Quick Late Evening Post

December 29, 2014

Cold air mass definitely not as cold as models were showing in the past 24-48 hours.  So I raised 7 Day forecast numbers again…to 35/37/38 degree highs the next 3 days.  That might be too low.  I could see a 37 degree high at PDX tomorrow.

Wind isn’t too wild this evening, as models showed.  They have nailed that part of the forecast well.  I see PDX just peaked at 41 mph but just about all other locations are much weaker.  I expect most gusts will stay below 35 mph.  PLOT_Wind_Metro  Interesting to note that PDX is stronger than Corbett AND Vista House at this hour!  That’s very rare.  I’ve been watching the snow blow around on our Skibowl Camera this evening…Brrr!  Check out the  temps:  PLOT_Temps_MtHood_CamOnly

Because of the cold temps and wind, the NWS has a Wind Chill Warning out for the higher parts of the Cascades, this includes Tuesday so be careful and cover all your exposed skin if you’re headed up around 5,000′ or so on the open slopes.

MarkWarnings_WindchillCascadesText

Other than the cold and breezy wind, some great sunshine now looking likely through Friday.  Beyond that ridging seems to stick around off/on through the middle of next week.

Chief Meteorologist Mark Nelsen


ECMWF Monthly Run

December 29, 2014

Twice a week the ECMWF model is run out to 32 days and sometimes we can glean some basic info about the very general weather patterns ahead.  And sometimes we can’t…

Here are the four weekly averages of 500mb heights, with the anomaly in color.  Blue is lower than average and red is above average.

It’s very good the Cascades had a great dumping of snow because the pattern continues to look somewhat pathetic through January as ridging returns.

Week 1 & 2:

500za_week1_bg_NA

500za_week2_bg_NA

You can see ridging through early next week and then some cooler troughs offshore.  That should give us at least some sort of weather action later next week.  It’s supported by this morning’s ECMWF time series showing temps dropping (in the mountains) later next week:

tseries_850t_000-360_Portland

Week 3 & 4:

500za_week3_bg_NA

500za_week4_bg_NA

That annoying ridging returns overhead and also to the north.  The “El Nino” pattern of storms into California doesn’t show up like it did a week or two ago…that’s interesting.   I don’t have any other thoughts than that.  If these maps are correct, January could be a slow weather month.  We’ll see.

Chief Meteorologist Mark Nelsen