Heavy Rain Drenches NYC and Its Subways

An intense rainstorm swept through New York City on Monday. With bands of torrential downpours, it unleashed more than half a month’s worth of rain in just a few hours.

According to the NWS, 2.82 inches of rain was measured in Central Park. While that is an impressive total, it did not break the daily rainfall record for the date. That honor belongs to April 16, 1983 when 3.29 inches of rain was reported. New York City, on average, gets 4.50 inches of rain for the entire month of April.

The heavy rain caused flash flooding and disrupted travel across the city. Torrents of water poured into several subway stations through leaks in the ceiling and down the entrance/exit steps. During the morning commute, the MTA announced that several stops, including the 145th St station on the Number 1 line and the 42nd St-Bryant Park stop on the F and M lines, would be bypassed because of “excess water”.  Significant delays and cancellations were also reported at the area’s airports.

This type of heavy rain event, according to NOAA, is expected to become more common in the northeast as global temperatures rise and precipitation patterns change.

Heavy rain sends water cascading down the steps of the 145th St Station of the No. 1 train in NYC. Credit: Josh Guild/Twitter.

Summer Preview Brings NYC First 80° of the Year

It felt more like June than April in New York City on Friday. The temperature in Central Park soared to 82°F, marking the city’s first 80-degree day of the year.

Topping out at 22°F above average, the day was more than unseasonably warm. However, it was not a record breaker. That honor belongs to April 13, 1977, when the mercury soared to 88°F. The low temperature was 60°F, which ironically is the normal high for the date.

After an extended winter that included four nor’easters in March and a snowy start to April, many New Yorkers took full advantage of this summer preview. The parks and outdoor cafes were packed.

This spring heat was the result of a ridge in the jet-stream that allowed warm southern air to move further north than it normally would at this time of year.  While the balmy conditions are forecast to remain in place through Saturday, temperatures are expected to plummet into the 40s on Sunday. So, enjoy it while it lasts, but get ready for weather whiplash!

A summer preview for NYC. Credit: The Weather Gamut

Spring Storm Sets New Daily Snowfall Record in NYC

A spring snowstorm slammed the northeastern United States on Monday. Coming on the heels of a mild Easter weekend, it felt like weather whiplash across the region.

Here in New York City, the storm dumped 5.5 inches of snow in Central Park, setting a new daily snowfall record for the date. The previous record of 2 inches had been in place since 1871. The storm also marked the snowiest April day the city has seen in 36 years.

Despite the ground being relatively warm, the heavy, wet snow was able to accumulate because it came down very quickly. La Guardia Airport reported a snowfall rate of 2 inches per hour.

The city, on average, gets 0.6 inches of snow for the entire month of April.

Source: NWS

March 2018 was More of a Lion Than a Lamb in NYC

There is an old saying that March comes in like a lion and goes out like a lamb. It refers to the transition from winter to spring that takes place during the month and the change in weather that usually follows. In New York City this year, however, that tradition went out the window as March turned out to be colder than February.

This type of temperature flip-flop, according to the NWS, has only occurred three other times in New York City history – 1890, 1891, and 2017.

This March, twenty-six out of thirty-one days posted below average temperatures. Four of those days had highs that did not get out of the 30s. In the end, the city’s mean temperature for the month was 40.2°F, which is 2.3°F below normal.

The month was also unusually wet. The four nor’easters that blasted the region in as many weeks brought the city copious amounts of precipitation. In all, we received 5.17 inches of rain, which is 0.81 inches above average. Snowfall was also abundant, with 11.6 inches measured in Central Park. Of that total, 8.4 inches fell during the fourth and final nor’easter of the month. March, on average, usually only brings the city 3.9 inches of snow.

New York City weather records date back to 1869.

March was colder than February in NYC. Credit: The Weather Gamut

Fourth Nor’easter of the Month Slams NYC

The calendar says spring, but it felt more like winter in New York City on Wednesday as the fourth nor’easter of the month slammed the region.

According to the NWS, the storm dumped 8.4 inches of heavy, wet snow in Central Park, setting a new daily snowfall record for the date. The previous record of 7.1 inches had been in place since 1958. The city, on average, gets 3.9 inches of snow for the entire month of March.

This storm was the fourth nor’easter to affect the city and region in less than three weeks. The others were on March 2, March 7, and March 13. This one, however, was by far the snowiest. It was also the first time since 1992 that the city saw at least 6 inches of snow from a spring storm.

The reason for the plethora of nor’easters this month involves something called the North Atlantic Oscillation (NAO). Stuck in its negative phase for weeks, it has caused the jet stream to dip south over the eastern US and steer storms toward the northeastern seaboard.

