Weather patterns for the PacificNW

[jssailem]

This is the start of Christmas Week. Kids off school. Holiday gift buying. So what will be the weather conditions.

JamesG has been kidding me about the influence of the ENSO current changes on our NW weather pattern. While it has been a mild start to winter here, moderate temps and periods of rain (routine for the PacificNW), JamesG repeats... "You are going to get cold wet snowy weather. Better button up.."

Rufus has posted his forecast for the end of December. It looks like after Christmas JamesG may get his forecast come true... Dammit Jim!

Here is the latest word from Rufus.

Monday December 18

Fairly dry week ahead before plenty of rain arrives. Mug up time.

A moderately weak Low pressure cell west of the northern CA coast will slowly work its way north, off both the OR & WA coasts today & Tue. The result will be increasing chance for showers for the west side up into BC, mild temps and clearing, from the south, later on Tue the 19th. Dry conditions return Wed & Thu. Fog, too.

Late Thu night Dec 21 a system will move in from the NW. This one will be supported by cold air aloft, so snowfall can be expected in the mountains (finally) and maybe a dusting in the coast range. Other than a few showers Fri afternoon, the main impact will be chilly temperatures, with snow east of the Cascades. Christmas Eve continues to trend DRY and chilly, with a brisk east wind. A good day to put on that Christmas scarf.

Christmas Day 2023: The heavy-hitting storm pattern mentioned in our last report is being delayed a few days by the models. Meaning, the early hours of Christmas will be dry, with increasing clouds and rain as the day unwraps. The much-weaker-than-expected system, will move in from the west, so it is possible for freezing rain or snowflakes to fall in the eastern portions of the Columbia River Gorge Christmas night into Tue Dec 26. Breezy west side. The heavier rainfall will be centered on northern CA Tue. The PNW will miss the early portion of the heavy rain, as the first half of this stormy period focuses on CA.

Wed Dec 27 should present a very stormy night, with a Low center pressured storm at 978-982 mb moving northeast up along the coast of OR & WA. Weather models have struggled with locations, depths, and timing of a series of strong storm centers developing along the battle zone of warm & cold air masses over the Pacific. Let’s just say that there will be a stormy period during the week following Christmas, with WIND, rain, Cascade snow and chilly temperatures after each storm front. This pattern is likely to remain in play through the last weekend of 2023 and early 2024. More on this in our next report, Fri Dec 22.

Interesting that December may end up with a 'wet close', just like November.

“A recent retiree writes that he’s tired of retirement already, “I wake up in the morning with nothing to do, and by bedtime I have it only half done."

-Rufus

 

[Kings Gambit]

Thanks John! Doesn’t look bad next week for us here in Southern California. I’m staring to look for the New Year’s Day weather forecast. Admiral and I go day sailing on New Year’s Day to start the new year off “right.” New Year’s Day 2023 was very windy and blustery in Long Beach Harbor with gusts forecast to 30+ kt. Our invited passengers bailed that morning just as we were getting the boat ready to receive. We went anyway, but not out into the harbor. (The same harbor where Howard Hughes flew the Spruce Goose on its first and only flight.) We stayed inside Alamitos Bay for a couple of loops around under the 120% headsail. It was fun. Went to late lunch afterward at a new beachside restaurant in Seal Beach. So nice. Here’s wishing you and our friends here at SBO Merry Christmas and the Happiest of new years! Get a good start on 2024.

KG

 

[JamesG161]

It looks like after Christmas JamesG may get his forecast come true... Dammit Jim!

 

[shemandr]

We used to have a New Years Day sail in Cutchogue Harbor near New Suffolk on LI's North Fork. It was the best! Years ago we would have to break through skim ice to get out. Some even launched their trailerable boats at the ramp there. I had my Mark 25 relaunched after winter layup but it was worth it to start the year with a sail.
Eventually the boatyard and insurance companies made it impossible. A great loss!

 

[jssailem]

WINTER IS COMING
I know I’m in the Caribbean. I checked out the PAC NW Weather Sunday, then Rufus sent me the long range forecast, and Port of Everett announced potential closing. It looks like checking on your boat lines are in order.

