donsutherland1

Yes. I think we will get some shots at snow in December even if the month is warm overall.

The kind of sustained blocking necessary to lock in a prolonged cold pattern is lacking. Transient blocks won’t cut it, unfortunately. November still appears likely to be warmer than normal. December could be, as well.

I agree. The forecast upper air pattern is not conducive to its coming north. It will likely make a sharp turn to the right. Whether that happens from eastern North Carolina or extreme southeast Virginia is still somewhat uncertain. The former is probably the more likely outcome.

In the wake of yesterday's rainstorm, cooler weather and gusty winds prevailed. Milder conditions will gradually return in coming days. Tropical Storm Nestor will likely make landfall over the Florida Panhandle tonight and then track rapidly to the east northeast. Its rain should pass south of the New York City Metro area on Sunday night. Parts of the Middle Atlantic region including Washington and Baltimore could see some showers from Nestor. The last week of October will likely start mild but end with a cool shot. The cool conditions increasingly appear likely to persist through the first week of November as the Arctic Oscillation goes negative for a time. The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was +0.4°C for the week centered around October 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.88°C and the ENSO Region 3.4 anomaly has averaged +0.12°C. A neutral ENSO is currently the base case for Winter 2019-20. The SOI was +2.25 today. Today, the preliminary Arctic Oscillation (AO) figure was -0.594. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. Despite what might be a somewhat cooler than normal start to November, a warmer outcome still appears more likely than not. On October 17, the MJO was in Phase 1 at an amplitude of 1.115 (RMM). The October 16-adjusted amplitude was 0.981. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. Based on the sensitivity analysis, the estimated October mean temperature is currently near 58.5°. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 73%.

Yes. It was a historic storm.

In the wake of yesterday's rainstorm, cooler weather and gusty winds prevailed. Milder conditions will gradually return in coming days. However, a possible tropical cyclone could develop over the Bay of Campeche and make landfall in Louisiana and later bring clouds and at least some rain to the region early next week. If so, readings could be cooler than had previously been modeled. The last week of October will likely start mild but end with a cool shot. The cool conditions increasingly appear likely to persist through the first week of November as the Arctic Oscillation goes negative for a time. The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was +0.4°C for the week centered around October 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.88°C and the ENSO Region 3.4 anomaly has averaged +0.12°C. A neutral ENSO is currently the base case for Winter 2019-20. The SOI was +2.58 today. Today, the preliminary Arctic Oscillation (AO) figure was -0.461. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. Despite what might be a somewhat cooler than normal start to November, a warmer outcome still appears more likely than not. On October 16, the MJO was in Phase 1 at an amplitude of 0.981 (RMM). The October 15-adjusted amplitude was 1.004. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. Based on the sensitivity analysis, the estimated October mean temperature is currently near 58.5°. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 70%.

Boston's barometer bottomed out at 975.3 mb (28.80") and Concord's reached a minimum pressure of 973.0 mb (28.73").

As of 11 pm, New Haven had picked up 2.08" rain. That broke the October 16 daily record of 1.95", which was set in 1974. At New York City's LaGuardia Airport, daily rainfall had reached 1.71". That broke the daily record of 1.64", which was set in 1974. At 11:05 pm, Poughkeepsie's daily rainfall had reached 1.80". That surpassed the daily record of 1.79" from 1974.

With 2.10" as of 10 pm, White Plains has set a new daily precipitation record for October 16. The old record was 1.98", which was set in 1974.

With 0.66" rain in the past hour, Newark's rainfall for today has reached 1.94". That surpasses the previous record for October of 1.42", which was set in 1974.

Much of the region is well on the way toward receiving a general 1.00"-2.00" rainfall. Some areas could see even higher amounts. As of 8 pm, rainfall totals included: Allentown: 2.22" (old record: 1.23", 2002); Atlantic City: 1.21"; Bridgeport: 0.65"; Harrisburg: 1.25"; Islip: 0.91"; New Haven: 0.63"; New York City-JFK: 0.93"; New York City-LGA: 1.39"; Newark: 1.28"; Philadelphia: 1.14"; Scranton: 0.94"; and, White Plains: 1.57". With today's rainfall, Allentown's annual precipitation has now reached 50.63". That ranks 2019 as Allentown's 20th wettest year on record. 2019 is the 3rd consecutive year that Allentown has seen 50" or more precipitation. That ties the record set in 1951-53 and tied in 2003-05 for most consecutive years with 50" or more precipitation. Following the storm, cooler weather and gusty winds will give way to another round of warmer than normal temperatures. However, a possible tropical cyclone could develop over the Bay of Campeche and make landfall in Louisiana and later bring clouds and at least some rain to the region early next week. If so, readings could be cooler than had previously been modeled. The last week of October will likely start mild but end with a cool shot. The cool conditions could linger into the first few days of November, but overall the cool shot will likely be transient in nature, not the start of a long-duration cold pattern. Some uncertainty has increased as there is a risk that the Arctic Oscillation could go negative for at least a period beginning in late October. The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was +0.4°C for the week centered around October 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.88°C and the ENSO Region 3.4 anomaly has averaged +0.12°C. The strong cooling that took place in Region 1+2 during September indicates that the prospects for a neutral-cool ENSO during the winter have increased. A neutral ENSO is currently the base case for Winter 2019-20. The SOI was -2.52 today. Today, the preliminary Arctic Oscillation (AO) figure was -0.457. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. On October 15, the MJO was in Phase 1 at an amplitude of 1.000 (RMM). The October 14-adjusted amplitude was 1.285. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. Based on the sensitivity analysis, the estimated October mean temperature is currently near 59.5°. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 73%. 　 　

