All but one day this month has been warmer than average in Washington, pushing its famed cherry blossoms ever closer to peak bloom. Because of the mild weather over the region now and the forecast for more over the next 10 days, were moving up our forecast for peak bloom five days, from March 25 to 29 to March 20 to 24, centered on March 22.
If peak bloom occurs on March 22, it would mark the seventh earliest date on record (since 1921). The date would be nine days earlier than the 30-year average of March 31, and 12 days before the longer-term (1921 to 2019) average of April 3.
Such an early bloom would fit in with many other trees in the area, which are leafing and flowering up to two to three weeks ahead of schedule.
[Winter is over in Washington, although it hardly arrived]
When temperatures surged to 74 degrees Monday, the National Park Service reported the blossom buds had already reached their third stage (out of six), called extension of florets. On average, peak bloom occurs a little more than 10 days after this stage, although the range in recent years between six and 16 days.
In addition, Leslie Frattaroli, natural resources program manager at the Park Service, wrote in an email that the cherry blossom indicator tree was already in full bloom. Typically the rest of trees at the Tidal Basin hit peak bloom about 7 to 10 days after the indicator tree.
The abnormally mild weather, which began in the winter months, has accelerated this years bloom cycle. The cherry trees reached the first stage, green buds, on the 4th earliest date since 2004 (Feb. 28) and reached the second stage, florets visible, just four days later (March 3). Capital Weather Gangs Ian Livingston tweeted the four day interval between the first and second stage was the shortest on record (since 2004).
Mild weather this week, culminating with highs near 70 on Friday, has a reasonably good chance to advance the buds to stage 4, peduncle elongation.
The bloom cycle is then likely to slow between Saturday and Monday, with predicted high temperatures in the 40s and 50s.
But, by Tuesday next week, mild weather returns with highs in at least in the 60s through Friday (March 19), possibly flirting with 70 on some days. This warmth may push the blossoms into their penultimate stage, puffy white, when the flowers are starting to emerge. Typically, peak bloom, the sixth and final stage, occurs a few days later.
Forecast temperatures starting around March 20 become more uncertain, so theres an outside chance the bloom process slows if it turns cooler. Alternatively, if temperatures over the next 10 days end up warmer than forecast, peak bloom could occur a little before March 20. This would be before the National Cherry Blossom Festival, set for March 20 to April 12.
But even if peak bloom occurs before March 20, blossoms can remain on the trees for a week or so, if its warm and dry and winds are light.
The National Park Services peak bloom forecast is March 27 to 30, but we expect that they will soon revise this prediction and move the dates up earlier.