Category Archives: Weekend

NYC Weather Update – Feb 24, 2015

February 24, 2015Climate, NYC, Rain, Snow, Storms, Weather Update, Weekendarctic, arctic air, arctic cold, cold, cold front, new york city weather, nyc weather, nyc wx, snow, winter, winter weather, winter weather nycLei Zhao

After that brief “warmup” during the weekend, we’re once again mired in Arctic cold air. This cold trend continues with a reinforcing shot of cold air as a cold front sweeps through Wednesday. Behind that, high pressure builds in over the area for the end of the week and into the weekend, ensuring another prolonged stretch of chilly, much below normal temperatures.

Wednesday – ahead of what will a dry cold front passing through, high temperatures may be able to climb to just about the freezing mark under mostly sunny skies.

Thursday – once the cold front moves offshore, an area of low pressure will strengthen, but remain well offshore of the area. However, precipitation may still make its way over the region, especially the far eastern areas. There’ll be a chance for snow flurries further west in the city. Temperatures will be back in the mid-20s again in the wake of that cold front.

Friday – clearing skies will be accompanied by stagnant cold temperatures with highs again in the mid-20s.

Saturday – as you’ll se below, a strong 1040mb area of high pressure will be parked over the Ohio Valley will be responsible for the sunny, but cold temperatures through at least Saturday night. Highs Saturday may approach 30ºF. Normal highs for this time of the year are closer to 40ºF.Looking Ahead

814temp.new — Climate Prediction Center’s 8-14 day temperature outlook for March 4th to March 10th, with our region in an area expected to experience below normal temperatures.

The beginning of next week looks to feature a fairly active pattern, with two storm systems passing through, one on Monday, and another on Wednesday. With the current track of the second storm, it looks like we are going to be on the south side of the low pressure center. This would allow for warmer air to wrap into the area. We could top 40ºF again, but the tradeoff will be a slushy, wet day maybe with some mixed precipitation to start. Once this second storm passes through, we return to cold temperatures once again.

NYC Weekend Weather – Feb 12, 2015

February 12, 2015NYC, Snow, Weather Update, Weekendarctic, cold, cold front, new york city weather, nyc weather, nyc wx, snow, snow showers, weather, wind chill, winter weatherLei Zhao

The main headline for the upcoming weekend and into next week will be the very cold airmass that will be spreading over the region, bringing with it what will likely be the coldest temperatures we’ve seen thus far this year. The coldest period over this stretch will be overnight Sunday into Monday, when low temperatures in the city could touch zero. If that does happen, it would be the first time the city has hit zero or below since January of 1994, according to National Weather Service records!

Friday – there will be a noticeable difference in daytime temperatures versus today. High temperatures are going to struggle to even hit the upper teens in the city, once the cold front responsible for the off and on flurries today passes through tonight. Overnight lows will again be in the low teens in the city, and colder in outlying suburbs.

Saturday – another clipper-type system will move quickly through the area on Saturday, setting off a period of snow showers that could end up dropping 1-2″ across the region. High temperatures will warm up slightly – if you can call a high near 30 a warm up! Overnight, winds will begin to pick up, with wind chills between -5ºF to -15ºF.

Sunday – a stiff northwest wind will pick up. The clipper system that passes Saturday will rapidly intensify as it moves over the Atlantic. This will set up an increasingly tight pressure gradient with a high pressure center over the Great Lakes. This setup will swing the door wide open for Arctic air to blast into the region. High temperatures Sunday will be in the mid-teens in the city, and overnight lows may be as cold as zero or just below zero. Regardless, the sustained northwest winds will yield wind chill values between -15ºF to -25ºF.

Monday, President’s Day – sunny skies, but that Arctic airmass will still be very much in control, with temperatures struggling to hit 20.

Tuesday – a return to temperatures near freezing again with an approaching low pressure system that will deliver our next chance at precipitation late Tuesday into Wednesday.

NYC Weather Update – Jan 28, 2015

January 28, 2015NYC, Rain, Snow, Storms, Weekendarctic air, arctic front, cold, nyc weather, nyc weekend weather, nyc wx, rain, snow, storms, weather, wind chillLei Zhao

On the heels of the nor’easter earlier this week, we get another chance at snow tomorrow night into Friday, albeit of a much lighter intensity. Things get downright frigid after that with low temperatures Friday night in the single digits in the city, and wind chills below zero! The cold locks in over the weekend before we get another chance at precipitation to start off next week, continuing what has been an active weather pattern.

Thursday – clouds increase from west to east, with high temperatures hovering just above freezing. Precipitation begins overnight, and may include some rain/snow mix at the coast (all snow inland), but with minimal accumulations.

