ECMWF Ensemble Maps & Warm Rain Ahead

January 12, 2015

It’s Monday afternoon, which means 4 maps (1 for each week) from the ECMWF ensembles that take us through the first week of February.  Geez, is February just a few weeks away???  They show the 500mb height and anomaly for each of the next 4 weeks.  This is from last night’s run.  Also, more bad news for skiers; Hoodoo has now closed after just under two weeks of skiing there.  And the important MLK weekend coming up appears to be at least a partial washout.  Models have been trending higher and higher with snow levels.  Aim for Monday, although Sunday may not be bad at the higher parts of the open resorts.  I don’t see any snow at Government Camp until next Monday, and even then it may be just a dusting as cooler air arrives.

Week 1…now through Sunday, ridging overhead the next couple of days and then it gets squished by a strong westerly jet approaching the Pacific Northwest.  You can see a strong trough to our west, but it never moves inland.  As a result we get surges of rain Thursday-Sunday in the southwesterly flow.

500za_week1_bg_NA

Week 2…late this Sunday through all next calendar week…Surprise!  The ridging bounces back over us, mainly dry and not much happening.  With the ridge slightly to the west, we get cool easterly wind most likely.  This takes us through the 25th.

500za_week2_bg_NA

Week 3…the ridge retrogrades (moves west an north).  If so, this would be the time when we could get a shot of cold air from the north on the backside of the ridge.  Maybe.  So 2-3 weeks from now we might see some arctic action on the maps to get us all worked up.  This takes us to February 1st.

500za_week3_bg_NA

Week 4…first week of February.  Can’t quite tell what’s going on exactly but the troughing is getting  quite strong across the Eastern Pacific again and it could be turning very wet with this pattern all along the West Coast.

500za_week4_bg_NA

Remember as always that this is just one monthly run of the ECMWF, but it’s annoying that a strong ridge keeps wanting to pop up over/near us for the 3RD WINTER IN A ROW!  No anger there, just annoyed.

Short term, we have east wind picking up tonight through late Wednesday.  Easterly gradient peaks around 8 millibars through the Gorge tomorrow afternoon and night.  That should be enough to clear out any fog that develops overnight here in the metro area.

I’m surprised again at how warm the Thursday-Sunday systems are…much like we’ve seen so far this winter.  850 mb temps between +2 and +7 during the whole period means no snow below 5,000′.   The snow level should move up and down between 5-7,000′ through the weekend.  Right now it appears Saturday could be the worst with a rain out at both ski areas on Mt. Hood.  Wy’East is getting a nice winter coat this year up top, but he’s not looking so good down at the bottom.

Remember the good old days when we could have a week or two of snow levels between 1,000 & 3,000′?  I think it was the winter of 2007-2008 when for two months (late December to late February) I never forecast a snow level HIGHER than 4,000′.  We haven’t seen consistently low snow levels since the winter of 2011-2012.  Yikes…

If you’re looking for a good snowstorm here in Portland, that’s not in the cards unless we get some of that cold air+moisture between weeks 2 & 3.  We still haven’t seen measurable snow so it’ll be interesting to see if we end up with a “zero” winter.  Quite possible after the overachieving 8″ last winter.

Chief Meteorologist Mark Nelsen