A moderate drought on most of Long Island that started in May is expected to persist or worsen through December, according to the U.S. Seasonal Drought Outlook released Thursday.

The drought forecast is based on predicted Long Island weather conditions for October, November and December that indicate a 50-percent chance or greater of warmer-than-normal temperatures, according to the NOAA's Climate Prediction Center, which released the drought outlook.

The averages for those months are 54.3, 45.1 and 35.6 degrees.

Precipitation-wise, the prediction center said there's an equal chance of above, below or right at normal for that time period, with 3.79, 3.67 and 4.06 inches the monthly norms.

Since Jan. 1, Long Island MacArthur Airport, the Island's official site for weather measurements, has seen a 7.84 inch precipitation shortfall, according to the Northeast Regional Climate Center at Cornell University.

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Given that shortfall, even normal or near normal precipitation for those three months -- combined with higher temperatures -- would not be expected to reduce the area's drought conditions, said Dan Collins, seasonal forecaster with the prediction center, during a monthly climate webinar Thursday.

The moderate category is the least intensive of the U.S. Drought Monitor's drought classifications.

While continuing dryness is possible through year's end, the prediction center is forecasting a slightly increased chance of above-normal precipitation for the December through February period, with a slight chance for above-normal temperatures, said Samantha Borisoff, climatologist with the regional center.