[ HOME ]
Western Samoa's climate is tropical. Although it is in the southern hemisphere, because of it's proximity to the equator there is no major seasonal difference such as the summer and winter that occurs in more temperate regions. There is however a rainy and a dry season and a slight difference in temperature associated with these. Another effect of being in the tropics is that the days and nights are of almost equal length, so if you want to get the most out the day you should really be an early riser.
Occaisonally Samoa is affected by a cyclone, most recently in 1993 the damage from that cyclone still being visible in some of the more remote areas such as Falealupo on Savai'i.
The islands are volcanic and there is an active volcano on Savai'i. The region does have occasional small tremors.
The rainy season in Samoa is centered around January and the dry season around July and August. Because the interior of the island is mountainous there is also a considerable difference between the rainfall on the coast and that in the jungle further inland. Northern and western shores receive about 100 inches (2.5 meters) and inland areas about 300 inches (7.5 meters) a year. If you are in Samoa during the rainy season you can expect to get wet on two out of three days.
Modified: 23rd November 1997
There is very little seasonal difference in the temperature as, some shown by the graph
below. During the period May - November the weather is slightly cooler because of the
presence of the South East Trade Winds.
Modified: 23rd November 1997
I have been unable to locate a series of humidity data, but needless to say it is generally humid in Samoa with the humidity being at it's greatest in the rainy season, about 79%, and at about 73% in the dry season. It is not uncommon to change your clothes several times a day.
Each year from 1989 to 1993 Samoa was hit by severe cyclones. The worst being Cyclone Val in 1992 which defoliated 90% of the island and destroyed about half of the islands coconut rees, which ultimately had a detrimental effect on the country's economy. Cyclones of this severity are, fortunately, unusual. The cyclone season is usually between January and March. There is currently some debate about whether this is likely to change because of a perceived permanency to the Southern Oscilation of the El Nino effect.
Modified: 23rd November 1997
Current Tropical Storm Tracks
CURRENTLY NOT AVAILABLE
Visible Spectrum (4 minutes download - loaded into new browser window)
False colour satellite images of Samoa
The Pacific is one of the most tectonically active areas of the world, being surrounded by the Ring of Fire and having numerous volcanic islands scattered across it. Compared to most areas in the Pacific, Samoa is relatively quiet. Below is a table of earthquakes from 1990 and a map showing their distribution relative to Samoa.
Date Time Lat Lon Depth Mag Location 1990/01/10 07:41:08.1 13.139S 172.612W 33.0 4.8Mb MHDF SAMOA ISLANDS 1990/08/03 08:36:30.5 14.671S 173.388W 37.0 5.1Mb MHDF SAMOA ISLANDS REGION 1990/09/26 20:10:41.9 14.736S 173.372W 33.0 5.0Mb MHDF SAMOA ISLANDS REGION 1990/11/04 06:55:59.8 13.117S 173.466W 33.0 4.7Mb MHDF SAMOA ISLANDS REGION 1990/12/11 18:55:35.4 14.885S 172.802W 33.0 4.6Mb MHDF SAMOA ISLANDS 1991/02/22 20:14:28.3 14.750S 173.044W 33.0 4.1Mb MHDF SAMOA ISLANDS REGION 1992/01/31 04:02:00.2 14.988S 173.048W 33.0 4.2Mb MHDF SAMOA ISLANDS REGION 1993/05/03 23:15:06.6 14.404S 173.021W 23.0 5.1Mb MHDF SAMOA ISLANDS REGION 1994/09/02 11:59:41.7 14.909S 172.122W 35.0 4.2Mb MHDF SAMOA ISLANDS 1995/10/03 01:00:20.7 13.865S 171.299W 38.0 4.9Mb MHDF SAMOA ISLANDS 1995/10/06 22:35:05.0 14.917S 173.472W 33.0 4.5Mb MHDF SAMOA ISLANDS REGION 1996/05/10 22:05:57.7 14.871S 173.420W 33.0 4.2Mb WHDF SAMOA ISLANDS REGION 1996/05/26 03:17:02.2 14.973S 173.314W 33.0 3.9Mb WHDF SAMOA ISLANDS REGION 1996/06/15 02:43:25.6 14.941S 173.145W 33.0 4.6Mb WHDF SAMOA ISLANDS REGION 1996/06/30 22:04:49.5 14.968S 172.756W 33.0 4.8Mb WHDF SAMOA ISLANDS 1996/07/24 11:34:18.3 14.658S 172.950W 33.0 4.7Mb WHDF SAMOA ISLANDS 1996/09/24 23:19:05.1 14.999S 173.041W 33.0 0.0 WHDF SAMOA ISLANDS REGION
Modified: July 23rd 1998
Fortunately these are rather rare and Samoa is part of a Pacific wide monitoring and alert system, so any events that are likely to lead to a tsunami are quickly relayed to the radio and television stations.
- In the event of a confirmed tsunami you should head for high ground or get as far away from the coast as you can. This is not difficult to do in Samoa since there is only a narrow coastal strip around most of the islands and then it rises to inland mountains.
- Sometimes a tsunami is preceeded by an emptying of the lagoon as the water rushes out. DO NOT STOP TO WATCH OR EXPLORE THE LAGOON. Tsunami travel at several hundred miles an hour and before you know it you could be caught by the wave.
- Once the wave has struck, do not assume that you can go back to the shore. Quite often there can be a series of waves seperated by 20 minutes to half an hour. Only go back when the emergency services say it is safe.
The have been three volcanic eruptions on Savai'i in recent times. Mount Matavanu was last active between 1905 and 1910. Mount Mu erupted in 1902. Mount Afi erupted last some time around 1690.
Added: 24th November 1997
1 Source: The Global Historical Climatology Network
-GHCN version 1
2 Source: Pacific Daily Rainfall Data
3 Source: The IRIS Earthquake Database Search Engine
There is an observatory on the outskirts of Apia gathering seismic, oceanographic, meteorological and hydrographic data. If anyone knows if this data is available on the internet could you please let me know.