A Quick Saturday "Tease"

A Quick Saturday “Tease”

A quick Saturday afternoon update since my house is full of 25 women enjoying a family baby shower! Help me! 🙂 By now, most of you have seen the latest models or heard from other sources that the Pacific Northwest could be in for a BIG late season arctic blast with the increased chance for accumulating valley snow this coming week! Well, as of this morning the “BIG 3” model consensus is only the “BIG 2” at the moment. One model is wanting to tease us and then do the same thing it did this weekend, which is to dig the cold trough off the coast and send the cold air around us, rather than through us. So, what’s the end result going to be? I plan a full update here no later than 12 noon Sunday. We will be within the 72 hour window by then. But as it sits now, I am not ready to pull out all the stops. Ironically, the one model that is putting the brakes on an “all out arctic assault” is the very same model that nailed this weekends “no snow” forecast before the other models did. That is something to watch closely. If it is going to get back on board, it should happen by tomorrow (Sunday). If it doesn’t join the others, as was the case this weekend, the chances for a big blast could be considerably less. In my 15 years of analyzing weather models online, I have rarely seen an instance where a big arctic blast wasn’t well forecasted by the “BIG 3” at least 72 hours out.

So, enjoy the sunshine today and check back for a full / detailed update no later than 12 noon Sunday.

Stay tuned!
Steve

Thursday Afternoon Update

Good morning! A quick Thursday afternoon weather update concerning what I see coming over the next few days. There are some changes this morning that will have an impact on the majority of the Portland / Vancouver metro area, especially with this being a holiday weekend for many of us. Got travel plans this weekend? If they include traveling over the Coast Range or the Cascades, better prepare for winter driving conditions, especially at night.

So, what about the Friday and Sunday systems I referred to yesterday? As previously mentioned, the Friday system appears to be on track for sliding down the coast Friday morning. Latest guidance is now in pretty solid agreement that the main focus of the precipitation will be from the coast range west to the coast. That means many of us in the valley and metro area will likely escape any snow tomorrow morning. Perhaps a little on the west side of the metro area. But what about the coast itself? For those of you down there, you may see one of those rare events like in 2008 where the low tosses up plenty of precipitation right along the coastal strip. This will also be the focus of the coldest air as it all slides south in the morning. In fact, I would not be surprised if some locations between Lincoln City and Astoria get a rare (but not completely uncommon) snow day tomorrow morning. Maybe a few inches possible? Looks like the snow will stay just off the beaches itself. But it will be close. It is simply to close to call. For transportation and emergency management folks, I expect the focus of the snow tomorrow morning to be in the coast range from Lincoln City northward to Astoria. Keep and eye on the radar loop in the morning. The system should clear out of the area by the afternoon and evening.

What about Sunday’s advertised potential for an area-wide snow event? As of this morning it looks like we may just dodge a bullet with that one as well. Models have come into better agreement that a cold trough from the Gulf of Alaska will slide down the coast Sunday, taking a similar path to the system on tap for Friday. The difference in the Sunday system is that it will be a little further offshore than the first system on Friday. Thus, less moisture across the area. In fact, most models show very little moisture now across the area on Sunday.

But wait! There is more! Just when we thought that we could not be “teased” any more than we have been all winter, two of what I refer to as the “BIG 3” computer models are suggesting that we could see an all out arctic blast next week. Now that is a long ways out and I put little faith in a forecast like for now. However, the pattern is ripe for something like this and it will need to be watched over the coming days! If that guidance were to verify, it would be the coldest late February air mass in decades across the area. But let’s not get to excited yet! There is plenty of time for the models to flip flop. Speaking of which, I need some additional asprin. My head hurts this winter!

Synopsis

Friday – Valley to remain mostly dry. Temps well above freezing. Coast range and perhaps even the coastal communities from Lincoln City north to Astoria are likely to see “some” snow in the morning before letting up in the afternoon.

Saturday – Dry and mild in the metro area and the coast

Sunday – Mostly dry in the metro area with just a change of light rain along the coast.

President’s Day – Mostly dry and cool. 70% chance of a vacation day (for some of us)!

Extended outlook for next week – Watching the potential for a MUCH colder air mass Tuesday – Thursday.

Enjoy the holiday weekend! If anything exciting and unexpected develops over the next few days, it will be posted here as soon as possible!

Stay tuned!
Steve

Photo Courtesy: Jeff Pierce, Vancouver (McLoughlin Heights – 300ft Elevation)

Good morning everyone:

Wasn’t that fun? Many areas across the Portland / Vancouver metro area received accumulating snow this morning as a cold upper level trough parked off the coast rotated bands of moisture inland. Areas that received the most snow were located west of I-5 in Portland and north of the Columbia River in Vancouver / Clark County. Areas south of the metro area and east of I-5 in Portland did not receive much if any snow. This was mainly a “westside” and “Clark County” event. At one point snow flakes were reported to be as large as half dollars across Beaverton, Hillsboro and Vancouver.” As of 10:30am, here are a few snow totals reported through local observers —

Sunset High School – 0.50″
Hillsboro / Tanasbourne – 0.25″
Vernonia – 1″
Vancouver, McLoughlin Heights – 1.50″
Tigard (base of Bull Mountain) – Trace
Battle Ground – 2.5″
Felida – 1″
Hazel Dell – 0.75″
Ridgefield – 2″

“As of 10:30am, snow showers are coming to an end and moving north of the metro area. Temperatures are continuing to warm and will stay above freezing for the remainder of the day. The evening commute should be relatively unaffected. Bands of snow and rain showers will continue to rotate across the area today. Light accumulations are possible in the lowest elevations with perhaps 1-2″ possible above 1,000ft. The National Weather Service has an advisory issued for the area that covers this well. Longer range models show this pattern is going to stick around for the rest of this week and into the weekend. Additional disturbances are forecast to rotate down over the Pacific Northwest from the Gulf of Alaska at varying intervals over the next five days. With each one of these systems will come a renewed threat of snow down to the lowest elevations. As of this morning, model guidance suggests that the next organized system will arrive early Friday morning. This system may stay far enough off shore to have no direct impact on the metro area. A more organized and colder system is forecast to arrive on Sunday. Although it is to difficult to pinpoint the finer details at current lead times, this system has the potential to bring a more ubiquitous snowfall to the entire metro area. This system will be watched closely in the coming days. Snowfall levels will remain between the surface and 2,000ft for the next several days. Anyone traveling over the Cascades or the Coast Range should be prepared for winter driving conditions.”

“How rare is February snow in the metro area? It has been a number of years since the metro area experienced a substantial snowfall event in the month February. The last notable events occurred on February 12th 1995 and February 19th 1993 where between 6″ and 12″ fell across the metro area. The 1993 event holds the record (at the Portland International Airport 1940-2011) as the most snowfall in a single calendar day, in the month of February. Just over 6″ of snow fell.”

By the way, if you have snow totals to report, please do so here! Include total, location and elevation.

Stay tuned!
Steve!