As of 3:05 pm, Richmond had picked up 1.29" rain today. That broke the daily rainfall record of 0.85", which was set in 1964.

The biggest rainfall in several months and possibly within the past year for parts of the region is now poised to affect the New York City area. Areas of moderate rain were advancing to the north and west of the region with moderate rain recently falling at Allentown. Farther south, rain has been falling heavily in Washington, DC and Baltimore for the past 1-2 hours. As of 1:39 pm, Washington, DC had picked up 1.09" rain. The daily record there is 1.38", which was set in 2002.

The heaviest precipitation in several months appears likely for parts of the region tomorrow into Thursday. A general 1.00"-2.00" rainfall now appears likely. Some areas, especially on Long Island, will likely see even higher amounts. The last time New York City received 1.00" or more rain in a day was August 22 when 1.01" fell. The last time New York City picked up 1.50" rain in a day was July 22 when 1.66" fell. The last time New York City received 2.00" or more rain in a day was August 11, 2018 when 2.90" fell. Following the storm, cooler weather will give way to another round of warmer than normal temperatures. The last week of October will likely start mild but end with a cool shot. The cool conditions could linger into the first few days of November, but overall the cool shot will likely be transient in nature, not the start of a long-duration cold pattern. The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was +0.4°C for the week centered around October 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.88°C and the ENSO Region 3.4 anomaly has averaged +0.12°C. The strong cooling that took place in Region 1+2 during September indicates that the prospects for a neutral-cool ENSO during the winter have increased. A neutral ENSO is currently the base case for Winter 2019-20. The SOI was -13.60 today. Today, the preliminary Arctic Oscillation (AO) figure was +0.044. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. On October 14, the MJO was in Phase 1 at an amplitude of 1.285 (RMM). The October 13-adjusted amplitude was 1.333. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. Based on the sensitivity analysis, the estimated October mean temperature is currently near 59.5°. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 78%. Finally, Arctic sea ice extent on JAXA was 4.943 million square kilometers on October 14. That was the latest sub-5 million square kilometer extent on record. The previous latest date was October 13.

Usually, that's the case.

Not in this case. The closer low is forecast to rapidly deepen. In most cases, the offshore low is dominant and/or deepening, pulling the moisture offshore.

One is dealing with dual centers. On the 0z ECMWF, between hours 48 and 51, a developing second center crosses western/central Long Island while another center is offshore. The second center rapidly intensifies and reaches just under 980 mb over Rhode Island and continues north-northeastward into eastern New Hampshire by 60 hours. The offshore center passes southeast of Nantucket and then into the Gulf of Maine from 54 hours to 60 hours. JFK has received 39.07" precipitation, which is 4.89" above normal for this time of year.

The recent dry spell has led to New York City's precipitation having fallen below normal on a year-to-date basis. In addition, the implied probability of New York City's seeing 50" or more precipitation this year has decreased to 45%. However, there is strong model consensus that the region will likely experience its biggest rainstorm in several months as a strong nor'easter moves across western Long Island into New England. Widespread 1"-2" rainfall amounts with local amounts in excess of 3" appears likely tomorrow into Thursday. Below is a summary of the precipitation status for select cities:

