All posts by Lei Zhao

NYC Weather Update – Nov 16, 2015

This week will feature a mixed bag of warm and cool temperatures, along with a bout of moderate-heavy rain and even a couple thunderstorms associated with a cold front passing through the region on Thursday into Friday. Timing of this frontal passage isn’t 100% certain at this point. However, it is clear that behind this front, temperatures will take a dive into more seasonable ranges in the upper-40s to around 50ºF by this weekend.

Rest of today – clear skies with a high temperature well into the mid-60s. This is due in part to high pressure to our south that’s allowing for warm air to flow in from the west.

Tuesday – quite a different story in terms of temperatures. A backdoor cold front pushes through overnight, leading to a shift in winds to the northeast by tomorrow. This wind pattern favors cooler temperatures as the winds circulating clockwise around a high pressure center over the Canadian Maritimes bring in a cooler airmass. High temperatures will struggle to hit 50ºF in this atmosphere.

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Wednesday – temperatures quickly rebound as winds switch back to the south-southeast ahead of a cold front which will be passing through the area sometime late Thursday. Cloud should increase during the day, but enough sun should still get through to get temperatures back to near 60.

Thursday – a mostly cloudy day with periods of rain throughout looks to be the headline for Thursday. Temperatures should warm up nicely into the mid-60s with warm, moist air entering the area from the south ahead of the actual cold front. Periods of heavy rain at times could be accompanied by an occasional thunderstorm especially as the cold front nears.gfs_namer_075_1000_850_thick 2

 

 

 

NYC Weekend Weather – Nov 12, 2015

Periods of rain this afternoon give way to drier weather over the weekend as a cold front passes through late today into the overnight hours. Drier weather prevails this weekend, though with the passage of this cold front, gusty northwest winds will enter the region, bringing in significantly cooler temperatures for Saturday. Temperatures rebound Sunday as we enter another period of slightly above normal temperatures.

Rest of today – showers have moved out of the area at this point, but a few scattered showers may still pop up later today. Otherwise, cloudy with high temperatures already peaking around 60.

Friday – mostly sunny with winds from the west in the 15-20mph range, gusts up to 30mph.

Saturday – winds again in the 15-20mph range with gusts up to 30-35mph. Sunny skies, but temperatures well below normal in the upper-40s, highs may not break 50 in the city. With the winds, it will feel like temperatures are in the upper-30s to low-40s.

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Sunday – winds finally start subsiding, and temperatures will rebound back to around normal in the mid-50s with sunny skies.

Monday – as the high pressure depicted above begins moving to our east, southwest flow on its backside will bring temperatures back into the low-60s.

 

NYC Weather Update – Nov 9, 2015

We have a fairly active weather week ahead of us, with two separate chances for rain coming from two different storms, the first of which impacts the area tomorrow and tomorrow night. The second storm system to affect us this week will make its passage on Thursday. Temperatures are much more seasonable this week with high temperatures hovering near 60 for most of the week.

Rest of today – mostly sunny with a high near 60 degrees.

Tuesday – a low pressure center over the Gulf coast today will strengthen into a coastal low as it tracks to our south and east Tuesday and Tuesday night. Like most coastal lows of this type, a large shield of overrunning precipitation will advance ahead of the actual low. This should translate to a rainy day Tuesday, with steady chances for precipitation throughout the course of the day and into the overnight hours. An east wind will also bring a cool, onshore breeze into the area, giving the day a raw feel despite high temperatures near 60.

 

 

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Wednesday (Veterans Day) – looks to be bookended by wet weather, but should be a mostly dry day with more clouds than sun, and a high again near 60.

Thursday – a cold front associated with a low pressure system that’s currently over the plains will bring about our second chance for rain this week, although this round of rain should not be as long-lived or drenching as tomorrow’s storm. High temperatures should remain around 60.

NYC Weekend Weather – Nov 5, 2015

The warm trend we’ve enjoyed this week comes to an abrupt halt over the weekend as we return to seasonable highs in the upper-50s. We are due to enjoy a couple more days of much above average warmth beforehand, as we’re now in the warm sector south of a warm front that has pushed through and west of a cold front due in late Friday and into the overnight hours Saturday.

Rest of today – mostly cloudy with a high in the upper-60s. A slight chance of rain especially later in the afternoon.

Friday – we’ll be firmly within the warm sector tomorrow with a steady southwesterly flow. Warm air will work its way into the area and yield near record-breaking temperatures in the mid-70s, and possibly even warmer if there are any breaks for sun. There will be another chance at rain tomorrow afternoon and evening as the cold front nears and passes through.  noaad2

Saturday – a marked change in sensible weather is on tap for Saturday once the cold front passes through the region. Skies should clear from west to east over the day, but high temperatures will only be in the low-60s.

