Winter Weather Archives - Page 7 of 20 - New York Metro Weather

Light wintry mix possible tomorrow, dreary weekend ahead

December 12, 2018/0 Comments/by Steven Copertino

Good afternoon!

The cool and quiet conditions that have been with us for the past week or so continue over the Northeast this afternoon, with the only real changes being that cloudiness has increased in earnest and highs today are only slightly warmer than the previous couple of days. Despite temperatures running a few degrees above what they have been, we’re still seeing highs across the New York metro area in the upper 30’s to lower 40’s, with lower to middle 40’s over portions of Southern New Jersey. Conditions should stay rather cloudy this evening and overnight as a shortwave trough over portions of the Great Lakes continues to head to the east, dragging up warmer mid-level air from the south. Temperatures this evening should remain cool, but not nearly as cold as the past few nights thanks to the increased low/mid-level clouds limiting any potential for radiational cooling. Expect lows to generally stay in the upper 20’s to lower 30’s for most of the New York City area-with middle to upper 20’s well to the NW and middle to upper 30’s over portions of SNJ.

Weekly Planner for the next 7-days

Light wintry mix possible tomorrow morning/afternoon

During our previous update we introduced the possibility of a period of light snow/rain moving through the Northeast on Thursday, and since that time we have seen models become a bit more bullish on this event. The same shortwave moving through the Great Lakes this afternoon/evening will be over portions of PA/NY by early tomorrow morning, with light snow likely breaking out over Central Pennsylvania.

Though this shortwave is rather dry, it will be given small boost of moisture from relatively warm and moist air advecting into the Northeast. This should allow the small area of snow to sustain itself during its journey through Pennsylvania tomorrow morning, possibly reaching New Jersey by 7-9am. Once we get to around 10-11am, we should see precipitation expand into New York City and portions of Long Island. Given the limited dynamics/moisture available with this system in addition to very marginal surface temperatures, this system will not be an areawide snow producer. As of right now, it looks like locations mainly to the north of Trenton, New Jersey to NYC should begin as snow, but the same warm air advection that will be causing the precipitation will also help to gradually change precip over to light rain or a wintry mix from south to north.

Locations to the north and west of the immediate New York City area should have the best shot at staying mainly light snow for most of the morning/early afternoon, in addition to locations with greater elevations. While snow will likely be in the air tomorrow, the vast majority of the area should see issues with the snow sticking, outside of colder surfaces given the very marginal airmass. Additionally, snow growth a few thousand feet above the surface will be far less than ideal, meaning that snowflakes could be very small and malformed. This only further complicates any accumulation talk, but at this time a general coating to two inches is expected from Pennsylvania and into portions of NNJ/SNY (with the potential for locally higher amounts for elevated locations).

The timing of the precipitation ending will be highly dependent on when the shortwave outruns the best WAA (warm air advection), but this looks to be during the late afternoon hours. Any remaining precip during the late afternoon hours should change to a light wintry mix for the remainder of the area. All in all, this should not be a highly impactful system, but it could cause some slick road conditions, so please use caution when traveling tomorrow.

Loop of this afternoons NAM model showing the light snow/mix event for tomorrow morning and afternoon. Note how most locations around New York City end as rain.

Weekend storm likely to deliver wet and dreary conditions through Sunday

Back on Monday we mentioned the potential for heavy rain from an approaching upper level low over portions of the Southeast, however since that time the reliable computer models have trended weaker/more disjointed with this system as a whole. The result of a weaker system for the Northeast means that the strong low level jet that was forecast to occur over the East coast is now much less likely which severely limits the heavy rain/wind threat.

While we will likely see moderate to possibly locally heavy rain move into the area by Friday night and into Saturday morning, the risk for widespread heavy rain and potential flooding is now much lower. As the upper level low exits the coast on Sunday there will be the chance for some additional rainfall, especially along the coast. Interestingly enough, some models develop a coastal storm late Sunday and into Monday that could potentially extend the wet/unstable period a bit longer, but this remains quite uncertain at this time. We will continue to monitor the progress of this system as more details become clear in subsequent updates.

This afternoons ECMWF model showing a weaker/disjointed low level jet over portions of the East Coast early Saturday morning

We will have further updates on tomorrow light mix event and this weekends rain event by tomorrow!

Have a great evening!

Steve Copertino

Snow passes to the south Sunday, cold and calm next week

December 7, 2018/1 Comment/by Steven Copertino

Good afternoon!

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Things have once again turned quite calm over much of the Northeast today after a weak upper level disturbance moved through last night and produced some light snow well to the north and west of the New York City metro. Strong northwesterly flow behind this system has cleared out remaining moisture in the atmosphere and has replaced it with cold, dry Arctic air. Despite the cold mid level temperatures, clear skies have allowed for temperatures to rise into the middle to upper 30’s over much of the Northeast, with lower 40’s showing up in the city and portions of southern New Jersey.

