| hurricane | |
|---|---|
| Formed | September 25, 2003 |
| Dissipated | October 7, 2003 |
Hurricane Kate had a long, rather unusual track over the east-central Atlantic. It became a powerful hurricane at subtropical latitudes.
Storm history
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Tropical storm (39–73 mph, 63–118 km/h)
Category 1 (74–95 mph, 119–153 km/h)
Category 2 (96–110 mph, 154–177 km/h)
Category 3 (111–129 mph, 178–208 km/h)
Category 4 (130–156 mph, 209–251 km/h)
Category 5 (≥157 mph, ≥252 km/h)
Unknown
Extratropical cyclone, remnant low, tropical disturbance, or monsoon depressionA tropical wave crossed the coast of western Africa on 21 September and moved slowly westward, passing near the Cape Verde Islands on 23 September. Although the system was not well organized, meteorologists identified a low-level circulation center several hundred miles west-southwest of the Cape Verde Islands on 24 September. Cloudiness and deep convection gradually became better organized into curved bands, and initial Dvorak T-numbers were assigned around 1200 UTC 25 September. It is estimated that a tropical depression formed, roughly 800 nm west-southwest of the Cape Verde Islands, at 1800 UTC 25 September.
The tropical dperession moved generally northwestward for a couple of days toward a weakness in the subtropical ridge over the central Atlantic. Meanwhile, south-southwesterly upper-level flow caused strong vertical shear over the depression, and the low-cloud center was intermittently exposed to the southwest of the main area of deep convection. Around 1800 UTC 27 September, deep convection increased near the center, and satellite-based estimates indicate that the cyclone became Tropical Storm Kate. Even though the system continued to experience moderate southwesterly shearing, it strengthened further over the next two days while turning northward and northeastward. Kate briefly became a hurricane, from about 1800 UTC 29 September to 0000 UTC 30 September. Then, while weakening, the cyclone took a hairpin turn around the eastern side of a mid-tropospheric cyclonic circulation. By 1 October, Kate was moving west-southwestward on the northern side of the cyclonic circulation. It also regained hurricane strength that day. Kate continued west-southwestward for the next couple of days, guided by the steering flow between an anticyclone to its north and the cyclonic circulation centered to its south. There was an area of weak vertical shear over the area, and as Kate moved over warmer waters, it strengthened rapidly. By 2 October, a well-defined eye was apparent on satellite images. The hurricane moved westward to west-northwestward over the next couple of days while strengthening to its peak wind intensity of 125 mph (205 km/h) at 1800 UTC 4 October. Kate was located about 565 nm east-southeast of Bermuda at that time.
Shortly after reaching maximum intensity, the western portion of the hurricane's eye became partially disspeard, which shows the beginning of a weakening phase. Also, the forward speed slowed from 10-11 knots to 6-7 knots as Kate neared the western periphery of the deep-layer anticyclone that had been anchored over the north Atlantic for several days. On 5–6 October, the cyclone turned northward, then accelerated north-northeastward ahead of a deep-layer trough. Kate was slow to weaken as an eye was occasionally visible on satellite imagery. It entred CHC's area of responsibility as a weak Category 1 hurricane early on 7 October. However, Kate finally weakened below hurricane strength on the same day while it continued to accelerate north-northeastward over cooler waters. Kate also began losing tropical characteristics as cold air clouds wrapped around the center over the southern portion of the circulation, and the remaining central convection weakened and became disorganized. The system completed its extratropical transition by 0000 UTC 8 October, but remained a formidable extratropical storm for a couple more days while moving northeastward to eastward across the northern Atlantic. It merged with another extratropical low near Scandinavia on 10 October.
Impact
editNo significant damage or fatalities were reported in relation to Kate, although heavy rain was reported in coastal areas of southeastern Newfoundland. Hurricane Kate was most remembered for the fear it brought to the Canadian Hurricane Centre as it neared Canada, especially being less than a week after Hurricane Juan. Rainfall from Kate was difficult to determine because tropical cyclone moisture was feeding into a stalled frontal system over the province of Newfoundland. The 24-hour radar derived storm total rainfalls calibrated against surface reports suggest upwards of 100 mm in some regions of southeastern Newfoundland from the combined effects of these two features. The CHC issued 22 bulletins.
