All posts by Lei Zhao

NYC Weekend Weather – Feb 4, 2016

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We have had a very warm start to the month of February, and it sure does feel like the groundhogs were right that there will an early spring. Even if that is to be the case, we are still technically in the depths of winter, and the weather over the next couple of weeks will remind us of that fact. The end of this week and this weekend will be relatively quiet on the weather front, but looking ahead at the beginning of next week, there is a potential for a coastal storm that could bring us some more snow.

Rest of today – mostly cloudy with some breaks of sun, warm but with temperatures dropping through the 50s during the day.

Friday – the cold front that passed through yesterday will stall out at sea, but close enough to us that another impulse of low pressure moving along it could bring some light snow to southern and eastern portions of the NYC region. Light, wet, accumulating snow is possible for NYC and Long Island. Depending on the storm track, some areas of eastern Long Island could pick up 3″, while areas west closer to the city see a coating to an inch overnight. During the day Friday, temperatures will cool off noticeably into the low-40s and the winds will pick up as skies clear.

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Saturday – a nice day, with mostly sunny skies and highs in the low-mid 40s.

Sunday – essentially a clone of Saturday in terms of sensible weather, mostly sunny, highs in the low-mid 40s.

 

Cooling Off the Next Couple Weeks

It is technically supposed to be the coldest stretch of the year climatologically, so it makes sense that there should be some cooler temperatures coming. In fact, Climate Prediction Center does have normal to below normal temperatures (normal would be in the mid-30s) for the area the next couple of weeks.

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NYC Weather Update – Feb 02, 2016

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The calendar says it’s February, but you’d be forgiven for thinking otherwise with temperatures soaring well into the upper 50s this afternoon. The warm trend continues through the middle of this week, when a potent storm system that will be bringing blizzard conditions to some parts of the Midwest (including Iowa, where caucus turnouts may be adversely impacted) passes through the area. Looking ahead, a cool down is on the way, as is the potential for another coastal storm on the day after the Super Bowl. At this time, thermal profiles are not looking conducive for snow, but as we all saw from the last storm, things could very well change as this storm system evolves.

Rest of today – quite warm, with high temperatures well in the upper 50s under mostly cloudy skies. Periods of light rain look to persist as a cold front makes its way across the area this evening, though it appears most of the precipitation should end by 7PM this evening.

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High Resolution Rapid Refresh model output for 7PM EST

Tuesday – with the cold front passing through tonight, temperatures will moderate tomorrow, dropping into the upper 40s under mostly clear skies.

Wednesday – a complex and potent storm system that will be impacting the Midwest the next couple days will make its way into the region Wednesday. A warm front will pass over our area prior to the passage of a cold front. As we enter the warm sector between these two frontal boundaries, we’ll see a surge of warm air and moisture from the south. This may even lead to a couple isolated rumbles of thunder during the afternoon. Otherwise, expect mostly cloudy skies with showers throughout the afternoon into the evening hours. High temperatures will be quite warm, again approaching 60ºF – and possibly surpassing this mark.

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Thursday – just like tomorrow, once the cold front above pushes through the area, temperatures will again cool off back into the upper 40s (which is still about 10ºF above normal), and skies will clear.

NYC Weekend Weather – Jan 29, 2016

Climate, Drought, Noreaster, NYC, Snow, Weather Update, Weekend, , , , , , , , , , , ,

You’d be forgiven if you didn’t believe that a record-setting Nor’easter blizzard happened less than a week ago. A week of much above average temperatures and warm weather has quickly melted more than half of the snowpack that was left after the blizzard dropped 26.8″ (.1″ short of the all time record) in Central Park, breaking the single day storm total snowfall record with a new high of 26.6″. Except, of course, those huge snow mounds that are trapping your parked car. Warm weather, with high temperatures near or above 50ºF this weekend means that even more of this snow will melt away. Whatever’s left will likely be completely washed away mid-week next week when we’re expected to hit temperatures near 60ºF with thunderstorms possible.

