Tuesday, September 21, 2010

Hurricane Lisa (2010)

Storm Active: September 20-26
The tropical wave that became Lisa emerged off of Africa on September 16. The cloud cover associated with the wave remained disorganized for a day, but a broad low pressure center formed on September 17. The low took a turn northwest before slowing its motion and drifting to the north over the next few days. This uncertain motion was caused by a weakness in the usual Azores high that pushes cyclones to the west, a weakness that was enlarged by Hurricane Julia a few days earlier. Meanwhile, the system became more organized, and was declared a tropical depression late on September 20. The depression soon strengthened into Tropical Storm Lisa.

The cyclone meandered northeast, then east, then south, and then east again through the next day, with no change in intensity. Some convection was lost during the day of September 21, and the system weakened to a tropical depression, still maintaining a slow east motion. By September 23, convection had organized enough for Lisa to become a tropical storm again, and the system was nearly stationary during that day. However, Lisa adopted a northward motion during the day of September 24, and continued strengthening.

By late on September 24, Lisa had quickly intensified to a hurricane, reaching its peak intensity of 80 mph winds and a pressure of 987 mb just before midnight. An eye feature even made a brief appearance. However, Lisa began quickly weakening the next day, as it moved into cooler waters. The system was a remnant low by the afternoon of September 26. Lisa moved north and quickly dissipated. The cyclone affected no land masses.

Lisa as a hurricane. It is obviously a very small storm.

Track of Lisa.