Good evening from Southern Connecticut Weather! 

The big story the last few days has been the wind in the wake of our significant rainstorm, and while the breezy conditions will linger, the story of the week ahead will be the warmth. This should be a fairly quick forecast, so let's dive in! 

Above: the 18z EPS showing temperature anomalies for the week. We will be mostly above to well above normal in temperatures, with Wednesday and Thursday bringing a little more complexity. 

Monday-Tuesday
The next two days should be quite nice, finally giving us a good taste of spring as temperatures reach the upper 50s to low 60s. We will have plenty of sun, and while it may be a little breezy Monday, as high pressure builds in the winds won't be an issue. Tuesday should be in the same ballpark in terms of temperatures, and it will feel great with temperatures near 60 and abundant sunshine. Keep in mind however that with clear skies, we will see some cold nights for this time of year with lows in the 30s as radiational cooling will be possible each night. 

Wednesday-Thursday
This part of the forecast is a little more complicated, as a cold front arrives late Tuesday. I'm not expecting any precipitation with the front late Tuesday/early Wednesday. In the wake of the front however, we will see our daytime temperatures fall, with highs reaching the mid to upper 40s on Wednesday. There will be increasing clouds as we head into Thursday, and the guidance has been consistent in showing a weak system passing through the region.

The models keep most of the precipitation to our north, so I am not expecting much, but there could be some rain/snow showers very early Thursday, followed by a cloudy day. 

Above: the 18z Euro operational showing the weak system crossing the region early Thursday. While there may be some rain and/or snow showers around early Thursday, the system is moisture starved and fast moving, so I don't expect any travel issues in CT. 

Friday-Sunday
Temperatures aren't that bad Wednesday and Thursday in the whole scheme of things, but they are not quite what people think of when you think of spring. After the weak system departs Thursday, we warm right back up as a ridge builds back in. Friday looks nice with highs back into the upper 50s to low 60s, though there's a question of how much cloud cover we will have. 

The same is true for Saturday, which is a big day due to the St. Patrick's Day Parade. Right now, the weather looks good, with cloud cover to be determined. In fact, it's possible that we see highs in the low to mid 60s!

Sunday gets tricky, because there's a relatively high chance that a big storm out west traverses the region. As the storm cuts well to our west, we will be on the warm side and Sunday looks wet as a result. Details will become clearer as the week progresses, but Sunday looks closer to a washout than nuisance showery day. Temperatures remain elevated with highs in the 50s.  

Above: the 00z GFS, depicting a dry day Saturday turning into a very wet Sunday as a storm cuts well to our west. In the wake of this storm, colder air filters back into the region. 

The Dailies
Monday: Mostly sunny and warmer. Highs in the upper 50s to low 60s. 

Tuesday: Mostly sunny. Highs in the upper 50s to low 60s. 

Wednesday: Partly cloudy and cooler with increasing clouds late. Highs in the mid to upper 40s. 

Thursday: Mostly cloudy with a chance of rain and snow showers. Highs in the mid to upper 40s. Chance of precipitation 30%. 

Friday: Partly cloudy and warmer. Highs in the upper 50s to low 60s. 

Saturday: Partly cloudy. Highs in the low to mid 60s. 

Sunday: Increasing clouds early with rain, heavy at times, by afternoon. Highs in the low to mid 50s. Chance of rain 70%. 

​A​s 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.
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Thank you for reading SCW. 

-DB

Good evening from Southern Connecticut Weather! 

Winter gave us its best shot in February, but still failed to deliver enough snowfall to bring us within striking distance of a normal snowfall winter. Although it felt cold in February with several Arctic blasts, temperatures actually finished within a degree of normal--another reminder that we've had some real blowtorch winters recently that have altered our perspective of what a normal winter actually is. 

Every year is different. Sometimes winter doesn't arrive, while other winters loosen their grip early or late. No matter what however, at some point we begin a march toward (sustained) spring in our sensible weather. Although sustained spring is not quite on the horizon, we've reached the point where we can now say that the worst of winter is over, and we are marching toward spring. 

Above: the 12z European ensemble showing temperature anomalies at the surface over the forecast period. Although we're much colder than normal tomorrow, we quickly rebound back to warmer conditions for most of the week until another cold shot next weekend. 

