Published: April 22,2016
Rapidly intensifying Tropical Cyclone Amos will make a close pass to Samoa and American Samoa this weekend as the strongest tropical cyclone to brush the islands in over three years.
A tropical cyclone warning has been issued for the Independent state of Samoa, and a tropical storm watch is in effect for American Samoa, including Pago Pago.
Tropical Cyclone Amos rapidly intensified to the equivalent of a Category 1 hurricane, and is now beginning to exhibit a more distinct eye in infrared satellite imagery, previously only discernible in microwave imagery.
Current Satellite
The center of Amos is expected to make its closest approach to the largest Samoan islands of Savai'i and Upolu Sunday, local time. While the eye is most likely to pass south of the islands, it may track close enough to bring some of the eyewall ashore in those islands.
Further strengthening is expected until that time, and Amos may be as strong as a Category 3 hurricane at its closest Samoan approach.
Amos is then expected to bend southeastward, which may keep the strongest winds south of American Samoa, including Pago Pago. A sharper, sooner southeast turn would lessen impacts in American Samoa.
Projected Path and Intensity
Potential Impacts
On its forecast track, the strongest winds are expected to affect Samoa, particularly the island of Savai'i and its higher terrain. Gusts over hurricane force is likely to down trees, trigger power outages, and lead to at least some structural damage to buildings.Storm surge flooding is likely particularly along the north-facing coasts of both Savai'i and Upolu, compounded by battering waves riding atop the surge.
According to the National Weather Service (NWS), tropical storm-force winds are possible in American Samoa by late Saturday, local time (7 hours behind U.S. Eastern time). Gusts to 50 mph may lead to some sporadic power outages and downed tree limbs. Somewhat higher gusts are possible over the islands' mountains. Keep in mind that any change in track and intensity of this storm could result in much greater or lesser impacts.
(MORE: Pago Pago Forecast)
Some storm surge flooding, to a lesser degree than in Independent Samoa, is also expected, particularly along north-facing coasts, particularly during high tide.
A high surf warning has been issued for all islands of American Samoa. Surf heights are expected to build to 26 feet Saturday and Sunday off the offshore reefs. Other impacts will include coastal erosion and strong rip currents.
Rainbands from Amos will increase in intensity by Friday night. As a result, NWS has issued a flash flood watch for all islands of American Samoa through Sunday.
Amos has the potential to dump anywhere from 5 to 20 inches of rain across Samoa and American Samoa, leading to dangerous, life-threatening flash flooding and mudslides through Sunday.
Residents should monitor the latest forecasts and prepare to take action if flash flood warnings are issued.
Pago Pago, American Samoa, has already picked up almost 19 inches of rain through the first three weeks of April, which is almost 8 inches above average for the entire month.
Amos is likely to be the strongest tropical cyclone to affect Samoa and American Samoa since Cyclone Evan in mid-December 2012. According to a 1990 technical report, a damaging tropical cyclone occurs on average every 8 years in Samoa.
No comments:
Post a Comment