The remainder of this afternoon will feature much of the same, with mostly sunny skies and light winds. There may be a chance at some more isolated snow showers if you’re traveling to eastern Pennsylvania and southern New York, but these should be quite tame. As we head into the evening hours and overnight, yet another Arctic shortwave will be passing to our north, which will provide a fresh injection of very dry and very cold air. Additionally, an area of high pressure will be edging it’s way into the Ohio Valley and Northeast. Given the dry air, fresh cold mid to upper level, and light winds, we fully expect radiational cooling conditions to be near-ideal tonight. This should allow overnight lows to drop well into the 20’s and teens over much of the Northeast, with even some single-digit readings possible. If you’re heading out tonight, definitely bring a heavy coast as it will feel more like January than December!

This afternoon’s ECMWF model showing surface temperatures 12-20 degrees below normal Saturday morning (AccuWx Pro)

Snowstorm passes well to the south later this weekend

Weekend Weather Rating | 8/10

As we talked about back on Wednesday and earlier this week, the storm we have been watching for the better part of the last ten days now appears to slide well to the south of the Northeast during the day on Sunday and into Monday. The models have trended even stronger with the confluence over eastern Canada over the past couple of cycles, which has caused an even greater shift to the south.

It now appears that places like Washington DC are unlikely to see any meaningful precipitation from this storm, while locations in southern Virginia and North Carolina may face a very impactful winter storm, with substantial snowfall and dangerous ice accretion. As of this update, the National Weather Service is forecasting snowfall totals of up to 12-18″, with locations in the mountains of NC likely to see over two feet of snow by Monday. Those who live in this region should be prepared to have normal operations and routines severely disrupted at least through Monday night-if not longer.

Back up north in our neck of the woods, Sunday should remain cold and clear, with a chance of increasing clouds towards sunset. Both Saturday and Sunday should feature highs in the middle to upper 30’s, with lows well into the 20’s. Locations well to the north and west should even be able to dip back down into the teens Saturday night.

Loop of this afternoons 3km NAM model showing the significant winter storm passing well to the south of the region this weekend.

Loop of this afternoons 3km NAM model showing the significant storm passing well to the south of the region this weekend. Heavy snow will be likely for portions of the Mid-Atlantic and Southeast

Quiet conditions and below normal temps persist into next weekend

After this weekend’s storm exits off the Southeast coast Monday night, we should see very quiet and cool conditions for the majority of the next week. Temperatures will likely remain 5-15 degrees below normal along the east through Wednesday, with lows sticking well-below freezing for the Northeast.

However, by the time we get to around Wednesday/Thursday, a large and energetic upper level disturbance will be moving into the Rocky Mountains. This upper level disturbance could be our next shot at some precipitation by the time we get to next weekend. At this time the models are showing an area of low pressure developing over the Midwest, which would bring a significant amount of moisture and warmer air up through the southern states and eventually into the Northeast. This would likely result in an increased chance for rain for the NYC area next weekend, but we’ll certainly be keeping an eye on this potential system during the course of next week.

500mb height anomalies from this afternoons ECMWF model showing an unusually deep closed upper level low over the south, with an area of ridging over the East.

Have a great weekend!

Steven Copertino

Unseasonably cold and dry conditions prevail, update on the snow threat this weekend

December 5, 2018/1 Comment/by Steven Copertino

Good evening!

Today was quite the interesting day across the tri-state area as the area of low pressure that we have been talking about for the past few days developed off of the New Jersey coast early this morning. This area of low pressure was spawned by a mid-level disturbance that was able to organize just at the last second as it approached the Mid-Atlantic coast. As both the surface low and the mid-level system both organized this morning, a narrow area of snow broke out over portions of southern New Jersey. This area of snow quickly grew from east to west during the early afternoon hours, extending back into eastern Pennsylvania at its peak. The small, but impressive band of snow virtually stalled over Atlantic county and produced snowfall rates of up to 1.5″ an hour. At the time of this article the highest snowfall totals from southern New Jersey are in the 4-6″ range, but it would not be surprising at all to see a few isolated reports come in higher. Elsewhere, there was a rather steep gradient with accumulations mainly in the 1-3″ range to the north and south of the main axis of heavy snow.

This area of low pressure and the associated surface trough are now beginning to pull to the east, causing any residual snow along the coast to wind down. We should see this low continue off the coast this evening, with calm and decreasingly cloudy conditions through the overnight hours for the vast majority of the Northeast. Usually a storm pulling away from the coast would produce near-ideal conditions for radionatal cooling all the way to the coast, but there appears to be a chance that stubborn mid/upper level clouds will hang on just enough, at least for the immediate New York City area. Accordingly, lows will likely stay in the middle to upper 20’s tonight, with middle to lower 20’s likely for locations to the north and west.