View of the fourth nor’easter to hit the east coast this March. Credit:  RAMMB/CIRA/CSU

Second Nor’easter in Less Than a Week for NYC

For the second time in less than a week, a nor’easter slammed New York City.

The storm intensified quickly and brought heavy snow, strong winds, and even thundersnow to the area. It downed trees and caused a number of travel disruptions, including nearly 2000 flight cancelations and the temporary suspension of all NYC Ferry service.

While the snow fell quickly, the surface temperature hovered just above freezing and did not allow much to accumulate. Only 3.2 inches of snow was reported in Central Park, according to the NWS. Areas north and west of the city received much higher storm totals.

GOES-16 image of nor’easter on March 7, 2018. Credit: NOAA

Weather Lingo: Venturi Effect

March, a transitional month between winter and spring, is well known for its winds. In large cities like New York, however, the wind can be accelerated by something called the Venturi Effect.

Tall buildings and straight, grid-like streets essentially create man-made canyons that affect how the wind moves through a city. Funneled through the buildings, the wind is constricted and forced to speed up. The same process is seen when you put your thumb over the mouth of a hose to create a choke point and make the water flow faster.

The Venturi Effect is named for Giovanni Battista Venturi, an 18th-century Italian physicist.

Credit: Currents

Powerful Nor’easter Slams NYC

A powerful nor’easter slammed the northeastern United States on Friday. Heavy precipitation, strong winds, and coastal flooding were reported across the region.

LGA airport. Credit: Chris Rudnick/Instagram

Here in New York City, 2.24 inches of rain fell in Central Park and wind gusts as high as 67mph were reported at JFK airport. These powerful winds canceled hundreds of flights, knocked down trees, and caused power outages in four of the city’s five boroughs. They also tore off a section of the roof of the American Airlines hangar at La Guardia airport and caused two tractor-trailers to flip over on the Verrazano Bridge.

Starting as an area of low pressure moving in from the west, this storm developed into a nor’easter over the Atlantic and then rapidly intensified. It underwent a process known as bombogenesis, the threshold for which is a drop in pressure of 24mb in 24 hours.This storm dropped 26mb in only 21 hours, producing its damaging winds.

Nor’easter of March 2, 2018. Credit: NOAA

February 2018: Warmest on Record in NYC

February 2018 was New York City’s warmest February on record. Its mean temperature of 42°F was a staggering 6.7°F above the long-term norm. The previous record of 41.6°F was set just last year in February 2017.

Overall, we had nineteen out of twenty-eight days that were warmer than normal. Five of those produced readings in the 60s and one even hit 78°F, marking the warmest February day ever recorded in NYC. A record warm minimum temperature was also set on February 21 when the city only cooled down to 55°F. The average low for that date is 30°F.

While a few warm days in February are not that uncommon, this extended pattern of sustained warmth was very unusual. Driven largely by a persistent ridge in the jet stream, warm southern air was funneled northward almost continuously throughout the month.

February is usually the city’s snowiest month on the calendar, but Central Park only received 4.9 inches of snow this year. That is 4.3 inches below normal. Of that total, 4.4 inches fell during a single, quick-hitting storm when the air was briefly cold enough to support frozen precipitation.

Rainfall, on the other hand, was abundant with seventeen days posting measurable precipitation. In total, Central Park reported 5.83 inches of rain. That is 2.74 inches above average.

New York City weather records date back to 1869.

February 2018 was the warmest February on record in NYC. Credit: The Weather Gamut

Spring Preview Brings NYC Warmest February Day Ever Recorded

The calendar says February, but it felt more like May in New York City on Wednesday. The temperature in Central Park soared to 78°F, setting not only a new record high for the date but marked the warmest February day ever recorded in the Big Apple.

Records are usually broken by fractions of a degree, but these were shattered. According to the NWS, the previous daily record, which was set in 1930, was 68°F and the former record monthly high that had been in place since February 24, 1985, was of 75°F. The city’s normal high this time of year is 43°F.

The primary driver of these unusually balmy conditions is a strong Bermuda High off the east coast of the US. Spinning clockwise, it is funneling warm southern air into the region.

Venturing out without coats and enjoying lunch alfresco, many New Yorkers took full advantage of this early spring preview. Personally, however, it felt a little surreal. February is typically the snowiest month of the year in NYC – a time when sledding and ice-skating are more common than ice-cream trucks and frisbees.

That said, these spring-like conditions will be short-lived. Temperatures are expected to return to more seasonable levels tomorrow. Get ready for weather whiplash!

Temperatures soared to record levels in NYC on Feb 21. Credit: The Weather Gamut