Good morning and Happy Easter to you from SCW!
A dramatic change in the weather pattern has occurred since we last spoke, and it now looks like we are in line for a colossal blizzard tomorrow. Expect two to four feet of snow, with 70 mph winds and coastal flooding. For future forecast updates, come find me on a beach in the Caribbean, since we are officially sick of winter and relocating our operation to the tropics. Announcements on a name change forthcoming.
…
April Fools! Hope you checked the calendar before panicking, but hey, if we made you book a flight to the tropics, you probably needed a vacation anyway J
With that said, there is still a chance of snow in the forecast for tomorrow. Since the last discussion on Thursday, a pacific shortwave that was previously modeled to slide south of us and out to sea has come north far enough to bring some light snow into the region to start off your workweek tomorrow. While I have my doubts that this will be the significant event that some models show, I do expect to at least see some flakes in the air and some accumulations tomorrow, with a couple of inches of snow possible in the favored spots. Let’s take a look at the setup.
Models and Trends
Here’s a look at the evolution of the storm on the GFS.
A dramatic change in the weather pattern has occurred since we last spoke, and it now looks like we are in line for a colossal blizzard tomorrow. Expect two to four feet of snow, with 70 mph winds and coastal flooding. For future forecast updates, come find me on a beach in the Caribbean, since we are officially sick of winter and relocating our operation to the tropics. Announcements on a name change forthcoming.
…
April Fools! Hope you checked the calendar before panicking, but hey, if we made you book a flight to the tropics, you probably needed a vacation anyway J
With that said, there is still a chance of snow in the forecast for tomorrow. Since the last discussion on Thursday, a pacific shortwave that was previously modeled to slide south of us and out to sea has come north far enough to bring some light snow into the region to start off your workweek tomorrow. While I have my doubts that this will be the significant event that some models show, I do expect to at least see some flakes in the air and some accumulations tomorrow, with a couple of inches of snow possible in the favored spots. Let’s take a look at the setup.
Models and Trends
Here’s a look at the evolution of the storm on the GFS.
Pretty simple setup. A pacific shortwave tracks almost due east, passing to our south but close enough to put us on the cold side of the precipitation shield and bring some light precipitation to the region. A few of the models have been more aggressive with the strength of the precipitation shield at various times, such as the 18z RGEM from yesterday below, but any trend that we’ve seen to push the system further north and strengthen it has been quickly reversed on the next model cycle. In general, the model consensus is overwhelmingly for a light event, although I caution you that outliers can and do verify (hence our bust on the last event) and we can’t ever discard them entirely.
As far as QPF goes, looking at a consensus of generally a tenth to a quarter of an inch of QPF in northern areas and a quarter to a half of an inch in southern areas. In mid-winter, I’d be calling for 1-3” of snow in the north and 3-5” in the south based off of those numbers, but there are a couple of caution flags here that are keeping me relatively bearish. First off, we’ve already seen what a weak system against a dry airmass results in; last system was a prime example of that where we were forecast to be on the northern edge of the precipitation shield and ended up getting almost nothing due to the column failing to saturate. While this is a very different setup and the impacts of blocking to the north should be much less, it’s still worth keeping in mind. Secondly, given that most of this snow should fall during the day and it is in fact mid April, we need to consider the temperature profile and sun angle. Models are not especially for with this system, with temps generally in the 30-32 range. While that is cold enough to support snow, I think we’ll be seeing a lot of “white rain” unless rates are strong enough to overcome melting from the ground and from the higher sun angle. Some of the more aggressive models are strong enough to bring some banding up onto the south coast, in which case we’d likely be able to produce accumulations at pretty close to a 10:1 ratio. Aside from that possibility, the snow rates look relatively light, especially in northern areas, and so I’m thinking that shaving an inch or so off totals to account for melting is probably a good move here.
Personally, my gut feeling says that this is a relatively minor event, but it’s hard to ignore the almost unanimous consensus on the models for some sort of snowfall tomorrow morning. As such, will take the lower end of the forecast ranges and go with 2-4” for the south coast, 1-3” in central areas, and a coating – 2” in northern areas. Should the more aggressive solutions verify, we’d probably be about an inch too low across the board, but my confidence in that happening is low compared to what I think the odds are that this ends up as a general non-event for most. We’ll see what happens!
Forecast and Timing
Here’s our snowmap for this event.
Personally, my gut feeling says that this is a relatively minor event, but it’s hard to ignore the almost unanimous consensus on the models for some sort of snowfall tomorrow morning. As such, will take the lower end of the forecast ranges and go with 2-4” for the south coast, 1-3” in central areas, and a coating – 2” in northern areas. Should the more aggressive solutions verify, we’d probably be about an inch too low across the board, but my confidence in that happening is low compared to what I think the odds are that this ends up as a general non-event for most. We’ll see what happens!
Forecast and Timing
Here’s our snowmap for this event.
Unfortunately, the timing for this event is not the greatest; with the heaviest window of snow coming right in the middle of the morning commute. Should see snow start to break out in the SW corner of the state by about 6 AM and continue to overspread the state over the next hour or two. The system will be quick, with snow wrapping up in western areas by 11 AM or so and in eastern areas an hour or two later, but any heavier snow bands that do develop will be enough to cause issues during the morning commute. Nothing impassable by any means, but definitely leave plenty of extra time tomorrow morning and consider delaying any unnecessary travel until the afternoon when conditions will rapidly improve.
Impacts
Here’s the SCW impact scale for this event. I would expect some school delays across the state; not sure if any districts will choose to close given the timing of the event but given how quickly some areas have jumped to close school this year it wouldn’t shock me for some lucky folks to pick up another snow day out of this storm.
Impacts
Here’s the SCW impact scale for this event. I would expect some school delays across the state; not sure if any districts will choose to close given the timing of the event but given how quickly some areas have jumped to close school this year it wouldn’t shock me for some lucky folks to pick up another snow day out of this storm.
Overall, a relatively minor event, but still enough to cause problems given the timing and the morning commute. We’ll update tomorrow morning on our social media platforms to give you a live look at the system, and we welcome your observations as well! Thanks for reading SCW and have a happy Easter with your family and friends.
-SA
-SA
