Conditions have improved substantially across much of the Northeast this Friday afternoon as a rather weak cold front cleared out any remaining cloudy & unsettled conditions.
Today has been a rather calm and seasonably cold day across much of the Northeast as a weak area of high pressure located to our north remains in control of our sensible weather. Spotty upper level clouds associated with a quick-moving shortwave trough moved through the southern portions of the area earlier this morning and into the afternoon hours, but quickly gave way to mostly sunny skies. Mostly clear skies and residual northwesterly flow aloft allowed highs this afternoon to stay in the upper 20’s to lower 30’s-with the vast majority of the region staying below freezing. High pressure to our north is expected to quickly move to the east through this evening and into the overnight hours. Surface flow will gradually begin to shift from the north/west, to a more southerly/southeasterly component during the overnight hours, which will help to increase cloudiness over the area. Overnight temperatures will likely be able to fall a few degrees, with readings likely staying in the lower to middle 20’s for the majority of the immediate NYC area.
~Updated Weekly Planner~
Our attention shifts to the Great Lakes region by tomorrow morning as an area of mixed precipitation along a cold front will be moving quickly to the east towards our area. The overall setup has become much less impressive since our last update, with only light snow accumulations expected well to the north and west of the immediate NYC area. Surface winds tomorrow morning will be out of the south and east, which will help to warm temperatures into the lower to middle 30’s all the way into NE NJ and SE CT. While precipitation may start off as a mix of light rain and snow for most of the area, a quick transition to a cold rain is expected for all locations outside of elevated portions of Northern New Jersey and the Lower Hudson Valley.
Precipitation will remain predominately light to occasionally moderate in nature into the evening hours before the front begins to move across the area. We may see an increase in precipitation rates as warmer air coming in from the coast interacts with the cold/dense incoming Arctic airmass off to our west. This could create a narrow band moderate snow that moves from west to east over the area, possibly producing a quick coating to an inch all the way down to the coast as temperatures quickly fall below freezing. Precipitation will quickly end from west to east during the very early morning hours of Wednesday with the main impacts from this system primarily being felt well off to the north and west of the NYC area.
Conditions behind the cold front will be quite blustery on Tuesday night, with wind gusts potentially getting into the 30-40 mph range as temperatures drop into the lower 20’s and upper teens. The rapidly falling temperatures and gusty winds will create the potential for any residual standing water to quickly freeze on untreated surfaces-possibly creating some hazardous travel conditions.
Our latest impact map for the light mix event tomorrow. The main impacts from this system will primarily be felt well off to the north and west of the city
The long-awaited “polar vortex” will be located just to the north of the Great Lakes by Wednesday morning, with very deep westerly flow overspreading the Northeast. The cold front associated with the weak surface low to our north will be exiting off the coast Wednesday morning just in time for the AM commute, allowing for gradually clearing skies. While the airmass behind this first front will be quite cold, the main Arctic front will wait until the afternoon hours of Wednesday to work its way into the NYC area. Southerly flow at the surface will overspread the NYC area ahead of the main Arctic cold front, allowing for temperatures to rise into the lower to middle 20’s Wednesday afternoon.
The aforementioned deep westerly flow directly associated with the strong tropospheric vortex to our west will cause mid level temperatures to plummet over the Northeast before surface temperatures have a chance to respond. This will create impressive “lapse rates” (change in temperature with height) Wednesday afternoon over the majority of our area. Furthermore, some weak mid level energy will be edging into portions of the Mid-Atlantic and Northeast during Wednesday afternoon. This setup will create the potential for some snow squalls to develop and quickly move from west to east around 12pm -4pm on Wednesday. Some of these squalls could be quite heavy in nature, producing very low visibilities at times and potentially dropping a quick coating to an inch for some locations. The Arctic front will finally blast through the NYC area during the late afternoon and early evening hours of Wednesday. Winds will quickly increase to around 20-30 mph, with gusts up to 40 mph as overnight low temperatures rapidly fall into the single digits across the entire forecast area–with temperatures likely falling below zero for elevated locations off to the north and west.
Thursday will be one of the coldest days of this winter season as highs struggle to make it out of the lower to middle teens for virtually the entire Northeast. Highs will be anywhere from 20-35 degrees below normal across the Northeast Thursday afternoon-which may wind up breaking a few records across the region. Wind chills will also be extremely cold, with readings likely anywhere from 10-20 degrees below zero by Thursday morning. Frigid and calm conditions will continue into the evening/overnight hours of Thursday, with lows in the single digits over the entire area.
Temperatures will moderate a bit on Friday, with highs likely getting back into the lower to middle 20’s, before a more significant warm up takes place later on this weekend.
