March 28, 2020

An Encouraging Weather Forecast

We all need some good news and I will give that to you. 

The weather is going to improve by next weekend here in the Northwest.  Much warmer and even some sun.

But there is also some bad news....we will have to get through a cool/cloudy period first.

Let's face it.  It has been cool and murky this week, a situation that heightened the stress of all the virus news.  Below are the temperatures at SeaTac during the past two weeks, with the normal highs and lows plotted.  Our daily maximum temperatures have been well below normal the last six days.   Like 5-10F below normal.  Plus lots of clouds and light rain.

Tomorrow will be similar and then a much stronger system, with real rain, will hit Monday, associated an unusually energetic upper level trough (see upper level map for 5 PM Monday).   If this was January, we would be worried about lowland snow with such a pattern.

Fortunately, as the week progresses an upper level ridge of high pressure will build along the West Coast and temperatures will rise.   To warm you up, here is the latest forecast for high and low temperatures at SeaTac based on the European Center ensemble forecasting system (running their model many times and taking the average).  High temperatures climb roughly 10 degrees between this weekend/Monday/Tuesday and later in the week.  You will notice that.

The National Weather Service GEFS ensemble of many forecasts shows a cooling trend for a few days, following by warming (see below).  Each forecast is plotted with a line and the black line is the average of all of them.   Warming towards 60F by April 4/5.  

 Southern California will warm into the upper 60s to low 70s....perhaps high enough to slow down the coronavirus there.  Also clearing skies and progression into spring will produce higher ultraviolet

radiation values along the southern tier of the U.S.:  not good news for the virus, which can be degraded or killed by UV.  Below are the forecast UV index for Sunday and Wednesday.  Big improvement over the western U.S.

This is a good time to plant your spring/cool season veggies if you have a garden.  That is my plan this afternoon!


  1. I love the positive news, thanks Cliff.

  2. Really? Because right now it looks like showers/rain next week.

  3. Cliff,

    I'm ready for warmer temps and sunshine. Fortunately, the garden is starting to show signs of life.


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