Monday
Keep in mind that at this point in March the average high and low in Hartford (BDL) is 43/25, while at Bridgeport it is 44/29.

March is a month where we see significant gains in daylight and average temperatures, and while a well timed shot of cold could easily bring snow in any part of the month, by March 15 the average high and low is 47/28 at Hartford and 47/32 at Bridgeport while the last day of March averages 53/33 at Hartford and 52/37 at Bridgeport. 

There will be no warmth on Monday. Our brief Arctic shot gradually eases, and some inland areas could be below freezing again after a very cold morning start for this time of year. At least it will be sunny with a slight breeze. 

Tuesday
Tuesday will return us to a warmer than normal regime, with temperatures rebounding into the upper 40s. It'll also be a sunny day, so it should be enjoyable. The quiet weather ends here, as a significant storm develops and cuts well to our west on Wednesday. Tuesday night looks dry at this time. 

Wednesday-Thursday
Our midweek storm should arrive by Wednesday morning, and while it will be warm, it will be windy. I expect some wind advisories for Wednesday and perhaps Thursday, but I'm not expecting major winds in the whole scheme of things. As a result, I am not expecting significant power outages at this time. 

The bulk of the rain looks to be Wednesday afternoon and evening, though some rain showers are also possible early Thursday. Wednesday and Thursday should have highs in the mid to upper 50s. 

Above: 18z Euro depicting the storm passing on Wednesday-Thursday. Rain will be heavy at times. 

Friday-Sunday
The end of the week looks quieter, with Friday a touch cooler but more sunny (it may get windy in the wake of the storm, however) and the weekend bringing the chance of more precipitation on Saturday as a weak system moves through the region.

There may be enough cold air for some snowflakes to fly in addition to the rain in northern CT, but for now I will just have rain chances. Temperatures look near normal Friday and Saturday, with Sunday likely a bit colder. Longer term, we're probably dealing with seesawing temperatures and modestly active conditions until about mid-March when it looks like we start seeing some more consistent warmth. Warmth is relative, folks. I don't think 70s and 80s (which would be well above normal this time of year) are marching through the door yet. 

Above: the GFS depiction of a weak system moving through the region Saturday. The track is too far north to bring much, if any, wintry precipitation, but if there is a further south track some snow would be possible. 

The Dailies
Monday: Mostly sunny and cold. Highs in the low to mid 30s. 

Tuesday: Mostly sunny and warmer. Highs in the low to mid 40s. 

Wednesday: Mostly cloudy with rain, heavy at times. Windy. Highs in the mid to upper 50s. Chance of rain 90%. 

Thursday: Mostly cloudy early with rain showers. Breezy. Highs in the mid to upper 50s. Chance of rain 50%. 

Friday: Mostly sunny and cooler. Highs in the low to mid 40s. Chance of snow showers 10%. 

Saturday: Partly sunny with rain showers. Highs in the upper 30s to low 40s. Chance of rain 40%. 

Sunday: Mostly sunny, breezy, and seasonably chilly. Highs in the upper 30s to low 40s. 

​A​s 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.
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Thank you for reading SCW. 

-DB

Good afternoon from Southern Connecticut Weather. 

There wasn't a lot of sleep in the last few weeks as winter gave us its best shot. This latest storm was the most impactful, with snow, ice, rain, and wind on the backside of it. How did our forecast hold up? We submit our final grade below, and illustrate why the social media hype you may have seen elsewhere for a possible storm on Thursday took off...and was wrong.

Above: the verification map for the winter storm. Note that this includes measured snow and sleet (which officially counts as snow) from published National Weather Service reports. 

Grading the Forecast
Timing
As I mentioned in the final call forecast, the timing was trickier than I would have liked, both for the start time and the evolution of the warm air. We were fortunately right that the morning and afternoon would be fine, so that's good, but the onset of the snow happened fast.

We had snow break out from 3-7pm. First flake reports started coming in at 2:30pm, which isn't bad but worth a minor deduction. What was the bigger issue with start time was that the snow rapidly moved across the state, hitting eastern CT faster than expected. Many were snowing by 5pm, so this range was too large. 

