As shown by the latest (Saturday AM) infrared satellite image (see below, with my annotations), an upper low center is found over eastern Oregon, with substantial moisture rotating around it into our region. There is a substantial EASTERLY (form the east) component of the winds and that produces upslope precipitation on the normally dry easterly slopes of the Cascades. Eastern WA is also getting rain.
How much so far? Here is the 24h totals ending 9 AM Saturday over central Washington. Impressive amounts (over an inch in some locations) over the eastern slopes, will many locations wetted by more the .5 inches. Good rain over northeast Washington.
A band of precipitation is now circling into western Washington (see radar). My garden will be happy.
Normally dry, eastern Oregon has done very well from this event, with some eastern Cascade locations getting over 1.5 inches.
The latest WRF model forecast for the next 24 h (ending 5 AM Sunday), brings lots of rain to the central and southern Cascades, with relatively dry conditions along the coast.
There are a lot of folks worried about heat and drought this summer and potential impacts such as wildfires and poor harvests. This event is very positive as has been the reconfiguration of the atmospheric circulation. Eastern WA soil moistures are near normal and our reservoirs, such as those in the critical Yakima drainage are full and above normal (see below for yesterday...and that is before the today's rain).
However, with warm water still offshore, El Nino still be present, and other factors, the subseasonal forecast models are projecting warmer than normal conditions over our region this summer (see below). Not crazy warm like last year, but .5-1 C warmer. Warm temperatures encourage evaporation and thus contribute to surface drying.
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