Good afternoon from Southern Connecticut Weather!

After steady showers earlier this morning, conditions have become mostly dry across the state of Connecticut. Currently we have temperatures hovering in the low to mid 40s from northwest to southeast with mostly cloudy conditions, but some breaks from time to time. There are some showers still off to the south and west but I am thinking a majority of the state stays dry through this evening. It looks as though skies will start to clear out across the state and temperatures will drop through the 40s and into the 30s as we head through the midnight hour, with temperatures toward sunrise ranging from the low to mid 30s statewide. So, much cooler conditions than we have been experiencing over the last few days.

For the start of the work, and the end of 2014, temperatures look to become much more frigid as a cold front moves through during the day on Monday. With high temperatures in the Monday-Friday period looking to barely make it into the 30s and lows dropping down into the teen to mid 20s statewide. In the precipitation department, things look to stay mostly dry through the beginning of 2015 up until the beginning of next weekend, but again, things stay cold. The pattern for the next week or so looks to favor suppressing storms to the south, while keeping snow away from the area, bad news for snow lovers.

Looking to next weekend and beyond, we are currently watching a storm system that may impact the area. As of right now, this storm looks to track to the west of the state, bringing warmer air and rain with it. Much too soon to speculate as this area of disturbed weather looks to be about a week out, but as of right now it looks as if we are stuck in a solid cold and dry, warm and wet pattern. Until we get some help from the EPO, AO, NAO, etc, it looks as if this pattern is here to stay through mid month. I wouldn't totally cancel winter just yet, as many memorable winters have been back-loaded with major snowstorms, but things do not look encouraging for snow lovers in the state through the next 2 weeks.

Today is Sunday, the day we usually release a 7 day forecast, here goes:

Tonight:  Clouds early, then clearing. Temps mid to upper 30s. Chance of precip 20%

Monday: Partly cloudy early, then sunny. Early high temperatures in the upper 30s and low 40s, temperatures will plummet throughout the day into the 30s. Chance of precip 10%

Monday night: Clear, temperatures low to mid 20s inland, mid to upper 20s at the shore, Chance of precip  0%

Tuesday: Sunny and cold, temperatures upper 20s to around 30 statewide, chance of precip 0%

Tuesday night: Clear and cold, temps low to mid 20s statewide, chance of precip 0%

Wednesday: Mostly sunny and cold, chance of flurries, temperatures mid to upper 20s statewide, chance of precip 10%

Wednesday night: Clear and cold, temperatures upper teens inland, to low and mid 20s at the shore, Chance of precip 0%

Thursday: Sunny and cold, temperatures mid to upper 20s inland, low 30s at the shore, Chance of precip 0%

Thursday night: Partly cloudy, passing flurry possible, temperatures low to mid 20s statewide, Chance of precip 10%

Friday: Mostly sunny, slightly warmer, temperatures upper 20s inland, low to mid 30s at the shore, Chance of precip 10%

Friday night: Mostly clear early becoming partly cloudy late, temperatures upper 20s inland, low 30s at the shore, chance of precip 10%

Saturday: *watching closely* Clouds moving in with light snow breaking out in the afternoon, changing quickly to rain in the southern half of the state, snow to sleet to freezing rain and plain rain in the northern half of the state. Temperatures in the 30s and rising throughout the day. Chance of precip 40%

Saturday night: *watching closely* Clouds and rain, could still be some leftover freezing rain in the higher elevations, changing to plain rain by midnight. Temperatures in the upper 30s inland and 40s at the shore, still rising. Chance of precip 40%

Sunday: *watching closely* Clouds and rain, clearing in the afternoon,  temperatures in the upper 40s to low 50s statewide, Chance of precip 30%

Sunday night: Clouds early, becoming clear and colder, temps 30-35 statewide, Chance of precip 10%

Have a good rest of your Sunday everyone! Stay tuned for all the updates about this week's weather and the potential disturbance for next weekend. -Tim

Good evening to you from Southern Connecticut Weather!

It’s been a week with little sunshine in Connecticut, and while there is a light at the end of the tunnel, we’ve got one more storm system to get through first that will bring rain and close to record warmth to the state on Christmas Eve/Day. After that, however, we begin a slide that will last for several days into a more wintry like regime, possibly culminating with the first widespread accumulating snowfall of the season! Let’s break down the forecast.

