Wednesday, January 13, 2016

Wow! Extremely Rare January Hurricane Alex in Atlantic, Equally Rare Hurricane In The Pacific

Hurricane Alex in the eastern
Atlantic Ocean Thursday morning.
A hurricane in the Atlantic Ocean in
January is almost unheard of.
UPDATE:

Incredibly, Subtropical Storm Alex, already an extreme Atlantic Ocean rarity for January, stremgthened overnight into a full fledged hurricane.

Maximum sustained winds were 85 mph.

Hurricane warnings are up for many islands in the Azores.

On satellite images, Alex has really taken on the look of a full-fledged hurricane, with a well-defined eye and a thick towering eyewall of intense thunderstorms surrounding it.

Alex is the first hurricane to form in the Atlantic Ocean since 1938 and the first hurricane to be in the Atlantic since Alice in 1955

(Alice formed in December, 1954 and survived into the first few days of 1955.)

I'm also not aware of a hurricane coming onshore, or at least causing hurricane force winds, as it might in the Azores.

Now, this January, we had, as far as anybody can tell, the completely unprecedented situation of a hurricane in both the Atlantic and central Pacific during the month of January - and during the same week as well!

Alex is over water that is slightly cooler than what a hurricane can normally sustain, but it's winter, not summer, so the upper atmosphere is much colder than it would be during the traditional hurricane season. This increased contrast might have allowed the storm to form into a hurricane.

After Alex gets done with the Azores, it will convert back into a more "normal" non tropical storm, and be powerful as it makes a beeline toward the southern tip of Greenland.

PREVIOUS DISCUSSION:

Talk about getting the Atlantic hurricane season off to an early start!

Today, Subtropical Storm Alex formed in the eastern Atlantic Ocean. A subtropical storm is basically a tropical storm, but still has a few characteristics of a regular old storm.

But still,  any kind of tropical storm forming in the Atlantic Ocean in January is incredibly rare. Hurricane season starts June 1, and it's very, very, VERY odd for a tropical or subtropical storm to form before May, let alone in January.

In fact, this is the first January subtropical or tropical storm to form in the Atlantic since 1978.

Subtropical Storm Alex in the eastern Atlantic
Ocean Wednesday. It later strengthened, incredibly
into a hurricane, an extreme rarity in January 
Only four have been known to have formed in January since 1851, but there might have been others that were missed in the pre-satellite era.

The average date for the first tropical system of the season in the Atlantic Ocean is July 9, certainly not January 13.

As I noted a few days ago, forecasters have been watching this thing, which started out as a plain old wintertime storm near Bermuda, then drifted over warmer central and eastern Atlantic waters, where Alex took on tropical characteristics.

What helped was the water out there is even warmer than it normally is this time of year.

Alex is expected to move toward the Azores, and also move over colder waters. That will make it turn back into a regular old winter storm that could lash those islands with gusts to gale force around Friday or so.

It will then race off toward Greenland, or east of Greenland, as that aformentioned winter storm.

I don't think Alex has any bearing on how the "real" Atlantic hurricane season will turn out. I don't know if it will be a rough one or not. But if Atlantic waters remain warmer than normal through next fall, and El Nino fades by summer, it could be a busy season.

We'll have to wait and see.

Meanwhile, also as noted the other day, there's a hurricane in the central Pacific Ocean, again very much a rarity in January.

Hurricane Pali reached Category 2 status Tuesday with highest sustained winds of 100 mph.  It has set records for the earliest tropical system and hurricane to form in the central Pacific on record, notes the Honolulu Star-Advertiser.

As in the Atlantic, hurricanes don't normally form in the central Pacific until summer.

Pali is also setting records for being so close to the equator. Hurricanes, or any kind of storm for that matter, usually form pretty far north of the equator.

The earth spins faster at the equator than it does the more you go toward the North or South poles, because the Earth is widest at the equator.  This is called the Coriolis Effect and helps give storms the spin they need to maintain themselves.

The closer you are to the equator, the less spin a storm can stir up, so any kind of storm system is rare there.

It's actually possible that Pali might cross the equator, because its winds still have enough momentum now to get past the equator. If it does get into the Southern Hemisphere, it will quickly die out, because storms rotate in the opposite direction in the Southern Hemisphere than in the Northern Hemisphere.

So, the Southern Hemisphere flow would work in opposition to Pali's winds, and would quickly fall apart.

In any event, that tropical systems would develop during January in both the Pacific and Atlantic is something pretty much unheard of. Dr. Jeff Masters in his blog said this might not have been possible 30 years ago, when oceans were a bit cooler. Global warming has heated the waters up some.

Although we can't prove global warming created these two hurricanes, it's plausible that they were encouraged by climate change.

It probably didn't hurt that El Nino, Made Pali in particularly able to form in the Pacific Ocean

Still, all these tropical systems in January are very, very weird indeed.

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