Category Archives: Storms

NYC Blizzard Update – Mar 13, 2017

March 13, 2017Noreaster, NYC, Snow, Storms, Weather Updateblizzard, coastal low, heavy snow, low pressure, new york city blizzard, new york city snowstorm, new york city weather, new york city wx, noreaster, nyc weather, nyc wx, snow, snowstorm, stella, winter storm, winter storm stellaLei Zhao

Classic major nor’easter to bring blizzard conditions to a large swath of the Northeast Tuesday just days from the official start of spring. Areas in and around NYC likely to see snowfall accumulations of over 1 foot, locally higher. This may end up being one of the biggest snowstorms/blizzards in history for the month of March in NYC.

Rest of today – the proverbial calm before the storm. Mostly sunny, cold, with high temperatures in the low-30s.

Tuesday – a major late season nor’easter will bring heavy snow and blizzard conditions to the area. Blizzard warning in effect for the entirety of Tuesday. Snow starts falling overnight into Tuesday. Heaviest snows forecast to begin around the morning rush and continue through most of the day. Blizzard conditions expected on the coast with steady north to northeast winds 30-35mph and gusts over 45mph. Visibility near zero at times. High temperatures at or below freezing. Widespread accumulations over 1 foot and approaching or exceeding 18″ expected around the NYC metro area. Details on the storm at the end of this post.

Wednesday – lingering chance for snow showers early with wrap around moisture on the backside of the departing nor’easter. Mostly cloudy with a high near freezing.

Thursday – skies clearing, high temperatures in the low-mid 30s.

Major Blizzard to Impact the NYC Region

Winter Storm Stella, as the Weather Channel refers to it, is set to bring widespread heavy snow to the area beginning overnight Monday and continuing throughout the day Tuesday.

Impacts – Snow accumulations over 1 foot, in many cases approaching 18″. Locally higher amounts, with some areas possibly approaching 2 feet. Heavy snow and blowing snow during the day Tuesday. Snowfall rates 2-4″ per hour and possibly higher in the heaviest snow bands possible. Thundersnow may accompany the strongest snow bands. Blowing and drifting snow with steady northeast winds 30-35mph and gusts 45-50mph will contribute to blizzard conditions with near zero visibility at times. East and northeast facing shorelines may experience moderate coastal flooding during high tide cycles. Heavy, wet snow at the coast combined with high winds may lead to power outages. Hazardous travel conditions, severe disruptions to aviation likely. High confidence in storm total snowfall at this point, but there is still uncertainty about whether and where mixing could occur.

Timing – Snow begins early in the overnight hours Tuesday. Light accumulations of 2-4″ possible by daybreak. Heavy snow likely beginning during the morning rush hour and continuing through most of the work day, as well as into the evening rush hour. Winds quickly intensifying from the morning and staying steady through the evening hours. Heaviest snow tapers off in the early evening hours, but snow showers could continue overnight. Winds remain strong overnight into Wednesday. Conditions improve going into the morning Wednesday.

Discussion – an area of low pressure that had its origins in the Pacific has made its way across the northern US, impacting the Northern Plains and Upper Midwest with snow. This storm system will phase with a secondary, coastal low pressure system that is currently moving up the coast from the Southeast. As these storms merge, the coastal low will undergo rapid intensification and cyclogenesis, becoming a strong Nor’easter. This storm will be drawing on subtropical moisture, and will encounter an airmass that will be quite cold due to the presence of an Arctic high pressure system prior to the storm’s passage. These ingredients will set the stage for a classic major blizzard for the Northeast late in the winter season, only days from spring.

As always, uncertainty remains about the exact location of the heaviest snow bands with this storm. Areas that are impacted by these bands can easily rack up several more inches than surrounding areas that are spared. The storm is expected to track west of the 40°N/70°W benchmark. However, during the last model runs, the storm track has trended north and west, increasing the chances for the city itself to see the heaviest snow, in addition to areas north and west. If this track shifts west some more, warmer air off the ocean wrapping into the core of the storm from the south could induce mixed precipitation with rain cutting down on totals in the city and Long Island. If the track shifts east, heavier snow would fall over points east of the city.

