Sometimes clouds are simply plain scary. Dark, ominous and threatening.
Just prefer it was on Saturday night time round 7 PM from Seattle northward.
I used to be at Magnuson Park in north Seattle simply earlier than Eight PM and a noticed this line of low-hanging clouds and it was clearly raining….actually onerous…behind them.
My canine began to drag on the leash. She wished to go residence. Now.
Now I’m a meteorologist and, in fact, I’ve a climate radar app (Radarscope) on my smartphone. I pulled it out, and I concluding my canine knew what she was speaking/barking about. Wow…there was a line of robust echos prolonged from Seattle to the northeast. And my location (the blue circle) was proper in entrance of it. Time to run. Fast.
The Seattle SpaceNeedle Pano cam confirmed the road approaching from a extra southern vantage level, beginning at 7:20 PM and ending round 8:20 PM. Pretty scary.
Torrential downpours, with small hail combined in, accompanied the passage of this ominous cloud line, with some locations getting a half-inch to an inch of rain in 30-45 minutes. As the road handed, the winds turned from southerly to northerly and temperatures dropped 5-10F.
Here are the precipitation totals from four to 11 PM Saturday. The precipitation minimize off simply south of downtown Seattle with round .four inches in most areas however as a lot as 1.77 inches close to Lake Stevens. Impressive.
So what was occurring?
The reply: a powerful instance of our outdated good friend the Puget Sound convergence zone. Westerly (from the west) air from off the Pacific break up across the Pacific and the got here collectively (or converged) over Puget Sound. This low-level convergence resulted in pushing air upwards, releasing convective showers. Interestingly, with all the extraordinary rain, there was no lightning and thunder. We want to clarify that.
The 7 PM winds confirmed the convergence zone clearly, with southerly circulation within the south Sound and northern winds to the north.
The seen satellite tv for pc image simply after Eight PM exhibits the convergence zone clouds…tall sufficient to have shadow on its japanese facet.
Why no lightning? It seems that though there was heavy rain, the clouds weren’t that prime, with the echo tops solely attending to 15-20 thousand toes. East Coast people would chortle at such wimpy showers. But there was intense low degree convergence, robust upward movement with the convergence zone and a moist air mass….a lot to present us heavy rain.