Wetter than Normal April to be Followed by a Very Dry Start to May

It is not unusual to have a very dry period sometime during the first half of May....and this year won't disappoint.   Particularly, after April ended up wetter than normal over the Northwest.

The precipitation departure from normal over the western U.S for the past 30 days, shows that most of Washington and Oregon enjoyed above-normal precipitation last month (green and blue colors) 

Seatttle-Tacoma Airport, for example, ended up with about an inch above normal (purple is observed, cyan is normal in the figure below)

But there will not be any rainfall for many days now due to the development of a major ridge of high pressure over the eastern Pacific.

The UW model shows dry conditions during the next week over most of the Northwest, with the exception of  a few light showers over the north Cascades.  More rain in California.

The origin of this dry bounty?  A very persistent ridge of high pressure over the eastern Pacific.  Here is the forecast upper level map (500 hPa, about 18,000 ft) for Friday evening.  Major ridge over the eastern Pacific, with a low center to the south.   This is called a REX BLOCK and is very, very stable.

The situation Tuesday afternoon still shows a ridge of high pressure/heights along our coast.

Better get use to temperatures in the mid to upper 60s.

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Final Call for the Northwest Weather Workshop on May 3-4

There is one local gathering each year in which regional meteorologists and interested layman get together to talk about our weather and its impacts:  the Northwest Weather Workshop.  This meeting is open to everyone.

The workshop this year will be on May 3-4 at the NOAA/NWS Sand Point facility in north Seattle.

The first day will include a session on Northwest wildfires--their prediction, the smoke, the associated meteorology and more.    That evening there will be banquet and a special speaker from Washington Department of Transportation, talking about dealing with the cold and snow in February.  Saturday will have sessions on OLYMPEX (a weather field experiment in the Olympics),  advancing weather modeling, the cold/snow of February, and much more.  Lunch Saturday is included in the modest registration fee.  There are special rates for students.  Information here.

Typically, about 120-150 folks attend the meeting, which is held in Bldg. 9 of the NOAA Sand Point facility just north of Magnusson Park.  Folks often want to know where you have to be a meteorologist to come.   My answer is that 70-80% of the talks should be perfectly accessible to lay people.

from Cliff Mass Weather and Climate Blog https://cliffmass.blogspot.com/2019/04/wetter-than-normal-april-to-be-followed.html