Now for the changeover to mixing. We did say that we expected mixing to occur in SW CT between 10pm and midnight, and the mixing happened between 9-10pm. Not bad. Not perfect. However, we did also say that most of southern CT would be rain by early Sunday morning. That was partly right--but there wasn't enough specificity about it.

For northern CT, we were spot on, even identifying the potential for a mesolow to lock in colder air. We were also spot on about the rain timing window and wind timing. 

As mentioned above, there needed to be some deduction for a faster onset of the snow and slower erosion of the cold in part of southern CT, but this was pretty good overall. 

Grade: A-

Snow & Ice Accumulation 
​As you saw with the accumulation map above, we were spot on. It was the best map of the season, and the fact that this was the highest impact and most tricky forecast makes me proud. I'm even proud of where we set up the dividing line, though I probably could have pushed it slightly north.  

We had plenty of cold to start as snow, and as expected the warm air aloft did erode the cold. The surface cold was hardest to dislodge in northern CT, and NW CT struggled along with much of northern CT to get above freezing. However, there was much more cold than expected in southern CT away from the immediate coast, and as a result there was more freezing rain there. 

For southern CT, we did anticipate a general 1-3" of snow and sleet, along with a glaze of freezing rain before a flip to rain. It would have been more helpful to be more specific with the freezing rain amounts, because as I look back, a glaze implies minimal icing and that was not the case. The trick here is, what's significant? For me, .1 or .2 of ice is essentially a glaze to me, while .25 and above is more meaningful. It's something to remember whenever we have another icing event on the table. 

For northern CT, the guidance was all over the place but we went with 2-5 rather than 2-4" or a general 1-3 statewide. Great call. As expected, few saw 5", but the high ceiling for a colder storm turned out to be right as we had an isolated number of reports above 5". What's most important in all of this is that I did communicate that ice, not snow, was the story of this storm. 

The map carries us here, which is all that folks care about I know. However, there needed to be some deduction for lack of clarity. I'm not sure we could have anticipated the amount of cold in southern CT at the time of the forecast given the data we had, but to our credit, we did put it in multiple live updates in advance of the storm--so it should not have been as much as a surprise to readers. 

Grade: A-

Wind & Power Outages
It was a good call saying that we wouldn't have many wind issues during the storm. That proved to be right given the wind reports we saw. We got our significant wind in the wake of the storm and today. Because of the ice, we saw isolated to locally scattered outages. While overall, we had maybe 1-2% of the state without power--isolated overall--we did have some communities with higher concentrations of outages. That worked well with the forecast. 

Not much else to add here. It was spot on. 

Grade: A

Overall Impact
This is another bright spot for the forecast. I considered saying that this would be moderate impact in southern CT, but stayed away from that given the colder storm potential and forecast this as a high impact event statewide. We had numerous events canceled during the weekend, and the combination of snow, sleet, freezing rain, and heavy rain causing localized flooding did make things a mess. The road conditions were mostly right--though I should have called for more icy roads into the morning in southern CT. Great job overall. 

Grade: A

Final Grade
You have no idea how good it does my heart to know that the toughest storm of the season so far had the best forecast of the season. On little sleep!

Yes, there are always ways that we can improve. That is why we do these reviews. There is no perfect forecast. I could have been more specific with expected freezing rain accumulations, and the onset timing could have been forecasted better, but everyone that read the final call forecast knew to expect a high impact event statewide Saturday and Sunday.

Although it doesn't get graded, the live updates continue to prove that they add enormous value, given that we needed to "nowcast" the erosion of the cold and several waves of precipitation. For once, having the snow accumulation forecast weighed twice helps rather than hurts the final grade! 

Final Grade: A-

Now let's talk about something not so good--the social media hype surrounding the next storm in the pipeline...

Above: one of the images that was circulating social media in recent days about the possibility of a historic storm this week. On this image, "snow potential" was for Hartford to have nearly 35" of snow by Friday! Oops. 

Hype Sells but is Often Wrong
SCW has built its reputation on no-nonsense weather forecasting and discussion, and as a practice, we don't take shots at others that forecast. It's hard stuff. We don't pay attention to what anyone else is doing really, with the exception of the National Weather Service because they issue watches and warnings (and have high resolution models that are helpful). 

