Thursday, February 6, 2014

Snowfall opportunities in the coming days

With an Arctic air mass solidly entrenched over the northwest US, we're looking at the potential for snow for the Inland Northwest in the coming days.  As usual, these forecasts are going to be tricky.  So keep checking the forecast to stay up to date.

First, we'll start off with a look at this morning's minimum temperatures in the Pacific Northwest.

Low Temperatures Thursday 6 February 2014

Sub-zero temperatures were widespread in eastern Washington and northern Idaho. There were several locations which reported readings of -20°F, the coldest readings this winter.   Western Montana saw temperatures as cold as -40 degrees!  But notice that it was quite cold in western Washington and Oregon as well.

The first storm is already moving onshore today (Thursday).  Snow is falling over western Oregon, all the way to the coast.  Here's the webcam capture from the Oregon coast in the town of Pacific City.

Web camera showing snow at Pacific City Oregon, 6 Feb 2014

However, this storm will track across northern Oregon into southwest Montana.  This will leave most of the Inland Northwest on the northern fringe of the snowfall.  Below is the current forecast of snow for Thursday night through Friday:
Snowfall forecast for Thursday night and Friday morning (Feb 6-7 2014)

As you can see, those folks near the Canadian border will see the least amount of snow, while locations in southeast Washington the southern Idaho Panhandle will see the most.  The Spokane metro area is looking to get around 1".  The very cold temperatures will result in a light fluffy snow.  That coupled with the cold dry roads means that driving conditions shouldn't be too bad on Friday. However, there is some potential for blowing and drifting snow, especially over the Palouse and southeast Columbia Basin where northeast winds of 10-15 mph could stir things up considerably.  

The next storm will follow a similar track, and will move through the region on Friday night and Saturday.  The chart below shows the expected snow fall from this storm.

Snowfall forecast for late Friday night through  Sunday (Feb 8-9 2014)

After a break on Sunday, a weak front will bring light snow to most of the area on Monday.  At this point, this doesn't look like a big snow event.

Storm number four looks like it will move through the area by the middle of the week.  The computer models don't have great agreement on this system, so our confidence is low.

Throughout all of this, our temperatures will gradually be warming.  The image below gives you an idea of what we're looking at for Spokane.

7-day forecast for Spokane
As the graph shows, by the middle of next week, our temperatures will have returned to near normal for this time of year, which means highs in the upper 30s and lows in the mid 20s.

One thing to note.  Typically in these warm ups after a cold arctic intrusion, the cold air near the surface is tough to scrub out.  This can set the stage for freezing rain.  At this point it's too far in the future to predict where and when this will occur, if at all.  But most likely it would be between Monday and Wednesday of next week.

The outlook through the third week of February suggests the warming will continue with more wet weather. It's quite conceivable the weather we just experienced will be the coldest of the winter. The sun angle is getting higher by the day, while the days are steadily lengthening. By February 20th, the length of daylight will be 10 hours and 38 minutes, a gain of 47 minutes compared to today. 

8-14 day temperature outlook

8-14 day precipitation outlook

No comments:

Post a Comment