NYC Weekend Weather – Mar 09, 2017

March 9, 2017NYC, Snow, Storms, Weather Update, Weekendcold front, new york city weather, new york city weekend weather, new york city wx, nyc weather, nyc weekend weather, nyc weekend wx, nyc wx, polar vortex, rain, snow, snowstorm, weatherLei Zhao

Above average temperatures today give way to accumulating snow Friday. Very cold air then rushes in for the weekend, much along the lines of last weekend. This time around, cold air will persist, as a polar vortex is set to take hold of the East Coast. With this cold air in place, there is potential for a significant snowstorm in the form of a Nor’easter/coastal storm early to mid-week next week.

Rest of today – quite warm still with high temperatures remaining steady around the mid-50s. Breezy with west wind between 15-20mph under clear skies. Increasing clouds towards nightfall.

Friday – a rain/snow mix is anticipated to begin falling overnight, steadily transitioning to all snow by daybreak. This looks to be a messy commute. A cold front slides south of the area and a strengthening low pressure center moves along this frontal boundary, bringing us this snow. Due to warm temperatures in preceding days, snow will have a hard time sticking at first, but temperatures will remain cold enough throughout this event to yield likely snow accumulations of 3-5″.

Saturday – temperatures will remain well below normal as winds shift to the northwest following the passage of the cold front and storm system above. Breezy with winds around 15-20mph and decreasing clouds. High temperatures will struggle to hit freezing. Overnight lows leading into Saturday and then overnight into Sunday only in the teens.

Sunday – cold, sunny, with high temperature again barely at or above freezing. Spring forward occurs early Sunday, set your clocks ahead and get ready for more sunshine late in the day (not that it’ll help make things warmer right now).

Winter Not Giving Up – Possible Snowstorm Next Week

The predominant weather pattern thus far this winter has been one in which the jet stream has taken on an orientation that favors above average warmth over the eastern half of the US. Just as we turn the corner towards spring, it appears we are about to get slammed with a polar vortex and weather pattern more typical of February. While the cold itself will be enough to put a damper on spring, the real headline is the possibility for a significant late-season snowstorm in the form of a Nor’easter some time early to mid-week next week. Will keep you all updated on this as more data becomes available in the coming days.

NYC Weekend Weather – Feb 10, 2017

February 10, 2017NYC, Rain, Snow, Storms, Weather Update, Weekendblizzard, new york city weather, new york city weekend weather, new york city wx, niko, nyc weather, nyc weekend weather, nyc weekend wx, rain, snow, snow storm, snowstormLei Zhao

An eventful week of weather continues into the weekend, though not to the same degree of intensity. We will see another chance for snow, as well as rain this weekend. Temperatures rebound back to around or slightly above normal for the weekend. Looking ahead, there are some signals at another possible strong storm a couple weeks out, but it’s much to early to be certain.

Rest of today – cold, windy, sunny with areas of blowing snow. High temperatures below normal around 30ºF. Wind chills in the teens. Overnight tonight, we could pick up a light coating of fresh snow from a fast moving, and relatively weak storm system.

Below are some reported snowfall totals from yesterday’s coastal storm. As you’ll see, there was a fairly sharp cutoff between areas that received 9″ or more of snow. Long Island, Connecticut, and parts of the Hudson Valley got the largest totals. This was largely due to the fact that the most intense bands of heavy snow spent more time parked over these areas than it did in the city.

Saturday – conditions improving, along with warmer temperatures in the mid-40s under mostly cloudy skies.

Sunday – another storm system moves in from the Ohio Valley. This will bring a mixture of precipitation to the Northeast. Luckily, with high temperatures in the low-40s, we will see all rain.

Monday – winds pick up behind the departure of the storm system above, and skies should clear up as well. Temperatures should again be in the low-40s.

NYC Snowstorm Update – Feb 08, 2017

February 8, 2017Climate, NYC, Rain, Snow, Storms, Weather Updatecoastal low, coastal storm, cold front, heavy snow, high pressure, low pressure, new york city snowstorm, new york city weather, new york city wx, nyc snowstorm, nyc wx, snow, snowstorm, winter storm, winter storm warningLei Zhao

We’re in for a wild ride over the course of the next 24 hours as our weather goes from possibly record-breaking warmth to what is expected to be the most significant winter storm so far this season. Significant snow accumulations over 6″ and possibly as much as a foot are expected across the region, resulting in a winter storm warning for all of the NYC metro region.

