Attachments
1 INTRODUCTION
This event briefing describes the impact of rainfall on Barbados, which was associated with a Covered Area Rainfall Event (CARE) on 3 July 2024. The Rainfall Index Loss (RIL) for the Covered Area Rainfall Event was below the attachment point of Barbados’ Excess Rainfall policy, and therefore no payout is due to the Government of Barbados.
2 EVENT DESCRIPTION
On 29 June at 0300UTC, the US National Hurricane Center (NHC) reported that a tropical storm formed in the central tropical Atlantic Ocean, and it was named Beryl. The system proceeded westward with estimated forward velocity of 18 mph (30 km/h), along the southern periphery of a strong subtropical ridge. In the next 30 hours, the tropical storm rapidly intensified due to the low wind shear, the high moisture content and the warm surface temperature over the tropical Atlantic. Thus, on 29 June at 2100UTC it became a hurricane and on 30 June at 1530UTC, it evolved into a Category 4 hurricane, as reported by NHC. At this time, the centre of Beryl was sited near latitude 10.8° North, longitude 54.9° West, about 350 mi (565 km) ESE of Barbados, and it proceeded towards the Windward Islands with almost unvaried forward velocity and direction. The maximum sustained winds were estimated at 130 mph (215 km/h) and the minimum central pressure at 962 mb.
During the final hours of 30 June and the first hours of 1 July, despite the environmental conditions that were still supportive for the intensification of the hurricane, an eyewall replacement cycle hindered the further strengthening of the system. Indeed, a new outer eye formed outside the small inner core, weakening the latter and gradually becoming dominant. For this reason, when Beryl started to affect the Windward Islands with tropical-storm conditions, during the first hours of 1 July, it had weakened to a Category 3 hurricane, with maximum sustained winds estimated at 120 mph (195 km/h)
Barbados was only partially affected by the heavy rainfall associated with Hurricane Beryl. Indeed, the radar maps showed that a first outer rainband passed rapidly over Barbados at around 0300UTC, bringing showers of moderate intensity over the country. Then, between 0600UTC and 1200UTC, Beryl passed over the waters between Barbados and Tobago (Figures 1a and 2a). At its closest distance, at 0900UTC, the centre of Beryl was sited at latitude 11.4° North, longitude 59.5° West, about 99 mi (160km) SSW of Bridgetown (Barbados), Figure 1a. The rainfall associated with the hurricane’s core brushed the southern coast of Barbados from 0600UTC until 1200UTC, as visible from the radar maps (Figures 3a, 3b and 3c).
At 1200UTC, Hurricane Beryl strengthened again, due to the completion of the eye replacement cycle and became a Category 4 hurricane again. It proceeded north-northwestward moving towards Grenada. At 1500UTC, while the eye was making landfall over Grenada, the northeastern outer rainband of the hurricane passed rapidly in the vicinity of Barbados, bringing again scattered moderate to isolated intense precipitation over the country (Figure 3d).
Hurricane Beryl then moved away from the southern Windward Islands, proceeding west- northwestwards at almost 20 mph (31km/h), towards the central Caribbean Sea.
Two days later, on 3 July, when Hurricane Beryl was in the vicinity of Jamaica, a powerful tropical wave crossed the Lesser Antilles. At 1200UTC, its axis was near longitude 61°West, and it was moving very rapidly westward at 29-35 mph (46 -55 km/h), as visible in Figure 1b. The satellite imagery showed that scattered moderate to isolated strong convection developed ahead and in the vicinity of the tropical wave, over an extended area from latitude 10°North to 16°North, between longitude 57°West and 65°West (Figure 2b). In particular, a thunderstorm affected Barbados with moderate to heavy rainfall from 1100UTC until 1400UTC, as shown by the radar maps (Figures 3e and 3f).