All posts by Lei Zhao

NYC Weekend Weather – Mar 09, 2017

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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 Weather Update – Mar 6, 2017

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The week starts off with a thaw from the Arctic cold we experienced over the weekend. We settle into a familiar pattern of a warm front then cold front passage that will see temperatures swing up into the low-60s mid-week before dropping back to seasonable levels towards the late week period.4

Rest of today – mostly sunny, with winds now shifting to the south, high temperatures should reach into the low-40s.

Tuesday – much warmer with high temperatures in the mid-50s, mostly cloudy with a chance for rain due to a cold front approaching. Rain chances increase heading towards the overnight hours.

Wednesday – rain tapering off early, then conditions improving to mostly sunny. High temperatures still forecast to reach the low-60s before the cold front actually passes through.

Thursday – temperatures fall back into the mid-upper 40s behind the cold front with mostly sunny skies.

 

Return to Normal Temperatures to Last

Looking ahead, it appears in the medium term that temperatures will moderate into seasonable mid-40s or lower and stay that way until late in the month. We could see a couple more shots at accumulating snow during this stretch.

 

NYC Weekend Weather – Mar 3, 2017

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The record breaking warmth of only a couple days ago seems like ancient history. We could see some snow flurries to kick off the weekend, then a very cold airmass takes hold with temperatures well below normal. Another warm up is in store to start next week.

Rest of today – mostly sunny to clear skies to start. High temperatures near 40°F. Later in the day, and into the evening hours, an arctic front is forecast to pass through. Snow showers are anticipated to accompany this frontal boundary, though they should not result in any appreciable accumulation.

Saturday – behind the passage of this arctic front, winds shift to the northwest and pick up into the 15-25mph range, with stronger gusts. High temperatures will struggle to top freezing even with lots of sun, as overnight lows will be around 20°F. Wind chills will be in the teens or lower.

Sunday – overnight into Sunday, low temperatures are expected to drop into the teens. Sunny conditions prevail, with slightly warmer temperatures in the mid-30s.

Monday – a warm front will push through, finally breaking the spell of very cold weather. Temperatures should warm up into the upper-40s to near 50°F as clouds increase.

NYC Weather Update – Feb 27, 2017

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The beginning of this week will somewhat echo the end of last week, with temperatures starting off on the cooler side, then ramping up before the passage of a cold front that could also bring some thunderstorms. After this cold front passes, temperatures take a dive closer to normal levels.

Rest of today – increasing clouds will cap temperatures in the low-50s.

Tuesday – warmer but with increasing chances for rain during the day. High temperatures in the upper-50s.

Wednesday – during the early morning hours, a warm front associated with a low pressure center moving across southern Ontario will push through. This will set the stage for possibly record-breaking warmth during the day. Southwest flow will allow temperatures to steadily climb into the upper-60s and possibly over 70°F. Later in the day, a trailing cold front will make its approach. This will serve as a trigger for showers and thunderstorms to develop late in the day and into the early overnight hours. Some of the storms could approach marginally severe criteria.

Thursday – following the cold front passing through, winds shift to the northwest. This will result in much cooler temperatures dropping through the day into the upper-40s.

 

Cooler Weather Ahead

Looking ahead to the mid-month period, it does appear we may see some cooler than normal temperatures prior to the formal onset of spring.

NYC Weekend Weather – Feb 24, 2017

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Enjoy the spring like temperatures while they last. A strong cold front is set to pass through the area late Saturday. Behind this front, temperatures will return to the low-50s, and perhaps colder. Looking ahead for the next week or so, it appears we will see a cyclical pattern of warm weather ahead of storm systems followed by a rush of colder air.

Rest of today – mild, clear skies, high temperatures have already hit nearly 70°F. Overnight, temperatures drop into the low-50s.

Saturday – still quite warm, near 60°F, but with overcast skies and chances for precipitation ramping up through the afternoon hours. A line of moderate to heavy rain is expected to pass through sometime in the early evening hours. Some thunderstorms may be possible with this line of storms.

Sunday – behind this cold front Saturday, temperatures crash back to normal in the mid-40s wtih sunny skies.

Monday – slightly warmer, mostly sunny, with high pressure in control. High around 50°F.

NYC Weather Update – Feb 20, 2017

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This week will see a marked transition from seasonable high temperatures in the low-40s to a much warmer period mid-late week that will be reminiscent of this past weekend’s record-breaking warmth. The only blemish on this spring preview is a slight chance for rain overnight Tuesday. Looking ahead, it appears March will be far from a lamb this year with a few storms rolling our way.

Rest of today – mild and above average with temperatures in the mid-upper 40s. Clear skies overhead. This will continue overnight and allow for good radiational cooling leading to overnight lows in the low-30s.

Tuesday – seasonable with high temperatures in the low-40s under mostly sunny skies.

Wednesday – a warm up begins as a summer-like high pressure area sets up over Bermuda. This high pressure will induce a southwest flow ahead of a cold front to the west that will push warm air from the Southeast to our region. The result will be increasing clouds but high temperatures near 60°F.

Thursday – even warmer, with high temperatures reaching well into the mid-upper 60s with mostly sunny skies.

 

Warm Temperatures to Continue Through Weekend

I suppose Staten Island Chuck was right when he predicted a short winter, because it looks like above normal temperatures are expected through the end of this month. This weekend, look forward to more temperatures near 60ºF.

NYC Weekend Weather – Feb 17, 2017

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This weekend will be characterized by well above normal temperatures and fair conditions. This warm trend looks to continue into next week, and perhaps beyond. Enjoy the warmth, and the early preview of spring!

Rest of today – normal high temperatures around 40°F with sunny skies.

Saturday – significantly warmer, sunny, with high temperatures in the mid-50s as a warm front pushes through.

Sunday – warm again, possibly warmer than Saturday with temperatures approaching 60°F. High pressure to the southwest will continue to pump warm air from the deep south our way.

Monday – cooler, though still above normal, with high temperature around 50°F and sunny.

 

Warm Trend to Continue

Climate Prediction Center points to a high likelihood for above normal temperatures in the next 6-10 days for much of the Eastern United States. Looking ahead, after a brief cool down to begin next week, temperatures go right back up into the mid-upper 50s by the middle of next week.

NYC Weather Update – Feb 14, 2017

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After a wild week of weather last week, things are markedly calmer this week. Temperatures will stay slightly below normal for the duration of the week. We get only a very slight chance at precipitation on Wednesday, otherwise, dry conditions prevail.

Rest of today – a cloudy start to the day should give way to more sun later on. However, temperatures will still be just below normal with highs expected around 40ºF.

Wednesday – a storm system passing to the north will push a warm front through, raising temperatures into the mid-40s and also giving us a slight chance for rain. Mostly cloudy skies.

Thursday – once that trailing cold front pictured above moves through, temperatures once again drop to below normal levels in the upper-30s. Winds pick up from the northwest yielding even colder wind chills in the upper-20s.

Friday – sunnier, and less windy, but temperatures expected to remain below normal again in the upper-30s.

 

NYC Weekend Weather – Feb 10, 2017

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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

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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.