We are experiencing rain showers driven by North Atlantic Storms today. It’s not all blue sky’s and bikinis.

Stay safe.

Monday January 8

Lots of weather action on the way for the next several days. And, there remains plenty of variance in model projections as to whether or not snow reaches the surface or remains above 500-1,000 ft later this week. Let’s take a look. Mug time.

Rain has begun. Today (Monday) will be damp, with increasing WIND & RAIN intensity overnight into Tue. A large, deep Low is moving onshore north of Vancouver Island, but it is so deep (visualize a large bowl with the center north of Vancouver Is.) that the WIND FIELD from the storm will impact western OR & WA. Gusts are likely to exceed 50 mph, esp around the Puget Sound region (& coast, of course). Simultaneously, freezing levels will drop fast, ushering in a MAJOR BLIZZARD situation across the WA & OR Cascades. Nat’l Wx Service personnel have posted several warnings about this situation. Stay out of the mountains for a few days. Snow will be measured by the feet; wind gusts to exceed 60 mph. Visibility - don’t even think about it. Coastal flooding is a concern, as king tides will be ‘magnified’ by the strong onshore winds.

Tue & Wed Jan 9,10: a secondary smaller system is modeled to come onshore somewhere around Astoria late Tue evening. Areas north of that Low may get snowfall down to the surface, or very near so. (We should note that this smaller Low may not even develop.) Expect less rain on Wed, with colder temps and the chance for rain or snow showers around the entire region. Similar for Thu, except that Arctic air will begin to rush through the Fraser Gap - dropping temps even more across northern WA and BC. Snow showers possible all day into Fri during this Gap outflow. Western OR & SW WA should see rain/snow showers, but the air mass may remain warm enough at the surface to limit any snowfall.

As the modified Arctic air mass settles farther south & east, the eastern basins of WA & OR, as well as ID, will continue to chill down. The bulk of the super cold air will remain east of the Rockies (per the latest model solutions). A warm front will move onshore Fri night or early Sat morning - this will set off the chance for snow, freezing rain, or rain, depending on 1) how much cold air fills into the eastern Columbian basin and central OR to flow out of the Columbia Gorge or down the Cascade passes in WA; 2) southern surface winds. Right now, the greatest threat for frozen precip looks to be over NW WA and maybe Portland area. The precise center of that Fri night Low will be key. Stay tuned to local forecasts, as this situation will not be static, with small positional changes having a big impact.

The weekend of Jan 13,14 looks mixed. Snow, freezing rain or rain. The Low mentioned above may become stationary west of Astoria and fill in without crossing the state. Cold air to the east will be drawn west, so hence the mix of frozen precip depending on your location. The Fraser Gap winds will lessen, but remain present, adding cold air to the ‘pool’ in place from earlier. Remember though, the coldest portion of this event may remain east of the Rockies, and not be so severe as to keep the west side in a snow plane. Snow in the Tri-Cities & the rest of the Cascades.

The air mass should warm slowly over the weekend into the early part of the Jan 15-19 period. Another strong storm system is charting to develop and move south along the BC coast on Tue Jan 16, but this time it is charted to “bump into” a warmer air mass moving in from the west/southwest. Result: moderate-to-heavy surface rain - first over western WA, then shifting south into OR by Wed. WINDY. We do not see a repeat of a cold Yukon air mass pushing through the Fraser Gap, as the Low will track north of the border.

Heavy rain may develop by Fri Jan 19 and last until early Sat Jan 20. Oregon to get the brunt of this deluge. It could be mostly dry Sunday and Mon, Jan 21,22, then turn wet again for western WA for a couple of days; OR may dry down. Temps will be mild during this period.

Again, lots of uncertainty. Best to be prepared for winter conditions. As we said the other day, getting in & out of the PNW by road will be a “whitemare” - blowing snow everywhere higher than 1,000 feet.

“It seems that heads, hearts, and hands would settle the world’s differences much better than arms."

-Rufus

 

[JamesG161]

a MAJOR BLIZZARD situation across the WA & OR Cascades

I love that Science works about Snow and the Troposphere removal of Heat.
In addition to when it melts, more Heat removal.

dammit Jim...