Timing

Judging by the amount of sun we’re getting, temperatures will likely hit record-breaking levels in the low-60s in the city today. They will drop steadily to around 50ºF by the evening commute as a cold front pushes through and Arctic air flows in from the north. Overnight, temperatures will continue falling rapidly to around freezing. Precipitation is expected to begin around 3-4AM Thursday here in the city and continue through the early afternoon. Unfortunately, the timing of the heaviest precipitation does look to bring significant impacts to the morning commute.

North American High Resolution simulated radar 1km resolution, tomorrow at 8AM.

Impacts

Rain/snow mix to start, but by the morning rush, expecting all snow through the region. Heavy snow at times possibly reaching 1-2″/hr. Some thundersnow could occur. Hazardous travel conditions during the morning rush as plows will have trouble keeping roads clear with traffic and the moderate to heavy snow. Gusty winds could produce near-blizzard conditions with low visibility.

Snowfall Totals

Here are some graphics for snowfall totals from our local National Weather Service Forecast office. The general forecast calls for 6″-12″ in the city. The exact extent of totals will depend, as is generally the case with this type of storm, on where the heaviest snow bands set up and for how long they sit over an any given area.

Probabilities for 4″+ and 6″+ of snow respectively

Discussion

An shortwave that’s made its way rapidly across the country from the Pacific will move along the cold front that is pushing through today. As it does so, it will spawn a secondary low off the Mid-Atlantic that will strengthen rapidly as it moves over open water. At the same time, plenty of cold air will wrap around the deepening coastal low with high pressure to the west. This will put in place all the ingredients for a classic coastal winter storm for this area. The only thing keeping this storm from being a major blizzard with snowfall totals exceeding 2 feet is the fairly quick pace that it’s expected to move at.

This coastal storm will drive the expected heavy snows tomorrow. Its track is expected to take it just outside the 40ºN 70ºW benchmark, a spot that from a climatological perspective has translated to heavy snow storms for this region.

NYC Weather Update – Jan 23, 2017

January 23, 2017Flooding, Noreaster, NYC, Storms, Weather Updatecoastal flooding, coastal low, coastal storm, flooding, high pressure, high winds, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, weatherLei Zhao

Main weather headline to start the week will be a potent and slow-moving coastal storm bringing a variety of hazards to the region later today through tomorrow morning. This storm is the same one responsible for this weekend’s deadly tornado outbreak down south. Conditions improve dramatically towards mid-week.

Rest of today – a flood watch, coastal flood advisories, and high wind warning are in effect mostly through tomorrow morning. Cloudy with high temperatures steady around 40°F. Winds continue to increase throughout the day as a strengthening coastal low approaches and the pressure gradient between it and a high pressure center over Quebec tightens. A low-level jet will enhance winds. Sustained east and northeast winds of 30-40mph with gusts between 50-60mph will become commonplace late today and overnight. The strongest winds will occur closest to the coast.

Along with the strong winds, periods of heavy rain will bring the potential for 1-3″ of precipitation, which could lead to minor to moderate urban and small stream flooding. Timing of the onset of rain will be around 3pm this afternoon.

The persistent and strong northeast winds off the water will contribute to minor to moderate coastal flooding. This will be exacerbated during a couple of high tide cycles.

High resolution rapid refresh model simulated radar output for 3PM this afternoon

The storm approaching spans the better portion of the entire East Coast

Tuesday – rain and wind abate during the day, tapering off by the afternoon. High temperatures about the same as today in the low-40s.

Wednesday – as the coastal storm continues to pull away, temperatures rebound and mostly sunny skies return. High temperatures anticipated around 50ºF.

Thursday – another nice day with high temperatures in the upper-40s and mostly sunny skies.

NYC Nor’easter/Winter Storm Update – Jan 7, 2017

January 7, 2017Noreaster, NYC, Snow, Stormsnew york city weather, noreaster, nyc weather, nyc winter storm, snow, weather, winter stormLei Zhao

Overnight, forecast models shifted the track of the ongoing Nor’easter further west. This has implications for snowfall totals across the region.

Snowfall Totals

These have been bumped up for the city, which is now expected to receive 2-5″. The potential exists for more. Winter storm warnings now extend as far west as Nassau County, with points further east receiving as much as 7-12″.

