NOAA 99-044
Contact: Randee Exler


With large portions of the Mid-Atlantic reeling from the three H's of an early summer -- humidity, haze, and heat -- mother nature has thrown another climatological woe into the region: drought. National Oceanic and Atmospheric Administration forecasters predict short-term relief in sight, with rain coming and cooler temperatures coming as early as next week, but a resurging La Niña may contribute to drought conditions throughout the summer and possibly into the fall.

"For farmers in this region, this makes the third consecutive year of drought. Recent heat and lack of rain have quickly worsened the dryness. Rain in the next week or so may bring short-term relief, but a resurging La Niña could extend the drought into the fall," said D. James Baker, under secretary of commerce for oceans and atmosphere and NOAA administrator.

The recent heat and the poor showing of rain may be the result of a "blocking ridge" of high pressure that is pumping the three H's up from the south and fending off rain from the drought areas, said Ants Leetmaa, director of NOAA's Climate Prediction Center.

La Niña, the climatic opposite of El Niño, is defined as cooler than normal sea-surface temperatures in the tropical Pacific Ocean that impact global weather patterns. The La Niña is currently weak but forecasts predict that this condition may strengthen this summer.

"While La Niña may contribute to warmer, drier conditions in the Mid-Atlantic, La Niña also may be a factor in bringing this dryness to an end," Baker explained. "NOAA forecasts an active hurricane season this year as a result of La Niña. Should tropical storms bring additional rain to the mid-Atlantic, dry conditions may end."

"NOAA's long-range forecasts show no long-term relief for the drought this summer," said Leetma. "Normal rainfall amounts this summer may still keep this area below normal conditions. Rainfall during the past six weeks in the Washington, D.C., area have totaled only about 1 to 2 inches where around 4 to 6 inches would be expected."

Though dryness is a concern through the Northeast as well as southward into northern Florida, the only other area in the country where drought conditions are as bad or worse than in the Maryland-Northern Virginia region is Georgia and northern Florida, where rainfall since late January has been below normal. Lingering drought after an abnormally dry winter continues over parts of the Southwest, especially southwestern Texas and much of Arizona.

"The drought in the Southwest is consistent with the La Niña pattern we predicted months ago, but in the Northeast, the average levels of precipitation we expected were pushed about 500 miles to the west," said Douglas LeComte, a drought specialist at the Climate Prediction Center, adding that these conditions helped produce the storms that brought severe weather to Oklahoma and Texas where tornadoes wreaked considerable havoc.

Many parts of the country are experiencing climate extremes. "While the East is suffering from heat and drought, the middle of the country is super wet and California is unusually cold," Leetmaa said. "There was also an unusual June snow in Nevada."

While we think that short-term relief is possible, the longer-term hydrologic drought conditions will persist unless we experience a major tropical storm or hurricane, and we may be talking about drought into the indefinite future," Leetmaa added.