weatherblog

Wet snow possible around lowlands Saturday, Monday

TONIGHT and FRIDAY: A few light showers or drizzle will be possible for the balance of the day and this evening too but we’re on a drier trajectory into Friday’s forecast. With the recent rainfall and surface moisture around, we’ll likely see some fog forming tonight into Friday morning, particularly in valleys, the South Sound and any other typically foggy locations. We should stay above freezing in most locations so I’m not expecting any freezing fog concerns but there will be some frost on windshield and car hoods early Friday. We’ll stay mostly cloudy but some sunshine is possible Friday with highs in the 40s.

The forecast for the weekend into next week is a very tricky one, in terms of snow levels and where we might actually see some snow accumulation. Overall impact to travel in the lowlands still looks fairly low but it will bear close watching.

SATURDAY: The first opportunity will be early Saturday morning with snow levels dropping below 1,000 feet around Puget Sound and possibly down to 500 feet from Everett north and also on the Olympic Peninsula. The weather system coming in will have enough moisture for a slushy inch or two of brief accumulations on these higher hills with possibly some flakes seen mixed with rain elsewhere in the lowlands but probably no accumulation as we’ll just stay a touch too warm. As we get into the late morning hours Saturday we’ll see snow levels rising to above 1,000 feet before precipitation ends from north to south in the afternoon to early evening.

Right now, for Saturday, any issues with snow should be pretty minimal in most lowland locations and even on the higher hills given the brief nature of the precipitation episode, warming temperatures through the day and also ground temperatures that will stay above freezing. It is important to note that temperatures during Saturday’s precipitation (and Monday too) will stay above freezing in the lowlands so any snow that does fall will melt and not stick around or refreeze!

The mountain passes Saturday will be a different story, though, with snow and possibly freezing rain at times starting in the pre-dawn hours of Saturday and continuing into Saturday evening. Snowfall of 3-6 inches can be expected which isn’t likely to cause extended problems unless spinouts occur (and we have seen that already this season.) For that, travelers should check conditions before heading across the mountains Saturday.

SUNDAY: Sunday will be mainly dry but also mainly cloudy. Highs will be in the 40s with lows in the 30s.

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MONDAY: A potentially more substantial weather system arrives late Sunday night and continues through Monday. Just like Saturday’s weather system, temperatures will be right on the borderline for any lowland snow, though the fact that we could have heavier precipitation (which can “drag down” snow levels) poses a greater risk for snow at times in lowland locations on Monday morning. Working against any lowland impacts will be the continued fact that surface air temperatures will remain above freezing and temperatures will warm slightly through the day, turning any areas of lowland snow Monday morning into just cold rain. Still, we’ll need to keep an eye on the forecast as it evolves into this weekend and also any schools that could be impacted Monday morning, particularly up north and in locations above 500 feet elevation.

By Monday midday or afternoon, we ought to be seeing just cold rain below 750 to 1,000 feet in elevation but the mountain passes will get more snow.

LATER NEXT WEEK: I’m broadbrushing a chance of rain or wet high hills snow Tuesday but the chances for lowland impacts from any frozen precipitation should be lower on Tuesday. I’m forecasting just cold rain Wednesday through the end of next week but we’ll keep getting more snow in the mountains – better late than never.

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