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1754

MONTHLY WEATHER REVIEW

VOLUME 133

Matamoros, Mexico, near Boca San Rafael. The hur- ricane weakened rapidly after landfall and dissipated on 17 August over the mountains of northeastern Mexico.

erative observing sites reported rainfall totals of less than 50 mm, although unofficial reports of up to 75 mm were also received from the Brownsville area. Doppler radar estimated isolated accumulations of 100150 mm

in Kenedy and Brooks counties.

2) METEOROLOGICAL STATISTICS

Despite an impressive and organized appearance on satellite imagery, the rapid westward motion of the pre- Erika disturbance hindered the development of a closed surface circulation. Data from reconnaissance aircraft, including dropsondes, were instrumental in de- termining when the disturbance became a tropical cy- clone. Around 0800 UTC 14 August, aircraft flight- level data at 850 mb indicated the presence of a closed circulation just east of Key Largo, Florida. However a dropsonde revealed that the west winds measured by the aircraft were not present below flight level and ad- visories were not initiated until later in the day, when a new low-level circulation formed within the system over the eastern Gulf of Mexico.

Erika was never operationally upgraded to a hurri- cane. The highest flight-level observations from recon- naissance aircraft were 67 and 66 kt at 0213 and 0820 UTC 16 August, respectively. These observations were made at 700 mb and correspond to a surface wind of about 60 kt (the operational landfall intensity). A post- storm review of the Doppler velocity data revealed winds in excess of 85 kt over an area several miles across, in the eastern and northeastern (over water) portion of the eyewall near the time of landfall, from around 10001200 UTC, at an elevation of about 762 m. Adjustment of these (85 kt) winds to the surface, using a mean eyewall wind profile based on dropwindsonde observations (Franklin et al. 2003a), gives a surface wind estimate of 65 kt. There were no aircraft recon- naissance observations in this part of the cyclone after 0820 UTC. On the basis of the radar observations, Erika was posthumously upgraded to a hurricane. A pressure fall of at least 5 mb after the time of the 67-kt flight-level wind also suggests that Erika reached hur- ricane intensity. The estimated minimum pressure (986 mb) at landfall was determined by extrapolation of the pre-landfall deepening rate.

Selected surface observations from land stations and data buoys are given in Table 4. The strongest sustained wind observed over land was 35 kt (10-min mean) at San Fernando, Mexico, with a gust to 55 kt. In south Texas, sustained tropical storm force winds were ob- served in Brownsville.

In Magueyes, Mexico, 170 mm of rain was recorded. A number of other sites reported storm-total rainfall of 75 mm or more. In southern Texas, official and coop-

3) CASUALTY AND DAMAGES

Two persons died in Montemorelos, Mexico, when they tried to cross a bridge that was partially under water and their truck was swept away by flood waters. Damage to roofs and cars was reported in Matamoros, and numerous highways in northeastern Mexico were blocked by mud slides.

Isolated minor damage was reported in south Texas from minor coastal flooding and beach erosion on South Padre Island. There were no injuries or fatalities reported in the United States.

4) WARNINGS

A hurricane watch was issued at 0300 UTC 15 Au- gust for the southern Texas coast and for the northern Mexican coast about 31 h prior to landfall. A hurricane warning was issued at 1500 UTC 15 August, or about 19 h prior to landfall. The center of Erika came ashore roughly in the center of the hurricane warning area.

f. Hurricane Fabian, 27 August8 September

Fabian was a long-lived and powerful Cape Verde hurricane that struck Bermuda with category-3 inten- sity. It caused extensive damage on that island, where it was reported to be the worst hurricane since 1926.

1) SYNOPTIC HISTORY

Fabian began as a vigorous tropical wave that emerged from western Africa on 25 August and moved westward through the Cape Verde Islands a day later. By 27 August, the deep convection associated with the system became more consolidated in a circular area, and it is estimated that a tropical depression formed at 1800 UTC, centered about 365 n mi west of the west- ernmost Cape Verde Islands. The depression became a tropical storm around 1200 UTC 28 August, and a hur- ricane by 0000 UTC 30 August over the east-central tropical Atlantic Ocean. Fabian reached its estimated peak intensity of 125 kt at 1800 UTC 1 September when it was centered about 265 n mi east-northeast of the northern Leeward Islands. The hurricane maintained category-3 or -4 intensity on the SaffirSimpson hurri- cane scale for almost a week.

Fabian was steered on a westward to west-northwest-

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