Very Dry December and Lack of Snow.

This December has been very dry so far, PDX has only received 0.01 inches of rain so far this month compare that to the December average of 5.49 inches. But it's not only us, the eastern half of the county has had very little snow as well.

The image below shows the total snow on the ground on December 12 (yesterday)

But look at the same time last year.

A really big difference!

Now whats the reason for this? The reason is there is two big upper level ridges (circled in red) are allowing the cold and moist air(yellow arrow) to ride over the U.S and only allowing small troughs (which carry cold air) to drop down.     

Tomorrow: In the previous post I mentioned a chance of snow, well now its pretty much gone as tha low pressure will go to far north a will be very weak so the only chance of frozen precipitation will be in the gorge.

The image below is the 12z GFS-WRF showing the weak low to far north and the lack of cold air.

Later this weak: Yet again the high pressure will build back over us giving us yet more dry weather and no snow for the cascades.

The image below shows the high pressure over us on Friday.

For skiers and snowboarders:

  Timberline forecast:

 Wednesday: A 30 percent chance of snow after 4pm. Mostly cloudy, with a high near 36. West southwest wind between 8 and 14 mph, with gusts as high as 21 mph. Little or no snow accumulation expected. 

Wednesday Night: Snow likely, mainly after 10pm. Cloudy, with a low around 23. Southwest wind between 18 and 20 mph, with gusts as high as 30 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 3 inches possible. 

Thursday: Snow showers likely, mainly before 10am. Cloudy, with a high near 31. West wind around 18 mph, with gusts as high as 28 mph. Chance of precipitation is 70%. New snow accumulation of 1 to 2 inches possible. 

Thursday Night: A 30 percent chance of snow showers, mainly before 10pm. Mostly cloudy, with a low around 21. West wind between 6 and 9 mph becoming calm. Little or no snow accumulation expected. 

Friday: A 10 percent chance of snow showers before 10am. Partly sunny, with a high near 36. 

Friday Night: Mostly cloudy, with a low around 22. 

Saturday: Mostly cloudy, with a high near 35. 

Thanks for reading 

-Michael