Tropical Depression Four was a very small tropical cyclone with limited convection that approached the east coast of Florida. The precursor disturbance was a low that disengaged from a frontal zone in the central subtropical Atlantic on 4 August, and then moved southwestward over the next few days. An Air Force Reserve Command reconnaissance aircraft found a well-defined low level circulation with minimal convection on 8 August. The system then moved westward with no increase in strength for two days. On the 10th, the depression was about 70 nautical miles east of Cape Canaveral when it abruptly turned northeastward in advance of a deep-layer trough over the eastern United States. The depression dissipated the following day. The best track chart of the depression's path is given in Figure 1, and the complete best track is given in Table 1.
A reconnaissance wind report at 1500 ft of 47 kt could be used to argue that the depression attained tropical storm status. However, the (surface-adjusted) tropical storm force winds were reported during only one pass through the system and covered an area less than 10 nautical miles across. These winds are judged to have been unrepresentative of the system's maximum sustained wind and so the cyclone has not been designated as a tropical storm.
Table 1. Preliminary Best Track - Tropical Depression Four, 8-11 August 2000. Date/Time
(UTC)Position Pressure
(mb)Wind Speed
(kt)Stage Lat. (°N) Lon. (°W) 08 / 1200 28.2 74.2 1011 30 tropical depression 08 / 1800 28.1 75.1 1010 30 " 09 / 0000 28.0 76.0 1010 30 " 09 / 0600 27.9 76.8 1010 30 " 09 / 1200 27.9 77.4 1010 30 " 09 / 1800 27.9 77.9 1010 30 " 10 / 0000 28.0 78.6 1009 30 " 10 / 0600 28.3 79.3 1010 30 " 10 / 1200 28.7 78.9 1010 30 " 10 / 1800 28.9 78.3 1011 25 " 11 / 0000 29.2 77.8 1011 25 " 11 / 0600 29.4 77.2 1012 25 " 11 / 1200 29.6 76.5 1013 25 " 10 / 0000 28.0 78.6 1009 30 minimum pressure
Figure 1. Best track positions for Tropical Depression Four, 8-11 August 2000.