Sunday – even cooler, with highs only in the mid-50s under sunny skies.

NYC Weather Update – Nov 2, 2015

It’s the first week of November, but it will feel more like late September with the warm temperatures that are on tap for this week. A robust ridge of high pressure will set up over the area and persist through most of the week, allowing for a very mild airmass to build into the region and set the stage for some unseasonable warmth.

Rest of today – cloudy with high temperatures in the mid-60s.

Tuesday – clouds clear out with high temperatures warming into the low-70s.

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Wednesday – warm temperatures continue with highs around 70 and sunny skies.

Thursday – more clouds than sun, but warm again with a high near 70.

NYC Halloween/Marathon/World Series Weekend Weather, Sandy Retrospective – Oct 30, 2015

After a brief warmup mid-week, we return to more seasonable fall weather for the weekend. Luckily, it appears that this weekend should be rain free, providing excellent conditions for Halloween revelers, Mets fans, and NYC Marathon runners alike. It was quite a different story 3 years ago this weekend, when the city and indeed the entire region was just beginning to comprehend the scope and magnitude of the destruction wrought by a once in 500 year storm: Hurricane Sandy.

Rest of today – sunny, with a high right around average at 60ºF. It will be a chilly evening with lows in the 40s. Temperatures during game time at Citi Field should be in the low-50s.

Saturday – cooler, with highs in the mid-50s, but again with plenty of sun with high pressure in the vicinity. Temperatures for trick-or-treaters out there should again be in the low-50s range tomorrow afternoon and early evening. Weather for World Series game 4 should also be in that low-50s range.

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Sunday – AM temperatures should at race time for the marathon should be hovering right around the 50ºF mark with only a light wind. High temperatures warm up into the low-60s later in the day with a warm front moving through. Temperatures won’t cool off that much during the early evening hours, so if the Mets do make it to game 5, conditions should be good for viewing the game. There is only a slight chance for showers overnight into Sunday.

Monday – clouds and sun on Monday with temperatures climbing into the low-mid 60s.

 

Hurricane Sandy Retrospective

Yesterday marked the 3-year anniversary of Hurricane Sandy’s landfall on the central New Jersey coast. Sandy was in many ways a uniquely devastating force of nature: as it matured, it’s size ballooned, allowing for it to push up a significant storm surge ahead of it. Unlike most mature tropical cyclones that reach the mid-latitudes, Sandy did not recurve out to sea and spare the East Coast. At these latitudes, the predominant wind patterns are from the west (the westerlies), and there’s usually a cold front that pushes tropical cyclones to the east. In Sandy’s case, a low pressure system to its northwest actually produced the opposite effect: Sandy was pulled to the northwest along the counterclockwise cyclonic flow around that low pressure system. This resulted in a historic landfall on costal New Jersey. As the forecast models came into consensus on this result, I began to fear for the worst. Because Hurricane Irene had passed the previous year with great hype, but minimal damage, I had a bad feeling that many New Yorkers would not heed the warnings about this monster storm, even though there was high confidence in an historic event about to unfold.

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A monster storm

Sandy’s landfall also coincided with a supermoon high-tide, which meant that its already significant storm surge was augmented that much more by the pull of the moon. This resulted in catastrophic storm surge inundation along a vast expanse of the Northeast. The geology and bathymetry of New York Harbor made it all the more susceptible to storm surge, as its funnel shape served to channel and amplify Sandy’s storm surge. The fact that Sandy made its land fall to the south of New York meant that its most damaging northeast quadrant (Northern Hemisphere cyclones get a boost in the northeast quadrant because the direction of winds in that quadrant coincide with the direction of the Earth’s Coriolis force) hit the city dead on. A record-breaking storm tied of 14 feet was recorded at The Battery in Manhattan, smashing the previous record of 10 feet.

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Scenes of utter destruction like the one below were commonplace. Over 100 deaths were recorded, with areas like Staten Island’s east coast and the Rockaways particularly badly hit. The costs of the damage ran over $60 billion dollars. To this day, many people’s lives still have not returned to normal, many are still not able to move back into their homes.

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On a personal level, I was very fortunate to be in a neighborhood that was left high and dry, and crucially with power. Along with thousands of other New Yorkers, I felt an urgent and compelling need to get out on the ground and help our neighbors who were hardest hit and who had lost so much. My wife, who had just started working at a new school, found out that week that one of her coworkers had been killed – crushed by a fallen tree – during the storm. My volunteer work after the storm took me to many areas of New York City that I had not explored before. I saw witnessed scenes that I will never forget. For me, this day will always entail with it a sense of grieving, and will alway serve as a reminder to remain vigilant, because the storm that we never thought would happen here did – and could again.

