Northwest Mountain Snow in June: A Cold/Wet Period for the Northwest

The images from the Mount Rainier Lodge area during the last day were winterlike, with several inches of snow on the ground

The Crystal Mountain ski area was similarly snow-covered.

And Whister Peak appeared more like March than June 

Thunderstorms, with small hail, hit both sides of the Cascades, with substantial precipitation totals yesterday (Saturday); many mountain locations received over an inch of liquid water.

This situation has brought much colder than normal temperatures to the region, with many locations 10-20 F below climatology ( see below).   Many higher terrain locations did not get out of the 30s!

But even colder and wetter weather is in the forecast, with major positive implications for water resources this summer.

The forecast temperature anomaly (difference from normal) for the region for Tuesday to Wednesday morning (below) is for 5-15F below-normal temperatures, with the coldest temperatures over the Cascades and eastern Washington and Oregon.

Wet conditions will dominate from late Monday into Tuesday morning, with some locations in the Cascades receiving 1-3 inches.    Very favorable for water resources this time of the year: moistening the soil, filling reservoirs and rivers, and reducing water demand.

The origin of this cold/wet period is anomalous low pressure (roughing aloft in meteorological parlance), as shown by the upper-level  (500hPa, roughly 18,000 ft) forecast map for Monday at 5 PM.  Blue indicates the low/pressure/troughing

Temperatures should recover a bit by the end of the week (see forecast through Friday for Seattle, shown below), but we will have to endure a cool/wet period first.