Good evening from Southern Connecticut Weather.
Yeah, I may not get much sleep for the foreseeable future.
From time to time we've heard discussion and speculation on various favorable patterns for winter storms. More often than not, the pretty colors aloft on computer models have failed to produce in reality. In fact, just last month, a very favorable pattern for winter storms failed in spectacular fashion, as we had repeated Arctic blasts suppress storms. Cold and dry. That's changing in a big way.
Overall Pattern
I am still somewhat skeptical about the true nature of the potential the next few weeks, but what cannot be denied is that we've seen gradual but substantial hemispheric changes that have now put us in this possible Goldilocks Zone for a wintry stretch not often seen in the region.
At this moment in time at least, it looks like we will be on the wintry side of a "gradient pattern", a pattern that has a clash between warmer air to the south and frequently reinforced colder air to the north. Along that boundary storms can develop bringing snow, mixed bag systems, and rain.
There are a few things that are critical for the period ahead. First, being on the cold side of this gradient means that storms will be more wintry than wet. Second, and we already see it, the initial part of this pattern is going to be fast. Everything gets focused along this gradient, which means that there will be a lot of storms. This isn't like January where we're waiting for windows to open. The window is wide open and storms are coming. Where the gradient is when they arrive is what matters for the type of storm. Third, later on in the pattern the guidance is in complete agreement that there will be blocking in the Atlantic. As we know, blocking can be a double edged sword. In January, it suppressed systems because of the cold presses. Here, it could bring consistent cold and allow for a slowdown of storms along the gradient, raising the chances for big storms by around mid-month.
The ensembles have responded to this pattern potential with a cross guidance signal for a high end period of snow. We're talking feet over the next few weeks, folks. We'll see if it happens, but I have increasing confidence that this month could produce a blockbuster amount of snow.
For reference, Hartford (BDL) averages 14.8" of snow in February. Bridgeport (BDL) averages 10.7". February is our snowiest month.
Now on to our next storm, which has already triggered winter storm watches for the entire state--the first time this season.
Yeah, I may not get much sleep for the foreseeable future.
From time to time we've heard discussion and speculation on various favorable patterns for winter storms. More often than not, the pretty colors aloft on computer models have failed to produce in reality. In fact, just last month, a very favorable pattern for winter storms failed in spectacular fashion, as we had repeated Arctic blasts suppress storms. Cold and dry. That's changing in a big way.
Overall Pattern
I am still somewhat skeptical about the true nature of the potential the next few weeks, but what cannot be denied is that we've seen gradual but substantial hemispheric changes that have now put us in this possible Goldilocks Zone for a wintry stretch not often seen in the region.
At this moment in time at least, it looks like we will be on the wintry side of a "gradient pattern", a pattern that has a clash between warmer air to the south and frequently reinforced colder air to the north. Along that boundary storms can develop bringing snow, mixed bag systems, and rain.
There are a few things that are critical for the period ahead. First, being on the cold side of this gradient means that storms will be more wintry than wet. Second, and we already see it, the initial part of this pattern is going to be fast. Everything gets focused along this gradient, which means that there will be a lot of storms. This isn't like January where we're waiting for windows to open. The window is wide open and storms are coming. Where the gradient is when they arrive is what matters for the type of storm. Third, later on in the pattern the guidance is in complete agreement that there will be blocking in the Atlantic. As we know, blocking can be a double edged sword. In January, it suppressed systems because of the cold presses. Here, it could bring consistent cold and allow for a slowdown of storms along the gradient, raising the chances for big storms by around mid-month.
The ensembles have responded to this pattern potential with a cross guidance signal for a high end period of snow. We're talking feet over the next few weeks, folks. We'll see if it happens, but I have increasing confidence that this month could produce a blockbuster amount of snow.
For reference, Hartford (BDL) averages 14.8" of snow in February. Bridgeport (BDL) averages 10.7". February is our snowiest month.
Now on to our next storm, which has already triggered winter storm watches for the entire state--the first time this season.
Above: the first call snow map showing a statewide 4-8". While there is upside here, let's get the track and snowfall ratio details in better focus before going any higher.
Overall Setup
I daresay that this is a little easier to forecast. Famous last words. The fundamentals of the setup in the upper levels of the atmosphere are different in critical ways compared to our mixed bag today.
While there is a primary area of low pressure that travels in from the west, it is 1) stronger, and 2) further south. This is critical. A stronger system makes it more dynamic, which gives us a little higher ceiling compared to the other storms we've had this season. The system being further south is obviously critical, as that helps keep each level of the atmosphere colder. Today we had a low well to our northwest bring southerly flow erode the cold aloft inland and even at the surface in southern CT. Having a further south and consolidated track, as we get our press of cold move into the region tomorrow, would greatly increase snow potential.
