend persists.
http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_126l.gif
http://www.nco.ncep.noaa.gov/pmb/nwprod ... p_126l.gif
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feederband
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cyclonaut
Just remember all:
One storm now in May or June might get us all excited but it means that July, August, September and October will be DEAD.
Remember your blocking theory. I, for one, hope to god that no storms form now because that means 2005 will be a huge dud.
Of course, I want to see hurricanes form and then turn away from land but it is fun to track them first and then see them turn away.
Having none at all is not good.
One storm now in May or June might get us all excited but it means that July, August, September and October will be DEAD.
Remember your blocking theory. I, for one, hope to god that no storms form now because that means 2005 will be a huge dud.
Of course, I want to see hurricanes form and then turn away from land but it is fun to track them first and then see them turn away.
Having none at all is not good.
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cyclonaut
jason0509 wrote:Just remember all:
One storm now in May or June might get us all excited but it means that July, August, September and October will be DEAD.
Remember your blocking theory. I, for one, hope to god that no storms form now because that means 2005 will be a huge dud.
Of course, I want to see hurricanes form and then turn away from land but it is fun to track them first and then see them turn away.
Having none at all is not good.
According to many in the field of meteorology Aug,Sept & Oct will be anything but dead.
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Don Sutherland's post and Senorpepr. Early season storm formation indicates a blocking pattern may develop later in the year and put a damper on later storm formation. The post is below:
jason0509 wrote:jason0509 wrote:Since 1950 when daily records have been available for the North Atlantic Oscillation (NAO), there have been 24 years that have seen the NAO fall to -1.500 or below in June and 25 such blocking episodes. The lowest-ever figure for the NAO in June was -3.146, which was established on June 12, 1971.
If one examines tropical activity in these 24 years against tropical activity in the remaining 31 years, one finds that the development of strong blocking regimes tends to inhibit tropical activity.
Percentage of Years with 1 or More June Tropical Storms/Hurricanes:
∙ Strong blocking regimes: 9/24 (38%) years
∙ No strong blocking regimes: 17/31 (55%) years
Average Number of June Tropical Storms/Hurricanes:
∙ Strong blocking regimes: 0.42
∙ No strong blocking regimes: 0.71
In years in which a strong blocking regime developed, just 4/24 (17%) saw a tropical storm or hurricane develop during that blocking regime. In 1998, there were two such blocking regimes. No tropical storms/hurricanes developed in June 1998.
If one factors in strongly positive NAO regimes (+2.000 or above), months in which strong blocks and strongly positive NAO regimes occurred, had about normal tropical activity:
∙ 4/8 (50%) years saw 1 or more tropical storms/hurricanes
∙ 0.50 tropical storms/hurricanes per year
Thus, the years with the lowest tropical storm/hurricane activity were those that experienced strong blocks without any strongly positive NAO regimes. In those years, 5/16 (31%) saw a June tropical storm or hurricane. The average number of tropical storms/hurricanes for June came to 0.38 in such years.
If that's wrong, please correct me.
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Couple of things here...
1. The last time I remember something springing up and threatening a EPAC to ATL crossover was...gasp...1997. For a weak low level system to cross that way means that the winds down there are not moving in the same general direction they usually do (they should be moving e to w).
2. It rarely if ever happens. If someone with more time could take a look I wonder what the connection is between the very few times this has happened and Nino years. I bet there is a strong statistical corellation.
3. Remember it's the GFS. There is a reason the GFS is not so much a good model for tropical cyclogenesis. I realize they have and will be putting in some upgrades this season but it has always had a bias for stirring up a circulation from convective leftovers in the model.
4. Remember it's the GFS.
I believe the UKMET had also been toying with some west to east moving system for development a little further to the west a couple of days ago so that does mean something.
Looks like the secondary low back at 100W is what the GFS is seeing and then the model takes them both back to the east and does some phasing late in the week once the model resolution lowers some.
To me the big story is westerlies at 950MB from about 100W developing/maintaining in the next week. Going to have to watch the eastern Pacific very closely through the end of the month. Right now anoms near the equator east of 100W are fairly cool but up near 10N they are running +1 across the board.
MW
1. The last time I remember something springing up and threatening a EPAC to ATL crossover was...gasp...1997. For a weak low level system to cross that way means that the winds down there are not moving in the same general direction they usually do (they should be moving e to w).
2. It rarely if ever happens. If someone with more time could take a look I wonder what the connection is between the very few times this has happened and Nino years. I bet there is a strong statistical corellation.
