Climate scientist James Renwick said the rainfall problems could be traced back 12 months, when the region began experiencing one of the strongest La Niña systems on record. Meteorologists are forecasting the lack of rain could continue until December.
The area normally receives 7 to 14 inches of rainfall per month.
The New Zealand government has sent an armed forces C-130 plane to Tuvalu stocked with Red Cross supplies of bottled water and desalination machines.
The nation of Tuvalu has a population of about 11,000, and lies about halfway between Australia and Hawaii. Tokelau, a New Zealand administered territory of 1400 residents, lies 310 miles east of Tuvalu.
While nobody has gone thirsty yet, officials worry about the logistics of supplying everyone with enough water to survive and the potential health problems that might arise. And exactly how the islands will cope in the long-term remains a question mark. Officials are worried the combination of rising water levels and low rainfall makes life on the islands look increasingly precarious.