Pacific ENSO Update

2nd Quarter, 2006 Vol. 12 No. 2

FSM Flag Federated States of Micronesia

Kosrae State: There was a very sharp north-south gradient of rainfall across Micronesia during the first three months of 2006, and at the latitude of Kosrae (5.3º N), there was abundant rainfall (60 inches), with amounts falling off to the north (Kwajalein, at approximately 9º N, had only 9.28 inches of rain during these three months.) The 1st Quarter 2006 rainfall values recorded on Kosrae were the highest in Micronesia, and were above normal for this normally very wet island. The 1st Quarter total of 58.76 inches at Kosrae Supplemental Aviation Weather Reporting Station (SAWRS) (located at the airport on the north side of the island) was 119% of normal. At other locations on the island it was even wetter with over 60 inches recorded at Utwa and at Tofol.

Kosrae Rainfall Summary 1st Quarter 2006
Station   Jan. Feb. Mar. Total
Kosrae Airport (SAWRS) Rainfall (inches) 24.94 9.00 24.82 58.76
% of Normal 173% 55% 133% 119%
Utwa* Rainfall (inches) 27.22 10.25 24.73 62.20
Tofol* Rainfall (inches) 30.54 10.00** 28.29 68.83
Nautilus* Rainfall (inches) 25.72 7.67 25.00** 58.39
* Long term normal is not established for these sites
** estimated amount

Climate Outlook:

With ENSO neutral conditions following the earlier weak La Nina conditions this year, the risk of a damaging tropical storm or typhoon would be very unlikely at Kosrae during 2006. The very early stages of developing tropical cyclones may bring some episodes of heavy rain to Kosrae, but these systems should not become tropical storms or typhoons until they are well away from Kosrae.

Predicted rainfall for Kosrae State from May 2006 through April 2007 is as follows:

Inclusive Period
% of Long-Term Average
May - Jun 2006 115%
Jul - Dec 2006 100%
Jan - Apr 2007 110%
source: UOG-WERI