Irma expected to be hurricane by weeks end

[jpak]

Source: Miami Herald

Tropical Storm Irma picked up strength Wednesday and is expected to become a hurricane by Thursday or Friday, making it the fourth hurricane of an increasingly busy season.

In their latest advisory, National Hurricane Center forecasters said sustained winds had reached 60 mph as the storm rolls west at 15 mph. While it’s too early to tell what threat Irma may pose to Florida or the U.S. Coast, it has the potential to gain significant strength as it crosses warm tropical Atlantic waters — sea surface temperatures are more than 2°F above normal — and encounters weak wind shear.

Irma is moving along the southern edge of a high pressure system that’s helping steering it, forecasters said. During the next three days, it’s expected to slow and begin turning toward the southwest. However, after that, the models diverge on which path the storm will take.

What worries meteorologists is that the storm will track very close to a latitude and longitude in the tropical Atlantic that historically proved a turning point for threats to the islands and the U.S. coast. It’s also not yet clear whether the high pressure system, or a low pressure trough, will win out in a tug of war over which direction it takes.

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Read more: http://www.miamiherald.com/news/weather/hurricane/article170153002.html

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[catbyte]

1. Oh, great. Another Cape Verde Hurricane of August/early September.

Some of the worst storms in history have originated there. If it gets close to the US, I shudder to think what could happen.

Cape Verde Hurricanes

A Cape Verde hurricane is an Atlantic hurricane that originates at low-latitude in the deep tropics, titularly from a tropical wave that has passed over or near the Cape Verde islands after exiting the coast of West Africa. The average hurricane season has about two Cape Verde hurricanes, which are often the largest and most intense storms of the season due to having plenty of warm open ocean over which to develop before encountering land or other factors prompting weakening. A good portion of Cape Verde storms are large, some setting records. Most of the longest-lived tropical cyclones in the Atlantic basin are Cape Verde hurricanes. While many move harmlessly out to sea, some move across the Caribbean sea and into the Gulf of Mexico, becoming damaging storms for Caribbean nations, Central America, Mexico, Bermuda, the United States, and occasionally even Canada. Research projects since the 1970s have been launched to understand the formation of these storms.

Origin

Prior to the early 1940s, the term Cape Verde hurricane referred to August and early September storms that formed to the east of the surface plotting charts in use at the time.[1] Cape Verde hurricanes typically develop from tropical waves which form in the African savanna during the wet season, then move into the African steppes. The disturbances move off the western coast of Africa and become tropical storms or tropical cyclones soon after moving off the coast,[2] within 10 to 15 degrees longitude, or 10,760 kilometres (6,690 mi) to 16,140 kilometres (10,030 mi), of the Cape Verde Islands;[1] this comprises the tropical latitudes east of the 40th meridian west. In the years since the phrase's coining, increasing detection has allowed meteorologists to determine that Cape Verde hurricanes have formed as early as 0600 UTC on July 3 (Hurricane Bertha of 2008) or as late as 1800 UTC on September 26 (Hurricane Noel of 1995).

...snip

https://www.revolvy.com/main/index.php?s=Cape%20Verde%20hurricane

[Dustlawyer]

2. Crap! it is someone else's turn!

[Best_man23]

3. Crap

Where's some good Saharan dust when you need it.

Saharan dust and the Saharan Air Layer combine to inhibit hurricane formation and strength.

[SunSeeker]

4. I've got a bad feeling about this one...

[nitpicker]

5. Let's hope it's not another I storm like

Isabel
Ivan
Ike

[jpak]

6. Irma reaches *major hurricane* status

http://www.nhc.noaa.gov/storm_graphics/AT11/refresh/AL112017_5day_cone_no_line_and_wind+png/145426_5day_cone_no_line_and_wind.png