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As always with Nor’easters, even as they are ongoing, considerable uncertainty remains a factor. With these storms, one or more banding features will develop and circulate around the center of the storm as it progresses northeast. The number, extent, intensity, and western limit of advancement of these banding features ultimately determines what areas get the most snow. Within these bands, snowfall rates could easily reach 1-2″/hour. West of the western limit of the progression of these bands, snowfall totals will drop precipitously, such that a distance of 10 miles could mean the difference between 2″ and 6″+.

Timing

You can already see the radar signatures of two bands of moderate to heavy snow spawned by this storm. One of these bands is currently pushing its way west through Long Island, while another progresses towards shore. Within these bands, travel conditions will rapidly deteriorate while accumulations rack up.

Looking ahead to this afternoon, it would appear that the heaviest snow will fall in the city around 2PM, or the early afternoon.

NYC Weekend Weather – Nov 18, 2016

November 18, 2016NYC, Rain, Storms, Weather Update, Weekendcold front, high pressure, low pressure, new york city weather, new york city weekend weather, new york city weekend wx, new york city wx, nyc weather, nyc weekend weather, nyc weekend wx, nyc wx, pressure gradientLei Zhao

An extended period of well above normal temperatures comes to an abrupt end this weekend as a strong cold front pushes through overnight Saturday into Sunday. On the back side of this frontal boundary, temperatures will average around 15ºF lower than we’ve seen this week. If you like it mild, go out and enjoy this weather before Saturday!

Rest of today – sunny and mild with high temperatures in the low-60s.

Saturday – another mild day on tap with lots of sun and a high around 60ºF. Chances for rain increase into the overnight hours, at this point peaking around midnight. Winds will pick up first from the southeast ahead of the cold front, then to the west. Sustained winds of 15-20mph with gusts over 30mph are possible.

Sunday – rain chances taper off but winds remain in the 20-30mph with strong gusts up to 40mph. High temperatures will be significantly colder than we’ve gotten used to and below normal in the mid-40s. A tight pressure gradient sets up between the departing low and a high pressure center to the southwest, blasting us with cold Canadian air as a result.

Monday – clouds diminishing gradually, winds still pretty breezy, and a high only in the low-40s.

NYC Weather Update – Nov 14, 2016

November 14, 2016Climate, Drought, NYC, Rain, Storms, Weather Updatecoastal low, drought, high pressure, low pressure, new york city weather, new york city wx, nyc weather, nyc wx, weatherLei Zhao

The beginning of the week will see much needed rain, and then transition to sunny and above average weather. Drought conditions have improved in New York State overall, though most of the improvement has been concentrated upstate.

Rest of today/overnight – rain begins to move in to the area overnight. Because of the very dry air that was in place to end the weekend, it will take some time before the moisture associated with a coastal low can saturate the air. It appears the most likely time for when heavier/steadier rains begin is around 4AM.

Tuesday – rain, moderate to heavy at times in the morning. Northeast winds around the coastal low responsible for the rain will keep temperatures cooler than normal in the low-50s with cloudy skies. Rain chances diminish substantially in the afternoon.

Wednesday – a small chance for lingering drizzle on Wednesday as temperatures rebound back into the upper-50s. Clouds will be on the decrease.

Thursday – sunny, with a high near 60ºF. High pressure takes over to to end the week.

Drought Improves Upstate, Still Severe in and Around NYC.

Recent rains have improved the drought situation for many portions of upstate New York, and also some areas of the city and Long Island. However, as you can see from the image below, much of the area is still gripped by severe drought.

NYC Weather + Hurricane Matthew Update – Oct 3, 2016

October 3, 2016Cool Images, NYC, Rain, Storms, Tropical/Hurricanes, Weather Update2016 atlantic hurricane season, cuba, haiti, hispaniola, hurricane matthew, new york city weather, new york city wx, nyc weather, nyc wx, tropical cyclones, tropical weather, weatherLei Zhao

After a gloomy, but appropriately fall-like start October, this week looks like it will bring much improved weather. Temperatures are expected to be just below or at normal for the majority of the week. The big question mark in the long-term for weather in our region is the progress of Hurricane Matthew, which could impact the area this coming weekend.

Tuesday – mostly cloudy to start with gradual clearing and high temperatures in the upper-60s.

Wednesday – mostly sunny with high temperatures in the upper-60s. High pressure anchored over southeastern Canada will give us an extended period of nice weather.

