By Rod Hill on 2013-02-05
So far this month, there's been only a trace in the rain bucket and forecast charts, which are often too wet, give Portland just 1.62-inches of moisture through the first 20 days of this month.
February average rainfall over the past 30 years is 3.66 inches - an average that ten years ago was 4.18 inches. Over the past 10 years, groundhog month has averaged nearly 1.50 inches below normal. All but one February as seen below-average precipitation.
The period of change is long enough for meteorologists to identify as a mini climate-shift. In fact, the so-called 'Big 4' rain months for Portland's rainy season used to be November through February. That period, for decades, represented roughly half of the cities' annual rainfall and were the wettest four months of the year.
Not any more, in fact March is now the 4th-wettest month of the year with an average of 3.68 inches.
Perhaps the mini climate-shift that catches your eye the most is the increasing trend of wet spring months. April, May and June all have higher rainfall averages then 10 years ago. In fact, recent years have shown little difference in total rainfall between November through February when compared to March, April, May and June.
For now, enjoy a dry day and wonder if this spring will be another soaker.
Mini climate shift set to continue in Oregon