BOGOTA, Feb 27 (Reuters) - Heavy rainfall will cut coffee output in Colombia by 3 percent in the first half of 2018, a drastically revised estimate from a 20 percent drop forecast late last year, the head of the growers federation said, following an inventory count.
In an interview with Reuters, Roberto Velez said that in January, the federation completed a twice yearly national count of beans, allowing it to predict new production levels. On Dec. 20, 11 days before the start of the new bean count, he had expected wet weather to cause coffee output to drop 17 points more.
"Fingers crossed for a good harvest, hopefully in the second half so we finish with a harvest between 13.5 million and 14 million bags," he said last week.
Rain and cloud cover tend to damage flowering and prevents the growth of beans.
In emailed comments on Monday, the federation said the December estimate was preliminary and the new bean count showed the rain's impact "was not going to be as serious as initially thought." It did not offer reasons for the wide difference between the two estimates.
The coffee federation, which represents the interests of 540,000 coffee-growing families, is known for providing the most readily available data on Colombia's output and exports. The government uses its estimates.
Hernando Duque, the federation's technical manager, told Reuters that 2,500 coffee plantations were used in the count, which has a 5 percent margin of error in estimates.
"We think the major weather trends that are coming for Colombia are going to be much greater torrential downpours than they've ever experienced before," said Shawn Hackett, president of Hackett Financial Advisors in Boca Raton, Florida.
Hackett said prior to the rains he expected the crop to be down 3-5 percent from 2017. He now sees a drop of 5-10 percent after prolonged and heavy precipitation during this crop year.
He also expects a steady decline in Colombian coffee production over the next five years due to a forecast for fewer sun spots that he said would increase weather volatility.
Colombia missed its production target from 2009 until 2012 because of wet weather and a tree renovation program that temporarily took portions of land out of production.
More than half a million Colombian families make a living from coffee farming.
Bad weather impacts certain areas more than others. Weather pattern fluctuations attributed to climate change are encouraging growers to leave the more traditional central areas of Colombia where output costs are much higher, and head south, Velez said.
The country produced 14.2 million 60-kg bags in both 2017 and 2016. (Additional reporting by Marcy Nicholson in New York Editing by Bernadette Baum)