In this weblog I speak so much concerning the Puget Sound convergence zone, during which air strikes across the Olympic Mountains and converges over Puget Sound, producing a band of clouds and precipitation someplace between Everett and Seattle (see determine from my NW climate guide)
But generally, when the wind approaches the coast from a extra southwesterly path, the convergence line can shift northward, producing a line of precipitation from roughly Port Townsend to Bellingham. This is strictly the scenario that occurred this morning.
The radar picture at 6:46 AM this morning exhibits the story, with average (inexperienced) to heavy (yellow) rain in a band stretching to the northeast. Was actually raining laborious in elements of Bellingham and within the hills to the northeast of city!
The seen satellite tv for pc imagery about an hour later is fairly dramatic–you can see the cloud band stretching from the Olympics northeastward and profound rainshadowing north and south, with basically clear skies within the lee of the mountains of Vancouver Island and from north Seattle southward.
I’m proud to report that the UW WRF mannequin predicted this precipitation band within the run began 5 PM on Wednesday…test it out under (three hour precipitation whole ending 5 AM at this time)
The precipitation totals from midnight to midday at this time exhibits the outcomes of the convergence band with a few of the hills northeast of Bellingham getting over and inch.
In reality, Heather Meadows at Mt. Baker loved a torrent of 1.94 inches!
To get such a precipitation band, the low-level, larger-scale move approaching the Olympics from off the ocean wanted to be from the southwest, one thing confirmed by the winds round 5000 ft (850 hPa strain) forecast by the WRF mannequin at 5 AM.
Finally, I ought to word that with latest rains, the April whole is not going to find yourself anyplace close to report dry territory. The first half of the month was bone dry, however latest rains have introduced us comfortablly shut (however nonetheless under) to regular (see Seattle’s cumulative April rainfall under, cyan is regular, purple is that this 12 months):
More rain is coming, significantly on Saturday. Sunday seems respectable.