3 Nice Days, then Very Wet!

March 21, 2014

Oregon’s Spring Break has begun and it looks glorious for Saturday, Sunday, and Monday.  We’ll see slight warming over the weekend, then a warming overhead atmosphere combined with offshore flow and Monday will push temperatures up to the warmest we have seen so far this year.

MarkHeadlines_SpringBreak

The GFS, ECMWF, and WRF-GFS show temperatures just shy or at 70 degrees for a high Monday afternoon.  That wouldn’t be unusual because about every other year we hit 70 at some point in the month.  Maybe similar odds to hitting 98-100 degrees in July?  OR, maybe we’ll just top out at 68 as my current forecast shows.  Either way, try to take a sick day Monday to enjoy the warmth.  Because then we turn very wet.

All models are in strong agreement that we’ll be seeing several weather systems Tuesday through at least the following weekend.  The ECMWF shows rain beginning Monday night with no 12 hour period dry for the following 7 days!

salemrain

That graphic shows the actual rain accumulation in blue on the bottom chart and the ensemble average as green; note ensembles are quite close to the deterministic forecast.  The chart on the top shows each individual ensemble member’s rainfall accumulation.  By the way you’ll notice I use Salem instead of Portland since the terrain on the ECMWF seems to shove heavier Clark County foothills precipitation too far southwest into the metro area,  The GFS meteogram shows the same thing; this is the 00z run this evening:

gfs

Probably not such good graphics to use on TV eh?  Might be mildly confusing.

So enjoy the next 3 days, and then hunker down for lots of rain and some windy systems too.  It IS possible to have a weak windstorm this late in the season, but right now I don’t see any real deep lows close to the coast or strengthening as they approach.

On another note, our overnight temps should warm a bit the next two days.  There were record low temps in Pendleton, John Day, and Burns this morning.  12 in late March…that’s chilly!

PLOT_Lows_ORWA

Chief Meteorologist Mark Nelsen