Good evening from Southern Connecticut Weather.
After a fast start to winter in early December and a thaw during the middle of the month, we are looking at a potential winter storm bringing some impacts to parts of Connecticut to end this month. This is a complex system, and will pose quite a forecasting challenge, so as you read the discussion below I encourage you, especially if you live in northern Connecticut, to remember that this is a forecast that will evolve. Let's dive in.
After a fast start to winter in early December and a thaw during the middle of the month, we are looking at a potential winter storm bringing some impacts to parts of Connecticut to end this month. This is a complex system, and will pose quite a forecasting challenge, so as you read the discussion below I encourage you, especially if you live in northern Connecticut, to remember that this is a forecast that will evolve. Let's dive in.
Here is our ice accretion map for the coming system. We are not expecting accumulating snowfall. Note, as currently forecast we are expecting most to receive icing on the lower end of the forecast, especially for central and southern portions of the icing zones. For southern Connecticut, only rain is expected.
As mentioned in the title, the northern four counties are under a Winter Storm Watch. Even in these areas, not all locations will receive warning level icing of .50". In fact, as currently projected, I think the majority of folks fall below that threshold.
As mentioned in the title, the northern four counties are under a Winter Storm Watch. Even in these areas, not all locations will receive warning level icing of .50". In fact, as currently projected, I think the majority of folks fall below that threshold.
Overview
A strong area of low pressure that is developing in the Midwest will cut to our west over the next 24 to 48 hours. Tomorrow will be fine most of the day, and by the late afternoon and evening we will see warm air overrun colder air at the surface as high pressure builds in. This system is a bit different in the sense that just about everyone may start off with a cold rain, and then as colder air advects into New England we see a switch to mixed precipitation of sleet and freezing rain in our highlighted areas. Late Monday we will see this low "redevelop" off the coast, but with a poor airmass it is not looking like we see a flip to snow but rather a potential period of more widespread mixed precipitation. The storm should be over by the Tuesday morning, and while there might be some lingering showers and snow showers, New Year's Eve activities look fine statewide.
There is significant uncertainty that remains over how far southwest that cold air will filter down into Connecticut. That will not be resolved tonight, and will need to be monitored closely over the next 24 hours.
A strong area of low pressure that is developing in the Midwest will cut to our west over the next 24 to 48 hours. Tomorrow will be fine most of the day, and by the late afternoon and evening we will see warm air overrun colder air at the surface as high pressure builds in. This system is a bit different in the sense that just about everyone may start off with a cold rain, and then as colder air advects into New England we see a switch to mixed precipitation of sleet and freezing rain in our highlighted areas. Late Monday we will see this low "redevelop" off the coast, but with a poor airmass it is not looking like we see a flip to snow but rather a potential period of more widespread mixed precipitation. The storm should be over by the Tuesday morning, and while there might be some lingering showers and snow showers, New Year's Eve activities look fine statewide.
There is significant uncertainty that remains over how far southwest that cold air will filter down into Connecticut. That will not be resolved tonight, and will need to be monitored closely over the next 24 hours.
Above is the latest high resolution NAM depiction of the storm from about 7pm tomorrow through approximately 1am on Tuesday. Despite the lack of mixed precipitation verbatim on the surface depiction, we are expecting more wintry precipitation because of how guidance tends to underestimate surface cold in these situations. I think freezing rain is most likely because of a relatively thick layer of above freezing temperatures in the column.
Impacts
Icing--No Impact Southern Connecticut/Low-Moderate Inland
There is no impact expected in southern Connecticut when it comes to icing. For our glaze and .10" inch zones, we are expecting a low impact, and in the hilly sections of NW and NE CT we are expecting more of a moderate icing impact. Again, we expect most to fall on the lower end of our zones as of this discussion. We have the higher zones in case we trend at the last minute toward a more impactful event.
Wind--None
I do not expect any significant wind with this storm.
Power Outages--Low
If we see higher icing occur in northern CT, there may be some isolated to scattered power outages, but currently I am not expecting a high end event.
Timing--Low
The storm starts on a Sunday night and although Monday's morning and afternoon commute could be impacted, with kids at home for vacation and many workers doing the same, the roads should be less congested and our crews should be able to keep up with any mixed precipitation that falls outside of the elevated areas of CT.
Road Conditions--Low
In areas where it's just rainy, the normal level of cautions should be exercised. In areas of central CT that do not receive a lot of icing, you should be careful but I expect main roads to be passable. It is the areas that receive prolonged icing that will have a higher (moderate) impact.
Overall, this system will have no winter weather impact in southern Connecticut and a low to moderate (in hilly areas in particular) inland impact. Stay tuned for our forecast tomorrow as we expect details to be sharpened as we get closer to the event.
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
Icing--No Impact Southern Connecticut/Low-Moderate Inland
There is no impact expected in southern Connecticut when it comes to icing. For our glaze and .10" inch zones, we are expecting a low impact, and in the hilly sections of NW and NE CT we are expecting more of a moderate icing impact. Again, we expect most to fall on the lower end of our zones as of this discussion. We have the higher zones in case we trend at the last minute toward a more impactful event.
Wind--None
I do not expect any significant wind with this storm.
Power Outages--Low
If we see higher icing occur in northern CT, there may be some isolated to scattered power outages, but currently I am not expecting a high end event.
Timing--Low
The storm starts on a Sunday night and although Monday's morning and afternoon commute could be impacted, with kids at home for vacation and many workers doing the same, the roads should be less congested and our crews should be able to keep up with any mixed precipitation that falls outside of the elevated areas of CT.
Road Conditions--Low
In areas where it's just rainy, the normal level of cautions should be exercised. In areas of central CT that do not receive a lot of icing, you should be careful but I expect main roads to be passable. It is the areas that receive prolonged icing that will have a higher (moderate) impact.
Overall, this system will have no winter weather impact in southern Connecticut and a low to moderate (in hilly areas in particular) inland impact. Stay tuned for our forecast tomorrow as we expect details to be sharpened as we get closer to the event.
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
