The Big Picture: Warm, Cool, Warm Next 16 Days

January 26, 2016

3pm Tuesday…

Time for a look at the general weather pattern.  During the past 30 days the West Coast has slipped into a much more typical El Nino pattern with a bit drier than normal weather north of Oregon and wetter than normal down in northern/central California with most jet stream energy directed to our south.  Sytems have been quite weak (splitting jet stream), but still coming inland with enough frequency to boost our rainfall to average or a bit above in western Oregon.  Cool colors are wetter than normal.  Parts of central California have seen almost double the typical January rain/snow.

anomimage

We haven’t seen much rain in far southern California…they would probably like some more down there.

Temperatures have been a bit cooler than average across large parts of the West.  We started very cool here in Oregon but now are moving above average the last few days of the month.

anomimage (1)

We’ll end up a little above normal, but not like the 3 degree warm anomaly last month.

Looking ahead to the next 2 weeks…

  1. No sign of an arctic blast for the Pacific Northwest on any model.
  2. Rain should be near normal.
  3. There is no obvious “snow pattern” in the lowlands the next 14 days.  Except for one 24 hour period;  snow levels will be quite low from Sunday night through Monday .night.  But it looks like just dry to me.  That’ll be something to keep a close eye on.
  4. Mild temps continue before that time and return about 10 days from now.

 

Models have been doing very well (forecasting big picture) lately and are in excellent agreement on pattern changes over the next two weeks.  Warm ridging over us now (it rained at the ski resorts today), then a cold trough over/east of us from Sunday through sometime later next week.   Note the ECMWF 500mb height anomaly Sunday; some overdue chilly air.  It’ll feel like January again:

ecmwf_sundayanomaly

This is not a very wet pattern and sure enough the ECMWF is basically dry from Sunday through late next week:

ecmwf_meteogram

The latest GFS (18z) isn’t nearly as dry, but not exactly a soaker either for next week:

gfs_18zmeteogram

The first week of February will be cool though…note those high temperatures drop about 10 degrees from what we’re seeing now.

Then ridging or at least flatter westerly flow returns for the 2nd week of February.  The 500mb height anomaly from ensembles from the ECMWF/GEM/GFS models today for February 10th.  Actually the GEFS is a 5 day average ending on the 10th:

Since I haven’t shown enough maps, here are the 4 weekly ensemble charts from Sunday night’s ECMWF run.  They look “ridgier” in the last two weeks and could be quite warm (fork time).  That said, the actual operational run showed a very chilly airmass over us around Valentine’s Day and beyond with northerly flow.  It showed the ridging farther west.   We’ll see.

Chief Meteorologist Mark Nelsen