April Feed

Spring Awakening - The Year's First High Temperature in the 70s

70+

 

So far this century, the average date for the first reading of 70° or warmer in Central Park has been March 19 (and in the past five years it's been March 5).  This is four weeks earlier than what the average date was during 1869-1899; and during the 20th century this first occurrence was at the end of March.  The earliest date for a 70+ reading has been Jan. 6, which happened in 2007 (joining two other "first 70s" in January, in 1932 and 1950); the latest date is May 9, which happened in 1875 (and it's happened in May in five other years, the last time being in 1940).

 

Chart - earliest first 70s

Chart - latest first 70

 

The average high temperature on the day of the first 70+ has been 74°; the average low on that day, 48° (this diurnal variation of 24 degrees is much wider than the typical daily variation of 15 degrees).  The average high of the day before the first 70+ is 60°; the average high on the day following the first 70+ day  is 66°. 

 

11 years' first 70+ reading also served as those years' first 80°+ reading, with the most recent occurrence being in 2003.  And in 1927 the year's first 70+ served not only as the first 80+, but as the year's first reading in the 90s.  Meanwhile 15 other years had their first 80+ come the day after the first 70+ (the last time this happened was in 2013).

 Chart - warmest first 70s

 

Back-to-back years with very early dates for the first 70+ are 1949 (Feb. 15) and 1950 (Jan. 26), and 2017 (Feb. 21) and 2018 (Feb. 24).  And there have been two periods of three consecutive years with very late dates: 1883 (May 3), 1884 (May 2) and 1885 (April 21); and 1875 (May 9), 1876 (May 6) and 1877 (April 23).

 

The greatest difference in high temperature between the day before and the day of the first 70+ is +34 degrees, in March 1935 (from 43° to 77°), and +33 degrees in April 2001 (from 45° to 78°).  And the biggest decline on the day after occurred in March 1934, -35 degrees (from 71° to 36°), and -34 degrees in Feb. 1874 (from 72° to 38°).  Lastly, the biggest increase on the day after is +14 degrees in 1902 (from 70° to 84°).

 

Chart - biggest temp diff day before first 70

 Chart - biggest temp drop after first 70

The greatest diurnal variation on the day of the first 70+ is 42 degrees, with a high/low on March 13, 1990 of 85°/43°.  The coldest reading to occur on the day of the first reading of 70+ is 30° on March 18, 1934.  It came after the high of 71° was reached and a cold front moved thru mid-afternoon.  (This is the also the only time a reading of 32° or colder occurred on the same day as the first 70°+.)

 

After a reading of 70°+, the average number of days before the next reading of 70°+ has been 11, with the greatest hiatus being 80 days in 1932 (when the first 70+ was on 1/14).  Not surprisingly, the most days to elapse before the next 70+ high have occurred in Jan/Feb -  with the average hiatus being 43 days.  In about one-third of the years the first 70°+ was followed the very next day by another high of 70+, with the longest streak being eight days, in April 1896 (including highs of 87°, 88° and 90°).  The longest streak in the years since 1900 has been six, set in April 1952.  

 

Spring awakening
 

 

An early first 70+ isn't predictive of a hot summer as some very hot summers had their first 70+ at a late date.  This includes the year with the second hottest summer, 1966, which didn't see its first 70+ until April 25.  And the fifth and sixth hottest summers, in 1983 and 1993, didn't have their first 70+ until April 25 and April 19, respectively.

 

About 20% of the dates of the first 70+ reported measurable rain; two-thirds of these years had amounts less than 0.10".  (By contrast, 40% of the days with the first 60+ reading had rain.)  Just one date had more than an inch, on April 6, 1937.  On that day, 1.02" of rain fell before dawn and ushered in mild air (the high reached 72°).

 

And, finally, some more interesting occurrences:

> In 2018, after a high of 78° on Feb. 21 (the warmest reading ever in Jan/Feb), more than seven weeks passed before the mercury rose above the low 60s.

> In 1998 the first 70+ reading was 83° and it was the first of five days in a row in the 80s - at the end of March (March 27-31), when the average high is in the mid-50s. 

> The first high of 70+ in 1988, 76° on 3/24, came just two days after a low of 17°

> The day of 1980's first 70+ followed a big rainstorm of 3.42" the day before.

> In 1967, a week after the first 70+, on March 11, there was a week of harsh winter conditions, with an average high/low of only 31°/20°, including a reading of 8° on 3/19; and three snowfalls produced 15.4" of snow. 

> 1947's first 70+ on 4/6 was the day after nearly two inches of rain fell. 

> In 1929 the first 70+ came three days after a low of 12°.  (In 2009 a low of 12° in March came four days before the year's first 70+.)

