donsutherland1

Tomorrow will be mostly cloudy with some showers, along with cooler temperatures. Following passage of the warm front, Thursday and Friday will be much warmer. Highs in the region will reach the upper 60s and lower 70s Thursday and lower to middle 70s with some upper 70s on Friday. Some showers and even thundershowers are possible, especially on Friday. A sustained period of above to much above normal temperatures is now underway. In general, above normal temperatures will persist through the end of March. Any cool shots will likely be modest and brief. Some of the guidance suggests that a cold shot and at least some snow could affect northern New England near the end of March. The ENSO Region 1+2 anomaly was +0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around March 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.77°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was +5.41 today. The preliminary Arctic Oscillation (AO) figure was +3.596 today. The 31° temperature recorded at Central Park on March 19 was likely New York City's last freeze of 2020-21 based on a combination of the latest ensemble guidance and the diminishing frequency of April freezes. April freezes have become less frequent in recent years. During the 1991-2020 base period, there were 12 cases where the last freeze occurred in April. The last time the temperature fell to freezing in April occurred in 2018. Select April Statistics: 1951-80: Years with freezes: 17; Mean days with lows of 32° or below: 1.1 1961-90: Years with freezes: 17; Mean days with lows of 32° or below: 1.3 1971-00: Years with freezes: 16; Mean days with lows of 32° or below: 1.2 1981-10: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 1991-20: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 Least years with freezes: 10, 1984-2013 Most years with freezes: 26, 1874-1903, 1880-1909, 1895-1924, 1896-1925, and 1897-1926 Lowest number of average days with temperatures of 32° or below: 0.8, 1983-2012, 1984-2013, 1985-2014, and 1986-2015 Highest number of average days with temperatures of 32° or below: 3.7, 1871-1900 and 1872-1901 Least days in April with temperatures of 32°: 0, Most Recent: 2020 Most days in April with temperatures of 32°: 11, Most Recent: 1874 Based on sensitivity analysis applied to the latest guidance, there is an implied 95% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.6° (2.1° above normal).

Much of the City is now tainted by the urban heat island effect. Parts of the northern Bronx and also Staten Island are less severely impacted. Central Park could be improved with some commitment to greater accuracy there. That would entail managing the tree growth around the station, measuring snowfall when the snow stops falling, etc. The issue of trees has a larger impact on temperatures.

The City radiates poorly. I had thick frost the past two days (not today), as well.

Morning thoughts... Morning fog will burn off and give way to a partly sunny day. Clouds could become more noticeable during the afternoon or evening. High temperatures will likely reach the lower 60s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 63° Newark: 63° Philadelphia: 66° Tomorrow will be mainly cloudy and cooler with some showers. Much warmer air will arrive for Thursday and Friday.

Temperatures rose into the upper 50s to lower 60s across the region this afternoon after a frosty start outside the big cities. Tomorrow will be another mainly sunny and springlike day. Afterward, Wednesday will be mostly cloudy with some showers, along with cooler temperatures. Much above normal temperatures are likely on Thursday and Friday. In addition, some showers and possibly thundershowers are possible. A sustained period of above to much above normal temperatures is now underway. In general, above normal temperatures will persist through the end of March. Any cool shots will likely be modest and brief. Newfoundland and Labrador saw a number of record high temperatures. High temperatures included: Churchill Falls: 52° (old record: 45°, 2012) Goose Bay: 53° (old record: 51°, 2000) Hopedale: 42° (old record: 40°, 1946) Mary's Harbour: 55° (old record: 42°, 2000) There remains some potential for another day of near record to record warm temperatures in eastern Canada tomorrow. The ENSO Region 1+2 anomaly was +0.5°C and the Region 3.4 anomaly was -0.5°C for the week centered around March 17. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.08°C and the ENSO Region 3.4 anomaly has averaged -0.77°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was +9.81 today. The preliminary Arctic Oscillation (AO) figure was +3.609 today. The 31° temperature recorded at Central Park on March 19 was likely New York City's last freeze of 2020-21 based on a combination of the latest ensemble guidance and the diminishing frequency of April freezes. April freezes have become less frequent in recent years. During the 1991-2020 base period, there were 12 cases where the last freeze occurred in April. The last time the temperature fell to freezing in April occurred in 2018. Select April Statistics: 1951-80: Years with freezes: 17; Mean days with lows of 32° or below: 1.1 1961-90: Years with freezes: 17; Mean days with lows of 32° or below: 1.3 1971-00: Years with freezes: 16; Mean days with lows of 32° or below: 1.2 1981-10: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 1991-20: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 Least years with freezes: 10, 1984-2013 Most years with freezes: 26, 1874-1903, 1880-1909, 1895-1924, 1896-1925, and 1897-1926 Lowest number of average days with temperatures of 32° or below: 0.8, 1983-2012, 1984-2013, 1985-2014, and 1986-2015 Highest number of average days with temperatures of 32° or below: 3.7, 1871-1900 and 1872-1901 Least days in April with temperatures of 32°: 0, Most Recent: 2020 Most days in April with temperatures of 32°: 11, Most Recent: 1874 Based on sensitivity analysis applied to the latest guidance, there is an implied 93% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.6° (2.1° above normal).

