The past week has seen an onset of what one
After what has been an extremely slow start to the Atlantic hurricane season things finally seem to be kicking into gear. The usual trend took place for the season though, with the first few storms of the season developing near the CONUS, primarily in the Gulf and Caribbean. This is due to the fact that conditions tend to be more favourable in these areas in the early months while the Eastern part of the Atlantic remains un-conductive for development. The season started off with Hurricane Alex, which was an unusual storm with an extremely low pressure, but winds which were a lot weaker than what would usually be found with those pressures- this was due to a lack of strong ridging and generally lower surround air pressure meaning the gradient of pressure was less and in turn so were the winds. Alex formed in the late days of June, and by the looks of it the Atlantic was in for a busy season as predicted… Or so people thought.
In the period between the A and B named storms there was a tropical depression which showed some promise in early development, but was not able to establish a good core for development and never reached tropical storm strength.
Next up was Tropical Storm Bonnie which formed in late July, it formed from a long tracking tropical wave which passed north of the Caribbean islands and later impacted the state of Florida. The storm remained weak throughout its life with a peak wind speed of 40mph. Bonnie too looked as though it was a sure strong tropical storm heading into very warm SSTs, but was never to be. At one stage the SHIPS intensity guidance forecasted a category 2 hurricane from Bonnie.
A week after Bonnie, eyes were now focused on another wave in the Central Atlantic which would later become Tropical Storm Colin. By now many were using Colin as benchmark for whether the season could redeem itself. Now already the beginning of August it was expected that Colin would encounter favourable conditions and be able to develop. The wave did in fact become Colin and began to look as though it had the chance to become a hurricane in future, but then Colin encountered some hostile conditions and shear combined with forward speed ended up with the LLC speeding ahead of the convection, which was displaced to the east.
By now many had given up hope in the season, claiming that nothing could survive and would somehow be killed off by shear or dry air.
Between the forming of Colin and Danielle there was also a minimal tropical depression which formed in the Gulf of Mexico, but is nothing to write home about, making landfall on the Gulf coast, bringing with it some showers and a breeze.
Long ahead of Danielle’s arrival the models had picked up on her development and the GFS in particular was showing Danielle forming 384 hours out, and what turned out to be in relatively close distance to where she actually formed. Danielle formed from a vigorous African wave which was showing signs of development as soon as it hit the water, it was even labeled as a research invest before it had left Africa and would later become an official invest wave. Danielle took a few days before she finally established a good core and later became a tropical storm and hurricane, though for a period she looked sick with dry air managing to penetrate her core, as could be expected many were calling it her death claiming that no storm could survive the 2010 season. Though just a few hours later Danielle was able to enter an area of higher CAPE where dry air became less of a problem and she was able to establish a strong core, a large eye was present for a while before later constricting and with its smaller size, came stronger winds. In the early morning hours of August 27th a surprise special advisory was given by the NHC which stated that Danielle had become the first major hurricane of the season, and only a couple of hours later she was upgraded further to Category 4. At time of writing this she is still currently a Category 4 hurricane and is forecast to pass safely east of Bermuda.
Eyes are also currently on Tropical Storm Earl which is nearing hurricane intensity and is forecast to also become a major hurricane, and pass north of the Caribbean Islands. But the path of Earl is not set in stone and those in the Caribbean should still be paying attention to Earl as he tracks WNW currently. It is expected that Earl will become a strong hurricane and manage to follow Danielle into a weakness in the ridge and become a fish storm, though as mentioned above there are still options for Earl regarding his paths.
Currently my eyes are also on the Invest 97L which is ANOTHER Cape Verdes system which is developing rapidly and could become a tropical depression by the end of the day. This system would be (possibly) too far East at the moment to catch the right timing to slip into the same weakness that Earl and Danielle and going through. Models are also showing strong ridging off the east coast in the 240 hour period, with the EURO currently forecasting an extremely strong major hurricane heading towards the east coast of the CONUS from the current Invest 97L. Now being 10 days out a lot can change and likely will, but should the upper air pattern than the EURO is depicting remain as forecast and should conditions remain so favourable for 97L, the East Coast could be looking at a serious hurricane thread come 2 weeks time.
So while the season started off appearing as though anything and everything would be killed off by unfavourable conditions which seemed to appear from nowhere, things have changed it would seem. The switch has been turned on and we are now into the real active period of the 2010 hurricane season.