Latest high resolution water vapor imagery, surface temperatures, surface winds, and regional radar showing the area of low pressure responsible for the NJ snow beginning to head east

Unseasonably cold and dry conditions to continue through the weekend

Thursday morning should start off like every other morning so far this week, with mostly sunny conditions and cold temperatures in the middle to upper 20’s for the AM commute. Clear and cold conditions should continue through the afternoon hours before a broad area of upper level energy approaches the region from the northwest. While this system should remain relatively dry given the fact the associated airmass is continental arctic, there may be just enough lift to spark the development of light to moderate snow showers towards the evening hours tomorrow night. While the bulk of this activity should stay over portions of New York state and Pennsylvania, it would not be all that surprising to see some narrow bands extend all the way back into portions of New Jersey and possibly even NYC. Otherwise, increasing cloudiness will put a lid on low temperatures tomorrow night, with temperatures likely staying in the middle to upper 20’s for the majority of the tri-state area.

By the time we get to Friday morning, yet another shot of cold/dry air will quickly move through the Northeast, likely clearing out any residual clouds from the previous night. Temperatures should stay in the upper 20’s to lower 30’s during the day on Friday, but occasionally gusty winds may make conditions feel a good 10-15 degrees cooler. Winds will likely calm down during the afternoon hours on Friday as an area of high pressure begins to edge into the East. With high pressure in control and all levels of the atmosphere very dry, we should see excellent conditions for radiational cooling to occur. Lows on Friday night will be quite cold, with readings dropping well into the 20’s, with teens likely for portions of NW New Jersey and southern New York. All in all, temperatures over the next few days will range anywhere from 5-15 degrees below normal across the entire Northeast, which is much more like January as opposed to early December.

Loop of the 18z 3km NAM showing unseasonably cold conditions persisting throughout the next few days.

Late weekend storm likely to stay south of the NYC area

Over the past five days or so we have been watching numerous pieces of energy in the atmosphere located over the Arctic, the Pacific, and Alaska which will likely interact with one another by the time we get to Saturday afternoon over the Southern Plains. As these pieces interact, a large area of heavy rain and snow will gradually develop and begin to produce a swath of significant snow that could extend from Oklahoma to the Mid-Atlantic coast when all is said and done. While we do know that these various pieces for the storm will likely come together, what we don’t have nailed down yet is exactly how and when they will do so.

As of right now, the most likely scenario is that the main upper level system over Texas will begin to strengthen during the day on Saturday, while another piece of energy from the Arctic dives into the Northern Plains, causing the main storm to speed up. Additionally, another area of energy will likely be located over Southeastern Canada, which will be injecting very dry air over portions of the Mid-Atlantic and Northeast. This dry air will essentially act as a wall during the day on Sunday as the main surface low moves through the Southeastern US and tries to make some northward progress. At this point, the forecast will be dependent on just how strong the disturbance over Southeast Canada is at the time. If the system is weaker, there is a chance that meaningful precipitation is able to make its way north and impact DC to Philadelphia. However, the model runs from this afternoon showed increased dry air and “confluence”, forcing the main impacts down into portions of KY, WV, VA, and NC.

While there is still time left before Saturday, we feel that there will likely not be significant enough changes with the predicted upper air pattern to cause any major changes with this forecast for the NYC area.

In summary, it appears increasingly likely that the immediate NYC area will remain well to the north of any potential impacts, with only increasing clouds and cold temperatures during the day on Sunday.

Current states at highest risk for significant winter weather impacts: KY, NC, SC, VA, WV

Current states at risk for some impactful winter weather, with high uncertainty: MD, DE, PA, NJ

Current states with lowest risk for impactful winter weather: NH, VT, ME, MA, CT, NY, RI

51-member ensemble from the European model showing the probability of 3″ or greater of snow. At this time significant impacts from this system are quite low.

Make sure to check back in during the day tomorrow for more updates on this system!

Steve Copertino

Cold and clear start to December, watching this weekend’s storm potential

December 3, 2018/0 Comments/by Steven Copertino

Good evening!

After a dreary and foggy weekend, we started the December work week off with much improved conditions across much of the Northeast. A weak cold front associated with an area of low pressure over eastern Canada moved through the Northeast and Mid Atlantic states early this morning, which effectively cleared out any lingering moisture from this weekend. Despite having the weak cold front move through this morning, the cold air behind the front was lagging behind just enough to allow for relatively mild conditions along the I-95 corridor. With mostly sunny skies and a above-normal mid level temperatures, we saw highs reaching into the lower to middle 50’s across much the region, with locations well north and west of the city seeing highs in the middle 40’s. These temperatures were above-normal for this time of year, but this may be the last day with above-normal temperatures for some time.