ECMWF model showing surface temperatures anywhere from 24-36 degrees below normal on Thursday morning (AccuWx)
We’ll have an update on this Arctic airmass as well as a look at this weekend’s weather on Wednesday!
Have a great night!
-Steve Copertino
Today has been a brutally cold day across much of the East Coast as an impressive Arctic airmass blasted into the country on Sunday. Additionally, the messy storm system that affected the area this past weekend is now rapidly intensifying off to our northeast. This intensifying system is creating an impressive pressure gradient with the Arctic high pressure currently located over the Ohio Valley. The result has been strong, gusty winds of up to 40 mph creating wind chills anywhere from five to ten degrees below zero across the New York City area today. The extremely dry airmass in place has cleared out virtually any remaining clouds over the Northeast, which made for a classic frigid January day. High temperatures were only able to rise into the teens and single digits across the forecast area, with Central Park getting to around 14F, which is twenty-four degrees below normal!
Winds will gradually begin to diminish this evening as the area of low pressure off to our northeast begins to drift further away weakening the pressure gradient over the area. With clear skies and diminishing winds, radiational cooling will take over, causing temperatures to fall back down into the single digits for the immediate NYC area, and likely in the 0-5 degree range off to the north and west. Elevated locations of NW NJ and SNY may even drop back below zero tonight. Even with weaker winds, wind chills will likely still be 5-15 degrees below zero tonight, so definitely bundle up if you’re planning to head outside tonight!
Surface map from this evening showing the Arctic high pressure system moving through the Ohio Valley.
Tomorrow (Tuesday) will start off as another bitterly cold morning for the AM commute with temperatures in the teens and single digits for the immediate metro area. High pressure will likely be overhead at this time, so winds will be substantially weaker than the previous 24 hours. As the surface high and mid-level ridge passes overhead tomorrow afternoon, the cold northwesterly flow will be replaced with westerly and eventually southwesterly flow. This change in source region will allow temperatures to moderate a bit during the day. Highs will likely still be cold, with temperatures likely getting into the lower to middle 20’s for the majority of the NYC area. Mostly sunny skies and cold temperatures will last into the evening and overnight hours, making for a cold but pleasant day. Radiational cooling will once again take over Tuesday night, causing lows to drop back down into the teens and lower 20’s for the entire area, which is around 10 degrees below normal for late January.
Wednesday will be a day of transition as a large mid level trough moves into the Central United Sates. As this trough digs in an amplifies, a ridge will build over much of the East, allowing for much warmer temperatures to move in. A weak surface low will cut off to our west during the morning and afternoon hours on Wednesday, leading to a warm front passing through the Northeast. This warm front will aid in the development of some scattered showers during the day on Wednesday, with the potential for some light freezing rain during the onset for elevated locations well off to the north and west of the city. Once the warm front moves through, highs will likely rise into the upper 30’s to lower 40’s for the entire area, which will be 10-15 degrees above normal!
The aforementioned mid level trough will gradually shift east during the evening on Wednesday causing a deep area of moisture to begin to stream up through the Southeast and into the Northeast. The scattered light to moderate showers will eventually give way to more steady rain overnight and into Thursday morning. A wave of low pressure may try and develop along the frontal boundary draped over the Northeast, which could introduce a round of moderate to occasionally heavy rainfall during the morning and afternoon hours of Thursday. This frontal system will finally shift off to our east Thursday evening, bringing an end to the precipitation from west to east. Highs on Thursday will be quite mild, with temperatures reaching into the middle 40’s before dropping back down into the 30’s by Thursday evening.
This evenings GFS model showing an impressive plume of moisture aimed at the Northeast on Thursday.
Temperatures look to drop back down to seasonable levels on Friday as a cold front moves through the Northeast. These seasonable temperatures are expected to last through this weekend, with the potential for some snow showers on Sunday as an energetic upper level system moves through the Great Lakes and into the Northeast.
There are some indications that we may have to monitor the East Coast next week for our next storm threat as an abundance of energy drops into a trough located over the Central United States. While we will likely still be lacking any kind of blocking for this time period, we are quickly approaching a time period that is traditionally favored for increased storminess across the east!
The ECMWF model showing a period of increased troughiness across the eastern half of the country (courtesy of Tomer Burg)
Thanks for reading and we’ll have an update on Wednesday!
-Steve Copertino
Today has been a rather gloomy and cold January day across much of the Northeast as the weak system that dropped some light snow across portions of the metro area this morning continues to quickly head offshore. As discussed in previous updates, this system was likely to only produce a trace to one inch of snow over the area, and that is exactly what has been reported as of this afternoon.
