Showers & rain returning in an on/off pattern.  Let’s take a look ahead.

On/off dampness today, with WIND really kicking-up during the day as a Low moves onshore in southern Vancouver Island later this afternoon.  WIND gust up to 40 mph possible inland, esp OR.  Saturday should be mixed, with some precip, at times.  Not super wet.  Cooler on Sunday, with additional showers across the PNW.  

Monday is looking DRY, other than some showers over far NW WA & Vancouver Island later in the day.  However, that wet system will spread south overnight Monday, ushering in a wet Tuesday.  Wed is trending damp, esp north of Portland - cool temperatures, as well, with snow level around 1,000-1,500 ft.  

It should dry out overnight Wednesday for a long stretch of DRY WX from Thu Feb 9 through the following weekend into Tue Feb 14.  A big Dome of High pressure (>1050 mb) will center over Yellowstone Nat’l Park by Fri Feb 10 (next week).  This will set up a brisk EAST wind out of the Columbia Gorge (to a far lesser extent out of the Fraser Gap) late the 10th.  East winds will flow over the Sierra Nevada Range, as well.  Again, this dominant High should hold off any PNW rain until Valentine’s Day, Tue.  California likely to get damp overnight Sat the 11 into Sunday.

Following Valentine’s Day, PNW weather may return to a mix pattern of wet/dry, or, another Yukon cold air outflow could develop from the north.  We’ll monitor this closely.

Quite cold this a.m., with a very dry air mass, so don’t be surprised if you catch a ’snap’ of static electricity!   Your morning bev will be snap-free.

The air mass will slowly warm, with good doses of sunshine, as the week progresses.  A weak system may clip Vancouver Island and the far north corner of WA Tue night with rain/snow showers.  By late Thu - Groundhog Day, the general wx pattern will shift back into a damp period.  Overnight Thu into early Fri, expect rain to return; it may get a bit WINDY, esp along the coast.  

For the PNW, Fri - Tue, Feb 3-7 we can expect rain and showers, a few sun breaks, decent snow in the mountains and temperatures on the cool side, esp late in the period.  The next DRY stretch of wx is charting for Wed Feb 8 through Valentine’s Day.  Mild temps, maybe even a chance at hitting 60 degrees in the Willamette Valley (if no fog) on Sunday Feb 12.

Looking out past Valentine’s Day we see an outside chance for another cold snap — just a ponder point for now.

Our closing quote today ties in well with the latest forecast, so get set, ready, read.

This past week of rather bland weather is coming to an end today, with showers moving across the region as this is written.  On Saturday, as discussed previously, a MUCH COLDER air mass arrives, driven in by High pressure dropping south out of the interior of Canada.  The front edge of the modified-Arctic air will not carry a lot of moisture, so showers and snow showers will be limited.  However, by late afternoon on Saturday, as the cold settles in via STRONG Fraser Gap winds, any moisture will fall as SNOW.  Said cold air will also push west out of the Columbia River Gorge late Saturday, so portions of western OR could also see showers of The White in the evening.   

By Sunday, the entire PNW will be QUITE COLD, with high temps struggling to exceed 35-39 degrees; potentially a bit COLDER ON MONDAY, Jan 30.  Overnight in the low 20s, in wind sheltered locations. Mittens time.  East winds will slowly diminish late Sunday; while it will be rather windy in southern OR, northern CA.  Models are split on whether or not moisture returns on Tue/Wed; if it does, it will fall as snow or snow/rain mixed.  Most of the precip is charting for north of Salem/Portland, and will turn to rain later on Wed, if it arrives at all.

That said, The next threat for precip is now trending to arrive late Thu or Fri; it could hold off until Fri night.  This system will move in from the west/southwest, so rain is the may form of precip we’ll receive.  The air mass west side should warm up enough to mitigate any snow threat, although that will be a possibility for the Gorge.  We can review this on Jan 30.

The first weekend of February is looking wet, with temperatures much warmer than the previous week.  Our ‘return to winter’ conditions will also mean a major cold snap for much of the Nation next week.

From the ’Net:  “It’s like winter is really mad and keeps storming out of the room and then coming back yelling, ‘And another thing!'"

Will another modified Arctic outbreak arrive as the month ends?  Go refill that Mug and get back here, will ya?

This week will be dry across the PNW, with fog at times, along with a few peeks at the sun.  It will remain on the chilly side, as colder air is trapped at the surface, with a ‘warmer blanket’ over the top.  Accordingly, stagnant air will become an issue as the week progresses.  Indications are for the Pacific High to shift a bit farther west by week’s end, opening the door for a colder, continental air mass to push in from the north.  Indeed - as we suspected 10 days ago - a Yukon Dome of High pressure exceeding 1040 mb is charted to move south along the Canadian Coastal Mountains & Canadian Cascades, setting up a renewed chance for a modified Arctic Event as January ends.  That said, expect the leading edge of that cold air mass to move into position by Friday.  A very weak Low may be pinched between ’the two highs’ we noted last time, so a shower or two is possible anywhere in the PNW as the week ends.  

By the weekend, a COLD Fraser Gap WIND should increase on Saturday the 28th; east winds out of the Columbia Gorge will ’turn on’ later in the weekend.  The air mass, which will have Arctic origins as a 1040-1042 mb High, will press south - centered over the Continental Divide - and should be large/heavy enough to push cold air across the eastern basins of the PNW, through the “gaps” into western valleys.  Early yet for forecast precise low temps, but it will be the coldest air mass since the Dec event; it may end up colder.

The final two days of January will start the week with cold air in place.  No wet system is charting to arrive just yet, so freezing FOG will be quite possible in the usual foggy-bottom locations.  

Models do vary quite a bit as to the start of February.  Some suggest that a cold, wet system will track SOUTH along the BC coast, bringing cold-core moisture in over the cold air at the surface - which would fall as snow or ice pellets.  This would be on Wed Feb 1, or that night; with just plain SNOW on Ground Hog Day.  Other solutions bring moderate precip in from the WEST, which would trigger a freezing rain event during the week.  Either way, Patrons should be prepared for another winter event that could hinder travel/outdoor plans.  

Bear in mind that, while the above scenario is probable, the timing of arrival for the colder air can have a 12-24 hr swing.  That is normal when these events threaten.  Or, it can simply not happen at all.  We have seen this on the charts for several model runs, so this forecast is warranted.

Hard to believe it’s already Friday and we are 20 days into the New Year.  Let’s take a look at the dry weather ahead.  Hot java ready.

Foggy bottoms in many locations this morning, as can be expected after a wet spell followed by cool temps and no-to-low wind.  This will be the pattern for the next couple of weeks, with the exception of a chance for showers, mainly Salem north to BC sometime tomorrow.  Overall, though, the weekend should balance out as mostly dry, COOL.  The PNW is caught between a High pressure ridge to the west and another to the east, which will keep any significant rain from coming into play until at least the last couple days of January.  This pattern favors periods of air stagnation.  California continue to dry out, with a NE wind, at times.  

While the majority of model solutions for the end of January keep the PNW in an extended dry pattern, there have been a few scenarios of a cold air shot from the north, with minor Fraser & Columbia Gap outflows on the last 2 days of the month.  Broadly, we will call for the next threat of rainfall to arrive during the week of Jan 30 - Feb 3; some solutions say rain by the 1st, others by the end of the week.  We’ll see.  

Early Feb is trending WET for the entire PNW and CA (north of Pt. Conception).