 

[shemandr]

At least I now know where the Fraser River is...

 

[jssailem]

The Fraser River, south of Vancouver BC brings glacial silt out of the mountains to the valley and into the Georgia Strait.

The gap in the mountain range provides a path for the Arctic Yukon cold air to spill down on our sailing waters.

Brings snow conditions to friends on Saturna Island and the San Juan’s. It doesn’t even spare the folks in Maple Bay near Salt Springs.

It is a time to throw several logs on the fire and settle in with a Bailey’s & Coffee.

 

[jssailem]

Here is your Saturday morning update. By now you are like seeing the white stuff.
I heard from my wife the snow is falling in Salem OR at 400ft above sea level.

[wxcafe] Ice Box Open

Friday January 12

Yep, the freezer has been opened and Arctic air mass is filling in the PNW quickly. Plenty of coverage of the current winter event, so we’ll cover a few points that you may already know, and then look forward to the next couple of weeks, per usual. Hot beverage mornings on the way, for sure.

To quote Professor Cliff Mass, "This Arctic Front hit like a freight train.” Yesterday, the Arctic Front pushed down the Fraser River Gap and began “filling” the Puget Sound region with coldness. Winds gusted over 50 mph, Bellingham temperature dropped from 40F in the morning to 14F by 9 pm, per Cliff’s report. That Arctic air mass is rapidly filling in east of the Cascades, and should be pushing Arctic air down the Columbia Gorge Gap later this afternoon. Spokane is -4F this morning; Kennewick 16F.

Today is likely to be the last day above freezing for much of the entire PNW until Wed next week. The key issue for this weekend will be SNOW and/or FREEZING RAIN. Sleet will also be in play. Models have charted the wet Low moving in from the west to come onshore somewhere between Florence & Newport Saturday evening. The farther south it tracks, the less precipitation will fall north (Portland, etc), although that area would get snow. For areas south of Salem - freezing rain, sleet and maybe some snow is possible, depending on where a mid-level “finger” of warm air gets into position (that “finger” melts the snowflakes before hitting the surface as sleet or freezing rain). Either way, roads and sidewalks are wet, which means ICE as sunset hits tonight with the cold air arriving. KEEP THAT IN MIND. Best to hit the stores today for supplies and food. Moving about outside anywhere from Cottage Grove north will be quite slick. Patrons in the northern portions of the PNW may miss out on precip, but not the bitter cold. This event will likely be one of the colder Arctic outbreaks we experience in the PNW.

Temperatures: lots of variation, depending on snow cover and / or winds. Overall, nothing above 32F is forecast from later tonight through Wed, as mentioned. Portions of southern OR should remain above freezing. Highs will be in the 20s early on, with single digits or low teens possible overnight. Negative temps across much of the Cascades and eastern basins.

DRY pattern, which is typical for Arctic Outbreaks around the PNW, will hold for 3-4 days. Temps will moderate mid-week, as a weak, warmer system clips the PNW on Wed; a stronger system is charted for NW WA area Thu. Later next week, freezing rain or just plain cold rain for a bit looks more likely than snow, as the air aloft will be relatively warmer than the surface. Friday Jan 19 currently trends dry, and warmer, with an offshore flow that should minimize any fog issues.

Weekend of Jan 20,21: wet for most of western WA; NW OR could get a shower or two, but the system will track over WA this time around. Rain will return to OR on Mon the 22nd, and continue for WA & BC. Drying out late Tue for a stretch of dry days that could last into the following weekend. Some solutions indicate rain again on Fri Jan 26. Fairly mild temps for January.

Back to our current event: whatever form of precip your specific location receives over the next couple of days, know that it will not thaw out. Frozen water on roads will make travel challenging; walking, too. Ice will have to evaporate away, rather than melt. Be sure unfrozen water is available for any animals outside the next several days, etc etc. Wind chills (esp in the Gap outflow areas) will be dangerously cold, be sure to cover your skin.

“When you argue with a fool, two fools are arguing."

-Rufus