WeatherWatcher: Possible snow event to come

1. The week ahead: showers, snow and rain both, nothing major yet, but it could be.
2. Last week highlights: lots of rain!
3. Last week's weather data.

The week ahead:

So as I mentioned last week, we have favorable conditions for a possible snow event to strike. We got a taste of this over the weekend, but it wasn't as bad as it could have been, or could be. That being said, here's the deal:

We have a lot of cold Arctic air built up in British Columbia, Canada, which provides a very potent source of snow generating weather for us. We have a storm track right now that is generally taking moisture-laden Pacific storms right through the middle of Washington State. 

A daily shift happens all the time in how far north, or south these low pressure centers and troughs track. We are flirting with the freezing point in temperature, while maintaining the inflow of moisture off of the Pacific Ocean. 

It looks like we will flip back and forth between rain showers and snow showers for the remainder of our week. The biggest potential is Tuesday afternoon/evening. Shoreline and Lake Forest Park in particular are in the bull's eye of a Puget Sound Convergence zone that all models are indicating will develop. This will bring the snow level down to sea level in this convergence band. 

Here's where it will keep you guessing. Tomorrow morning will start out as rain showers, maybe with snow mixed in. Tomorrow evening colder air may filter into the region, at the same time this convergance zone may develop. If all this happens at the right timing we will receive a pretty significant dose of snow, to the tune of 1-4 inches, maybe more.

Due to the uncertainty of the balance between the cold air, and the warmer Pacific storms, it is difficult to say how the rest of the week may go. Most consistently we are looking at rain showers at times, and snow showers at times, as some systems pass to the south of us, and other systems pass through the middle of us for the week. If there is a slightly bigger shift southward, we will get much colder with more snow.

Currently there are no winter weather advisories or watches right now, but I suspect this may change, I will keep my twitter updated as things change, as well as try to send updates here.

Keep in mind that most mornings this week we will have temperatures below freezing, so watch out for ice in the roads during the morning commutes.

Last week:

As mentioned, we would be wet. We received 1.62 inches of rainfall, which was the most significant weekly rainfall all month. This winter has been drier than normal, despite the moderate La Nina.

Last week's data:

• High temperature: 48.7ºF (Tuesday)
• Low temperature: 34.2ºF (Thursday)
• Rainiest day: 0.57 inches (Tuesday)
• Total rainfall: 1.62 inches
• Warmest day: 47.0ºF (Tuesday)
• Coldest day: 39.2ºF (Sunday)
• Average temperature: 41.9ºF

Warmest and coldest days are based on average temperature of the entire day, starting at midnight. All other averages are based on the whole week. All weather data unless otherwise noted is sourced from Carl's Shoreline Weather Station.