As the snow departed late this morning, mainly cloudy conditions remained overhead with mid level flow increasing out of the southwest. These southwesterly winds have allowed for a slightly more marginal airmass to overspread the area today. Coupled with the persistent cloudy conditions, this caused highs today to rise into the middle to upper 30’s across much of the forecast area-with 40’s reported closer to the coast. Cloudy and slightly above-normal temperatures will continue into the evening hours before a mid level disturbance passes well to our north. This system will be accompanied by a cold front that should help to clear out some of the remaining clouds tonight and usher in colder temperatures from our northwest.
Lows will likely drop back down into the lower to middle 20’s for the majority of the area this evening, which will be right around normal for this time of year.
This evenings high resolution NAM model showing lows backing down into the 20’s and lower 30’s for the NYC area
While tomorrow (Saturday) will likely start off quite calm and clear, the winter storm we have been talking about for nearly ten days now will be quickly approaching from the west. By 8 am, the storm will be centered over the Tennessee valley, with moderate to heavy snow expanding into much of the Ohio Valley. While the main shortwave trough associated with this system will not be able to completely interact or phase with the larger system over Canada, it does appear that there will be just enough of an interaction to keep the bulk of the heavy snow well off to the north and west of the immediate NYC area.
As we head into Saturday afternoon, the surface low over the Tennessee valley will be picking up steam and intensifying. As it does so, a large area of warm/moist air will begin to stream northward over much of the Southeastern states. All of this warm and moist air just above the surface will collide with a strong Arctic high pressure system over southern Canada and cause a moderate to heavy band of snow to develop over portions of New York and Pennsylvania. Light snow will likely begin to move into portions of Eastern New Jersey by 3-4 pm, with the snow quickly picking up in intensity over time. This band will continue to head east by 4-5 pm, likely overspreading the entire metro area by that time. All of the warm/moist air moving into the Northeast and colliding with colder air to the north will cause an enhanced area of lift within this band of snow, which could push snowfall rates into the 1-2″ per hour range–especially over portions of EPA, SNY, and NW NJ.
This area of moderate to occasionally heavy snow will likely continue into the evening hours of Saturday. It is at this time that precipitation types will start to become an issue. Due to the SW to NE orientation of this system thanks to the modest interaction with the system located over Canada, warmer air in the lower levels of the atmosphere will begin to overspread much of Southern and Central New Jersey, and eventually into the immediate NYC area. While the overall track of this system and the actual degree of interaction with the aforementioned Canadian system will determine the timing of this changeover, much of the metro area will likely see a change to a mix of sleet, freezing rain, and plain rain by 11 pm to 1 am. Locations off to the north and west of the immediate NYC area could potentially hold onto pure snow few a few more hours, causing a steep snowfall gradient to develop over our area.
Warm/moist air will continue to push further north into the forecast area overnight on Saturday and into the early morning hours of Sunday. Locations around the immediate New York City area have a good chance to flip to all rain at this time, with locations to the north and west potentially changing over to a dangerous mix of sleet and freeing rain. In fact, the freezing rain threat will be quite high over this area, with up to a tenth to a quarter of an inch of freezing rain possibly falling by Sunday morning.
The combination of moderate to heavy snow and freezing rain will likely cause very significant travel disruptions north and west of the city on Sunday morning.
Our latest total snowfall accumulation map for Saturday and into Sunday morning. The hatched area denotes the potential for significant freezing rain and sleet accumulations.
Dangerous Flash Freeze Possible Sunday and into Monday
Precipitation will likely still be ongoing by 8 am Sunday morning, with rain mostly expected for the vast majority of the forecast area as the surface low pressure system will likely be over Southern New Jersey at this time. Despite the change to plain rain, much colder air will be quickly approaching the area as the surface low begins to pull to our east during the afternoon hours on Sunday. Temperatures will quickly fall well-below freezing and into the lower to middle 20’s from west to east, likely causing any standing water to refreeze. Any residual precipitation over the area will need to monitored, as a flip to snow would be possible.
Regardless, true Arctic air will work blast through the entire forecast area by Sunday night, with lows dropping down into the single-digits! Winds will also be quite strong behind this system, with gusts up to 35 mph possible. If significant ice accumulations do occur over portions of the area, then there could be an enhanced threat of power outages Sunday night.
The colder than normal weather pattern is very likely to remain in place into next week, as a piece of the polar vortex fractures and settles in to the north of the region. This will keep cold and potentially active weather in the forecast as we move toward the back half of the week, and especially into next weekend.
We will Continue to provide updates on this storm over the next day or so. Please stay tuned to our social media accounts for up to the minute information!
Thanks for reading!
-Steven Copertino/John Homenuk