Tomorrow and Wednesday will maximize the gloomy pattern that we’ve seen the last several days as a storm system cuts to our west and brings warmth and rain to the state. Rain will be in the cards for most of the day tomorrow right through Christmas morning, and along with that will come close to record highs, with temps making it into the mid to upper 50s tomorrow evening into Christmas morning before temps fall Thursday afternoon as the storm departs. As shown on the departures map below, this is ten to twenty degrees above normal for this time of year! As the storm pulls away, we’ll see temps drop back down to more seasonable, yet still above normal levels as colder air comes in from the west. Here’s images of the forecast MSLP at 7 PM tomorrow night, the warmest expected temps, the total QPF, and the forecast departures from normal all from the 18z GFS model. Model consensus is excellent for this close in event as far as our area goes so just took a blend of all models.

In general, expecting between one and two inches of rain across the state, although as always, locally higher amounts possible in heavy cells. A slight chance of  thunderstorms is in the cards for Wednesday night into Thursday morning, and while not expected to be at damaging levels, windy temps are expected, with wind gusts in the 30-40 MPH range, especially on Thursday as the low departs. Highs Wednesday and Thursday both in the mid to upper 50s, although Wednesday will see temps rising through most of the day and Thursday will see them falling. Chance of precipitation is 100%.

Behind the storm, we finally say goodbye to the clouds, as Thursday afternoon we will see clearing skies and then by Friday, close full sunshine! Friday and Saturday look like incredible days to get outside and enjoy the sunshine, with highs in the upper 40s to lower 50s expected. Don’t expect it to last though, so enjoy it while you can as clouds build again by Sunday in preparation for our next possible system.

Modeling is in relatively good agreement on a system moving north from the gulf Sunday into Monday, but how it tracks and a result it’s sensible impacts for our region are still very much in question. The 18z GFS has an anafrontal signature to it, bringing a broad wave of moderate precipitation across much of the east coast. Given the cold air in place from the EPO ridge pressing down from the north, this would result in an overrunning snow event for the area, similar in nature perhaps to some of the events we saw last winter with the thermal boundary being set up to the south of our area and the axis of the heaviest precipitation riding up along that boundary. The GFS would be an all snow event for our area, with accumulations for all right down to the shoreline. Here’s an image of the MSLP and precipitation type from the GFS at hour 144, that being 1 PM Monday afternoon.

The 12z EURO, however, paints a different picture. The EURO has this first wave of overrunning much further north and weaker than the GFS, bringing nothing but some light rain showers for the area. It then forms another low in the gulf and brings it west of the area before it runs into the block of cold air and slides east, redeveloping into a coastal low just south of Long Island. Given that the storm tracks further north, more warm air is allowed to intrude, and the end result is a snow to sleet to rain scenario, with little to no accumulation along the coastline and perhaps a slushy few inches inland before a changeover to sleet and finally rain. Here’s an image of the MSLP from the 12z EURO for 7 AM Monday morning, showing the storm tracking up to our west and warmer temperatures as a result.

The GEFS and EURO ensembles support their respective operationals to a degree, although the EUROens are a little south of the op, suggesting a blended compromise between the two operationals might be an optimal forecast for the time being. However, the 12z Canadian and 18z Parallel GFS have no stronger storm at all for the period and only a weak wave of overrunning,  which would result in light rain showers for the region. Given the uncertainty and the seasonal trend we’ve seen this year to deamplify storms, I’m giving  more weight to these solutions than I would ordinarily(considering their relatively poor verification scores overall), and as a result, will keep precipitation chances relatively low for now. Therefore, all factors considered, will forecast a 40% chance of rain and snow for Sunday and a 50% chance of rain and snow for Monday to represent the uncertainties in precipitation type between the EURO and the GFS. As it’s 5-6 days out, won’t go into too much detail re. timing and impacts, but the potential for a moderate event is there. Remember, it’s 5 days out, and considering the shifts we have seen in guidance inside that window so far this season, I wouldn’t expect to see this locked down until later in the week.

Much colder weather is expected throughout the period, with highs generally in the low to mid 40s Sunday and in the low to mid 30s Monday, although this will vary due to the storm track that ends up verifying. Even colder temps come in behind the storm, with temps perhaps not getting out of the 20s next Tuesday.

