Mom's local paper reports
that the leaves in Bristol, Tennessee, are a full month ahead of
schedule. The only leaves we have here are tiny fresh growth on
multiflora rose, autumn olive, and Japanese honeysuckle. But I can
gauge spring's advance based on the pear buds (breaking open for about
a week now) and the gooseberry leaves (which have been pushing gently
out of buds for a little longer than that).
Based on those two
metrics, I figure the beginning of March 2017 is roughly
contemporaneous with:
So we're not a full
month ahead of schedule (unless you measure us by 2015), but our plants
are precocious by at least two
weeks. I guess the question becomes --- do we push our planting
calendar up an equal amount or figure there will be sudden cold spells
up to our usual frost-free date and hold the usual line?
I was just commenting to a neighbor that I felt here in NE TN we were about two weeks ahead of schedule for Spring's arrival. Bristol, VA/TN might be ahead because of all the concrete absorbing the solar heat and then radiating it back out. That's true of all cities.
Where I am, I think in my microclimate I'm about two weeks ahead of schedule this year. I notice that you're in, what I will "euphamistically" call a "holler" (smile) and that microclimate might be why you're dates of Spring's arrival is so erratic.
As far as Spring's arrival coming earlier and earlier each year, apparently the US Geological Survey has a map showing how early Spring's arrival is this year. http://www.vox.com/science-and-health/2017/2/28/14761788/early-spring-map
It also noted in the article that "As the USGS points out, scientists have known for some time that “climate change is variably advancing the onset of spring across the United States.” It’s one of the (many, many) indicators of a warming planet. “These findings are consistent with the fact that the instrumental record shows that 2016 was the hottest year ever recorded for the globe, and that it was the third record-breaking year in a row,” USGS notes."