WeatherWatcher: The S Word is back, just when you thought winter was done

A strong cold front is moving through the region tonight, bringing steady rain and cooler air with it. The real story is what comes behind this cold front. The upper levels of the atmosphere are cold enough behind this front to bring snow levels generally down to the 1500-2000ft level. We will also have a convergence zone set up, a very strong and persistent one. Most wind models seem to show that it will be strongest right over Shoreline and Lake Forest Park. South Snohomish County may be getting some of the action too. This convergence will pick up tomorrow mid-morning-afternoon and continue into tomorrow night. 

Now, because the air is cold aloft (upper level air) if the convergence stays to one area, it could generate some lightning during the afternoon hours, and bring the snow level locally down to almost sea level. Wet snow, with accumulations are possible, but the chance is slight. If any wet snow does fall and accumulate it will be short lived, sticking around at most for a few hours. A weak high pressure system is moving through Saturday night that will clear out the weather into Sunday and bring some slightly warmer temperatures. This weather has even prompted the National Weather Service of Seattle to issue a special weather statement on the topic.

Bottom line: It will be wet Saturday with the chance of thunderstorms, convergence over the area, with heavy precipitation. Some of the heavier stuff could fall as hail, which could cause accumulations of 1 or more inches. Additionally the chance that the snow level locally comes down to sea level could bring snow accumulations as well, though it will be very wet snow. Get ready for another wild weather day Saturday.

Also, I wanted to add that this is not the first time a convergence zone storm has brought snow to the Shoreline area in April, as I mentioned in my previous report we had a good 2 inches or so of wet snow fall on us April 18, 2008. That weather pattern was not unlike the one we will have tomorrow.

Longer range shows another weaker storm front moving through Monday for another round of rain, some clearing mid week, and another front around the next Friday time frame.

For current weather conditions and updates, see http://www.shorelineweather.com