> In 1874, two days after a high of 72° on Feb. 23, 7.5" of snow fell. 

 

Springtime in central park

 

To read an analysis about the first readings of 60+ each year, double click here.

 

 

 


April 2020 Weather Review: First Cooler Than Average Month of the Year

April 2020

 

April was 2.7 degrees below average, making it the first month this year to be chillier than average.  It was also the fourth chilliest April of the past 40 years.  Even more interesting, this was the first April since 1940 with no highs of 70° or warmer (after three such days in March).  In the years since 2000 the warmest reading in April has averaged 85°, but this April's mildest reading was just 68° .  Despite this cool warmest reading, the nights weren't as cold as might be expected as the coldest reading, 36°, was three degrees milder than a typical April's coldest temperature.  The 32-degree difference between the month's coldest and warmest readings was 20 degrees less than the average difference between the two extremes - the smallest gap of any April on record.

 

The last sixteen days of the month all had below average mean temperatures, the longest below average streak since March 2018's streak of 22 days.  These 16 days were seven degrees below average (seven of the days were ten or more degrees below average).  Before this streak started April had been two degrees milder than average (with April 4-8 seven above average).

 

Although it was the fourth coldest April of the past 40 years, it ranked 63rd among all Aprils going back to 1869.  This was due to the fact that Aprils before 1940 were much chillier.

 

Cool-ish

 

Although April's rainfall, at 4.49", was an average amount, it was enough to make it the rainiest month so far this year.  The month also had the year's biggest rainstorm - 1.92" on 4/13 (the day after Easter).

 

A typical April is 10 to 11 degrees warmer than March, but April 2020 was just 2.4 degrees milder - the third closest of any year.  Additionally, April's mildest reading was nine degrees cooler than March's (68° vs. 77°) and its mildest low temperature was one degree cooler than March's (53° vs. 54°).

 

Chart - closest april-march temp
 

2020 is just the seventh year in which April, March and February had more precipitation than the month preceding it. This year April had 4.49"; March, 3.78"; February 2.54"; and January 1.93".

Chart - first 4 months of rain

 

Here are April recaps of previous years:

2019

2018

2017

2016

 

     


April 2019 Weather Recap

April 2019As we headed into the last week of April it appeared the month had a good chance of becoming either the fifth, sixth or seventh mildest April on record.  But when the last five days of the month averaged five degrees cooler than average, it ended up as the 13th mildest, 2.5 degrees above average (still a noteworthy achievement as it was milder than 138 other Aprils).  Perhaps a bigger highlight was the month's 18 days with measurable precipitation, the most since May 2012.  This was also the most days of precipitation of any April.  However, despite the frequent rainfall, the 4.55" that was measured was just an average amount.  Despite being only average, this amount was enough to make April the wettest month so far this year. 

 

The five chilly days at the end of the month were immediately preceded by a two-week period with above average temperatures (six degrees above average); this was the longest streak of above average days since one of eighteen days in late December/early January.  This mild streak included the year's first reading in the 80s - 80° on 4/19, which was Good Friday (just the fifth Good Friday with a high in the 80s); Easter Sunday cooled down to a high of 66°.  The month's coldest reading, 33°, occurred on 4/1.  (Since 2000 April's warmest temperature has averaged 85°, its coldest reading has averaged 33°.)

 

Finally, 2019's mild April came a year after the coldest April in 40 years (which followed the second mildest April on record).  Despite the disparity between the two years, April 2018's warmest temperature was two degrees above this year's (82° vs. 80°) while its coldest reading was just one degree lower (32°).

 

W4th street blossoms

Here are recaps of previous Aprils:

2018

2017

2016

 


Best & Worst Weather Conditions During Mets Home Openers

Mr. metIt seems fitting that the Mets first home opener in 1962, a season in which they lost 120 games, ranks as one of its worst, with cold temperatures, wind and drizzle.  And how perfect was it that the weather was glorious the year they won their first home opener in 1968?  The charts below focus on the best weather conditions in years the Mets won their home openers, while the worst weather is grouped into games lost and games won.  (But does it really matter what the weather is, just as long as the home team wins?)      

 

 Chart - best and worst mets home openers

 

To read about weather and outcome of every Mets home opener since 1962, double click here.