We get clipped by a clipper system Thursday night into Friday, with both NAM and GFS models pointing to us being on the periphery of the heavier precipitation.

Friday – light flurries continue into the morning Friday before ending, skies clear quickly while temperatures begin nosediving from a high in the mid-30s during the morning hours to the upper teens by sunset. Winds also pick up from the north and northwest as the departing clipper system from above deepens and the pressure gradient increases between it and a high pressure center over the Midwest. The combination of the cold temperatures and winds will likely induce wind chills below zero, so bundle up before you go out there Friday night.

Saturday – the deep freeze continues, with high temperatures only in the low 20s Saturday despite plenty of sunshine.

Sunday – another day of decent conditions, with clouds increase, but still cold with highs in the upper 20s. Sunday night into Monday, we get another shot at precipitation, although it’s a bit too early to nail down the specifics of this upcoming storm (whether it’ll be rain/snow, rain, or just snow, and how much).

NYC Weekend Weather – Nor’easter Update – Jan 23, 2015

January 23, 2015Freezing Rain, Noreaster, NYC, Precipitation Type, Rain, Snow, Storms, Weather Update, Weekend40 70 benchmark, freezing rain, high pressure, low pressure, mixed precipitation, noreaster, nyc weather, nyc weekend weather, nyc weekend wx, nyc wx, rain, sleet, snow, weatherLei Zhao

The details are starting to come together for tomorrow’s Nor’easter. Over the past day, forecast models have been pointing to a faster moving system, such that the onset of precipitation is expected to begin overnight tonight, with the bulk of the precipitation ending by early afternoon tomorrow. This storm is expected to throw a little bit of everything our way tomorrow, making for a nasty day overall, with snow changing over to freezing rain or sleet, then perhaps a period of plain rain, followed by a possibility of a rain snow mix.

What to Expect

Snow, moderate to heavy at times, beginning overnight tonight. Winds picking up from southeast, then eventually moving to the northeast and north during the day Saturday. Snow transitioning to a period of possibly freezing rain or sleet during the morning hours, then a period of rain around midday and a possible rain/snow mix towards late afternoon before precipitation gradually tapers off later in the evening. High temperature right around or slightly above freezing.

Forecast Storm Track

Forecast models are in generally good agreement that the center of this Nor’easter will be passing just inside the 40ºN 70ºW benchmark sometime in the late afternoon Saturday (approx 4-5PM).

Without a high pressure center to the north supplying cold air to the area, this setup will allow for enough warm, moist air to circulate around the eastern side of the low pressure center to give us a mix of precipitation throughout the day. The extent to which snow can be sustained will be strongly dependent on dynamical cooling, and how quickly cold air can be pulled in on the western side of the low pressure center.

Storm track forecast from the Weather Prediction Center, with clusters indicating forecast positions of individual ensemble members.

Snowfall Forecast

As you can see below, the probability of more than 4″ of snow is quite low for coastal areas, especially Eastern Long Island, where mainly rain is forecast. The heaviest totals (no more than 5″, most likely) will be concentrated well north and east of NYC where temperatures are expected to be cold enough to sustain all snow for longer. Because the forward speed of the storm is now predicted to be faster, the chances of NYC getting any significant snowfall (even 2″) is considerably lower. Most of the city is in a swath of between 30-40% chance of getting more than 2″ of snow.

Probability of greater than 2" of snowfall — Probability of greater than 2″ of snowfall

Probability of greater than 4" of snowfall — Probability of greater than 4″ of snowfall

Ice Accumulation

The probability of us receiving a trace, but a measurable amount of ice from freezing rain is quite a bit higher than the probability of receiving snow, with most of the city in the 40-60% range.

Sunday – the storm will be long gone by Sunday, and we’re expecting to hit highs in the mid-upper 30s.

Monday – there is some potential for a round of all snow on Monday, but forecast models have not been in good consensus on how this will play out. A clipper system is expected to pass through, though it is unclear whether this system will spawn a secondary low offshore. In the latter case, we could see some significant snow, while if it’s just a clipper, we probably won’t see more than a couple inches.

