August 31 - September 1, 2003
Impacts in Hawaii
Andy Nash (email@example.com)
Jimena developed on August 28 about 1700 miles east-southeast of Hawaii and developed quickly. On August 30, it reached it's peak strength as a hurricane with sustained winds slightly over 100 mph. Jimena moved steadily westward around 17 mph on a course that would take the center about 50 miles south of the Big Island. On August 31, with Jimena about 300 miles east-southeast of the Big Island, the storm began to encounter stronger winds in the upper atmosphere that began to weaken and shear it apart. During the early morning hours of September 1, a rapidly weakening Jimena started moving in a southwest direction as it was now being pushed along by the low level tradewind flow from the northeast. Air Force Reserve aircraft reconnaissance could not find any winds above hurricane strength, and so Jimena was downgraded to a Tropical Storm. Jimena made it's closest approach to the Big Island around sunrise, with it located about 110 miles south of South Point. By that afternoon, much of the convection was gone and Jimena was now just a tropical depression as it continued to move southwest and away from the islands.
6 to 12 foot surf was reported along the coast of the Kau (southeast) district of the Big Island. 11 foot waves were also reported along the coast just north of Hilo.
Rainfall amounts of 6 to 10 inches, with higher isolated amounts, occurred across the windward sections of the Big Island. Very little rainfall fell across the remainder of the state. No significant flooding problems occurred, although the Wailuku River had significant rises but remained within it's banks.
Aircraft reconnaissance showed that the strongest winds (over 50 mph) remained within 50 miles of the center of Jimena, with Tropical Storm force (over 35 mph) winds extending only about 100 miles from the center. However, the increased pressure gradient between Jimena and the subtropical high pressure well north of the islands did act to increase the winds across the state. The complex topography of the islands also led to many areas seeing strong wind gusts as the accelerated trade winds flowed around and over the islands. The highest wind gust measured in the state was actually from the small island of Kahoolawe with an automated weather sensor reporting a gust to 58 mph. This is a normally windy spot, as it is affected by strong winds being funneled around Mount Haleakala on Maui. Highest wind gusts on the Big Island were 53 mph at South Point and at an automated weather station in the saddle between Mauna Loa and Mauna Kea.
|Honolulu, Oahu||36 mph|
|Lihue, Kauai||22 mph|
|Buoy 4 (SW of the Big Island)||31 mph|
|Buoy 2 (SE of the Big Island)||45 mph|
This was only the second time that the center of a tropical storm or hurricane has been close enough to be detected by radar since the 4 doppler radars were installed across the state in the early to mid 90s. The first time was in 1999 with Hurricane Dora (radar, report), however Jimena came much closer so that even wind velocity information could be detected by the radar. At the time Jimena was closest to the range of the 88D doppler radar in South Hawaii, it was beginning to rapidly deteroriate from a hurricane to tropical storm. Radar imagery confirmed the ragged structure of Jimena's center and associated rainbands, and lack of intense convection completely encircling the center. All are signs of a weakening system.
Note: in the following images, the circle around the island represents the 120 mile range mark from the radar site. For the reflectivity, the greens are generally light rain, yellows are moderate rain and the oranges and reds represent the heavy rainfall. For the velocity, the green and blue colors represent winds moving toward the radar, with blue representing the highest speeds of 40+ mph. The oranges and reds represent winds moving away from the radar, with dark red representing the highest speeds of 40+ mph.
Below are a series of satellite images showing the progression of Jimena as it approaches and moves south of the islands. The rapid deterioration of Jimena is obvious.
Bonus behind the scenes:
During significant weather situations, such as that presented by Jimena, many other things happen at the Honolulu Forecast Office/Central Pacific Hurricane Center that might not be so apparent to the general public.