Gordon hits the Azores; new Invest 96L; Helene heads out to sea

A strong tropical wave with plenty of heavy thunderstorm activity and some low-level spin has developed near 9N 29W, about 450 miles southwest of the Cape Verde Islands off the coast of Africa. This wave has been officially designated as "Invest 96L" by the Hurricane Center this morning. The storm is under about 10 knots of vertical wind shear and is over warm ocean waters of about 28C, so some slow development is possible over the next few days as it moves west-northwest over the open Atlantic. Most of the models predict slow development will occur, but none develop it into a hurricane. The long range GFS model predicts that this system will pass north of the Lesser Antilles Islands and possibly threaten Bermuda before recurving out to sea.


Figure 1. Preliminary model tracks for Invest 96L.

Hurricane Helene headed out to sea
Hurricane Helene has begun her expected turn towards the northwest, and is on track to recurve harmlessly out to sea. Helene has weakened some since yesterday--wind shear from the trough to her west has eroded the cloud pattern on that side, and the storm now has a distinctly lopsided appearance on satellite imagery. Helen is still over relatively warm water and under light wind shear, so may be able to reintensify into a Category 3 hurricane later today or tomorrow.


Figure 2. This morning's line-up of storms. Image credit: Naval Research Laboratory, Monterey.

Gordon pounds the Azores
Hurricane Gordon whipped through the Azores islands this morning as a Category 1 hurricane, but preliminary reports indicate no deaths or injuries occurred, and little damage was reported. Animations of satellite microwave imagery from CIMSS show that the center of Gordon passed over the southeastern-most island of Santa Maria, where power outages and fallen trees blocking roads created some minor problems. Winds on Santa Maria Island at 8am local time peaked at 56 mph, gusting to 82 mph. Gordon is rapidly weakening over cold waters, and is expected to become a powerful extratropical storm this afternoon. Gordon may cause trouble for golf's Ryder Cup in Ireland, due to begin Friday. Gordon is expected to move over or just offshore Ireland as a powerful extratropical storm on Friday and stall there, bringing high winds and intermittent heavy rain to Ireland for several days.

Hurricane history of the Azores
The Portuguese-owned Azores Islands, located about 1,500 km (930 miles) off the western coast of Europe, does not have a long and storied hurricane history. The ocean waters surrounding the islands are typically 22-23 C during hurricane season, which is 4-5 C below what is needed to sustain a hurricane. Occasionally, a fast-moving hurricane caught in the jet stream can make it all the way to the islands before decaying to a tropical storm; Gordon is the ninth hurricane since 1900 that managed to affect the Azores. All of these were Category 1 storms except for a Category 2 storm in 1926. I could find no mention anywhere of any deaths or damage having occurred as the result of these hurricanes.

The last time a hurricane hit the Azores was in 1998, when the not-so-terrible version of Hurricane Ivan passed through as a Category 1 storm. Ivan missed hitting any populated islands directly, and did little damage. Hurricane Emmy passed through the Azores in 1976 as a Category 1 storm. Emmy also did little damage, but tragically, a Venezuelan Air Force airplane carrying a school choir to Europe tried to land in the Azores at the height of the hurricane and crashed, killing all 68 people on board. The other major hurricane related tragedy to affect the islands occurred on On September 21, 1957, when the German sailing ship Pamir, with 86 crewmen aboard, was caught in Category 1 Hurricane Carrie. The ship sank, and only six survivors were found after a massive rescue effort. The shipwreck received enormous international media attention as a result and was perceived as a worldwide tragedy.

My next update will be Friday morning.
Jeff Masters