NYC Weekend Weather – Jan 22, 2015 – Nor’easter Coming

January 22, 2015Freezing Rain, Noreaster, NYC, Rain, Snow, Weather Update, Weekend40 70 benchmark, freezing rain, low pressure, new york city weather, noreaster, nyc weather, nyc weekend weather, nyc weekend wx, nyc wx, rain, snow, winter, winter wx, wintry mixLei Zhao

All eyes turn towards the imminent Nor’easter that will be bringing significant winter weather impacts to the NYC metro region. Many variables remain unresolved that could affect the eventual outcome, but at this time, it looks like we’re in for a nasty combination of freezing rain, rain, and snow during the day Saturday. At present, forecasts call for somewhere between 2-4″ of snow in the city along with some ice accumulation. Precipitation should fall as all snow north and west of NYC, however, overall accumulation should be slightly less than in the city itself since the most intense precipitation will remain near coastal areas.

Friday – we get a pleasant, sunny, and slightly above average day with high temperatures in the mid-upper 30s.

Saturday – a tricky forecast for Saturday. What we know for sure, with different forecast models in relatively close agreement, is that an area of low pressure now forming over the Texas Gulf Coast will track over the Southeast, and then offshore of North Carolina by Friday night/early Saturday. Once the low moves offshore, it will rapidly intensify, and then track right on or very close to the 40ºN 70ºW benchmark by Saturday afternoon/early evening.

The uncertain part about this scenario has to do with the thermal profiles in place. With no high pressure over us or to the north pumping in cold Canadian air, the depth of cold (sub-freezing) air will be relatively shallow.

As the Nor’easter approaches us, the cyclonic flow around its center will wrap in some relatively warmer air in from the ocean and points south. This makes for a complicated picture – with warmer air aloft (see animation below) during parts of the day, and below freezing air nearer to the surface throughout points in the day, the recipe is set for at least some periods of freezing rain – precipitation that falls as rain, and then freezes on contact with a sub-freezing surface.

During the middle portion of the day, temperatures should be warm enough at the surface to support plain rain for some time, before transitioning back into freezing rain, rain/snow mix, perhaps with a period of all snow before tapering off Saturday evening.

output_QGEuaq — NAM output of temperature profiles at about 4,800 feet between 10AM and 7PM Saturday. Notice the light pink indicating temperatures between 0ºC and 10ºC, which only gives way to below freezing temperatures (light blue, indicating 0ºC to -10ºC) later in the time frame. The center of the Nor’easter is located within the middle of the set of concentric rings you see near NYC.

Deviations in the storm track to the east would result in more cold air being pulled in from the action of northerly winds on the western side of the low pressure center’s cyclonic flow (less freezing rain/rain, more snow), while deviations of the track west would result in warmer air being in place (less snow, more rain). So, even a slight adjustment in the storm track could alter the thermal profiles, and subsequently what kind of precipitation we see.

Sunday – temperatures overnight Saturday will be below freezing, which would allow anything that fell and melted to refreeze. Things do clear up Sunday, with highs about average in the mid-30s, and with clouds diminishing.

Monday – there is a chance for yet another round of mainly snow, potentially heavy, as another coastal storm is possible. Highs will be close to the freezing mark, making this an all snow event if it should pan out.

NYC Weekend Weather – Jan 15, 2014

January 15, 2015NYC, Rain, Snow, Storms, Weather Update, Weekendcoastal low, cold front, high pressure, low pressure, new york city weather, nyc weather, nyc wx, pressure gradient, warm front, weather, weekend weather, wxLei Zhao

We end this week off with a windy day Friday, followed by an intrusion of cold air on Saturday before a warmup Sunday that should be accompanied by some rain during the day, then possibly a mix of rain and snow Sunday night. Some chance of snow persists into early Monday.

Friday – a cold front dropping from Canada will tighten the pressure gradient ahead of it, bringing with it breezy west-northwest winds between 15-25mph during the day tomorrow. High temperatures will be about normal in the upper 30s, but with wind chill values only in the 20s.

Saturday – subsequent to the passage of that cold front, we get another shot of cold, arctic air, with temperatures on Saturday struggling to even reach 30 in the city, and only in the 20s elsewhere.

Sunday – a low pressure system will be moving steadily northeast into Quebec by Sunday. This storm system will have a trailing cold front as well as a preceding warm front. We should enter the warm sector behind the warm front passing over us Sunday. This will allow for temperatures to rise into the mid-40s (possibly higher in a few spots). There will be a transfer of energy to a secondary low pressure center which is forecast to form off the Mid-Atlantic coast. This will result in the chance for us to get a few periods of moderate-heavy rain on Sunday, especially in the afternoon hours. As the coastal low moves off to the northeast, rain should taper down during the overnight hours into Monday, and temperatures will be cold enough to support a chance of rain/snow mix.

Monday – snow showers should end early Monday. High temperatures will be about average for this time of year, in the upper 30s.

