Portlanders will tell their grandchildren about this.
Heavy snowstorm in Portland in April.
The latest NOAA/HRRR forecasts show heavy snowfall over the lowlands of SW Washington and NW Oregon for the 24 hours ending 5 p.m. Monday, with several inches around Portland. A drive down I-5 tomorrow morning could be exciting. Driving through the Canyon can be dangerous. And the southern Cascades will be hit hard.
The higher resolution UW prediction model also has a similar solution (see below)
This snow is very welcome, as Oregon snow and ice are currently below normal. An end-of-season snow blast has a major impact on the fire season.
Why this unusually prolonged snow/cold event?
We start with a very deep bottom above (see Monday 5am forecast below at 500 hPa … about 18,000 ft). Very impressive.
And this trench creates a deep low center (see surface forecast at the same time), sucking cold air in from the north. In addition, heavy rainfall from this system will cause the atmosphere to cool by evaporation and by melting snow from above.