Thursday – sunny, warmer with high temperatures in the low-70s.

Friday – sunny, with high temperatures in the low-70s.

Hurricane Matthew an Increasing Threat to the US East Coast

goes20452016277uwlwk7 — Hurricane Matthew as captured by one of NOAA’s geostationary satellites on Monday, Oct 3 at 5PM EDT.

Hurricane Matthew poses an imminent and possibly catastrophic threat to Haiti, and portions of Eastern Cuba. Heavy rains from rain bands associated with the storm have already begun falling over Hispaniola and have hit Jamaica as well. Matthew is a potent Category 4 storm with maximum sustained winds at 140mph. It is expected to bring rainfall of 8-20″ across the region, with some places receive 7-11′ of storm surge.

Matthew has displayed a number of anomalous characteristics that have defied forecasters and experts best efforts at predicting its intensity. Matthew underwent a period of rapid intensification, going from tropical storm to a Category 5 hurricane with 160mph winds in just under 36 hours. This puts Matthew in an exclusive circle of just a handful of storms in recorded history that have accomplished this feat. Even more amazing, Matthew underwent this rapid intensification in the face of strong southwesterly wind shear that would typically stall a storm’s growth or weaken it.

During much of its life, a large area of intense thunderstorms has accompanied Matthew, at times exceeding the actual storm center in size. Scientists are uncertain as yet what role this feature had in Matthew’s unusual intensification. This feature has been impacting Hispaniola.

ganimwwcifn15 — Infrared satellite image of Hurricane Matthew as a strong Category 4, note the impressive area of intense thunderstorms east of the storm’s core.

Outlook for Hurricane Matthew

Matthew is expected to either skirt the extreme southwest peninsula of Haiti or make landfall there, then perhaps a secondary landfall on Eastern Cuba. The more interaction Matthew’s circulation has with the high terrain of these regions, the weaker it will get before entering the wide open, and warm waters of the Bahamas. It is expected to maintain major hurricane status (maximum sustained winds greater than 115mph) throughout most of the 4-5 forecast period.

Since even earlier today, major forecast models have come into much better agreement about the path of Matthew in the longer term. The unfortunate news is that the models have settled on solutions that push Matthew further to the west than previous runs. This dramatically increases the chances of a landfall somewhere on the Southeastern US, with Florida also in the range of possible tracks. Should this scenario unfold, we would be spared from a direct landfall here, but would still receive a storm of considerable strength with strong winds and heavy rains possible.

NYC Weather Update – Sep 26, 2016

September 26, 2016Climate, Drought, Rain, Storms, Weather Updatedrought, low pressure, new york city weather, new york city wx, nyc weather, rain, retrograde low, weatherLei Zhao

Fall has arrived. Temperatures have cooled noticeably, even though technically, they are still in the above normal range. There will be a few chances for much needed rain during the week, overnight into Tuesday, then during an extended period in the second half of the week.

Rest of today – increasing clouds with high temperatures hovering in the low-70s.

Tuesday – overnight into Tuesday, we’re expecting a fairly robust cold front to push through with enough moisture to give some areas around 1″ of rain. This is some much needed precipitation as we’re far behind where we should be for this time of year and a moderate to severe drought continues to grip much of the area. Rain should taper off for the most part by the AM rush Tuesday, with some lingering showers possible. Ahead of the cold front actually passing through, wind flow turns to the south, allowing temperatures to rise into the upper-70s.

Wednesday – the cold front passing through Tuesday will be the spawn of a low pressure center that will stay relatively stationary over the upper Great Lakes, but by later Wednesday, this low pressure will begin to transfer energy to a new low that will form closer to the coast off of Virginia. This low will eventually lead to steady rain chances for the remainder of the week, starting with a small chance on Wednesday. High temperatures are expected to be in the mid-70s.

Thursday – this begins a stretch of unsettled weather as the low mentioned above meanders, and retrogrades (moves west) and inland from the coast. This low will become cutoff from any meaningful steering currents, which means it’ll stick around for a few days. High temperatures will be cooler Thursday around 70ºF with mostly cloudy skies and periods of rain.

Drought Not Likely to Dissipate

Below normal precipitation continues to be expected for the region, which is still gripped by moderate to severe drought, in particular on eastern Long Island.

LZ | Weather

Weather updates & posts for NYC region