 

Tom seaver

 

 


April 2018 Weather Recap - Chilly, Snowy, Rainy

Rainy day in new yorkLike four of the past five months, April was colder than average.  (February, the mildest on record, was the outlier.)  This was the chilliest April since 1975, 3.5 degrees below average.  Eight days had mean temperatures ten degrees or more colder than average (and half of the month's days were five degrees or more below average).  Just three days had highs of 70°+, the fewest since April 2000.  Two of them were back-to-back: 82° and 77° on 4/13 and 4/14.  Earlier that week the month's coldest temperature, 32°, was posted on consecutive days, on-par with what the coldest reading is during a typical April (33°).  However, the number of days with highs chillier than 50° (nine) and lows in the 30s (sixteen) was well above average (three and five days, respectively). 

 

April was also a wet month, with 5.78" of precipitation measured, making it the third month in a row to receive more than five inches (5.83" fell in February, 5.17" in March).  The last time this occurred was August-October 2011.  More than half of the month's precipitation fell during a rainstorm on 4/15-16 that dropped 3.29", the biggest deluge since April 30, 2014.  Finally, Easter, which fell on 4/1, was sunny and pleasant, with a high of 60°.  However, 5.5" of snow fell the next morning (forcing postponement of the Yankees' home opener).  This was the biggest snowfall in April since 1982.

 

Snow on yankees home opener

 

April 2018 was just one of three Aprils since 1970 to have an average temperature below 50.0 degrees (coming in at 49.5 degrees).  Before 1970, however, April temperatures this cool were much more common, with half of the Aprils between 1869 and 1969 being that chilly.  Therefore, when compared to all Aprils, this April ranks as 44th coolest overall.  Finally, March and April 2018 combined were the coldest first two months of meteorological spring since 1984, and the third coldest in the years since 1970.

 

For recaps of the past two Aprils double-click here: April 2017 and April 2016 

 

 Apr 22 st lukes garden

 

 

 

 

 


April 2017 Recap: Second Mildest April, Featuring Second Warmest Easter

BlossomsWith four days in the 80s and no truly cold days (the chilliest was five degrees below average), April 2017 became the second mildest April on record (4.2 degrees above average), pushing April 1941 to third place (57.2° vs 56.9°).  This was a rebound from March, which was 3.3 degrees colder than average.  April's coldest low was 37° on 4/1, which was only three degrees colder than average.  This was the "mildest coldest" reading since April 2010 (the mildest April on record).  The warmest reading of the month, 87°, occurred on Easter Sunday (4/16), which was the second warmest temperature every experienced during the holiday. 

 

 

Interestingly, despite it being the second mildest overall, eight other Aprils had warmer average highs than April 2017.  However, this April was the mildest of them all in terms of average low, even ahead of New York's mildest April (2010) by a comfortable margin.

 

10 Mildest Aprils

 

Other observations of interest:

  • The four 80-degree days were the most since April 2009, when there were also four (the most for any April is five, which happened in four years:  2002, 1985, 1962 and 1941).  This years summery high temperatures occurred on 4/11 (80°), 4/16 (87°), 4/28 (85°) and 4/29 (85°).

 

80degrees

 

  • Although there were two days in the mid-80s at the end of April, the most extended period of above average temperatures occurred from 4/10 thru 4/17 when temperatures were 13 degrees above average.
  • Although Easter Sunday had the warmest high temperature, the day with the warmest mean temperature (average of the high and low) was 4/29, which had a high/low of 85/64, 1.5 degrees degrees warmer than Easter (87/59).
  • The month's two biggest rainstorms produced nearly identical amounts - 1.21" in the pre-dawn hours of 4/4, and 1.25" on the night of 4/25 into the early AM hours of the 26th.
  • Finally, for what it's worth, the warmest and coldest readings of April 2005 were the same as April 2017 (87/37), but 2015 is ranked as 14th mildest.

 

Springtime sky on west fourth st 

 

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save

Save


April 2016 Weather Recap - Dry, With Average Temperatures

April2016The dry conditions of March (1.17") continued through April (1.61"), but unlike March, which was the fourth mildest on record, April was just about average (+0.3 degrees).  March's warmth, however, extended into April for one day when the high/low was 79/61 on 4/1 (22 degrees above average).  But just four days later the temperature plunged to 26°, which was the coldest reading in April since 1995.  This came in the midst of an eight-day stretch (through 4/10) that saw temperatures that were eight degrees below average.  Temperatures then rebounded for the week between 4/17-23 as highs averaged 75°, twelve degrees above average.  But the month ended on a cool note, with the last five days 3.5 degrees below average.  Some other observations worth noting:

 

