Good evening from Southern Connecticut Weather.
Well, there's no time to take much of a breath after the blizzard that ended yesterday, as the fast flow pattern that has been a hallmark of our winter amps up once again. In the last week we've had three events, and three more possibilities are on the table in the coming seven days. This discussion will take a look at each, with most of the focus put on the event that's coming in less than 12 hours. It's pretty late for a discussion, but that's the product of the fast flow. Let's dive in.
Well, there's no time to take much of a breath after the blizzard that ended yesterday, as the fast flow pattern that has been a hallmark of our winter amps up once again. In the last week we've had three events, and three more possibilities are on the table in the coming seven days. This discussion will take a look at each, with most of the focus put on the event that's coming in less than 12 hours. It's pretty late for a discussion, but that's the product of the fast flow. Let's dive in.
Above: the snow map for tomorrow's event. I'm going with a general 1-3" through the entire day.
General Setup
This one is pretty easy in terms of identifying the setup. A clipper is coming! What had practically been on the endangered species list the last few winters has made quite a comeback. Simply put, tomorrow a clipper will quickly dive down from Canada and zip through the region. It'll be in and out in just a few hours.
The GFS below captures it nicely. If you blink you'll miss it.
General Setup
This one is pretty easy in terms of identifying the setup. A clipper is coming! What had practically been on the endangered species list the last few winters has made quite a comeback. Simply put, tomorrow a clipper will quickly dive down from Canada and zip through the region. It'll be in and out in just a few hours.
The GFS below captures it nicely. If you blink you'll miss it.
The Forecast
Timing
If you recall from a week or two ago, I mentioned how the Arctic presses that had been another core feature of the winter were effectively done, but that had the impact of making this period the most favorable yet for snow chances. This is because we will be right in the battleground between colder air to our north and warmer air to the south. This only gets enhanced as spring tries to overpower winter in late February/early March.
If this clipper was arriving even three hours later, I'm not writing about it here. However, it's coming in the morning as temperatures are just starting to rise out of their morning lows, which means snow is mostly on the table.
Currently temperatures around the state are well below freezing, and as the clipper arrives in the morning we will see our temperatures shoot up. It'll be a race between the precipitation arriving and temperatures getting above freezing.
Snow breaks out between 5-8am from west to east. The snow lasts until between 11am and noon. Because this is an early morning event for the most part, most of the state should remain snow, even as the temperature tries to beat the arrival of the precipitation. This gets tricky in SE CT, where some models actually enhance the snowfall a little while the system is racing through while others have the temperatures winning out and flipping the area to rain before that happens. I think the snow will win out.
By the afternoon, most of us are above freezing and the snow is melting everywhere. That said, we will have a low but nonzero chance of snow squalls later in the day. That's something that will be a nowcast.
Here is a side by side comparison on the high resolution NAM, showing the precipitation between approximately 4am and noon and temperatures during the same time period.
Timing
If you recall from a week or two ago, I mentioned how the Arctic presses that had been another core feature of the winter were effectively done, but that had the impact of making this period the most favorable yet for snow chances. This is because we will be right in the battleground between colder air to our north and warmer air to the south. This only gets enhanced as spring tries to overpower winter in late February/early March.
If this clipper was arriving even three hours later, I'm not writing about it here. However, it's coming in the morning as temperatures are just starting to rise out of their morning lows, which means snow is mostly on the table.
Currently temperatures around the state are well below freezing, and as the clipper arrives in the morning we will see our temperatures shoot up. It'll be a race between the precipitation arriving and temperatures getting above freezing.
Snow breaks out between 5-8am from west to east. The snow lasts until between 11am and noon. Because this is an early morning event for the most part, most of the state should remain snow, even as the temperature tries to beat the arrival of the precipitation. This gets tricky in SE CT, where some models actually enhance the snowfall a little while the system is racing through while others have the temperatures winning out and flipping the area to rain before that happens. I think the snow will win out.
By the afternoon, most of us are above freezing and the snow is melting everywhere. That said, we will have a low but nonzero chance of snow squalls later in the day. That's something that will be a nowcast.