Tornado study: https://www.pnas.org/content/118/14/e2021535118

Morning thoughts... At 7 am, temperatures in New York City, Newark and Philadelphia ranged from the middle 30s to lower 40s. Outside the cities, temperatures were in the upper 20s and lower 30s where a thick frost was present. Temperatures included: Allentown: 27°; Bridgeport: 33°; Danbury: 28°; Islip: 31°; New York City: 43°; Newark: 37°; Philadelphia: 35°; Poughkeepsie: 27°; Trenton: 31°; Westhampton: 26°; and, White Plains: 31° Under bright sunshine, temperatures will rebound strongly. High temperatures will likely reach the upper 50s and lower 60s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 62° Newark: 62° Philadelphia: 64° Tomorrow will be mainly fair and continued mild. Late in the week, there could be some showers and thundershowers, along with unseasonably warm readings.

Hopefully, at some point, that area will be cleaned and converted into a park with playing fields, a track or walking trail, among other options if it is the site I believe it is.

Today the temperature rose into the lower and even middle 60s across much of the region. As a result, New York City's monthly temperature departure has now moved above the normal figure through March 21. A sustained period of above to much above normal temperatures is now underway. In general, above normal temperatures will persist through the end of March. Any cool shots will likely be modest and brief. Tomorrow will be partly to mostly sunny and continued mild. It will be a little cooler than today. Up north, there is potential for near record to record warm temperatures in eastern Canada tomorrow and Tuesday. The ENSO Region 1+2 anomaly was +0.9°C and the Region 3.4 anomaly was -0.3°C for the week centered around March 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.20°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was +8.85 today. The preliminary Arctic Oscillation (AO) figure was +3.288 today. The 31° temperature recorded at Central Park on March 19 could be New York City's last freeze of 2020-21 based on a combination of the latest ensemble guidance and the diminishing frequency of April freezes. April freezes have become less frequent in recent years. During the 1991-2020 base period, there were 12 cases where the last freeze occurred in April. The last time the temperature fell to freezing in April occurred in 2018. Select April Statistics: 1951-80: Years with freezes: 17; Mean days with lows of 32° or below: 1.1 1961-90: Years with freezes: 17; Mean days with lows of 32° or below: 1.3 1971-00: Years with freezes: 16; Mean days with lows of 32° or below: 1.2 1981-10: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 1991-20: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 Least years with freezes: 10, 1984-2013 Most years with freezes: 26, 1874-1903, 1880-1909, 1895-1924, 1896-1925, and 1897-1926 Lowest number of average days with temperatures of 32° or below: 0.8, 1983-2012, 1984-2013, 1985-2014, and 1986-2015 Highest number of average days with temperatures of 32° or below: 3.7, 1871-1900 and 1872-1901 Least days in April with temperatures of 32°: 0, Most Recent: 2020 Most days in April with temperatures of 32°: 11, Most Recent: 1874 Based on sensitivity analysis applied to the latest guidance, there is an implied 92% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.6° (2.1° above normal).

