Pacific ENSO Update

1st Quarter, 2008 Vol. 14 No. 1

Palau Flag Republic of the Marshall Islands: The 2007 annual rainfall totals at some of the atolls in the northern RMI were among the lowest values at any of the USAPI. While most atolls of the RMI were below normal for the year, the less than 50 inches of annual rainfall at Utirik and at Wotje represented only a little over half of the normal annual rainfall expected at those locations. The 118.66 inches at the WSO, Majuro, was 90% of normal. A strong 4th Quarter helped to boost the annual totals at Majuro, Arno and at Mili. Only at Mili with its 143.51 inches was the 2007 annual total above normal (109%).

Early in 2007, dry conditions prevailed in the northern RMI. Emergency measures had to be taken in order to insure adequate drinking water for some islands. Rainfall in the northern RMI will once again have to be monitored, as 2 or 3 months of rainfall below 5 inches per month could once again impact the supplies of potable water.

Republic of the Marshall Islands Rainfall Summary 4th Quarter 2007

Station   Oct. Nov. Dec. 4th Qtr
Annual
Majuro WSO Rainfall (inches)
20.74
20.31
10.89
51.94
118.66
% of Normal
150%
159%
92%
135%
90%
Laura* Rainfall (inches)
17.42
N/A
N/A
N/A
N/A
Arno* Rainfall (inches)
15.00
20.10
10.89
45.99
115.44
Alinglaplap* Rainfall (inches)
7.57
3.77
3.64
40.91
143.51
Mili* Rainfall (inches)
14.32
22.95
3.64
40.91
143.51
Kwajalein Rainfall (inches)
11.59
12.43
5.76
29.78
89.32
% of Normal
97%
117%
71%
97%
87%

Utirik*

Rainfall (inches)
10.16
3.96
1.33
15.45
47.71

Wotje*

Rainfall (inches)
12.85
4.06
2.25
19.16
49.95
* Long term normal is not established for these sites
** Estimated

Climate Outlook: Although near normal rainfall is anticipated for most of the atolls of the RMI for the next several months, it is now the dry season there, and even normal rainfall is less than 5 inches per month at Utirik and Wotje through March. Because of dry conditions during 2007, low rainfall in the next two or three months might impact potable water supplies on some atolls in the northern RMI. Residents of the northern RMI are thus urged to participate in voluntary water conservation measures. Normal summer rains should be experienced on all islands.

Forecast rainfall for the RMI from February 2008 through January 2009 is as follows:

Inclusive Period
% of Long-Term Average Rainfall /
Forecast Rainfall (inches)
S. of 6° N
6° N to 8° N
N. of 8° N 
February - April 2008
95%
(25.26 inches)
95%
(25.26 inches)
85%
(12.89 inches)
May - July 2008
100%
100%
95%
August - October 2008
100%
100%
100%
Nov 2008 - Jan 2009
100%
100%
100%
Forecast rainfall quantities represent BEST ESTIMATES given the probabalistic forecast for each particular season and station.

source: UOG-WERI