DC Cherry Blossom Alert: Major Delay To 2018 Bloom

The National Park Service is pushing back the projected peak bloom of the cherry blossoms for 2018 by a full week thanks to recent temperature data. NPS is now predicting the peak bloom period will happen March 27-31 instead of March 17-20, the service said in a statement.

The average peak bloom happens March 31, according to the agency.

"While the mathematical models still show the blossom reaching peak on March 18, this week’s cooler than forecast temperatures have necessitated moving the projection to the last week of March," NPS said.

Peak bloom is defined as when 70 percent of cherry blossoms on the Tidal Basin are blooming.

"The most likely time to reach peak bloom is between the last week of March and the first week of April," according to the NPS website. "Extraordinary warm or cool temperatures have resulted in peak bloom as early as March 15 (1990) and as late as April 18 (1958)."

The NPS noted that predicting peak bloom is "almost impossible" more than 10 days in advance because weather conditions can have a big effect on the timing.

"The Yoshino trees typically bloom for a period of several days. The length of the blooming period depends on weather conditions," the NPS added. "Cool, calm weather can extend the length of the bloom, and a rainy, windy day can bring an abrupt end to the ephemeral blossoms. A late frost can prevent the trees from blooming at all."

The National Cherry Blossom Festival kicks off March 20 and ends April 15.

Image via National Park Service