However, we often quietly bat down the hype that we see on social media. When talking about hype here, we're not talking about a bad forecast--which happens. We're talking about people that are intentionally trying to rile people up and/or share information in bad faith.

This time, I want to take a look at why the image above and the other calls you may have seen for an epic event coming this week turned out to be wrong, and why at each step better decisions could have been made. 

The Hype Cycle

Step 1: Find the Kernel of Truth
Like most garbage on social media, it probably has some kernel of truth--or at least the appearance of it. If you've been following our forecasts, we noted on Friday, February 14, that there was storm potential for the coming week. We kept it vague as we usually do at this time range, because while you can see storm potential 6-10 days out, you cannot see details.

This is what we said in the final call forecast that we issued that Friday: 

There will be plenty of cold, which will lead us to the next storm in the pipeline.

There is zero reason to get excited about or dread a possible storm next week. At this time, we do have higher than usual confidence that something will develop. Because there is going to be cold air in place and likely blocking in the Atlantic, we know it is highly unlikely to cut like this weekend storm. We have moderate confidence that the timing for a storm would be late Wednesday or Thursday. We do not know track and storm evolution. This could easily miss because of a poorly timed phase--just like that blizzard we missed out on a month ago. This could be a messy phase that brings us another modest snowfall. It could be a big dog blizzard. There's no real reason to do anything other than look at next week with a casual eye and avoid the hype on social media and elsewhere. Let's see where we are Sunday before taking anything related to next week seriously.  

We intentionally don't show snow maps or the most extreme versions of these models because they are useless. A good forecaster knows not to use them--especially at this range. 

The signal that a storm likely developing somewhere was the kernel of truth. But that's not enough to go all in on a historic event. 

Step 2: Show Extreme Potential
Sometimes, there is legitimately extreme potential that should be communicated. Most of the time however, models are either over amplified or "overwhelmed" in analyzing the nuances and chaos of numerical weather prediction at longer or even medium range. They start out extreme, but naturally modify to something far more mundane more often than not.

Here, a good forecaster knows to wait to see if there's a shift in the fundamental elements of a forecast that make an extreme solution more or less likely. In our text above, we note the potential of a poorly timed phase or a messy phase, along with the big dog possibility (but note we don't talk about snow totals intentionally). We don't post a snow map with specific numbers and say it's not a forecast. In our opinion, sharing that kind of stuff does more harm than good, and should only happen when you're at high confidence for an event to hit. 

For others, those more likely scenarios don't get serious consideration. So what was a kernel of truth--a big storm is possible--gets twisted into the most extreme computer model run possible and becomes the only thing that is shared and seen because it's shocking to look at. 

And the result is what we would expect. 

Above: this was the extreme GFS operational model forecast for total snow by this Friday. This model run was 7.5 days in advance of Friday. This much snow in one storm is almost unprecedented, which is a red flag in itself. 

Here's a trend loop for that same snapshot in time. Look at how the snow forecast changes as we get closer to reality. It's basically zero now. Note that some of this included snow from the weekend storm, but the picture is all the same. 

Step 3: The Truth Arrives Too Late
By the time someone is sharing a computer model showing 35" of snow in a week, or a hurricane hitting New Haven, or super high end tornado parameters in Connecticut, real analysis and truth go into hiding. We're playing whack-a-mole with questions about what's actually going to happen. 

Eventually the truth arrives because there's no mega blizzard, or hurricane, or tornado outbreak, but not before a lot of people are left confused and concerned.

One of the fundamental things about weather forecasting is understanding that most people do not follow it the same way that we do. Concepts like phasing, tropospheric polar vortex, and teleconnections are not understood at a detailed level by a small business owner or family, nor should they be. It's our job to bring thoughtful analysis to the table to help people be informed. 

Just looking at the 500mb pattern should have told many that the mega blizzard idea up the Eastern Seaboard was going to be tough, especially if folks waited for more information. 

Above: the last 15 runs of the GFS model looking at the overall pattern at 500mb. Note all of the changes that happen run to run--these make a huge difference in what happens here.

Ok, so what's happening this week?
Now for some reality.

