October Begins with Weather Whiplash in NYC

Autumn is a transitional season where a few warm days still pop up as cooler temperatures gradually take hold. This week in New York City, however, it felt like we jumped from mid-July to late October in only one day.

On Wednesday, the temperature soared to a sweltering 93°F, setting a new record high for the date. The previous record of 90°F had been in place since 1927. Then, the temperature plummeted overnight. On Thursday, the mercury only made to 63°F.  While not a record-breaker, it was the coolest day the city has seen in months.

The normal high for this time of year in the Big Apple is around 70°F.

Credit: The Weather Gamut

Record Breaking October Heat in NYC

The season officially changed to autumn last week, but it felt more like summer in New York City on Wednesday.

The temperature in Central Park soared to 93°F, setting a new record high for the date. The previous record of 90°F had been in place since 1927. Wednesday also marked the second warmest October day ever recorded in the Big Apple. Only October 5, 1941, was warmer when the temperature hit an unseasonably sultry 94°F.

This type of heat is unusual for NYC in October. In fact, this was only the sixth time temperatures ventured into the 90s during the month since record-keeping began in 1869.

At this point in October, the normal high in the city is 69°F. But with a stubborn ridge of high pressure sitting over the region, warm air is flowing further north than it normally would at this time of year.  It is also important to note that as our climate changes, record warm days are occurring more often and the autumn season as a whole is heating up.

Credit: The Weather Gamut

Autumn is Heating Up Across the US

Autumn is a transitional season. It is generally a time when the heat of summer fades away and the chill of winter gradually returns. But, as our climate changes, the season is heating up.

Across the contiguous United States, autumn temperatures have increased an average of 2.5°F over the past fifty years, according to Climate Central. The western part of the country has seen the fastest seasonal increase, with Reno, NV warming 7.7°F.  Las Vegas, NV, and El Paso, TX have each seen a rise of more than 5°F since 1970.

These warmer temperatures may feel like a summer bonus for some, but they also bring a number of negative impacts. Less frost-free days means the allergy season is extended and disease-carrying pests like mosquitos and ticks are able to live and thrive longer. Warmer temperatures also drive up energy bills, as people with air conditioning units use them longer into the season. This in turn, if they are powered by fossil fuels, adds even more heat-trapping greenhouse gases to the atmosphere.

Wildlife is also feeling the effects of a warming fall. The timing of when fruits ripen, for example, is being skewed from its “normal schedule”. In turn, this is impacting the once well-synced patterns of animal behaviors such as bird migration and hibernation.

Looking ahead, as greenhouse gas emissions continue to increase, so too will the temperature and its associated impacts.

Credit: Climate Central

Earth Posts 2nd Warmest August and 2nd Warmest June-August Season on Record

Our global temperature continued its upward trend last month. August 2019 marked not only Earth’s second warmest August, but also closed out the planet’s second warmest June-August season on record.

According to the State of the Climate Report by NOAA’s National Centers for Environmental Information, Earth’s combined average temperature for August – over both land and sea surfaces – was 61.76°F, which is 1.66°F above the 20th-century average. This August also marked the 416th 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.

The three-month period of June, July, and August – meteorological summer in the northern hemisphere – was also unusually warm. NOAA reports that Earth’s average temperature for the season was 1.67°F above the 20th century average of 60.1°F. That makes it the second warmest such period on record. It is also important to note that nine of the ten warmest June-August periods have all occurred since 2009.

While heat dominated most of the planet this August, some places were particularly warm, including Europe, Africa, and parts of Hawaii and Alaska. For the contiguous US as a whole, August 2019 tied August 1955 as the 13th warmest on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. As greenhouse gases continue to spew into the atmosphere, global temperatures are expected to continue to rise.

Year to date, the first eight months of 2019 were the third warmest such period of any year on record. At this point, it is very likely that 2019 will finish among the top five warmest years ever recorded. Global temperature records date back to 1880.

Credit: NOAA

Climate Indicator: Record Highs Outpacing Record Lows

There are a variety of indicators that show our climate is changing, including increasing average temperatures, melting glaciers, and sea-level rise. Nevertheless, it is extreme events, such as record heat, that usally garner the most attention.

Around the globe, the number of record high temperatures are out-numbering record low temperatures. In the US, according to an analysis by the AP, record warm days have out-paced record cold days by a ratio of 2:1 since 1999. This is a clear sign of our climate is shifting to a “new normal”.

In a stable climate, record highs and lows would be more balanced, with the ratio being closer to 1:1.

While climate change is a global phenomenon, we can see it playing out at a local scale. Here in New York City, we still get the occasional cold snap in winter, but the record highs have been outpacing the record lows for decades.

Credit: Climate Central

July 2019: Earth’s Warmest Month on Record

Our global temperature continued its upward trend last month with July 2019 marking not only the warmest July on record, but also the warmest month ever recorded for the entire planet. The previous record was set just three years ago in July 2016.

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 62.11°F. That is 1.71°F above the 20th-century average. Since July is the Earth’s warmest month of the year climatologically, the July 2019 global temperature is now the highest temperature for any month on record.

July 2019 also marked the 415th 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. Furthermore, nine of the ten warmest Julys have occurred since 2005, with the last five years producing the five warmest Julys on record. July 1998 is the only year from the last century on the top ten list.

While heat dominated most of the planet this July, some places were particularly warm, including Europe as well as parts of Asia, Africa, and Australia. In the United States, Alaska posted its warmest month ever recorded. For the contiguous US, the month tied July 1917 as the 27th warmest July on record.