We’ll update as needed tomorrow and Christmas day, with a full discussion (along with any needed storm disco) on Friday. Until then, Merry Christmas, Happy Holidays, and thanks for reading Southern Connecticut Weather!
-SA

Good evening from Southern Connecticut Weather!

Last night, through this evening, there has been some light to moderate snow throughout the state in association with a low-pressure system off to the east. Little pulses of precipitation have been popping up, especially in the southwestern part of Connecticut. While there has been little to no accumulation, there could still be some slick spots as temperatures sit right around the freezing mark, so be careful as you head out this evening. Currently, conditions across the state are some scattered snow showers with temps right around freezing to slightly above at the shore. As we head through the rest of the evening and overnight hours, areas of light to moderate snow look to persist with temperatures not budging a whole lot. Any snow showers should end before midnight. 

Looking ahead to the abbreviated work and school week (for some), tomorrow looks to be a day which will be slightly warmer than today with temps ranging from the mid to upper 30s inland to the low and mid 40s at the shore. Precipitation does not look to be much of a factor for the morning and evening commutes, but an area of rain in association with a low pressure system off to the west looks to move in for later Monday night through Tuesday. This first batch of rain looks to be quite minor, and more of a nuisance than anything. Temperatures for Monday night look to hover in the upper 30s to around 40 for most of the state, so frozen precipitation does not look to be a problem for this period. Heading through Tuesday rain will persist, with even more mild temperatures across the state, ranging from the low to mid 40s statewide.

If you're looking for snow and a wintry appeal for Christmas Eve and day, you are out of luck. A series of low-pressure systems will track off to the north and west of the state, keeping all of Connecticut safely out of the snow and cold. In fact, it will feel more like spring than winter on Wednesday and Thursday, with temperatures in the 50s throughout the area and even touching 60 degrees in the southern portion of the state. Along with the warmth, rain looks to be plentiful, with Christmas eve featuring some heavy rains for those of you who need to do some last minute shopping and preparations for the holiday. Localized flooding could be a concern, especially during the day on Wednesday. Rain looks to continue through Christmas day and taper off by Thursday night. As the storm system moves away, temperatures do not look to cool down very much with highs on Friday still in the mid 40s.

In the next 2 weeks, I do not see snow and cold being a big factor, but, models are hinting at there being a couple storms coming down the pipeline, one in the December 28th-29th range, and one right around New Years Eve. As of now, both storms do not have an abundance of cold to work with, but the right track could make things more white than wet, and as a result we are definitely keeping an eye on both potential storms. If they look to be realistic threats inside the 5-6 day window, we’ll go into more detail as always.

Today is Sunday, and without further adieu, the 7 day forecast:

Tonight: Mostly cloudy, snow showers ending before midnight, temps 28-32, chance of precip 40%

Monday: Mostly cloudy, some rain showers possible, especially late in the afternoon, temps 38-43, chance of precip 30%

Monday night: Cloudy with showers, temps mid 30s to around 40, chance of precip 40%

Tuesday: Cloudy with showers, temps low to mid 40s, chance of precip 50%

Tuesday night: Cloudy with rain likely, temps low to mid 40s, chance of precip 60%

Wednesday: Rain, heavy at times and mild, breezy, temps low to mid 50s inland, approaching 60 at the shore, chance of precip 80%

Wednesday night: Rain likely, mild, temps low to mid 50s, chance of precip 90%

Thursday: Rain in the morning, with scattered showers toward the afternoon, temps low to mid 50s, chance of precip 70%

Thursday night: Showers early then partial clearing, temps mid 30s, chance of precip 40%

Friday: Some clouds early then becoming mostly sunny, temps low to mid 40s, chance of precip 10%

Friday night: Mostly clear, temps low 30s, chance of precip 0%

Saturday:    Mostly sunny early, then some clouds with a chance of sprinkles in the afternoon, temps mid 40s, chance of precip 10%

Saturday night: Mostly cloudy, with a chance of sprinkles, temps mid 30s, chance of precip 10%

Sunday: *Watching closely* Mostly cloudy with steady showers moving in by mid morning, temps low to mid 40s, chance of precipitation 30%

Sunday night: * Watching closely* Cloudy with rain early, possibly changing to snow, temps low to mid 30s, chance of precipitation 30%

Have a good rest of your Sunday evening everyone! If you do need to head out tonight, please be careful as there could be some slick spots. As always, thank you for reading. Stay tuned!- Tim

Good evening from Southern Connecticut Weather!