The models generally agree on the evolution (not details), and here's an example of that evolution on the latest GFS.
I daresay that this is a little easier to forecast. Famous last words. The fundamentals of the setup in the upper levels of the atmosphere are different in critical ways compared to our mixed bag today.
While there is a primary area of low pressure that travels in from the west, it is 1) stronger, and 2) further south. This is critical. A stronger system makes it more dynamic, which gives us a little higher ceiling compared to the other storms we've had this season. The system being further south is obviously critical, as that helps keep each level of the atmosphere colder. Today we had a low well to our northwest bring southerly flow erode the cold aloft inland and even at the surface in southern CT. Having a further south and consolidated track, as we get our press of cold move into the region tomorrow, would greatly increase snow potential.
The models generally agree on the evolution (not details), and here's an example of that evolution on the latest GFS.
If you are in coastal CT, that mix line is a little closer that you'd probably like, and it complicates my forecast a bit, but the cold in place should make this system mostly, if not all, snow.
Above: the 12z Euro depiction of the weekend storm system.
The Forecast
Timing
The guidance has come into much better agreement on timing, though there are still some differences. Because of the pattern, this is another fast mover. Right now, it looks like Saturday activities will be fine most of the day. Snow is likely to start between 6-10pm, but this may get tweaked. The heaviest snow looks to occur during the overnight and early morning hours. The biggest difference between the guidance is that the Euro tries to hang onto snow into the early afternoon of Super Bowl Sunday, while other guidance is faster. I lean faster in this scenario, and I think that by late morning Sunday the storm will have passed. Travel late Saturday into early Sunday will be tough.
Snowfall Accumulation
As I mentioned earlier, I am starting with a general 4-8" statewide. As it stands, I think most see 5-8", but I want to account for possible mixing along the immediate coast due to track, a faster forward speed of the system, or last minute weakening trends on the guidance. That's a long winded way of saying that while likely significant statewide, I want to see more details on the intensity of the system and speed before contemplating something like 5-10" or 6-12". This looks like a significant winter storm, even if it is a fast mover.
Impact
The timing reduces the impact some. The heaviest snow is likely late night/early morning, and the storm is likely to be out of here long before the Super Bowl parties begin. That said, a widespread 5-8 (+) would be impactful no matter what. I don't envision much wind, and because indications are that we will see a cold storm, I'm expecting a more powdery snow. This should be a moderate impact storm, with the chance it becomes higher impact if we see a trend toward more snow.
There won't be much rest. After this storm ends Sunday, another snowstorm will be on its heels, arriving as early as Tuesday...
As always, please like, share, and interact with us on our social media--on Facebook to share our discussions, and follow us on Twitter @southernctwx to retweet our posts. Hit the buttons below to join.
Thank you for reading SCW.
-DB
Timing
The guidance has come into much better agreement on timing, though there are still some differences. Because of the pattern, this is another fast mover. Right now, it looks like Saturday activities will be fine most of the day. Snow is likely to start between 6-10pm, but this may get tweaked. The heaviest snow looks to occur during the overnight and early morning hours. The biggest difference between the guidance is that the Euro tries to hang onto snow into the early afternoon of Super Bowl Sunday, while other guidance is faster. I lean faster in this scenario, and I think that by late morning Sunday the storm will have passed. Travel late Saturday into early Sunday will be tough.
Snowfall Accumulation
As I mentioned earlier, I am starting with a general 4-8" statewide. As it stands, I think most see 5-8", but I want to account for possible mixing along the immediate coast due to track, a faster forward speed of the system, or last minute weakening trends on the guidance. That's a long winded way of saying that while likely significant statewide, I want to see more details on the intensity of the system and speed before contemplating something like 5-10" or 6-12". This looks like a significant winter storm, even if it is a fast mover.
Impact
The timing reduces the impact some. The heaviest snow is likely late night/early morning, and the storm is likely to be out of here long before the Super Bowl parties begin. That said, a widespread 5-8 (+) would be impactful no matter what. I don't envision much wind, and because indications are that we will see a cold storm, I'm expecting a more powdery snow. This should be a moderate impact storm, with the chance it becomes higher impact if we see a trend toward more snow.
There won't be much rest. After this storm ends Sunday, another snowstorm will be on its heels, arriving as early as Tuesday...
As always, please like, share, and interact with us on our social media--on Facebook to share our discussions, and follow us on Twitter @southernctwx to retweet our posts. Hit the buttons below to join.
Thank you for reading SCW.
-DB