There are a few high clouds in the East in southern Westchester County.

Under brilliant sunshine and a cloudless sky, the temperature soared into the lower 60s in New York City. The New York Botanical Garden has taken on an increasingly springlike appearance. It won’t be too much longer before the cherry trees begin to bloom.

Compared to even a decade ago, an increasing share of TV weather has essentially become little more than “fast food” of weather, though there remain exceptions. On many stations, it is no longer substantive (details and time spent discussing weather developments have decreased even as the impact of weather has not). On air expertise is sometimes superficial. One sees fewer degreed meteorologists involved. Likely, on account of fewer degreed meteorologists being involved, when it comes to discussions of such things a precipitation type issues, one never sees the deployment of even a single sounding chart to illustrate what is going on aloft. Hence, an avoidable public misperception that it is ‘cold enough’ for snow persists even when there is too much warm air aloft. This is an unfortunate situation. I always advise my friends and co-workers to follow the National Weather Service if they really want a forecast they can rely on. I continue to be impressed by the dedication and expertise possessed by those within the region (ALY, BOX, OKX, and PHI).

Morning thoughts... Under bright sunshine, today will feature springlike warmth. High temperatures will reach the lower 60s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 63° Newark: 64° Philadelphia: 64° Tomorrow will be continued fair and a little cooler. Late in the week, there could be some showers and thundershowers, along with unseasonably warm readings.

JFK and NYC got to 34 on May 9. That was Central Park’s coldest temperature so late in the year.

There was a severe weather outbreak on the 17th.

It’s the outgoing GFS leaving one last memory of its cold and excessive snowfall biases.

A sustained period of above to much above normal temperatures is now developing. Tomorrow will again be fair and mild. In general, above normal temperatures will persist through the end of March. There is potential for near record to record warm conditions to occur in eastern Canada on Monday and Tuesday. The ENSO Region 1+2 anomaly was +0.9°C and the Region 3.4 anomaly was -0.3°C for the week centered around March 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.20°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was +5.79 today. The preliminary Arctic Oscillation (AO) figure was +1.469 today. The 31° temperature recorded at Central Park on March 19 could be New York City's last freeze of 2020-21 based on a combination of the latest ensemble guidance and the diminishing frequency of April freezes. April freezes have become less frequent in recent years. During the 1991-2020 base period, there were 12 cases where the last freeze occurred in April. The last time the temperature fell to freezing in April occurred in 2018. Select April Statistics: 1951-80: Years with freezes: 17; Mean days with lows of 32° or below: 1.1 1961-90: Years with freezes: 17; Mean days with lows of 32° or below: 1.3 1971-00: Years with freezes: 16; Mean days with lows of 32° or below: 1.2 1981-10: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 1991-20: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 Least years with freezes: 10, 1984-2013 Most years with freezes: 26, 1874-1903, 1880-1909, 1895-1924, 1896-1925, and 1897-1926 Lowest number of average days with temperatures of 32° or below: 0.8, 1983-2012, 1984-2013, 1985-2014, and 1986-2015 Highest number of average days with temperatures of 32° or below: 3.7, 1871-1900 and 1872-1901 Least days in April with temperatures of 32°: 0, Most Recent: 2020 Least days in April with temperatures of 32°: 11, Most Recent: 1874 Based on sensitivity analysis applied to the latest guidance, there is an implied 87% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.4° (1.9° above normal).

Morning thoughts... The low temperature at Central Park was 33° this morning. As a result, yesterday’s 31° figure was likely New York City’s last freeze of 2020-21, based both on the latest ensemble guidance and diminishing frequency of April freezes. Under bright sunshine, today will feature a springlike afternoon. High temperatures will reach the middle and upper 50s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 57° Newark: 59° Philadelphia: 59° Tomorrow will be continued fair and mild.

