Snow Event Categorys

I have came up with this simple categorization of snow events whenever one happens which makes it easy to write up a report after. Here's the three basic snow event types: Types of Snow Events for NW Oregon- Surprise Shot- This is when snow is not forecasted, but the upper atmosphere is cold enough to cause evaporative cooling. Usually you can catch this an hour before it happens by checking higher elevations close to your area. Sometimes though, the air may be too warm on the surface to change over to snow which may give you a snow/rain mix at 40 degrees. These events typically last about 30 minutes before the air moderates and the snow changes back to rain. Arctic Snow- This is when the temperature is in the 20’s or lower with overriding moisture. It will cause the snow to be very dry and powdery, this is often predicted 2 days in advanced and can last however long the arctic air mass is over the area. It can also lead to blizzard like conditions with blowing snow. This is the least common of snow events for NW Oregon. The Gorge Outflow Snow Effect- The most common of snow events in NW Oregon, the Gorge Outflow determines most of our snow events by the infamous east wind. If a cold air mass is just east of the cascades and we have a low just off the S. Oregon coast, that usually will produce the east winds and filter the cold air into the western valleys. Then the overriding moisture from the low will cause the moisture to start out as snow. These events will last from an hour to all day depending on the amount of cold air pulled in. Once the warm front goes by though, you typically see a warm up and an end to the snow event. Again, pretty simple..hope that helps. Speaking of snow, do we have a chance to see some before the end of winter? Yeah we actually do, but we will wait until next week to make any hard bets on the situation. Take Care.