A Look Into The Storm

The much talked about potential for lowland snow is finally here and we are in the range where we can talk about specifics. Tonight, a cold front is crossing the area, evident in satellite imagery.  Behind this cold front is much colder air which will filter into the area tonight. Temps are sitting in the upper 40's currently in much of the Puget Sound, by about 2 AM, much of the area will be in the 30's and a gradual cool down will continue. At this time there are several chances for lowland snow, but accumulations will be spotty as the system is more showery in nature and not organized.  There will be several areas with a heightened potential for lowland snow and I will point it out on this little graphic.  Zone 1 is in Snohomish county and has a heightened potential for snow due to the convergence zone setting up over there tonight and into tomorrow. There is a chance this extends southwards briefly so some of northern King county could also see some snow. I expect abo...

The models are beginning to compromise with each other and a clearer picture is emerging. It is becoming increasingly likely that many lowland locations will see snow this weekend into next week. Significant uncertainty remains as to who sees snow, when, and how much of it. The overall forecast is going to be challenging and a lot of the details will likely not be ironed until the event is actually underway but I will do my best to provide the most likely scenarios.  It all starts tonight, when a system moves through the area. This will bring the first real rainfall to the area in a while. At this point, the real cold, Arctic air is still hung up in Canada. On Friday evening, this cold air begins to move into Western Washington. Temperatures will drop significantly in a matter of hours. And as the winds from the north begin to collide with the southwesterly winds, a convergence zone will form.  On Saturday morning, most of Western Washington will be close to the freezing mark ...

Models have pulled back significantly since my last post. Initially, it looked like it would be a perfect setup for cold and snow with the trough digging south and a bit over the ocean which helped with snow chances. Now models are starting to show most of the cold eject out into the Pacific which would not be favorable for lowland snow. The change is clear in the 18z GFS, the trough doesn't dig into the Northwest and instead goes out over the ocean. Similar with the EURO. Although SOME over the ocean trajectory can be good for lowland snow, this is way too much over the water and it doesn't really get the cold air there. This is well illustrated on the 850 MB temp maps which were showing temps get down to -10 but now only down to -7. This is because the trough doesn't really dig south and most of the cold air never makes it to Washington or Oregon. -7 is still cold enough for snow and I will get into snow chances next. But this is certainly a major step back from what the ...

 It's been pretty cold of late in the Pac West so far, however, nothing in terms of snow for the lowlands. According to the models, that might change soon!! I'm almost scared to mention the possibility of lowland snow with how the last couple of winters have gone so far, especially for those of us in the Seattle area. But, the possibility is now only a week out, giving me a bit more confidence.  In terms of weather around the country, nothing much but I did hear about something in New Orleans. Probably not a big deal, so we'll move on. Seattle and Portland have been running negative departure so far this month, and will likely finish with it. Then, next Saturday, as the calendar turns to Feb, things get interesting! Upper Air Pattern So far this winter, we've been stuck in a fairly progressive pattern. But that changed about a week ago. A block has set up in the GOA, which prevents any systems from the Pacific, riding the jet, from affecting us. Meaning, most systems wo...

 The coldest weather of the winter is coming to the Northwest, which isn't saying much considering how this winter has gone so far.  Most of Western Washington has been stuck in fog today and will continue to be, keeping temperatures confined to the 30's. A weak disturbance will cross the area tomorrow bringing some showers to the area but it shouldn't amount to much.  Temperatures will be similar to today. I want to note that any residual moisture on Friday morning would fall as a mix of rain and snow or as snow showers, but most models clear out all the moisture by then. Moving on to the weekend, we will get clipped by a very cold air-mass moving into the middle of the country. Temperatures will plummet, especially in Eastern Washington as a cold air pool will begin to build. In Western Washington, highs will be in the upper 30's to low 40's with lows in the mid to upper 20's. There is no moisture present during this time, and clouds should clear out making fo...

 It's been a benign winter so far in the PNW in terms of cold and snow. Part of Texas, Georgia, Alabama and other southern states have recorded colder temperatures and more snow than us!! But, there is some light at the end of the tunnel as a period of cooler weather is likely next week.      We finally broke the streak of rainy days last week and places that weren't entrenched in the fog, had a string of nice, sunny days! This will continue into the upcoming week after a light disturbance on Sunday which should bring a bit of drizzle, but nothing impactful. Highs will remain in the lower to mid 40's and lows in the 30's. Some favored areas could score a couple of freezes this week, before a more widespread chill next week.            Pattern Change     On Friday, a batch of frigid, arctic air from the north will slide into the U.S, most of the frigid air will well east of us, but there will be more than enough cold air for a d...

It's been constant rain this winter as we stay stuck in a stubborn pattern with the Pacific jet, battering us with storm after storm. I can't even remember the last day it didn't rain, and was shocked to see that the last day the airport did not see measurable rain was the 11th of December!!! That is one incredible stretch of dark, miserable weather! Thankfully, we will have a bit of a break from this starting Monday. As a ridge settles over us, expect plenty of chilly mornings with fog, but as the day goes on, you may even notice an interesting feature in the sky, called the sun. 🌞  Not much else to discuss in terms of the weather here in the NW, it hasn't snowed so far this winter in the western lowlands, and we aren't expecting to see any snow or significant cold in the next couple of weeks.     Back in the east, an active winter continues, with another arctic blast and a major snowstorm in the Midwest. Up to 18 inches of snow could fall in parts of Kansas, Miss...