Ticker for February 24, 2017

                
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February 24, 2017  February 24, 2017  February 24, 2017  February 24, 2017


Thar she springs!




Forget what you feel today. Remember what you felt yesterday, and the day
before that, and the day before that...and so on, and so on (Faberge Organic
Shampoo commercial reference...GOOGLE IT, YOUNGSTERS!).

Today



Before today



So yes, I'm going with spring. February is running 5-6 degrees above normal
already, which puts it in March temperature territory, which is also the start
of CLIMATOLOGICAL spring. And that first graphic, the Spring Leaf Index Anomaly
map from the National Phenology Network, shows spring arriving up to 20 days
early across much of the Southern U.S. east of the Rockies. And then we have the
actual spring leaf index itself, which shows locations that have reached the
requirements for spring based on the behavior of plants and recent temperature
conditions.



Here's a more coherent explanation from the National Phenology Network.

"The Extended Spring Indices (SI-x) are models that scientists have developed to
predict the ?start of spring? at a particular location. Using historical
observations of the timing of first leaf and first bloom in cloned lilacs and
honeysuckles, as well as daily observations from nearby weather stations,
scientists have been able to determine the weather conditions that precede
general spring leaf-out for a wide range of plants. Like many other deciduous
plants in temperate systems, these plants put on their leaves as temperatures
warm in late winter and early spring."

The danger, as discussed in a previous Ticker, is what happens if one of those
bigtime March freeze events, which aren't uncommon, comes along whilst all
these plants think it's spring? Still safe for awhile, it appears.





Forget the calendar, listen to the plants, if not the Mesonet temperature data.

Spring has sprung! Any cold weather now we'll just consider a nasty anomaly.

Gary McManus
State Climatologist
Oklahoma Mesonet
Oklahoma Climatological Survey
(405) 325-2253
gmcmanus@mesonet.org