NYC Christmas Weather Update – Dec 24, 2014

December 24, 2014NYC, Rain, Thunderstorms, Weather Update, Weekendchristmas weather, cold front, gfs, holiday weather, nam, nyc weather, nyc wx, rain, warm front, xmas, xmas wx, xmas wx nycLei Zhao

A foggy start to the busy travel day for many will feature periods of locally heavy rain and gusty winds later this morning into the early afternoon. Near record warmth with high temperatures in the low 60s today will give way to cooler but calmer weather going into the holiday weekend before another round of unsettled weather early-mid next week.

Today – foggy conditions will be a prelude to a stormy Christmas Eve. An approaching warm front will move through shortly and allow for a surge of warm air to raise temperatures into the low 60s. Along with this, there looks to be a period of widespread showers in the late morning and early afternoon hours. Afterwards, there should be a lull in the rain before a second round of showers and possibly scattered thunderstorms associated with this storm system’s trailing cold front moves in. Winds will pick up ahead of and then behind this cold front. If you are traveling either by air or car, the latter part of the day could see some weather related disruptions and delays. Overnight lows will be very mild near 50.

NAM model stimulated radar image for 2PM EST, 12/24/2014

Christmas Day – conditions improve dramatically during the day in the wake of the cold front. Any lingering showers should end early in the morning with rapidly clearing skies accompanied by a gusty west wind. High temperatures in the mid-50s will actually be set early in the morning with temperatures dropping steadily during the day to the upper 40s later in the afternoon.

Friday – fair weather continues as an area of high pressure builds over the Eastern US. Partly cloudy with a mild high near 50.

Saturday – much the same as Friday with high pressure still in control. High again near 50.

Sunday – mostly cloudy with a chance of rain, slightly cooler with highs in the mid-40s. A frontal boundary may stall just south of us, setting up conditions for an extended period of unsettled weather next week.

NYC Weekend Weather Update – Dec 19, 2014

December 19, 2014NYC, Precipitation Type, Rain, Snow, Storms, Weather Update, Weekendchristmas weather, high pressure, low pressure, new york city weather, nyc weather, nyc weekend weather, nyc wx, rain, snow, storms, weather, weekend weather, white christmas, wxLei Zhao

This weekend will feature about normal temperatures for mid-December, with a small chance of rain/snow on Sunday. Relatively quiet weather during the weekend will give way to an active weather pattern for the first half of next week, with a robust storm system arriving Christmas Eve (all rain, sadly, so no white Christmas for us here in NYC).

Saturday – high pressure currently in control of the weather will erode as it moves east. Clouds cover will increase with high temperatures around 40.

Sunday – easterly winds off the ocean in the wake of high pressure centered over Atlantic Canada will bring some slight chance for precipitation. The lower atmosphere is fairly dry, and is not primed with moisture for precipitation. If precipitation does materialize, temperature profiles are low enough that some snow flakes could be seen, but the overall impact will be negligible. High temperatures will be in the low 40s with cloudy skies.

Monday – a significant storm system will be approaching our region from the Central Plains. Forecast models point to a primary low pressure center over the interior of the country while a secondary low forms along the coast. Ahead of this storm system, some scattered showers could pass over the area Monday. Otherwise, expect a mostly cloudy day with high temperatures in the mid-40s.

Tuesday – coverage of precipitation will increase on Tuesday as that secondary low pressure center draws closer to the area. Warmer, marine air will be in place before a warm front passes over. This should ensure that temperature profiles remain warm enough to preclude the possibility of snow. Temperatures may rise to as high as the 50 degree mark Tuesday.

This early-mid week storm will cause some travel headaches for Christmas, but fortunately, it does appear the majority of precipitation will be in the form of rain.

NYC Weekend Weather & West Coast Storm – Dec 2, 2014

December 4, 2014Climate, Cool Images, Drought, Flooding, Noreaster, NYC, Outside of NYC, Rain, Storms, Weather Update, Weekend, Western UScalifornia drought, california storm, climate, drought, flooding, heavy rain, meteorology, nyc weather, nyc wx, pac energy, pacific storm, rain, weather, west coastLei Zhao

It’s been a up and down week for weather in NYC, with Monday starting out in the mid-60s, then a colder mid-week that featured some mixed precipitation and rain. The end of this week will feature rain and slightly warmer temperatures by Saturday, then a return to colder conditions Sunday into next week. I’m also going to point out some of the spectacular weather brought on by a huge Pacific storm that hit California this week.

Thursday – the remainder of today will be pleasant and sunny, though cold with high temps only in the low 40s.

