Wednesday, September 28, 2016

Hurricane Watch: "Tropical Storm Matthew Forms in the Lesser Antilles Islands"

First up, Wunderblog:

By: Jeff Masters , 3:23 PM GMT on September 28, 2016
Tropical Storm Warnings are flying in the Lesser Antilles Islands thanks to newly-formed Tropical Storm Matthew. An Air Force hurricane hunter aircraft found on Wednesday morning that Invest 97L had finally developed a closed circulation, and had surface winds near 60 mph in a powerful cluster of thunderstorms that was located about 50 miles east of Martinique at 9:22 am EDT. These strong winds will move over the islands of Martinique and Dominica early this afternoon, given Matthew’s westerly motion at 20 mph. At 11 am EDT, Dominica reported sustained winds of 33 mph, gusting to 53 mph, and Martinique reported sustained winds of 28 mph, gusting to 40 mph. Radar imagery out of Martinique and Barbados on Wednesday morning showed plenty of rotation to the storm’s echoes, and an increase in their intensity and areal coverage. Satellite loops showed that Matthew was developing a well-defined surface circulation, and had an increasing amount of heavy thunderstorm activity that was growing more organized. Aiding development was moderate wind shear of 10 - 20 knots and warm ocean waters of 29.5°C (85°F). The 8 am EDT Tuesday SHIPS model output analyzed 50 - 55% relative humidity at mid-levels of the atmosphere over Matthew, which is lower than optimal for tropical cyclone formation, and water vapor satellite loops showed Matthew was butting into a region of dry air that lay just west of the Lesser Antilles Islands. Lack of spin from being too close to the equator was less of a problem for Matthew than before, as the system had worked its way northwards to a latitude of 13°N. This is far enough from the equator for the storm to be able to leverage the Earth’s spin and acquire more spin of its own. ...MUCH MORE
Here's the Cone of Uncertainty:

Tropical Storm Matthew

And from the Washington Post's Capital Weather Gang:

Tropical Storm Matthew’s forecast is eerily similar to Hurricane Hazel in 1954
 Hurricane Hazel took this track in 1954. It made landfall in the Carolinas as a Category 4. (NOAA/Angela Fritz)
Tropical Storm Matthew formed just east of the Caribbean Sea on Wednesday morning, and the storm’s future track is concerning. After this weekend, forecast models are honing in on a path north and toward the U.S. coast. Amazingly — maybe foreboding-ly — it’s the same track that Hurricane Hazel took in 1954, which raked through the Mid-Atlantic and Northeast after making landfall as a Category 4. 
Hazel was just one of three major hurricanes that struck the coast that year, but that storm in particular prompted large and lasting efforts to improve hurricane observations, forecasts and warnings. 
Tropical Storm Matthew is expected to track west into the middle of the Caribbean through early next week. That is a high-confidence forecast. Beyond Monday, though, two of our most-trusted forecast models, the European and the GFS, are suggesting the storm will strengthen into a hurricane and take a dramatic turn to the north....MORE
Please note: These images are not actual official forecasts. They are possible scenarios....