First 70 Degree Day in Portland Today

March 30, 2016

4pm Wednesday

Feels like May!  Low 70s this hour at PDX, first time this year!

PLOT_Temps_Metro

How convenient…today IS the average date for the first 70 degree temperature in the Rose City

MarkFirst70_80_90

This has been a well-advertised warm spell with a big upper-level ridge developing just to our west and then sliding overhead mid/late week.  We’ll probably end up around 72-73 today, and tomorrow we should add a couple degrees…maybe hitting 74-76.  Same thing Friday.  So enjoy the warm March/April sunshine…it’s time after a VERY wet winter.

Looking ahead, in general the pattern is warmer than normal for the first week to 10 days of April.  Check out the GEFS (GFS ensembles) from the 12z run showing 6 hourly temperature anomaly.  Most of the time between now and the 2nd week of April it’s above normal.  No huge “heat wave” forecast, but you can spot the current warm period and another one around Wednesday-Friday next week.

GEFS_12z_Anomaly

The ECMWF also shows the 2nd warm period next week, although it doesn’t last very long.  See the spike in 850mb temps on the ensembles next Wednesday/Thursday:

tseries_850t_000-360_Portland

As for rain, models have slowly backed off on shower chances for this upcoming weekend.  Here’s another cool graphic from the WeatherBELL site:

KPDX_2016033012_qpf_240

It shows the last 15 runs of the GFS model…newest at the bottom.  That’s 3.5 days worth of model runs.  Each horizontal row is one run of the model.  Take a look up/down on Saturday/Sunday.  Note that a weak system was trying to come through the Pacific Northwest as of about two days ago.  But now it’s totally gone, thus no rain forecast for our area until Monday.  You can also see that 2nd dry/warm period showing up now next Wednesday-Friday (7-9 days from now).   You can also glean from this chart that the GFS has been very consistent showing showers in the Monday/Tuesday time frame.

To summarize:

  • Unusually warm/dry weather continues through the weekend, but the solid sunshine disappears after Friday
  • For gardeners:  an excellent chance for our soils to dry out through Sunday
  • Finish up those activities by Sunday afternoon/evening, rain of some sort is definitely back Monday/Tuesday
  • The next 10 days look pleasant and a bit warmer than normal as we head into April

Chief Meteorologist Mark Nelsen