Snow In Hills Thursday A.M.

April 20, 2011

A very chilly airmass moves into the Pacific Northwest briefly later tonight and tomorrow.  A burst of showers late tonight and before 10am could bring sticking snow down around 1,000′ in the foothills of the Cascades and Coast Range too.  That means ANY OF US could see snow mixed in with the rain later tonight through tomorrow morning.  Not a whole lot of anything, but a nice curiosity for late April don’t you think?

The picture above is an oldie but I still love it.  It’s from Jerry Kinney.  The top photo is the mill pond in Vernonia on April 19, 2008.  It was the last dusting of snow down around 1.000′ during that cold La Nina Spring (like this year!).  The lower picture was taken 3 weeks earlier in 2007.  Notice how delayed the vegetation was in 2008 compared to 2007.  Of course we have similar conditions this year as well.  And Vernonia could easily see a dusting tomorrow morning.  The sticking snow level tomorrow afternoon will jump back to around 3,000′.

There is a bright spot in the forecast…we get offshore (easterly) flow and a warmer airmass Friday and most of Saturday.  We should actually see above average temps Friday and Saturday.  The beginning of a rainy spell arrives by sunset Saturday.

By the way, there has been some incorrect information floating around weather circles the last 30 days about latest snowfall in Portland.  Part of the confusion is the fact that in the past snow and hail were BOTH included in daily “snowfall” totals.  Obviously that means it could snow in early October or May!   Here is the pertinent info:

1. Measurable snowfall has never been recorded at PDX in April…those records go back to 1940, or about 71 years.  The latest measurable snowfall at PDX is March 20, 1995 (.4″).

2. Measurable snowfall HAS been recorded in downtown Portland in April, 5.4″ on the 1st back in 1936, and 1.4″ in April 1933 as well.  Otherwise less than .30″ in a few years in the late 1800’s and early 1900’s.

Chief Meteorologist Mark Nelsen