Is It Spring Yet? | Outside My Window


Honeysuckle leaves in the City of Pittsburgh, 16 March 2019 (photo by Kate St. John)

20 March 2019

Today is the astronomical First Day of Spring when the sun crosses the celestial equator at 5:58pm EDT. But is it Spring yet? It depends on where you live.

The USA National Phenology Network tracks spring across the continental U.S. based on first leaf out conditions for honeysuckle (Lonerica) and first bloom conditions for lilacs (Syringa vulgaris). The plants are non-native, and honeysuckle is invasive, but they make good indicators because they’re early responders to springtime warmth.

Monday’s animated Spring Leaf Index (18 March 2019) shows that leaf out was ahead of schedule through late February but fell behind in northern Virginia, the southern Great Plains, and the Pacific Northwest when cold weather hit in early March.

Spring Leaf Index as of 18 March 2019 (animation from USA NPN)

According to the model, spring hasn’t reached Pittsburgh yet but I’m conducting my own Leaf Out Survey in my neighborhood. I took the honeysuckle photos below on 11 March and 16 March 2019. Both were cold days after a spurt of exceptionally warm weather. The tiny leaves on the right show the effect of 77 degrees F on March 14!

Honeysuckle leaf out, City of Pittsburgh, 11 March and 16 March 2019 (photos by Kate St. John)

Do you have leaves in your neighborhood yet? Is spring on time?

Follow spring’s progress at the USA National Phenology Network. For blooming times click here for the latest Spring Bloom map.

(animated map from the USA National Phenology Network. photos by Kate St. John)