Tropical weather development in the Atlantic is expected to be below normal for the remainder of the hurricane season, but federal experts are still urging caution as the year's peak storm period begins.

Government meteorologists revised their earlier predictions downward for the 2018 hurricane season, citing ocean temperatures and atmospheric conditions for the amount and intensity of tropical weather formation.

Forecasters put the likelihood of a below-normal Atlantic hurricane season at 60 percent—compared with 25 percent in May—in an updated outlook issued Aug. 9. They pegged the likelihood of a near-normal season at 30 percent and the chance of an above-normal season at 10 percent.

The National Oceanic and Atmospheric Administration now predicts nine to 13 named storms with sustained winds exceeding 39 mph. The agency sees four to seven of those storms reaching hurricane strength, with sustained wind speeds of at least 74 mph, and up to two becoming major hurricanes with winds in excess of 111 mph.

The Atlantic hurricane season began June 1 and continues through Nov. 30. An average six-month hurricane season produces 12 named storms, of which six become hurricanes, including three major hurricanes.

So far, four storms have developed to the point of name status: Alberto, Beryl, Chris and Debby.

Alberto was a subtropical system that developed in late May, making landfall near Laguna Beach, Florida. Chris and Beryl formed from tropical waves in early July and developed to hurricane strength, but remained offshore before dissipating. Tropical Storm Debby developed from a system that formed Aug. 4, breaking up in the central Atlantic five days later.

"The hurricane season is far from being over," cautioned Gerry Bell, lead seasonal hurricane forecaster at NOAA's Climate Prediction Center. "We urge continued preparedness and vigilance."