Cherry blossoms are halfway to peak bloom and much sooner than normal
Posted by
prayformojo (aka mayhem)
Mar 9 '24, 17:25
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Jason Samenow
4–5 minutes
The cherry blossom buds at the Tidal Basin are speeding toward peak bloom well ahead of schedule. Mild days and a lack of freezing nights have allowed the buds to progress through the first half of the bloom cycle with unusual haste. Peak bloom could be as little as 10 days to two weeks away, and it would be among the earliest on record.
An increasing concern is that blossoms may near or reach peak at the same time a considerably colder weather pattern arrives. It’s too soon to know whether it will be cold enough to damage the blossoms, but the weather pattern bears watching.
On Friday afternoon, the National Park Service announced the blossoms had reached Stage 3, or “extension of florets.” This means the little flowers inside the blossom buds are growing. This stage marks the midpoint of the bloom cycle and, on average, peak bloom occurs about 10 days to two weeks later. However, when it’s very warm, sometimes peak occurs as soon as a week later and, when it’s cold, it can take up to 15 to 20 days from Stage 3.
Remarkably, it took the buds only six days to progress from Stage 1 to Stage 3 this year — the fastest rate in at least the past 20 years. Mild weather is the reason. March, so far, is averaging more than 8 degrees above normal.
The weather will actually turn chillier through Monday. Highs are only predicted to reach 50 to 55 Saturday and Monday and 45 to 50 on Sunday. Lows will probably dip into the 30s Sunday and Monday nights, but remain above freezing. So the buds may not advance as fast as they have in recent days. Still, last year it took the buds just four days to go from Stage 3 and Stage 4 — or “peduncle elongation” — with temperatures similar to what’s predicted through Tuesday. So it’s not unreasonable to project the buds could hit that stage by around then.
And Tuesday will also mark the start of a major warming trend. Highs could top 70 between Wednesday and Friday. That could very quickly move the buds to Stage 5, or “puffy blossoms” by next weekend (March 16 and 17) — the final stage before peak bloom. Typically, peak bloom occurs with three to five days of Stage 5, but, in some years, it has taken as long as seven to 10 days, mainly because of cold weather.
Assuming the buds reach Stage 5 by March 16 or 17, peak bloom could realistically occur any time between March 18 and 27. That window more or less coincides with the peak bloom dates projected by the Capital Weather Gang and the Park Service. Our predicted peak bloom forecast is for between March 19 and 23, while the Park Service is calling for March 23 to 26.
Which forecast is closer to accurate will depend on the weather starting around that March 16-17 weekend. Computer models tend to agree it will start to turn chillier around that time. But it’s highly uncertain how much it will cool down and how fast. A modest and slow cool down could mean a peak bloom as soon as March 18. But if an intense blast of cold air moves in quickly, it could stop the bloom progress in its tracks.
A serious concern is potential for cold air to damage the blossoms. Once they reach Stages 4 and 5, the flowers are further developed and more sensitive to cold. In 2017, buds that had reached Stage 4 were badly damaged by snow and temperatures that plunged into the 20s.
Once peak bloom occurs, the blossoms can remain on the cherry trees for another week or so if it’s warm and winds are light. But in some years, petals fall off more rapidly because of wind, rain or frost.
This year’s peak bloom should coincide with the very beginning of the National Cherry Blossom Festival, which runs from March 20 to April 14.
The likelihood of another early bloom fits into recent trends fueled by human-caused climate change. The average peak has advanced about six days over the last century, from April 4 to March 30. Each of the last four years has seen peak bloom before March 29. Last year, peak bloom was on March 23 — more than a week early.
Stay tuned for more cherry blossom weather updates as this (fast) journey to peak bloom continues.
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