Wow, that's a lot of damage.
Using the Advisories below it appears that St Lucia and some of the othe Islands were receiving 34 mph Tropical Storm force winds for over 24 hours. With winds possibly reaching over 90 mph.

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL212010
800 AM AST SAT OCT 30 2010

...TOMAS CAUSES DAMAGE ON BARBADOS...NOW HEADING TOWARD THE
NORTHERN WINDWARD ISLANDS AT NEAR-HURRICANE STRENGTH...

SUMMARY OF 800 AM AST...1200 UTC...INFORMATION
----------------------------------------------
LOCATION...13.1N 60.1W
ABOUT 70 MI...115 KM SE OF ST. LUCIA
ABOUT 70 MI...115 KM E OF ST. VINCENT
MAXIMUM SUSTAINED WINDS...70 MPH...110 KM/HR
PRESENT MOVEMENT...WNW OR 300 DEGREES AT 15 MPH...24 KM/HR
MINIMUM CENTRAL PRESSURE...993 MB...29.32 INCHES
TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 105 MILES...165 KM
FROM THE CENTER.

NWS TPC/NATIONAL HURRICANE CENTER MIAMI FL AL212010
800 PM AST SAT OCT 30 2010

...CORE OF TOMAS MOVING AWAY FROM ST. VINCENT AND ST. LUCIA...

SUMMARY OF 800 PM AST...0000 UTC...INFORMATION
----------------------------------------------
LOCATION...13.5N 61.7W
ABOUT 40 MI...70 KM NW OF ST. VINCENT
ABOUT 50 MI...85 KM WSW OF ST. LUCIA
MAXIMUM SUSTAINED WINDS...90 MPH...150 KM/HR
PRESENT MOVEMENT...WNW OR 285 DEGREES AT 9 MPH...15 KM/HR
MINIMUM CENTRAL PRESSURE...982 MB...29.00 INCHES

HURRICANE FORCE WINDS EXTEND OUTWARD UP TO 25 MILES...35 KM...FROM
THE CENTER...AND TROPICAL STORM FORCE WINDS EXTEND OUTWARD UP TO 175
MILES...280 KM.