Models agree that a major storm will form a few hundred miles off the coast on Tuesday and Wednesday.
The storm is called a “meteorological bomb” because its central pressure will increase by more than 24 hPa in 24 hours.
Here’s the forecast from the UW model for Wednesday 10 p.m.: the deep low of 964 hPa is gigantic in size. Strong pressure gradients and therefore strong winds over a large swath of the Pacific Ocean.
A simulated satellite image close to the same time shows an extremely large storm, with associated fronts located more than 2,000 km away.
Strong winds will swirl around the storm for hundreds of miles as shown by Thursday’s 4 p.m. sustained winds predicted by the Central European Model (solid lines are pressure, color are sustained winds, with red/brown being strongest–red 40 knots). A dangerous time to sail offshore.
While still offshore, this storm will have significant impacts along the West Coast.
With such a big storm over the Pacific Ocean, with its large scale and strong winds, it will create large waves. For example, the NOAA WaveWatch3 model predicts that 20-30 foot waves/waves will reach the Northwest coast on Thursday morning (see below).
I suspect there will be some good wave-watching on the coast (but be careful if you do that).
And to the southeast of the major storm there will be a plume of moisture into California (see low-level wind vapor transport forecast for Wednesday morning, blue at most).
As this humidity is forced to increase due to California’s solid topography, heavy rainfall will occur (see cumulative precipitation forecast through Wednesday below). Great for helping alleviate the “drought” in California.
And finally, with strong low pressure offshore and higher pressure east of Washington, a large pressure differential will develop on the Cascadesresulting in strong winds in the foothills west of the Cascades, particularly in locations like North Bend and Enumclaw (see Wednesday night gusts forecast below–dark blue and stronger green.) SeaTac Airport will be affected by this.
For a meteorologist, a big storm is a fun way to start the new year. And the latest long-term modeling suggests more powerful storms over the next 10 days. 😀 One can have our name on it…