  • The highlight of the month was the eleven-day stretch from April 12-22 which had sunny or clear skies every day and extremely low humidity.  Afternoon humidity levels in April are typically in the 40-50% range, but on these days it was mostly between 15-20%.  And on 4/20 at at 6PM it dropped to 9% - the lowest since a reading of 6% on March 30, 2007.
  • March and April were the first back-to-back months with less than two inches of rain since the winter of 2012 - and the driest March-April combination on record (the previous driest was way back in 1885).  The combined 2.78" for these months was one-third the average amount of 8.86".  March was the sixth driest on record, April the eleventh driest.
  • Despite the dry conditions of April, nine of the first twelve days of the month had rain.  The rainiest of the days, 4/4 (when 0.49" fell), occurred the day of the Yankees' home opener, which was postponed.  
  • For the second year in a row the year's first 80-degree reading occurred on 4/18.  This was five days earlier than average
  • Finally, although it had nothing to do with April's weather, on 4/28 the National Weather Service announced that it had revised the accumulation of the big blizzard of 1/23 upward by 0.7", to 27.5".  This new total pushed it ahead of the blizzard of Feb. 2006 (26.9"), making it York's biggest snowstorm on record.  The accumulation that was added had fallen after midnight on 1/24 but had been overlooked.

 

Treeblossoms

 

 

 

Save


When April Isn't Much Warmer Than March

Two.arrows.pointingateachotherThe month of April is typically 10.5 degrees milder than the month of March.  April 2020, however, was just 2.4 degrees milder, making its average temper the third closest to March of any April (going back to 1869).  The closest April came to March was in 1946 when April was 0.8 degrees milder than March.  The chart below lists the six Aprils that were closest to March's average temperature.

 

Chart - closest april-march temp

And although April 2020 wasn't chillier than March, it had no days in the 70s while March had three (making this the first April since 1940 not to have any readings of 70° or warmer).

 


 

 

 

Save


April Ends with a BIG Splash

April30.rainstormNo month has ever ended with such a big rainstorm as did April 2014.  4.97" poured down on April 30, making it New York's rainiest day on record.  Previous to this, the rainiest day at the end of a month end occurred on Aug. 31, 1911 when 3.76" fell.  Before April 30's deluge the month had been an inch-and-a-half below average.  It ended up becoming the sixth rainiest April on record. 

 

April.showersMore than 60% of the month's rainfall was accounted for on the last day of the month.  What also made this day's rainfall of interest was that up until this year April 30 was one of three days in which an inch or more of rain had never fallen (the other two days are April 29 and Sept. 9). 

 

And the wettest first day of any month?  That honor goes to Oct. 1, 1913 when 4.98" fell (yes, 0.01" more than April 30, 2014).  

 

RAINIEST ENDS TO A MONTH
     
    % of Month's
Date Amount Total Precip
April 30.2014 4.97" 63%
Aug 31,1911 3.76" 41%
May 31,1940 3.13" 41%
June 30, 1984 3.07" 53%
Oct 31,1956 2.41" 67%
Dec 31,1948 2.31" 37%
July 31, 1889 2.29" 19%
Feb 29,1896 2.26" 33%
Sept 30,1921 2.21" 46%
July 31,1925 2.14" 37%
     
RAINIEST STARTS TO A MONTH
     
Oct 1, 1913 4.98" 38%
Sept 1, 1927 3.84" 90%
Sept 1, 1983 3.40" 74%
Mar 1, 1914 2.95" 62%
Aug 1,1878 2.85" 36%
June 1,1887 2.60" 34%
May 1  1976 2.48" 52%
Oct 1, 2010 2.46" 50%
July 1,1933 2.17" 36%
July 1, 1922 2.13" 28%
     

(Many thanks to my friend Eugene DeMarco for creating a spreadsheet that listed every one-inch rainfall in NYC since 1869. It made doing this analysis possible.) 

 

 


Today in New York Weather History: April 14

 

1880

Today's high of 80° came just two days after a record low of 26° (since eclipsed in 1976).  This was the first reading above 64° since 3/5 (when it was 72°).

1940

A trace of snow was reported for the 33rd time this snow season, the most ever (later tied in 1944-45).  Today's high/low was 41°/30°.

 

Trace

1966

This was the fourth day in a row with a low of 39° (five degrees below average).  However, all of the days had different highs, with three in the 57°-60° range and one with a high of only 44°. 

1979

It was a rainy and chilly Easter Saturday.  1.10" of rain fell (ending late in the afternoon) and the high/low was 45°/40°; the high was nearly twenty degrees below average. 

2014

This was the fourth day in a row with highs in the 70s.  The average high during these days was 75°, fifteen degrees above average.

 

Clipart_sun_with_glasses

2018

After the temperature peaked at 77° in the middle of the afternoon a back-door cold front moved through and by midnight the temperature had fallen to 44°.  This was the greatest drop in temperature since 1/13, when it plummeted from 58° to 19°.  (It was also the second biggest drop in more than four years.)

Save

Save