These soaring temperatures are largely attributed to the long-term trend of human-caused climate change. As greenhouse gases continue to spew into the atmosphere, global temperatures are expected to continue to rise.

Year to date, the first seven months of 2019 tied 2017 as the second warmest such period of any year on record. At this point, it is very likely that 2019 will finish among the top five warmest years on record. Global temperature records date back to 1880.

July 2019 was the warmest month ever recorded on this planet. Credit: NOAA

July 2019: Tenth Hottest July on Record for NYC

July is usually the warmest month on the calendar for New York City, but this year it was especially hot. In fact, it tied July 1949 as the city’s tenth warmest July on record.

In all, it produced 26 days with above-average readings, including ten days in the 90s. Four of those days came during a heatwave in the middle of the month when the air temperature reached 95°F and the humidity made it feel well above 100°F.

Overnight lows were also mostly warmer than normal throughout the month. On July 20, the mercury only fell to 82°F, setting a new record warm low temperature for the date. In the end, the city’s mean temperature for the month was 79.6°F, which is 3.1°F above average.

It is important to note that four of the city’s ten warmest Julys on record have now occurred since 2010. The warmest was July 1999, when the average temperature for the month was 81.4°F.

This July was also above average in terms of precipitation. With several intense thunderstorms rolling through the area, a total of 5.77 inches of rain was measured in Central Park. The city, on average, gets 4.60 inches of rain for the month.

Credit: The Weather Gamut

First Heatwave of 2019 Brings Extreme Temperatures to NYC

A heatwave gripped a large swath of the eastern United States this weekend. For many areas, the temperatures were extreme.

The threshold for what constitutes a heatwave varies by region, but here in the northeast, it is defined as three consecutive days with temperatures reaching 90°F or higher. In New York City, the official temperature in Central Park reached 91°F on Friday, and 95°F on both Saturday and Sunday. Overnight lows were also well above average. In fact, on Saturday, the temperature only cooled down to 82°F, tying the record warm low termperature for the date that was set in 2015.

When the humidity was factored in, it felt even hotter. The heat index ranged from 105°F-110°F.

The city’s airports, LGA and JFK, both in the borough of Queens, posted record high temperatures over the weekend, according to the National Weather Service. JFK hit 99°F on Saturday, breaking the previous record of 96°F that was set in 2013. On Sunday, LGA reached the century mark (100°F), tying the high-temperature record for the date at the site that was set in 1991.

The cause of this exceptional heat was two-fold. First, a large area of high pressure sitting over the central US was pumping hot air from the southwest toward the northeast. At the same time, a strong Bermuda High off the east coast was pumping warm, moist air from the Gulf of Mexico into the region. Together, they made it dangerously hot, which is why the NWS issued an excessive heat warning for the city. It is also why several outdoor events around the Big Apple were canceled, including the NYC Triathlon.

The hottest day ever recorded in New York City occurred on July 9, 1936, when the air temperature hit 106°F in the shade. The city’s normal high temperature this time of year is 84°F.

A Tale of Two Highs: The Science Behind the Excessive Heat in the Northeast

Summer is the season for warm weather and even the occasional heatwave. But, the excessive heat that is gripping the eastern United States this weekend is exceptional. Its source is essentially a tale of highs – two areas of high pressure, that is.

The first is a Bermuda High. This is a large, semi-permanent, area of high pressure situated off the east coast. Spinning clockwise, it is strongest in the summer months and often steers hot, humid air from the Gulf of Mexico toward the northeast. It is usually the main cause of heatwaves in the region.

This current heatwave, however, is getting an extra boost from a second area of high pressure that is sitting over the central US. Also spinning clockwise, it is funneling hot air aloft from the southwest toward the northeast. Traveling eastward, this hot air must pass over the Appalachian Mountains, which run parallel to the eastern seaboard from Georgia to Maine. Following the topography downslope on the lee side of the mountains, the air compresses and warms even further. This is producing the exceptionally high air temperatures, such as the upper 90s and triple digits reported in cites across the region.

Combining this excessively hot air with the humidity being pumped into the area by the Bermuda High, the heat index or real feel temperatures are well above 100°F in many places.

This type of weather is more than just uncomfortable, it is dangerous. To avoid health complications, the American Red Cross recommends avoiding strenuous outdoor activity, drinking plenty of fluids, and cooling off in air-conditioned spaces when possible.

Credit: NOAA/NWS

Extreme Heat Can Pose a Danger to Your Health

A heat emergency has been issued for New York City.  As temperatures soar, it is important to remember that intense heat can cause serious health problems.

According to the CDC, extreme heat – temperatures that are significantly hotter than the average local summertime high – is one of the leading causes of weather-related deaths in this country. Claiming hundreds of lives every year, excessive heat kills more people across the U.S. than hurricanes and tornadoes combined.

Extreme heat is deadly because it forces the human body beyond its capacity to cool itself. Linked to overheating and dehydration, heat-related illnesses can range in severity from mild to life-threatening.  Symptoms for each stage include:

Heat Cramps:  Painful muscle spasms in the legs and/or abdomen

Heat Exhaustion:  fatigue, weakness, clammy skin, and nausea

Heat Stroke:  rapid pulse, hot and dry skin, no sweating. This is a medical emergency

To beat the heat, the American Red Cross suggests:

  • Avoid strenuous activity
  • Dress lightly
  • Eat lightly
  • Drink plenty of water
  • Replenish salts and minerals lost through perspiration with sport-drinks
  • Limit caffeine and alcohol
  • Stay out of the sun
  • Cool off in an air-conditioned building, when possible

Credit: NWS/WRN