NYC Weather Update – Oct 26, 2015

The weather story this week will feature a storm system that will be drawing on the remnant moisture from Hurricane Patricia and producing some heavy rain on Wednesday as it passes through the region. Aside from a wet day Wednesday, the remainder of the week looks to be dry with decently warm temperatures.

Rest of today – clear with high temperatures near 60.

Tuesday – mostly sunny with clouds increasing later in the day. High temperatures again near 60.

Wednesday – a low pressure center is expected to form over the Great Lakes region and strengthen Wednesday. A warm front attached to this low pressure center will pass through the region late Wednesday. Increasing chance for more widespread rain as the day progresses with a high temperature in the mid-60s. Some urban flooding could occur. Most of the heaviest rain will likely be falling in the late evening and overnight hours.gfs_namer_054_1000_850_thick

Thursday – could see a few showers in the morning, but then skies should begin to clear and allow for temperatures to warm up into the mid-60s again before a cold front drops through.

 

Drought Update

We’re hoping for the rains Wednesday to make a dent in the stubborn moderate drought that continues to cling to the metro area, in particular Long Island.

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NYC Weekend Weather – Oct 22, 2015

The warm spell that we’ve enjoyed in the city up to this point will be ending tomorrow. While temperatures will cool off this weekend, we won’t be seeing anything close to the chilly lows we saw last weekend. We’ll have good weather Saturday before another cold front pushes through late Saturday into Sunday, which could spark off a few showers.

Rest of today – temperatures are surging into the mid-70s ahead of a cold front that will push through later today and overnight. There could be a small chance for showers associated with this cold front later, though it’s more likely this front will be dry.

Friday – high pressure builds behind this passing cold front. Cooler temperatures with highs only around 60 in the wake of this cold front despite plenty of sunshine.

Saturday – temperatures will be similar to Friday, but with clouds on the increase as another cold front approaches late Saturday. Some showers may occur with this cold front passing through overnight into Sunday morning.

Sunday – warmer with high temperatures in the mid-60s before the cold front passes. A chance of showers early, and the mostly cloudy.

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Fall Foliage

This weekend should have good conditions for anyone traveling upstate apple picking or viewing fall colors. Check out this map to see where the foliage has peaked.

NYC Weather Update – Oct 19, 2015

This weekend featured much below normal temperatures for this time of year and several rounds of frosts/hard freezes. The frigid airmass responsible for these temperatures will finally be pushed north of the area tomorrow as high pressure builds over the Southeastern United States. Return flow from the south and southwest around this area of high pressure should lead to temperatures that will be in the normal to above normal range for the majority of this week.

Rest of today – still chilly today with high temperatures only topping out around 50 in the city and cooler in the surrounding suburbs under mostly clear skies.

Tuesday – clockwise flow around an area of high pressure building to our south will enable southwesterly and westerly winds to usher in a much warmer airmass into the region. Temperatures should rebound nicely tomorrow into the mid-upper 60s in the city with partly sunny skies.

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Wednesday – the warm trend continues, with temperatures Wednesday expected to be similar if not even a couple degrees warmer in the low-70s.

Thursday – a cold front will be approaching from the northwest on Thursday, so clouds are expected to increase ahead of it, though no rain is expected at this time. Prior to the passage of this cold front, temperatures should remain warm in the upper-60s to near 70 again.

NYC Weekend Weather – Oct 15, 2015

If you like crisp, cool, fall weather, then this coming weekend is for you. Following a cold front moving through tonight into tomorrow, temperatures this weekend will feel more like November than October, with highs only in the low-50s on Sunday. Depending on wind conditions, this Sunday and Monday morning may see the first frosts/freezes of the season. The cooler than normal temperature trend continues into Monday, but warmer temperatures return by mid-week next week.

Rest of today – an archetypal fall day with high temperatures right around normal in the mid-60s and a clear sky.

Friday – mostly cloudy to start the day with some very small chance at rain as a cold front passes over. Once the front clears the region, skies should clear and temperatures will actually be a bit warmer in the mid-upper 60s.

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Saturday – behind the cold front passing on Friday, temperatures take a plunge with gusty northwest winds flowing around an area of high pressure building to our west. High temperatures will probably not break 60ºF in the city, even cooler in the outlying suburbs.

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Sunday –  the airmass associated with this high pressure will likely set off the first snows of the season in parts of the Upper Midwest. Not surprisingly, this will translate to chilly temperatures Saturday night, Sunday and Monday. Lows overnight into Sunday will be in the upper-30s in the city (brrr). Frost may develop on Sunday morning in interior areas, ending the growing season. High temperatures Sunday will struggle to hit the mid-50s in the city.

Monday – basically a repeat of Sunday, same crisp, cool conditions with high temperatures in the mid-50s.