Today was a mostly cloudy ,cool, and breezy day across the state, but we did manage to stay dry. Currently we already have quite cool conditions across Connecticut with temps ranging from the mid and upper 20s inland, to low 30s at the shore, with mostly conditions statewide. As we head through the evening, dry conditions will persist and temperatures will drop into the low to mid 20s.

Looking ahead to the day tomorrow, clouds will hang around with maybe some peaks of sun, especially in the morning. During the daylight hours of Saturday, conditions look to be mostly dry with temperatures only getting as high as the mid to upper 30s. As we head through Saturday night into Sunday morning, we are a watching a disturbance that will be passing to the south of Connecticut. The area of precipitation does not look to get close enough the area to cause any problems, but there could be some scattered flurries and sprinkles in the area later Saturday night through Sunday morning. What we are watching for right now is there to be some development off to the east, which could bring in more of a measurable, but minor, snowfall to areas especially east of I91. Any precipitation should start to taper off by the early afternoon hours of Sunday. High temperatures for Sunday afternoon will be in the mid to upper 30s statewide. We will be monitoring models very closely this evening/ tomorrow morning and will make a decision on whether a snowfall forecast map should be made. Sunday evening into the pre dawn hours of Monday look to be mostly dry with temperatures in the mid to upper 30s.

For next week, the models paint an ugly pictures for snow lovers. There looks to be 2 rain makers in the works for Monday into Tuesday and then again on Christmas Eve. Right now the stronger system looks to be the Christmas Eve rain storm, with a low pressure area tracking into the Great Lakes and secondary development looking to occur south and east of Long Island, gusty winds and heavy downpours with mild conditions look to be quite probable for Wednesday morning, afternoon, and evening. We will have more about the 2 systems in a discussion on Sunday evening when the extended forecast is released.

Have a good evening everyone! Look for a snowfall map/discussion (if needed) sometime tomorrow late morning or afternoon, with a more in depth discussion on the pre holiday rains and extended forecast coming sometime later Sunday night. As always, thank you for continuing to read and support Southern Connecticut Weather, stay tuned!- Tim

A good Wednesday evening to you from Southern Connecticut Weather!

Couple of things on the agenda tonight, starting off with a quick explanation of what changed on the models in the last couple of days to make the weekend snow threat all but vanish. Then, we’ll move to the extended day by day forecast, and finally, talk about a potential storm for Christmas eve and how it will help set up a much more wintry pattern in it’s wake.

First, the weekend storm(Or what was the weekend storm). At the time of our last post, models had fairly strong consensus on a coastal storm gathering in the gulf and coming up the coastline, bringing a round of precipitation and possible wintry weather to the region. However, over the last 36 hours or so, we’ve seen a strong trend in the models towards deamplifying this system, and as a result, a storm forecast to be sub 990 milibars will now struggle to break below the 1,000 barrier. As a result, the storm won’t have the energy to come up the coastline and pull in cold air, and as a result, we get nothing but some light rain and warmer temps.

Why is this happening? There are a few reasons, but by far the largest has been the trend for the next system, currently modeled to be Christmas eve, to move forward in time on modeling. This causes the pacific jet to become stronger, and when it smashes into the ridge in the west, it knocks it down as it enters the CONUS, and as a result the mechanism for amplification is not there. Previously, it was modeled to stay offshore long enough to allow the first storm to amplify, but now, it has sped up in time, and as a result, when the first storm is trying to come up the coast and amplify, it cannot do so.

Some weak waves of moisture may still reach us, but given the warm antecedent airmass, would expect mainly rain showers on the coastline with rain and/or snow showers inland. Minor accumulations may be possible inland, but nothing of any significance is expected with this event.  There is a low(~10%) probability that this trends back towards the original depiction, but for all intents and purposes, this event is done for anything more than a minor impact.

An aside for a second. This is exactly the reason why one shouldn’t be speaking in specifics or certainties when you’re 5+ days out, because all it takes is a small change on modeling to make a completely different scenario. It’s not that we don’t want to answer your questions on amounts and impacts from such a long lead-time, but that we can’t do so with any sort of reliable accuracy. Sure, sometimes a storm remains consistent on modeling for the entire period leading up to it, but more often than not, you see these sorts of changes and that’s why we don’t like to speak in specifics when the leadtime is more than a few days.

