Seattle breaks another record but rain finally lurks on horizon

Seattle breaks another record but rain finally lurks on horizon
The clouds are back in Seattle, and the rainfall is but a few days from returning as well. (Photo taken Oct. 9, 2012, courtesy of Puget Sound Clean Air Agency Visibility Camera)
SEATTLE -- The historical dry stretch of weather in Seattle has claimed yet another record, but by this time next week, thoughts of dry weather will be long forgotten as our typical October rains are set to arrive with gusto.

Until they arrive though, our erasers will continue to get a workout in obliterating current records for dry weather.

The latest casualty? The record for driest 80-day stretch of weather. That was actually set Monday when the day finished dry and the city had only accumulated 0.07 inches of rain since July 20. The old record was 0.08" set in 2006. But don't let the ink dry on that one, because we'll break this infant record at the end of Wednesday when we shift the 80 day period from July 22 to Oct. 10 and reset the record to 0.03".

How little rain is 0.03 inches? We can count our rainfall in minutes. In the past 79 days, Seattle has seen actual light rain for just 249 minutes -- or 4 hours and 9 minutes (not counting drizzle). Believe it or not, Seattle averages about 86 hours of total rainfall in the three-month period of July though September (65 hours for just August and September) -- and that is measurable precipitation. If I take out the rain that didn't measure this summer, Seattle had 174 minutes of measurable rain, or not even 3 hours.

But after days, and weeks, and months, and nearly an entire season of sunshine, there is finally an umbrella at the end of the tunnel. Forecast models for the first time since Ichiro was shipped to the Big Apple show an honest to goodness rain approaching Seattle. And we're not talking this 0.01" streak-busting-on-a-technicality-stuff. We're talking actual puddles.

The first of four successive weather systems is due to arrive late Thursday into Friday. It's not a soaker just yet as the first storm to bust through such a strong ridge of high pressure is usually the sacrificial lamb. But it'll be enough to at least clear the cobwebs out of Sea-Tac's rain gauge. We expect light rain to continue through Friday.

A second system races ashore on the first one's heels on Saturday bringing steady rains once again.

Mother Nature might give surprised, water-logged Seattleites a break on Saturday evening and night, but then smacks us good with what is looking like a very wet storm Sunday coupled with a second one on its heels for Monday. These two have tapped into a bit of tropical moisture and could be pretty wet. In fact, early models suggest roughly 1.00-1.25" of rain in total Friday-Monday accumulation in Seattle. That would be more rain in four days than we've seen since the first of July through now.

The expected rains will likely prevent us from breaking any additional extended dry-period records. The 85 day streak is 0.10" (2006); 90 day is 0.20" (2006); 100 day is 0.38" (2006) and 120 day is 1.19" (2002). (July 19 this year has 0.60" of rain to really thwart those records). Our current 100-day accumulation is 1.07".

With the return of the rains, the Washington State Patrol is warning all drivers to take extra care on the roads when the rains first begin. Long periods of dry weather lead to accumulations of oils on the roadways and they tend to be very slick in the initial hours of an inaugural rainfall. You might also check your windshield wipers that haven't really been used since before people were lining up the floats for the Torchlight Parade.

Extended forecast models do indicate perhaps another dry period as we near the end of the month. But we're pretty sure we can at least put away the erasers for now.