April 2018: Earth’s Third Warmest on Record

Our global temperature continued its upward trend last month with April 2018 marking the third warmest April ever recorded on this planet. Only April 2016 and 2017 were warmer.

According to a report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for the month – over both land and sea surfaces – was 58.19°F. That is 1.49°F above the 20th-century average. April was also the 400th consecutive month with a global temperature above its long-term norm. That means the last time any month posted a below average reading was December 1984.

While heat dominated most of the planet this April, some places were particularly warm, including Central Europe, eastern Russia, and parts of both South America and Australia. These soaring global temperatures are largely attributed to the long-term trend of human-caused climate change. In fact, ENSO neutral conditions were present in the Pacific during April, meaning neither El Niño nor La Niña influenced temperatures.

For many people in the US, however, especially in the eastern part of the county, this April was relatively cold. For the lower 48 states as a whole, it was the 13th coldest April on record. To put this disparity into context, consider that the contiguous United States constitutes less than 2% of the total surface of the Earth. This detail highlights the fact that climate change is a complex global phenomenon that involves much more than the short-term weather that is happening in our own backyards.

Year to date, the first four months of 2018 were the fifth warmest such period of any year on record. Global temperature records date back to 1880.

Credit: NOAA

Suddenly Summer: Record Breaking Spring Heat in NYC

After a long cold winter and a chilly start to spring, it suddenly felt like summer in New York City this week.

According to the NWS, the temperature in Central Park hit 90°F on Wednesday. That marked the city’s first 90°F reading of the year and tied the daily record set in 2001. The sultry conditions continued on Thursday as the temperature climbed to 92°F, setting a new record high for the date. The previous record of 90°F had been in place since 2001.

Thursday’s low of 70°F was another record breaker, surpassing the old record of 68°F from 2001. In fact, this low reading was warmer than the date’s normal high. The city’s average high and low temperatures for this time of year are 67°F and 50°F, respectively.

These dramatic temperatures are the result of a Bermuda High, a large area of high pressure situated off the mid-Atlantic coast. Spinning clockwise, it has created a warm southwesterly flow of air into the northeast.

This summer-like weather brought many New Yorkers out of hibernation and into the city’s numerous parks and outdoor cafes. However, for some, the heat comes with a cost. It can lead to the formation of ground-level ozone, which is why an air quality advisory was issued for the area. Anyone with respiratory concerns, like asthma, has been advised to stay indoors.

While these temperatures are unseasonable, the city has seen 90° readings arrive even earlier. The earliest, according to NWS records, was April 7, 2010, when the mercury climbed to 92°F.

If you are not quite ready for summer, fear not. Conditions more typical of May are expected to return this weekend.

A week of weather whiplash for NYC. Credit: The Weather Gamut

April 2018: Unseasonably Cold and Wet in NYC

April felt like a wild ride of weather in New York City this year. It produced both a record-breaking snowfall and a balmy summer preview with temperatures in the 80s. However, with 19 out 30 days posting below average readings, the cold won out in the end. The city’s mean temperature for the month was 49.5°F, which is 3.6°F below normal.

While unseasonably chilly, the month was not a record breaker. That dubious honor, according the NWS, belongs to April 1874 when the monthly temperature was only 41.1°F. The city’s warmest April on record was April 2010 with a mean temperature of 57.9°F.

In terms of precipitation, this April was unusually wet with 14 out of 30 days producing rain or snow. In all, the city received 5.78 inches of rain, which is 1.28 inches above average. Of that total, 49% fell during a single heavy rain event on April 16. Snow was also abundant with 5.5 inches measured in Central Park. Coming down during a single storm on April 2, it set a new daily snowfall record for the date. On average, the city gets 0.6 inches of snow for the entire month.

April was a wild ride of weather in NYC. Credit: The Weather Gamut

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

Do April Showers Really Bring May Flowers?

The phrase, “April showers bring May flowers “ has been around for centuries. It is derived from a poem written in the 1500s by Thomas Tusser – an English poet and farmer. This old adage, however, does not hold true in the northeastern United States.

Coming on the heels of the snowy months of winter, April typically produces more rain than snow. Many people, therefore, consider it a rainy month. Since water is necessary for the overall survival of plants, they also associate it with the bloom of flowers in May. Nevertheless, according to botanists, perennials – the plants that go dormant in winter and re-grow in the spring – are more dependent on the soil moisture derived from winter snowmelt and the long-term local precipitation pattern.

In the end, though, temperature is the most significant factor in determining when a flower will bloom. As soon as the weather becomes more spring-like, flowers will start to blossom, regardless of how much it rained in April or whatever the prior month was. That said, a “false spring” – a warm spell that triggers flowering but is followed by a hard frost – can kill the fragile blooms.

It is also worth noting that April is not typically the wettest month of the year for most places in the US. In New York City, July, on average, takes that honor because of the downpours associated with its strong summer thunderstorms.

Peonies in bloom. Credit: Melissa Fleming

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

First Day of Spring 2018

Today is the Vernal Equinox, the first day of spring in the northern hemisphere. The new season officially begins at 16:15 UTC, which is 12:15 PM Eastern Daylight Time.

Our astronomical seasons are a product of the tilt of the Earth’s axis – a 23.5° angle – and the movement of the planet around the sun. During the spring months, the Earth’s axis is tilted neither toward nor away from the sun. This position distributes the sun’s energy equally between the northern and southern hemispheres.

Since the winter solstice in December, the arc of the sun’s apparent daily passage across the sky has been getting higher and daylight hours have been increasing. Today, the sun appears directly overhead at the equator and we have approximately equal hours of day and night. The word “equinox” is derived from Latin and means “equal night”.

As a transitional season, spring is a time when the chill of winter fades away and the warmth of summer gradually returns. The most noticeable increases in average daily temperature, however, usually lag the equinox by a few weeks.

Earth’s solstices and equinoxes. Image Credit: NASA