Bertha (2014)

A tropical wave moving off West Africa late on July 24 developed into a low pressure area at the end of July and became Tropical Storm Bertha at 0000 UTC 1 August 2014 about 300 nautical miles east-southeast of Barbados. The storm moved quickly west to west-northwest across the northeastern Caribbean, weakened briefly near Puerto Rico, then reorganized and rapidly intensified to hurricane strength early on 4 August about 170 nmi north-northeast of San Salvador in the central Bahamas. Bertha weakened thereafter, turned north and then northeast, became extratropical by 1800 UTC 6 August about 250 nmi south-southeast of Halifax, Nova Scotia, and dissipated several days later well east of Newfoundland.

Bertha did not make a U.S. mainland landfall. It passed near and over several Caribbean islands as a tropical storm: it passed just north of Martinique late on 1 August and moved close to the northeast coast of the Dominican Republic on 3 August. The best-track record also shows a landfall on Middle Caicos Island (Turks and Caicos) around 1400 UTC 3 August as a 40‑kt tropical storm. No other formal tropical‑cyclone-intensity landfalls on major islands are listed beyond those close passages.

The storm’s peak intensity was estimated at 70 knots (80 mph) with a minimum central pressure of 998 millibars, making Bertha a Category 1 hurricane at its strongest (early 4 August). Peak winds were supported by aircraft flight-level winds of 86 kt and surface estimates from the SFMR instrument near 72 kt; satellite estimates had been lower.

Storm surge and rainfall impacts were mainly in the Caribbean. The report noted no large surge damages but provided specific rainfall totals: Puerto Rico’s mountainous central region received the most, with a maximum of 11.11 inches (Adjuntas). Bayaguana in the Dominican Republic reported 4.7 inches (119.5 mm). Numerous islands reported tropical-storm-force gusts (for example, sustained/gusts near 34–40 kt reported at points in Martinique, Guadeloupe, St. Thomas, St. Croix, and several buoys).

There were two direct deaths in the United States from rip currents produced by Bertha: one person near Frisco, North Carolina, and one near Atlantic City, New Jersey. No significant structural damage estimates were reported. The largest reported disruption was on Martinique, where power outages affected about 150,000 buildings; flooding, mudslides, and some road collapses were reported in Puerto Rico and the Dominican Republic but overall damage was considered relatively minor.

Noteworthy items: Bertha exhibited an erratic early life with periods of weakening and possible brief loss of a closed circulation before rapidly intensifying over warm waters on 4 August. NHC track forecasts for Bertha performed better than recent averages and most models, while intensity forecasts had mixed performance—official forecasts anticipated eventual hurricane development but the storm intensified sooner than expected and then weakened faster than forecast.