A mega blizzard is not happening this week--though you probably know that by now because there aren't any new computer models showing a blizzard being shared. The kernel of truth was in fact truth--a significant storm is likely to form, but because of a missed connection between the northern stream and southern stream of the Jet Stream, the storm slides well south of our region, and becomes a significant storm well out to sea.

As a result, the next storm in the pipeline is most likely a miss--with light snow on Thursday possible if an inverted trough develops. This gives us all a much needed break from stormy weather, though the Arctic cold will be with us for most of the week ahead. The pattern still looks active, but for now, not at the same pace as the last two weeks. 

The storm was real. The hype was wrong. 

A​s 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

Good evening from Southern Connecticut Weather. 

Winter weather advisories are up once again for all of Connecticut as the latest storm in our extremely active pattern approaches. This one, like most of the others, will be a mixed bag system, with snow, sleet, freezing rain, and rain for the state over most of the weekend. Let's get right to it. There's a lot to discuss, including a look at big wind potential Monday, another Arctic blast, and the next potential storm in the pipeline.

Above: the snow and ice map for our upcoming storm. For southern CT, I expect a general 1-3" of snow and sleet, followed by a glaze of ice especially inland. For northern CT it gets more tricky, with 2-5" of snow and sleet expected and a glaze of ice for most. In NW CT, really most of Litchfield County, there is a greater risk of modest ice accumulation via freezing rain on Sunday. 

Overall Setup
We've been watching this storm closely the last few days, and while the general setup is now relatively straightforward, the devil is in the details.

Unlike our last few systems of middling strength, this is a big dog. A low pressure system will eject from the south, and rapidly intensify as it tracks northeast. Because there is no real Atlantic blocking to shunt it out to sea up under our region, with will cut to our west as it intensifies. That means we rain eventually. 

However, there is a relatively deep level of cold air in place, and that will ensure that the front end of the system will produce snow and ice. Importantly, this storm will try to spawn a mesolow off the coast that would lock in colder air as precipitation runs over the region, but that is something we will need to watch for as the storm evolves. Rather than the original thought of two separate waves this weekend, there's really only one big storm. Note the surface pressure in the 975mb range over near Buffalo and the expanse of the snow on the NW side of the low. This is a sprawling and powerful storm, that will influence the wind potential after it departs Monday and drag in our latest Arctic blast. 

The GFS below illustrates the storm evolution and the cold air advection Monday morning. 

The Forecast
Timing
This is trickier than I'd like because there is a bit of a discrepancy in the high resolution models for when this starts. Tomorrow morning and early afternoon look fine statewide. If you have morning and even early afternoon activities or travel plans, they will be fine. However, snow will break out statewide tomorrow afternoon. I think we see snow start out light for the state from west to east between approximately 3-7pm. The earliest start time will be in western CT, with the start of the storm during the middle part of that time frame in central CT, and latter part of that time frame in eastern CT. 

The snow will be moderate at times, and given the cold that will be in place tomorrow expect road conditions to deteriorate as the snow continues. It will snow statewide most of tomorrow. As the cold air aloft erodes, we will see the mix line start to creep into CT. In southwest CT, it will happen the earliest, with a flip from snow to sleet likely between about 10pm to midnight. Once this mix line starts showing up, it will blast its way through much of southern CT, turning most of southern CT to rain by early Sunday morning. 

However, for northern CT, that mixing will be hard to dislodge during the early morning hours. That will give the area an extended period of sleet and then potentially freezing rain. In NW CT especially, surface cold will be hard to dislodge, so there's a chance icing continues into the day Sunday there, and across much of northern CT if the mesolow develops fast enough to lock in the cold for longer. 

At any rate, warmth eventually wins with this storm for most if not all of the state. By Sunday afternoon and night we will likely have periods of moderate to heavy rain moving through the state until the storm passes and winds start to ramp up in its wake. Monday will be clear, but it will be very windy. 

Snow & Ice Accumulation 
​If you look at the image below, this is basically how the storm will play out over time. 