A weak and strung-out area of upper level energy is currently moving through the Northeast and Mid Atlantic this evening, which has brought an increase in clouds, with some rain and snow showers being reported over portions of western and northern NY state. While increasing clouds are likely for the remainder of this evening and into the overnight hours, any chance of precip will remain well to our northwest. The increasing clouds will likely quash any chance we have at getting decent radiational cooling during the overnight hours, so expect overnight lows to stay generally in the middle to lower 30’s for much of our area. Lows in the upper to middle 20’s will be possible for locations well to the north and west of the NYC area.

Radar, WV satellite, and surface temperatures as of 5pm over the Northeast.

Tuesday through Thursday

The weak area of mid to upper level energy moving over the area will likely begin to kick out of the Northeast by 8am tomorrow, which should pave the way for a clear, but cold start to Tuesday morning with temps likely in the lower 30’s for much of the New York metro area. With northwesterly flow in place, colder air will move down from Canada which will only allow for a rather limited increase in temperatures over the Northeast. Highs will likely only reach the middle 30’s during the afternoon hours Tuesday, which will be slightly below-normal for early December. Clear conditions will continue throughout the evening and overnight hours, with lows reaching down below freezing all the way to the coast for the entire Northeast. While the city itself and locations closer to the coast should get down into the upper 20’s, lower to middle 20’s will be likely for portions of northeast NJ and southern NY.

Wednesday should start off as yet another clear but cold day with highs staying in the middle to upper 30’s. Another elongated and disorganized upper level system will approach our area during the afternoon hours from the west, which may bring an increase in cloudiness, especially over portions of the Mid Atlantic and southern New Jersey. As this disorganized upper level system approaches the coast later in the day on Wednesday, it may have a chance to strengthen just a bit while its centered over the Delmarva peninsula. While most of the model guidance has any organization of this feature occurring well offshore Wednesday evening, there is a chance that this system is able to spawn an area of light snow showers over parts of the Mid-Atlantic and portions of southern New Jersey. While there is a relatively low chance of this happening, the mid to upper level setup shown on the reliable model guidance is one that has been known to cause whats is known as an “inverted trough”. These are incredibly difficult to predict even just a day or two out, but we will continue to monitor this potential in subsequent updates.

By Thursday, we should see another reinforcement of slightly below-normal temperatures as an incoming shortwave trough moves to our north over southern Canada. Available moisture looks to be very limited with this shortwave, so we’ll likely stay dry and clear for the vast majority of the day on Thursday. However as we head into the evening and overnight hours, we may see an increase in clouds and possibly some snow showers to the north and west of the city as upper level energy from the incoming trough begins to work its way in.

This afternoons ECMWF model showing increased moisture and lift near the NJ coast later in the afternoon on Wednesday.

Watching for a Potential Storm along The East Coast Later This Weekend

Once we get to Friday, our attention will begin to turn our West where an upper level low will be moving in over southern California. This system has been on our radar for quite a few days now as almost all of the reliable model guidance has shown this system becoming an impactful snowstorm for portions of the South and East later this weekend.

While model guidance has been highlighting the potential for a snowstorm over various points during the past couple of days, the delicate nature of the upcoming pattern has really allowed for significant run-to-run changes of where exactly along the South and East has the best chance of seeing significant snow. Despite this afternoons operational models and ensembles showing the bulk of this potential system impacting locations south of the I-95 corridor and into portions KY, NC, SC, VA, WV, we did see some changes from previous runs that may support this threat inching to the north to some degree over the next couple of days. The final outcome will ultimately rely on exactly where and when key pieces of energy will drop into the CONUS and (possibly) interact with the main energy over the South in addition to the positioning of a crucial low pressure system near Greenland (the “50/50 low”).

As of right now the overall threat for an impactful snowstorm for the NYC area is low. It is important to note that we’re also six days out and confidence is also very low at this time. The low confidence in this forecast is not only due to model inconsistency but also due to the fact that we have seen this kind of scenario many times in the past where a system is forecast to stay well to south around a week out, only to trend more organized and further north as we draw closer. We will be keeping a very close eye on this system during the remainder of this week so make sure to check back for updates!

12z ECMWF showing the potential winter storm organizing over the Southeast on Sunday morning

Have a great night!

Steve Copertino

Archive for category: Winter Weather

Good afternoon!

Light wintry mix possible tomorrow morning/afternoon

Weekend storm likely to deliver wet and dreary conditions through Sunday