3. Remember it's the GFS. There is a reason the GFS is not so much a good model for tropical cyclogenesis. I realize they have and will be putting in some upgrades this season but it has always had a bias for stirring up a circulation from convective leftovers in the model.
4. Remember it's the GFS.
I believe the UKMET had also been toying with some west to east moving system for development a little further to the west a couple of days ago so that does mean something.
Looks like the secondary low back at 100W is what the GFS is seeing and then the model takes them both back to the east and does some phasing late in the week once the model resolution lowers some.
To me the big story is westerlies at 950MB from about 100W developing/maintaining in the next week. Going to have to watch the eastern Pacific very closely through the end of the month. Right now anoms near the equator east of 100W are fairly cool but up near 10N they are running +1 across the board.
MW
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Updating on the twitter now: http://www.twitter.com/@watkinstrack
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HURAKAN
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Allison, 2001, was the last tropical cyclone to form with EPAC origens. Look at the NHC "Tropical Cyclone Reports."
Satellite images and synoptic data indicate that Allison originated from a tropical wave that moved off the west coast of Africa on 21 May. The wave tracked westward at about 15 kt across the tropical Atlantic with little associated convection before moving inland over the northern part of South America on 26 May. It emerged over the southwestern Caribbean Sea on 29 May. The wave moved westward into the eastern North Pacific Ocean on 1 June, then slowed down over the Gulf of Tehuantepec. On 2 June, the wave produced a low-level cyclonic circulation centered about 200 n mi south-southeast of Salina Cruz, Mexico.
On 3 June, low- to mid-level southwesterly flow in the southeast quadrant of the Mexican thermal low moved the broad cyclonic circulation inland over extreme southeastern Mexico and western Guatemala. The low-level circulation weakened and became ill-defined after moving inland, whereas the strong mid-level circulation remained intact and tracked northeastward over the southern Yucatan Peninsula early on the 4th. By 0000 UTC 5 June, the mid-level circulation had moved northwestward into the Bay of Campeche of the Gulf of Mexico. Deep convection developed along the western (cyclonic-shear) side of a 30 to 40 kt low-level jet whose axis extended north-northwestward from Merida, Mexico to the Texas-Louisiana border. The deep convection persisted during the night of the 5th and eventually moved north-northwestward around an upper-level cold low centered over south Texas. The difluent eastern semicircle of the upper-level low acted to enhance the development of deep convection.
By 1200 UTC on the 5th, satellite imagery and surface observations suggest that the mid-level circulation developed downward and became Tropical Storm Allison about 120 n mi south of Galveston, TX (see Figure 1 - Figure 3 and Table 1). The cold-core nature of the upper low detected in 0000 and 1200 UTC 5 June upper-air data suggests, however, that this system possessed some subtropical characteristics.
Satellite images and synoptic data indicate that Allison originated from a tropical wave that moved off the west coast of Africa on 21 May. The wave tracked westward at about 15 kt across the tropical Atlantic with little associated convection before moving inland over the northern part of South America on 26 May. It emerged over the southwestern Caribbean Sea on 29 May. The wave moved westward into the eastern North Pacific Ocean on 1 June, then slowed down over the Gulf of Tehuantepec. On 2 June, the wave produced a low-level cyclonic circulation centered about 200 n mi south-southeast of Salina Cruz, Mexico.
On 3 June, low- to mid-level southwesterly flow in the southeast quadrant of the Mexican thermal low moved the broad cyclonic circulation inland over extreme southeastern Mexico and western Guatemala. The low-level circulation weakened and became ill-defined after moving inland, whereas the strong mid-level circulation remained intact and tracked northeastward over the southern Yucatan Peninsula early on the 4th. By 0000 UTC 5 June, the mid-level circulation had moved northwestward into the Bay of Campeche of the Gulf of Mexico. Deep convection developed along the western (cyclonic-shear) side of a 30 to 40 kt low-level jet whose axis extended north-northwestward from Merida, Mexico to the Texas-Louisiana border. The deep convection persisted during the night of the 5th and eventually moved north-northwestward around an upper-level cold low centered over south Texas. The difluent eastern semicircle of the upper-level low acted to enhance the development of deep convection.
By 1200 UTC on the 5th, satellite imagery and surface observations suggest that the mid-level circulation developed downward and became Tropical Storm Allison about 120 n mi south of Galveston, TX (see Figure 1 - Figure 3 and Table 1). The cold-core nature of the upper low detected in 0000 and 1200 UTC 5 June upper-air data suggests, however, that this system possessed some subtropical characteristics.
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