After unusually high amounts of rain fell on the Kitsap Peninsula last fall, this summer is starting out with a most unusual pattern of dryness.
It appears that we haven’t had any measurable precipitation anywhere on the peninsula since mid-June. That’s an oddity for dryness not seen in even the driest year on record since 1990, when Kitsap Public Utility District began keeping rainfall data.
Since May 17, Central Kitsap has seen only 1.4 inches of rain, while less than half an inch fell in Hansville during that time period. That’s barely any rain, given that we are talking about nearly two months. Holly has experienced about 2.4 inches in that time — still way low for the rain belt region of the Kitsap Peninsula. And to think that last fall I was contemplating that we might break a record this year. See Water Ways, Oct 27.
I will admit that I used to avoid writing weather stories for the Kitsap Sun. If an editor asked me to write about the weather, I would think for a moment and promise a “much better” story of a different kind. Now, as I try to keep up on climate change, I find myself fascinated with what I can learn from rainfall patterns — including the extremes you see going from south to north on the Kitsap Peninsula.
If you haven’t been around the area much, you may not know that we get more and stronger rainstorms in the southwest corner of the peninsula around Holly, while Hansville at the peninsula’s northern tip may get a third as much rainfall in some years.
Take a look at the pink lines in the charts on this page to see the average over 25-30 years. The scales on the left side of the graphs are different, but the charts show an average precipitation around 30 inches for Hansville in North Kitsap, 50 inches for Silverdale in Central Kitsap, and nearly 80 inches for Holly in Southwest Kitsap.
These charts also show the rainfall patterns in each area for this year with a blue line. Last year, which had above normal rainfall, is shown in orange. And the year that ended with the highest total rainfall is shown in green.
Hansville is especially interesting, because this year and last year essentially kept pace with the record rainfall year of 1999 as spring ended and summer began. In fact, on May 16 of all three years, the total accumulation to date in Hansville was 38 inches, give or take less than half an inch.
After May 16, the three years diverged in accumulated rainfall, and this year’s dry spell makes the blue line as flat as it can get for an extended period. Last year, the driest time came in April, as you can see from the flat section of the orange line.
July and August are typically the driest months of the year, but that can vary greatly by year. I used to tell people that we Puget Sound residents can expect a full three months of summer each year, but nobody can predict when it will happen or whether it will be divided up, say a week here and a week there.
Anyway, as I mentioned on April 1 in Water Ways, we are on a trajectory to exceed the average rainfall this year even if we get no more rain until the water year is over on Sept. 30. It appears our water wells will survive, but we need more rain for the streams to rise by early fall for salmon to increase their numbers.