We will start with cold air at the surface and aloft across the entire state. That's why we will start off as snow. Over time tomorrow, warm air aloft will erode the cold, changing us to sleet. As more warmth moves in as the storm intensifies to our west, then we will see freezing rain. The surface cold will be hardest to dislodge in northern CT, which is why freezing rain will likely last longer here than in southern CT. Once the warmth has overwhelmed the entire column, we rain.  

This makes the snow and ice accumulation forecast tricky. Along the coast, you honestly want more snow than ice, which means you want heavy enough precipitation to keep the column cool as long as possible before warmth arrives.

For southern CT, I anticipate a general 1-3" of snow and sleet, along with a glaze of freezing rain before a flip to rain. The lowest snow amounts are likely in coastal SW and SE CT, with more snow and sleet the further inland you are. 

For northern CT, the guidance is all over the place. My best call is a general 2-5". I doubt many see 5". I want a high ceiling for if this trends colder. I think most likely land in the 2-4" zone.

It's really important to note that I'm intentional in setting these ceilings and floors. It's not going to be a bust if most of the state is 1-2" of snow--that would likely mean that there's fairly substantial icing in the form of sleet (which accumulates much less efficiently like snow) and freezing rain. The ice is the story for this storm.

Less snow and more ice as I described above is probably the highest impact and worst case scenario. It is on the table, but I expect more cold in place for more measurable snow and some ice.

Below is the latest high resolution NAM depiction, showing the difficulty in getting the cold air in CT totally eroded. There will be places in southern CT on Sunday that rocket their way into the 40s, while parts of northern CT will be struggling to cross the freezing mark, especially early.

This is a very tricky setup.  

Wind & Power Outages
Overall, being on the warm side of this storm isn't going to cause a lot of wind issues early. In fact, for most of the storm I'm not expecting significant wind. However, in the wake of the storm we are likely to get a significant period of wind on Monday. That's going to be discussed later since it's post storm. 

With possible icing in interior CT however, wind on Monday will be something to watch. The ice by itself doesn't look to be major, but there could be some isolated to scattered outages on Sunday, and more scattered outages on Monday depending on whether we can get the higher winds to verify. 

Overall Impact
This is a high impact event. To be clear--it's not a let's panic and go get bread and milk storm, but it's high impact because most events will likely be canceled for later Saturday and into Sunday, even though it'll likely be fairly warm in southern CT eventually. Flights will likely get delayed between Saturday evening and Sunday early afternoon.

The snow by itself isn't bad, but the combination of snow (which could be moderate at times statewide on Saturday), sleet and freezing rain especially inland, and the prospect of heavy rain and snowmelt on Sunday that could cause some localized flooding issues, makes this a messy event.

Road conditions will not be great for northern CT on late Saturday afternoon/evening into much of Sunday. In southern CT, road conditions will not be great Saturday afternoon/evening into Sunday morning in terms of snow/ice. Wet roads will be a thing late Sunday morning and through the evening. 

Because of the timing of the storm and winds after, there is the chance of widespread delays Monday morning, but it's a little early to lock that in. I just need to note it here because the potential is there. 

Looking Ahead
I will do this very quickly, since the weekend storm is the main focus. We're nowhere close to being done with this active wintry pattern. It's likely to last until at least early March. There is no early spring likely this year. 

As I mentioned above, Monday we are likely to see a very windy day in the wake of our storm. Right now, I think we see wind advisories for gusts of 45-50mph statewide, but there is a signal for greater wind potential on Monday. If that happens, power outages will become more likely. Stay tuned to for additional updates as that comes into greater focus. 

One thing is a guarantee: we get Arctic cold in the wake of this big weekend storm. Expect high temperatures well below normal, with the chance we string together some days below freezing. This time of year, temperatures start to rebound. Believe it or not, the average high/low temperature in Hartford in mid February is 38/20, while it's 40/25 in Bridgeport.  

The Arctic blast will be much worse to our west, but it'll be plenty cold here. Below is a European ensemble 5 day averaged temperature departure next week. 

There will be plenty of cold, which will lead us to the next storm in the pipeline.