Now, onto the daily forecast.

We’ll see generally calm and quiet weather for the first half of the period, before things get more active towards the end of the forecast. Let’s break it down day by day, interjecting with some commentary as needed.

Tomorrow: A chance of morning snow/rain showers, otherwise, partly sunny, with highs in the lower 40s, except in the NW hills, where highs will be in the mid 30s. Chance of precipitation is 40%

Modeling swings an upper level disturbance over the region tonight, but it’s lacking any moisture for more than a few snow/rain showers. An isolated dusting to an inch is possible in the higher terrain, but the most likely result for any area is nothing.

Friday: Sunny, with highs in the mid 30s.

Saturday: Sunny, clouds build later, highs in the mid to upper 30s.

Sunday: A chance of rain and/or snow showers, with primarily rain showers on the coastline and a higher chance of snow showers inland. Otherwise, cloudy, with highs in the mid to upper 30s. Chance of precipitation is 50%.

Monday: Cloudy, with highs in the low to mid 40s.

Now, this is where the simple forecast gets a little more exciting. Models are in pretty strong agreement that we’ll see a very strong system coming out of the south on Tuesday, but where it goes is still up for debate. The ECMWF and it’s ensembles track the system almost due north, and by Christmas morning, have tracked it basically on a straight line through the Midwest and into the Great Lakes, where it’s gotten down to an impressive 962 milibars on the operational run!

Here’s images of the 12z EURO at hours 168 and 192, showing the positioning of the storm Wednesday and Thursday mornings.

The GFS, after agreeing with the EURO for the last few days, has started to trend east today, with it’s latest 18z run now making the system an apps runner as it runs up the Appalachians into eastern PA. Here’s images from the GFS valid for the same time as the EURO, showing the differences in placement. On the GFS, at the same time the EURO had the low over Ohio, the low is over eastern PA. Pretty big difference!

Finally, we have the Canadian model, which turns the storm into a coastal storm and tracks it into the Gulf of Maine. As of now, we don’t buy that solution, as it has no ensemble support and is an outlier.

All three of these solutions would have the same sensible impacts for most of the storm, that is, heavy rains and strong winds, but the GFS solution would likely lend it’s self to backend snows/snow showers as the low passes over us and lingering precip is left behind as the area moves into the cold sector. As a result, will paint a 50% chance of rain in the forecast for Tuesday, a 70% chance of rain in the forecast for Wednesday, and a 50% chance of rain or snow for Christmas day.  Temps will be above normal for Tuesday and Wednesday before crashing to below normal on Christmas day.

While this storm is a Grinch storm for anyone looking for a white Christmas, it serves a fundamental role in reshuffling the pattern to bring us a much better window for wintry threats in it’s wake. The strong storm slamming into the PV to the north causes the PV to weaken, and as a result, leads to above normal heights at high latitudes and flips the NAO, EPO, and AO(The three regions of high level blocking) negative, meaning that above normal high latitude blocking is present. This weakening of the PV allows for a rush of cold air to funnel into the country, setting the stage for a return to a much colder pattern sometime between just after Christmas and the beginning of 2015 depending on which model projection you believe. Furthermore, the development of high latitude blocking promotes a positive storm track for coastal storms, and given that the STJ looks to continue to be active, there are plenty of reasons to be optimistic for the future if you’re a snow lover. It can find ways to rain/not snow in a good pattern, so don’t lock anything yet, but I’d think we’re in a good position for a flip to more wintry weather in the period between Christmas and New Years, with that regime lasting into at least early January and possibly beyond. This doesn’t guarantee a storm by any means, but it’s certainly a good look for one if you’re looking for snow…

Here’s an image of 500mb at hour 240 from the 18z GFS. Notice the strong positive height anomalies in the northern tier, suggesting a weak PV and negative values of the teleconnectors mentioned earlier. In future discussions, we’ll go into more detail about how to interpret these 500mb images, but for now, know that it’s a really nice look for a wintry pattern to develop.

That about does it for this discussion, so until next time, have a great night and thanks for reading! Next update either tomorrow or Friday. -SA