USAirways has a Travel Advisory up for SXM and SJU, as well as for some other Caribbean destinations.
http://www.usairways.com/TravelCenter/Advisories.aspx#236
Travel advisory
Tropical Storm Gonzalo
10/12/2014 4:42 PM ET
Cities Affected
Antigua, Antigua and Barbuda ; Pointe A Pitre, Guadeloupe ; Fort De France, Martinique ; San Juan, PR ; St. Kitts, Saint Kitts and Nevis ; St. Maarten, St Maarten ; St. Croix, VI ; St. Thomas, VI
Date Range
10/13/2014 1:00 AM ET through 10/14/2014 11:59 PM ET
Revised Ticket Policy
Due to the weather situation in the Caribbean, US Airways offers the following flexibility options to our ticketed customers whose travel may be impacted by this event. Customers ticketed to travel on US*/AA flights to/from/through the airports listed below may change flights as shown below.
If you are traveling to, through or from:
St. Johns, Antigua (ANU)
Fort de France, Martinique
Pointe a Pitre, Guadeloupe (FDF)
San Juan, PR (PTP)
St. Kitts, Nevis (SJU)
St. Thomas, USVI (SKB)
St. Croix, USVI (STT)
St Maarten, Netherlands Antilles (SXM)
On the following dates:
October 13 - 14, 2014
And your ticket was issued no later than:
October 13, 2014
You may travel:
October 13 - 17, 2014
Original inventory required?
No
Origin/Destination/Stopover Changes allowed?
No
The ticket reissue charge will be waived for one ticket change
Change your trip online at usairways.com/manageyourtrip
If you need help, please call 800-428-4322.
American Airlines has a similar advisory posted.
http://www.aa.com/i18n/travelInformation/travelAlerts.jsp