TROPICAL DEPRESSION ONE DISCUSSION NUMBER 1
NWS NATIONAL HURRICANE CENTER MIAMI FL AL012014
1100 PM EDT MON JUN 30 2014
Convection associated with the area of low pressure off the east
coast of Florida has increased and become a little more organized
during the past few hours. Radar data shows that the convection has
developed into a band over the southeastern and southern portions of
the circulation. Based on these data, advisories are being
initiated on the first tropical depression of the 2014 Atlantic
hurricane season. The initial intensity is set to 30 kt, which is
in agreement with data from the earlier Air Force reserve
reconnaissance aircraft mission.
The south to southwest motion of the cyclone over the past couple of
days seems to have slowed this evening. The initial motion
estimate is 225/2 kt. The model guidance indicates that the
depression should begin to move slowly westward tonight and early
Tuesday. After that time, a building mid-level ridge over the
western Atlantic will begin to steer the cyclone northwestward
then northward. A large deep-layer trough that is forecast to
approach the eastern United States in a couple of days, should
cause the cyclone to turn northeast and accelerate. The model
guidance is in good agreement on this scenario, but there is
still significant uncertainty on how close the system will get to
the coast of the southeastern United States.
Low shear and warm sea surface temperatures along the forecast track are expected to allow gradual strengthening during the next few
days. The depression is forecast to become a tropical storm on
Tuesday and this is in line with all of the reliable intensity
guidance. The NHC intensity forecast is close to a blend of the
SHIPS/LGEM guidance. Late in the forecast period, the cyclone is
forecast to interact with the aforementioned trough and become
extratropical by day 5.
Due to the expected close approach of the system to the coast of
east-central Florida and likely strengthening during the next day or two, a tropical storm watch has been issued for portions of that area. Interests elsewhere along the coast of the southeastern United States should monitor the progress of this system.