Earlier today, the temperature fell to 31° in New York City. Overnight, the temperature could again approach or reach freezing in Central Park. Afterward, it is possible that New York City will not see the temperature fall to freezing until some time next fall, as the remainder of March will likely see above freezing temperatures. April freezes have become less frequent in recent years. During the 1991-2020 base period, there were 12 cases where the last freeze occurred in April. The last time the temperature fell to freezing in April occurred in 2018. Select April Statistics: 1951-80: Years with freezes: 17; Mean days with lows of 32° or below: 1.1 1961-90: Years with freezes: 17; Mean days with lows of 32° or below: 1.3 1971-00: Years with freezes: 16; Mean days with lows of 32° or below: 1.2 1981-10: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 1991-20: Years with freezes: 12; Mean days with lows of 32° or below: 1.0 Least years with freezes: 10, 1984-2013 Most years with freezes: 26, 1874-1903, 1880-1909, 1895-1924, 1896-1925, and 1897-1926 Lowest number of average days with temperatures of 32° or below: 0.8, 1983-2012, 1984-2013, 1985-2014, and 1986-2015 Highest number of average days with temperatures of 32° or below: 3.7, 1871-1900 and 1872-1901 Least days in April with temperatures of 32°: 0, Most Recent: 2020 Least days in April with temperatures of 32°: 11, Most Recent: 1874 The coming weekend will mark the start of a warming trend. Since 1950, nearly 60% of days two weeks after the AO reached +3.000 or above in the March 1-15 period were warmer than when the AO reached +3.000 or above. The AO reached +3.000 on March 10. The mean increase was 2.8°. This suggests that it is more likely than not that the closing week of March could see a return to warmer conditions. Most of the guidance favors the development of warmer conditions that would continue through the remainder of the month. There is potential for near record to record warm conditions to occur in eastern Canada early next week. The ENSO Region 1+2 anomaly was +0.9°C and the Region 3.4 anomaly was -0.3°C for the week centered around March 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.20°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -2.20 today. The preliminary Arctic Oscillation (AO) figure was +0.238 today. Based on sensitivity analysis applied to the latest guidance, there is an implied 85% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.3° (1.8° above normal).

Morning thoughts... Following a departing storm that ended with a little light snow in the New York City region, today will be partly cloudy and windy. It will be unseasonably chilly. High temperatures will reach the lower and middle 40s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 44° Newark: 45° Philadelphia: 47° A pronounced warming trend will likely commence during the weekend. As a result, should the temperature fall to freezing tomorrow morning, there is a chance that it could be Central Park’s last freeze of the 2020-21 season. Early next week could see near record to record warmth in parts of eastern Canada. Finally, it is likely that Central Park will fall short of receiving the 1.4” snow needed to reach 40.0” for winter 2020-21. Since 1869, there were 30 cases that saw no measurable snowfall during March 1-19. Mean snowfall for the remainder of the snow season came to 0.8”. 60% of cases saw no measurable snowfall, 77% of cases saw less than 1” of snow, 23% saw 1” or more snow, and 17% saw 2” or more snow during the remainder of the snow season. The most snowfall from such cases was 5.0” during 1998. The most recent such case occurred in 2020 when no measurable snow was reported after March 19.

Colder air will press southward tonight. As the temperature falls, rain will change to snow in parts of the Northeast. Precipitation will likely total 0.50" - 1.50" from Philadelphia to Boston with some higher amounts. There could still be an area of 1"-3" snowfall with some locally higher amounts in an area running through New England, that could include Boston and/or Worcester. There is a chance that the rain could end as a period of snow or flurries even in New York City and its nearby suburbs. The coming weekend will likely mark the start of a warming trend. Since 1950, nearly 60% of days two weeks after the AO reached +3.000 or above in the March 1-15 period were warmer than when the AO reached +3.000 or above. The AO reached +3.000 on March 10. The mean increase was 2.8°. This suggests that it is more likely than not that the closing week of March could see a return to warmer conditions. Most of the guidance favors the development of warmer conditions that would continue through the remainder of the month. The ENSO Region 1+2 anomaly was +0.9°C and the Region 3.4 anomaly was -0.3°C for the week centered around March 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.20°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -2.49 today. The preliminary Arctic Oscillation (AO) figure was -0.117 today. On March 17 the MJO data was unavailable. MJO data will no longer be posted until the data is again available. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 28.1" snow. Winters that saw December receive 10" or more snow, less than 10" in January, and then 10" or more in February in New York City, saw measurable snowfall in March or April in 83% of cases. Winter 2009-2010 was the exception where only a trace of snow was recorded. This group of winters saw 6" or more snow during the March-April period in 50% of the cases. All said, it is more likely than not that there will be measurable snowfall after February. Based on sensitivity analysis applied to the latest guidance, there is an implied 81% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 44.0° (1.5° above normal).