Rest of today – mostly cloudy with a high near 40ºF. A passing rain/snow shower caused by a weak passing disturbance in the upper atmosphere is possible this afternoon around 1PM.

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Saturday – brief clearing caused by an area of high pressure overnight will give way again to increasing clouds with high temperatures around 40ºF again.

Sunday – the high pressure moves quickly off to our east Sunday, allowing for clockwise return flow from the southwest to bring in warmer temperatures in the upper 40s under partly sunny skies.

Monday – warm temperatures continue with highs topping out around 50ºF and partly sunny skies.

 

Cooldown Coming

Don’t get too used to the warm temperatures because after mid-week next week, cold air returns to the Eastern United States for a period.

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Blizzard Brings Drought Relief

One of the best parts about this blizzard was that it brought along some much needed precipitation precisely to areas of the region that most needed it. As you’ll see below, since the blizzard past the area of New York State experiencing moderate drought has decreased from 6.80% to 2.04%, largely because areas of moderate drought in the NYC region and Long Island have gotten slammed with huge amounts of snow that will be replenishing the local watersheds as it melts.

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NYC Weekend Weather – Nor’easter Inbound – Jan 21, 2016

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All eyes turn towards this weekend’s Nor’easter which will bring us the most snow we’ve seen since last winter. Confidence is growing that NYC and points south could receive over a foot of snow by Sunday. In addition, forecasters anticipate that this storm will bring sustained winds of 30mph to coastal areas with gusts as high as 40-60mph leading to whiteout blizzard conditions. However, it is important to not, even at this point, 48 hours from the start of this event, that a good deal of uncertainty remains about these forecast snow totals.

Rest of today – mostly clear with high temperatures reaching into the mid-30s but a northwest wind in the 15mph range making it feel colder.

Friday – slightly cooler with highs in the low-mid 30s, clouds I increasing through the day as the headline storm for the weekend approaches.

Saturday – snow should begin falling from southwest to northeast overnight Friday and continue throughout the day Saturday. Sustained northeast winds 25mph-30mph could lead to drifting and blowing snow, making for hazardous teavel conditions. Some potential exists that enough warmer air wraps into the storm off the Atlantic that some areas see a changeover to a rain/sleet/snow mix in the afternoon before transitioning back to all snow Saturday night. Total daytime accumulations are currently forecast between 3-7″. Overnight accumulations could be in the 4-8″ range.

MinSnowWeb
Minimum snowfall for this Nor’easter
StormTotalSnowWeb1
Most likely snowfall totals
MaxSnowWeb
Maximum snowfall possible with this storm


Sunday – some lingering snow showers are possible Sunday morning but conditions should improve rapidly as cloud cover decreases with the storm exiting to our east. High temperatures are expected to be in the mid-30s.

Monday – warmer with high temperatures in the mid-30s and sunny skies.

Complicating Factors for Forecasting the Nor’easter

  • Model divergence – European models favor a solution that has the storm moving quicker and further south than US based models. This scenario would result in minimal snow for NYC, hence why the minimum snow forecast is only 2″.
  • Unpredictable snow bands – as we are all too aware from last year’s fiasco of subway shutdowns in anticipation for a blizzard that didn’t materialize, when it comes to Nor’easter type storms, where, when, and for how long deformation banding features (heavy bands of snow) set up will make or break a snowfall total forecast in either direction. However, these types of mesoscale banding features are not easy to predict with confidence before they actually start forming. Should parts of our region fall under one of these banding features where snow could be falling at rates of 1″+ per hour, you could easily see total snowfall forecasts be shattered.
  • Intrusion of warm air – if enough warm air works its way into this storm off the warm waters of the Atlantic (where above normal temperatures thus far this winter have kept the sea surface temperatures abnormally warm), then some areas could see a rain/sleet mix for periods of time. Forecasters are overall confident the window for this mixing is small enough that overall totals won’t be dented too much, though.
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The closer this storm center tracks to the 40ºN 70ºW benchmark, the better the chances become for our are to get a lot of snow. Climatologically, Nor’easters that track closest to this benchmark have been the biggest snowmakers for the NYC region.

 

NYC Weather Update – Jan 18, 2016

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Weather to start this week will be rather uneventful, predominantly featuring windy, cold days, but little in the way of precipitation. We did get our first dusting of snow so far this winter in the city last night, and the potential for significantly more exists with a possible Nor’easter coming this weekend. As always, even though we’re within a week of this event, our local forecast office is only forecasting with 30% confidence due to the large changes in impact that even small fluctuations in storm track and intensity could bring.

Rest of today – we’ve already hit high temperatures for the day around 30ºF. A tight pressure gradient is causing breezy west winds near 20mph translating to wind chill values in the 10-15ºF range.

Tuesday – basically a repeat of today, but with slightly stronger winds. High temperatures will be in the upper-20s to around 30ºF with west winds in the 20-25mph leading to wind chills in the single digits to low teens under mostly sunny skies.

Wednesday – warmer, with high temperatures closer to normal in the mid-30s, calmer winds and sunny skies. There could be some flurries Wednesday night with a passing clipper system, but no accumulation is expected in the city.

Thursday – mostly sunny again with high temperatures in the mid-30s.

 

Possible Nor’easter This Friday – Saturday

Looking ahead towards the end of the week, there is a possibility for the first significant snowfall event in the NYC region thus far this winter. Forecasters are keeping close tabs on the possible formation of a classic Nor’easter towards the end of this week. It is important to stress that even at this point in time, there’s still considerable uncertainty about how this scenario will unfold. A deviation in the track of this coastal low too far north would result in a mainly rain event along the coast, while a deviation too far south would mean significantly less precipitation. If this scenario plays out under optimal conditions, our region would be in the northwest quadrant of this low, an area that favors the development of heavy snow. Even then, as was the case a couple winters ago, slight changes to the track and position of the heaviest snow bands could mean the difference between 5″ of snow or over a foot. Stay tuned for updates.

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NYC Weather Update – Jan 11, 2016

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This week will feature below normal temperatures for the most part, with a chance at some snow showers for the first time this winter coming along with an Alberta clipper type system tomorrow afternoon into the overnight hours. Later on this week into the weekend, we are looking at a more potent and complex storm system that could bring a mix of precipitation to the area.

Rest of today – mostly sunny with scattered clouds and a high temperature in the mid-30s. A breezy day with west winds in the 15-20mph range.

Tuesday – partly sunny to start the day, with high temperatures hitting the upper-30s to about 40ºF. Snow flurries/rain could mix together in the afternoon. As temperatures drop after sunset, precipitation should transition to all snow. Due to the quick moving nature of this clipper system, we’re not really expecting any accumulating snow.

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Wednesday – following the passage of the clipper system, winds pick up again from the west in the 15-20mph range, delivering a cold day with partly sunny skies and high temperatures right about freezing.

Thursday – slightly warmer, with high temperatures in the mid-30s, and a calmer wind so not as much of a biting cold.

NYC Weekend Weather – Jan 8, 2016

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With a quiet, though at times very cold, weather week behind us, we look towards a weekend that will bring with it much warmer temperatures along with unsettled weather. Looking into the long term, forecast models are hinting at a possible strong coastal low/Nor’easter hitting the area about 10 days from now. Of course, this far out, forecasts will vary wildly, as has been the case the last week or so with forecast models. However, if the right conditions combine, we could see our first big snow event of the season.

Rest of today – clouds increasing steadily during the day with an approaching storm system. High temperatures about normal in the low-40s.

Saturday – the first portion of a storm system for this weekend moves in during the day Saturday, however, precipitation will be limited during the day due to a lack of significant lift in the atmosphere. Cloudy, with high temperatures in the mid-40s.

Sunday – the bulk of the rain will arrive along with a warm front Sunday. Periods of heavy rain are possible throughout the afternoon, tapering off during the evening hours. Depending on if we get any breaks in the clouds, we could see temperatures approach 60ºF during the day.

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Monday – once the the low pressure system above exits the area, pulling through a trailing cold front, temperatures will once again plummet back into the upper-30s with clear skies.

NYC Weather Update – Jan 4, 2016

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The new year starts off with a blast of Arctic cold that will plunge the mercury down into numbers we haven’t seen since last winter. We will be seeing the coldest weather thus far this winter to start this week, but temperatures will rebound back into above average range mid-week. We won’t be getting any precipitation to go along with this cold air, so no snow still for us this winter.

Rest of today – parts of the area have likely already seen their high temperatures for the day. In the city, we’ll struggle to get above freezing today. An arctic front moved through, and is allowing for much colder air to enter the region. Some parts of eastern Long Island may actually see snow flurries today, but the rest of the region should see mostly sunny skies.

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Tuesday – overnight lows will be downright frigid with temperatures at daybreak only in the teens for the city and single digits elsewhere. Couple that with stiff north winds and we’re looking at wind chill values in the single digits in the city. During the day Tuesday, north winds should slowly subside, but high temperatures will again only be near freezing.

Wednesday – the center of the high pressure responsible for bringing in the cold air will be close to us, meaning winds will become minimal, and will begin to shift from north to southwest as the high pressure continues moving to our east. This will allow for daytime highs to reach back up into the low-40s, which is 6-8ºF above normal.

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Thursday – looking like a very similar day to Wednesday, with high temperatures again in the low-40s and with sunny skies.

NYC New Years Weekend Weather Update – Dec 31, 2015

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The New Year will finally bring some more seasonable weather to the region as temperatures dip in response to a building area of high pressure and west-northwest winds over the weekend. It will be an uneventful weekend otherwise, with generally dry conditions.

Rest of today – mostly cloudy to partly sunny with high temperatures around 50ºF. For New Year’s Eve celebrations tonight, temperatures will drop rather quickly into the low-40s by midnight.

Friday (New Years Day) – cool, though still above normal with high temperatures in the low-40s and sunny skies.

Saturday – cool and dry conditions prevail with high temperatures again in the low-40s. Overnight lows will be in the low-30s.

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Sunday – basically a clone of Saturday, mostly sunny, highs in the low-40s.

NYC Weather Update – Dec 28, 2015

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After an absurdly warm start to the winter, we are about to get a dose of proper weather for this time of year. While temperatures this week and the first half of January will still above normal in many cases, they will be considerably cooler than December and be closer to normal than not. This week, we start with a messy and complex storm (the same that spawned deadly tornadoes in Texas and has brought blizzard conditions to New Mexico, and an ice storm to Oklahoma) that affects the area tonight into Tuesday with a mix of rain, sleet, freezing rain, and snow, depending on how far north you are. Yet another round rain and snow further north from the city is possible Wednesday.

Rest of today – seasonably cool with high temperatures only in the low-mid 40s. Increasing clouds ahead of a warm front that will be the focus for the precipitation later tonight. Things get interesting overnight as precipitation begins to spread over the area from southwest to northeast. Near the coast, surface temperatures are expected to remain warm enough (upper-30s) to largely preclude the possibility of significant wintry precipitation, however, sleet could mix in with rain to at the start of this storm before things shift over to all rain. Further west and north will be another story, with areas expecting anything between .25″ of ice to 2-4″ of snow/sleet accumulation before rain starts falling.

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Tuesday – as temperatures warm with daybreak, wintry precipitation should transition entirely to rain. Rain is expected to last throughout most of the morning into the early afternoon hours. East winds ahead of the warm front mentioned above will be in the 15-20mph range before shifting to the north. High temperatures in the city are expected to hit the upper-40s to around 50ºF.

Wednesday – we’ll get another shot at rain as the cold front railing the warm front pictured above pushes through late on Wednesday into the overnight hours. Despite increasing clouds, forecasts still call for high temperatures in the low-50s.

Thursday – a lingering chance of rain remains on the backside of the cold front. High temperatures are expected to be about the same as Wednesday near 50.