Friday – clouds will begin to build overnight tonight ahead of the a storm system moving in from the Southern Plains to the Ohio Valley. There is a small chance for scattered showers, otherwise expecting a cloudy day with highs in the mid-40s.

Saturday – rain should overspread the area by Friday night into Saturday. This storm system will be drawing on energy and moisture from the Pacific storm that slammed California earlier this week (discussed below). Combined with influx of Gulf moisture, this setup favors a moderate to at times heavy rain event for Saturday. Temperatures will rise steadily ahead of this storm system as it pushes warm air up. High temperatures Saturday should reach into the mid-50s despite rain and clouds.

gfs_namer_042_1000_850_thick — GFS model output for overnight Friday into Saturday

Sunday – rain should end overnight Saturday, and high pressure from Canada should quickly build in behind this storm system. The positioning of this high pressure, along with the exiting low, will make for a tight pressure gradient, which should allow for stiff northwest winds perhaps in the 15-25mph range. Temperatures will drop back into the low 40s with the arrival the colder Canadian air.

gfs_namer_084_1000_850_thick — GFS model output for Sunday night

Monday – the storm system from Saturday will move offshore, but it appears from model runs that there’s some chance the storm lingers. As the high pressure from Sunday moves off to the northeast, the clockwise flow behind it may draw this offshore area of low pressure back into the area. This could lead to some rain on Monday. It’ll be a mostly cloudy day otherwise with highs in the low 40s.

Pacific Storm Slams California

Earlier this week, California got slammed by a very strong Pacific low. This storm brought on furious rains that dropped 1″+ in many areas of Northern California, with totals as high as 3-4″ in spots near the Coast Range and Sierra, as well as further south in the mountains east of San Diego. These totals represent more rainfall than had fallen in many of these areas all of last year.

You can see from the map below which overlays drought conditions (the deeper the red, the more extreme the drought, with the darkest red representing extreme/record-breaking drought) with rainfall totals from yesterday. You’ll see that much of the heaviest rain did fall over regions worst affected by drought. Sadly, though this is a case of too much of a good thing, as much of this desperately needed rainfall occurred so quickly, it will simply runoff back into the ocean.

Screen Shot 2014-12-04 at 12.08.35 PM — Map of California with drought condition layer (reds/oranges), and rainfall totals from yesterday

NYC Weekend Weather – Nov 20, 2014

November 20, 2014NYC, Outside of NYC, Rain, Storms, Weather Update, Weekendcold front, mid-latitude cyclone, new york city weather, nyc weekend weather, nyc wx, occluded front, thanksgiving nyc weather, thanksgiving weather, warm front, warm sector, weather, weekend weather, wxLei Zhao

We got a break from the arctic chill briefly today, but temperatures will fall again for Friday as a cold front currently sitting on top of us passes through. High pressure builds in Friday allowing for sunny conditions, but temperatures will still not be that warm. A big warm up is in store for the second half of the weekend and we could be hitting a rainy low-mid 60s by Monday.

Friday – following the passage of a cold front sitting over us now, skies will clear up overnight tonight and allow for excellent radiational cooling, so low temperatures will be generally in the upper 20s in the city. High pressure works its way in Friday, but with the influence of a cool west wind, the high temperature will probably still only be near 40.

Saturday – another nice day, with plenty of sun, and temperatures will be slightly warmer in the mid-40s, but the big warm up won’t occur until Sunday.

Sunday – a low pressure center with its origins over the Texas Panhandle will be moving northeast towards our area. A warm front will rotate around in front of it, allowing for the influx of a comparatively very warm and moist airmass into the area. The chance of rain will increase steadily along with cloud cover throughout the day Sunday such that by the late evening, showers will be likely. High temperatures should be in the mid-50s.

gfs_namer_081_1000_850_thick — Significant warm up ahead for the latter half of the weekend going into early next week

Monday – as the forecast map from the Weather Prediction Center below shows, the low pressure system from the map above is forecast to intensify significantly as it pulls northeast. This is a classic, mature mid-latitude cyclone with an occluded low and front (purple line extending from the center of the low), a cold front, and a warm front. The warm front will rotate through first, allowing us to get into the warm sector, where there will be plenty of energy and moisture for rain, which could occur in periods throughout Monday. High temperatures will be balmy in the mid-60s.

Thanksgiving Storm?

The chance of a significant Thanksgiving storm is decreasing, though not completely nil. Once the cold front above passes, we’ll see a return to cooler temperatures in the low 50s. It’s worth mentioning that the set up behind the cold should once again favor lake effect snow, so if you’re traveling to any of the usual snow belt areas around the Great Lakes, be prepared.

LZ | Weather

Weather updates & posts for NYC region