It’s too soon for me to make any calls about snowfall for April. I do think this will be the last chance for snowfall in March given the forecast pattern and strong consensus on the guidance about warmer conditions for the remainder of the month beginning Sunday.

Morning thoughts... Tornadoes, large hail, and damaging winds pounded parts of the Gulf Region yesterday. Today, the focus of the severe weather will stretch from Georgia, across the Carolinas, and into Virginia before moving offshore. At 7:50 am, an area of rain was advancing into eastern Pennsylvania and southern New Jersey. Rain will develop this morning in most of the region. Precipitation will likely total 0.50”-1.50” from Philadelphia to Boston with some locally higher amounts in excess of 2.00”. High temperatures will reach the upper 40s and lower 50s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 50° Newark: 50° Philadelphia: 52° As colder air presses southward tonight, rain will change to snow across central New York State and central New England. That snow will push southward. There will be an area of 2”-4” snowfall with locally higher amounts in parts of New England, including Boston and Worcester. The rain could end as a period of snow or flurries even in New York City and its nearby suburbs. A pronounced warming trend will likely commence during the weekend. As a result, there is a chance that the coming weekend could see Central Park’s last freeze of the 2020-21 season.

Tomorrow will be rainy, as a developing storm moves eastward and then offshore tomorrow night. As colder air pushes in, rain will change to snow in parts of the Northeast. There will likely be an area of 2"-4" snowfall with some local amounts of 6" over in an area running through New England, including Boston and Worcester. There is a chance that the rain could end as a period of snow or flurries even in New York City and its nearby suburbs. The coming weekend will likely mark the start of a warming trend. Since 1950, nearly 60% of days two weeks after the AO reached +3.000 or above in the March 1-15 period were warmer than when the AO reached +3.000 or above. The AO reached +3.000 on March 10. The mean increase was 2.8°. This suggests that it is more likely than not that the closing week of March could see a return to warmer conditions. Most of the guidance favors the development of warmer conditions that would continue through the remainder of the month. The ENSO Region 1+2 anomaly was +0.9°C and the Region 3.4 anomaly was -0.3°C for the week centered around March 10. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.20°C and the ENSO Region 3.4 anomaly has averaged -0.80°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -2.68 today. The preliminary Arctic Oscillation (AO) figure was -0.288 today. The AO's 5-day change from its March 12 peak of +5.656 is -5.994. That is the 4th largest 5-day decline on record. The only higher cases occurred during November 8-13, 1959 (-6.439), January 20-25, 1976 (-6.036), and January 19-24, 1976 (-5.997). Daily recordkeeping began on January 1, 1950. On March 16 the MJO data was unavailable. The significant December 16-17 snowstorm during what has been a blocky December suggests that seasonal snowfall prospects have increased especially from north of Philadelphia into southern New England. At New York City, there is a high probability based on historic cases that an additional 20" or more snow will accumulate after December. Since January 1, New York City has picked up 28.1" snow. Winters that saw December receive 10" or more snow, less than 10" in January, and then 10" or more in February in New York City, saw measurable snowfall in March or April in 83% of cases. Winter 2009-2010 was the exception where only a trace of snow was recorded. This group of winters saw 6" or more snow during the March-April period in 50% of the cases. All said, it is more likely than not that there will be measurable snowfall after February. Based on sensitivity analysis applied to the latest guidance, there is an implied 74% probability that New York City will have a warmer than normal March. March will likely finish with a mean temperature near 43.7° (1.2° above normal).

SPC’s day 1 convective outlook: