Here are the graphics I’m using for the evening show…I’m working tonight since I was already scheduled, not due to “SNOWPOCALYPSE 2012: THE REBIRTH” coverage. I’m just kidding, we don’t have crazy out-of-control weather coverage tonight. But some good pictures from the Cascades and Coast Range.
Today worked out pretty well, temps were within a few degrees of 40 most of the day; officially a high of 44 so far at PDX. The showers were quite intense this morning, but there is a weakening trend since around 2pm on the radar. Most likely we’ll see about half of the radar echoes disappear with the loss of daytime “heating” after 6pm too.
Take a look at precipitation forecasts for Portland from several models, these are from 4am Sunday through Sunday evening when it dries out:
12z NAM: .07″
12z RPM: .08″
18z RPM: .04″
12z GFS: .09″
18z GFS: .05-.18″ depending on whether you use TTD or PDX.
If you want snow in the lowlands, that’s the main weather factor working against you the next 24 hours. For this reason, I scaled back the snow totals even in the hills as you see in the graphics above. I would be surprised to see more than a trace of snow officially out at the Portland forecast office.
Monday should be a great day with sunshine the entire day due to cool and dry air filtering in from the north. Not an arctic blast, but a late February chill in the air.
Tuesday is still really up in the air forecast wise. If we get solid precipitation rushing in here quickly in the morning, we could see snow in the air everywhere and sticking even in some spots. If it comes in slowly (like 11am or later) or is very light with a splitting trough, just a cold rain. Something to keep an eye on.
If we don’t get anything on Tuesday, most likely we are done with a chance for sticking snow at the lowest elevations for the year. Wednesday has onshore flow type showers like today except the airmass isn’t as cold, then slightly warmer temps later in the week with no real cold troughs (-6 or below at 850mb) showing up in the long range maps.
Chief Meteorologist Mark Nelsen