Here is a side by side comparison on the high resolution NAM, showing the precipitation between approximately 4am and noon and temperatures during the same time period.
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Snowfall accumulation and overall impact
This would normally be a minor event at best, but the timing is the worst it could possibly be. Not only will we have black ice given the melting today and refreezing that is happening tonight, the snow is coming in right during the AM commute. As a result, we will likely see widespread delays and some cancellations tomorrow morning. Because the snow is likely to last into the late morning that may make it tough for some school districts to make a call on delay vs cancellation, though I am guessing that losing two days already will make folks want to get the school day in badly.
By the afternoon we're fine, but the timing is rough. Expect a limited but moderate impact on the roads tomorrow.
As for the snowfall totals, again, we're expecting a general 1-3". Given the race between the precipitation and temperatures, I expect the most snow to fall in northern CT, especially the hill towns. In southern CT, lower amounts are expected, but watch out in SE CT where there could be a sneaky period of enhancement.
Thursday-Friday Potential
Ok, this is one that has trended all over the place. Just two days ago, this looked like a signifiant winter storm on the guidance. Since then the models have all but dropped it, that is until earlier today, when the GFS and the GFS AI at least for that run brought it back. Some.
This is a trend gif showing what the GFS has predicted for the same Thursday evening for the last two days.
This would normally be a minor event at best, but the timing is the worst it could possibly be. Not only will we have black ice given the melting today and refreezing that is happening tonight, the snow is coming in right during the AM commute. As a result, we will likely see widespread delays and some cancellations tomorrow morning. Because the snow is likely to last into the late morning that may make it tough for some school districts to make a call on delay vs cancellation, though I am guessing that losing two days already will make folks want to get the school day in badly.
By the afternoon we're fine, but the timing is rough. Expect a limited but moderate impact on the roads tomorrow.
As for the snowfall totals, again, we're expecting a general 1-3". Given the race between the precipitation and temperatures, I expect the most snow to fall in northern CT, especially the hill towns. In southern CT, lower amounts are expected, but watch out in SE CT where there could be a sneaky period of enhancement.
Thursday-Friday Potential
Ok, this is one that has trended all over the place. Just two days ago, this looked like a signifiant winter storm on the guidance. Since then the models have all but dropped it, that is until earlier today, when the GFS and the GFS AI at least for that run brought it back. Some.
This is a trend gif showing what the GFS has predicted for the same Thursday evening for the last two days.
As you can see, it went from pretty big storm to out to sea to maybe some light snow. Here's what the Euro has done. After also projecting a big storm the Euro and its AI version want nothing to do with it.
What does this mean? It means there is some fairly high uncertainty on what will happen Thursday night into Friday. At this time, it looks like a miss overall, or glancing blow at worst. The model runs tonight and tomorrow should settle it.
What's the deal with next week?
Earlier today I saw that the hype machine was already going somehow about next week. We always give the same caveat that a week away is an eternity, but what are we seeing?
At least right now, the models are signaling that a storm will develop in the Midwest and quickly get shunted east. With us being the battleground between warmth and cold that likely means that the storm will target our general area. Below is are the GFS and Euro ensembles. Note the shade near our region, which depicts lower pressures. This is a fairly strong signal for some type of storm.
The EPS is on top and the GEFS is on the bottom.
What's the deal with next week?
Earlier today I saw that the hype machine was already going somehow about next week. We always give the same caveat that a week away is an eternity, but what are we seeing?
At least right now, the models are signaling that a storm will develop in the Midwest and quickly get shunted east. With us being the battleground between warmth and cold that likely means that the storm will target our general area. Below is are the GFS and Euro ensembles. Note the shade near our region, which depicts lower pressures. This is a fairly strong signal for some type of storm.
The EPS is on top and the GEFS is on the bottom.
All we know at this point is that a storm is possible, but anything putting out snowfall projections or even model maps like the one below. It's hype...for now...
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Thank you for reading SCW.
-DB
Thank you for reading SCW.
-DB