There is zero reason to get excited about or dread a possible storm next week. At this time, we do have higher than usual confidence that something will develop. Because there is going to be cold air in place and likely blocking in the Atlantic, we know it is highly unlikely to cut like this weekend storm. We have moderate confidence that the timing for a storm would be late Wednesday or Thursday. We do not know track and storm evolution. This could easily miss because of a poorly timed phase--just like that blizzard we missed out on a month ago. This could be a messy phase that brings us another modest snowfall. It could be a big dog blizzard. There's no real reason to do anything other than look at next week with a casual eye and avoid the hype on social media and elsewhere. Let's see where we are Sunday before taking anything related to next week seriously. 

Above: the GFS from this afternoon showing a miss next week. 

Below: the Euro showing a messy phase leading to a modest storm next week. ​

Nothing to be riled up about. At all.

Yet. 

​A​s 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.
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Thank you for reading SCW. 

-DB

Good evening from Southern Connecticut Weather. 

Busy times. 

Tonight we're dealing with a close scrape from a storm to the south (Storm One) and the second storm this week (Storm Two) is already on its heels. A mixed bag is on tap for our Thursday, and because of the timing there is likely to be some impact. Storm Three is waiting this weekend. Let's dive in. 

Above: a snapshot of the high resolution NAM, showing mixed precipitation in northern Connecticut and rain in southern CT around 4am Thursday morning.

Storm Two (Late Wednesday-Thursday)
In this pattern you should expect some of everything: hits, misses, snow, rain, and mixed precipitation. Literally. The fast flow in the atmosphere moves storms along very quickly, while the oscillating temperature gradient between warm and cold makes precipitation type for each system tricky. 

Storm Two has trended weaker over the last few days, which has a big impact on conditions and impact. If it were stronger, we'd likely be able to hold more cold in place as warm air tried to erode the cold, but with a weaker storm and lighter precipitation, we can't get enough cooling to hold off the rain. 

There will still be enough cold late tomorrow for things to start off as snow, but that snow will be light and quickly change over. In southern CT, it will quickly go from snow (a coating) to mix to rain, while inland areas will hold onto mixing a little longer on Thursday. 

The NAM below depicts this well, showing a period of snow starting between approximately 8-10pm Wednesday night, followed by a change to mix and then rain Thursday morning. 

Because of the timing, this weak storm will have some impact, especially inland. Unlike last week, the cold is unlikely to hang on as long.

For southern Connecticut, expect a coating of snow and a light glaze of ice Wednesday night into early Thursday. By sunrise it will be a plain rain. As a result, the impact looks low, and while widespread delays are possible I do not think they are likely. 

For northern Connecticut, we could see a coating to an inch or isolated two spot before a glaze of ice. While some guidance shows a change to rain, it's possible that a dry slot moves in before there is meaningful rainfall. Because mixing could continue past sunrise in northern CT, widespread delays look likely, and cancellations are possible. 

This is a fast mover, so the PM commute although wet, shouldn't be too bad. 

Storm Three (Saturday-Sunday)
The final storm of the week continues to have the biggest potential, but there's a lot of uncertainty over whether it will be a significant rain event (1"+) or a wintry storm. 

This one is tricky, and it's a lot about timing. A piece of Arctic air is trying to move toward the region as the weekend storm develops. Recent guidance has backed off a significant cold press leading to another mixed bag to rain system. There is a lot that can still change with this, so it's not worth going into too much detail yet until some of the major features are more stable, but this looks to be a longer duration storm as a follow up wave tries to develop along the temperature gradient. 

With a colder press, the gradient and thus the low would sag further south, bringing significant snow and/or ice. Without that cold press from the polar vortex, the temperature gradient is further north, and the storm effectively cuts to our west, bringing heavy rain Saturday and Sunday. 

In terms of timing, it looks like onset wants to speed up. Right now, we're looking at snow breaking out early Saturday afternoon, with precipitation likely lasting through Sunday as the follow up wave develops. There are still significant differences between the GFS and Euro. At this time, I think this one brings a snow to mix to rain event. 

GFS, which is much more wintry with snow and potentially significant ice. 

The Euro on the other hand goes from snow to significant amounts of rain during the period. 

There's still a ton to sort out with the weekend. A storm is likely and we will likely have some snow, but how much snow before going to ice or possible rain remains highly uncertain. Stay tuned. 

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Thank you for reading SCW. 

-DB