Much of the region experienced bright sunshine and readings in the 70s today. The heaviest precipitation in several months appears likely for parts of the region Wednesday into Thursday. For New York City, 84% of the EPS members show 1.00" or more precipitation; 71% show 1.50" or more precipitation; and, 41% show 2.00" or more. Therefore, a general 1.00"-2.00" rainfall now appears likely. Some areas, especially on Long Island, will likely see even higher amounts. The last time New York City received 1.00" or more rain in a day was August 22 when 1.01" fell. The last time New York City picked up 1.50" rain in a day was July 22 when 1.66" fell. The last time New York City received 2.00" or more rain in a day was August 11, 2018 when 2.90" fell. Following the storm, cooler weather will give way to another round of warmer than normal temperatures. The last week of October will likely start mild but end with a cool shot. The cool conditions could linger into the first days of November, but overall the cool shot will likely be transient in nature, not the start of a long-duration cold pattern. The ENSO Region 1+2 anomaly was -1.0°C and the Region 3.4 anomaly was +0.4°C for the week centered around October 9. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.88°C and the ENSO Region 3.4 anomaly has averaged +0.12°C. The strong cooling that took place in Region 1+2 during September indicates that the prospects for a neutral-cool ENSO during the winter have increased. A neutral ENSO is currently the base case for Winter 2019-20. The SOI was -5.74 today. Today, the preliminary Arctic Oscillation (AO) figure was +0.654. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. On October 13, the MJO was in Phase 8 at an amplitude of 1.334 (RMM). The October 12-adjusted amplitude was 1.225. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. Based on the sensitivity analysis, the estimated October mean temperature is currently 59.2°. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 74%. Finally, on account of very slow ice growth, Arctic sea ice extent for October 13 was a daily record low figure of 4.881 million square kilometers. There is a chance that today's figure will be the latest ever figure under 5 million square kilometers.

Under crystal clear skies and brilliant sunshine, the temperature soared into the lower 70s today. Even as the calendar has advanced deeper into autumn, the day had almost a late September feel to it. The Monarch migration remained well underway.

On JAXA, Arctic sea ice extent was 4,880,849 square kilometers on October 13. That figure is now below the 2012 extent for the same date. In 2012, Arctic sea ice extent was 4,911,701 square kilometers.

Unseasonably mild weather will prevail into midweek. Afterward, a short period of cooler weather will be followed by another warmer pattern for the southern New England areas. This cooler weather will likely coincide with a mid-week system that could bring much of the region 0.50"-1.50" rain with locally higher amounts. The last time New York City received 1.00" or more rain in a day was August 22 when 1.01" fell. The last time New York City picked up 1.50" rain in a day was July 22 when 1.66" fell. After August 22, New York City has picked up just 2.26" rain in total. The last week of October will likely start mild but end with a cool shot. The cool shot will likely be transient in nature. The ENSO Region 1+2 anomaly was -0.6°C and the Region 3.4 anomaly was +0.5°C for the week centered around October 2. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.78°C and the ENSO Region 3.4 anomaly has averaged +0.02°C. The strong cooling that took place in Region 1+2 during September indicates that the prospects for a neutral-cool ENSO during the winter have increased. Since 1991 when weekly ENSO region data was available, five years have seen September record two or more weeks with -1.0°C or cooler weekly anomalies in Region 1+2: 1996, 1999, 2007, 2010, and 2017. 4/5 (80%) of those cases went on to feature warm December-February temperature anomalies in the Middle Atlantic and southern New England regions. Those cases include La Niña winters. However, the larger pool of neutral-cool ENSO winters, many of which predate the weekly ENSO regional data, have often featured frequent Atlantic blocking. For now, there is a mixed winter signal. The SOI was +8.12 today. Today, the preliminary Arctic Oscillation (AO) figure was +0.957. Since 1950, there have been five prior cases when the AO averaged -0.500 or below in both July and August: 1950, 1958, 1960, 1968, and 2015. The average temperature for September through November in New York City was 58.9° (59.6° adjusted). All cases featured a warmer than normal fall. The potential for autumn 2019 to rank among the 30 warmest cases on record has increased in recent weeks. For New York City, that would translate into a September-November mean temperature of at least 58.8°. In August, the AO averaged -0.722 and in September the AO rose to +0.306. The possible transition to predominantly positive values from September into October has been a relatively uncommon occurrence. Since 1950, only 1963 and 2011 saw a transition of an August value of -0.500 or below to positive values in September and a positive average in October. Both cases featured a warmer than normal November in the Middle Atlantic and southern New England areas. On October 12, the MJO was in Phase 8 at an amplitude of 1.226 (RMM). The October 11-adjusted amplitude was 1.143. In the two prior cases when the MJO moved into Phase 1 in late September or early October and then remained in Phase 1 for 12 or more consecutive days as occurred this year, the average decline in the 14-day average temperature for the 2-3 weeks that followed the MJO's moving out of Phase 1 was gradual. The current long-duration Phase 1 episode suggests that the second half of October could be warmer than normal. For New York City, an October mean temperature of 58.5°-59.5° (1.6° to 2.6° above normal) would be implied by those earlier long-duration Phase 1 cases. The first week of November and possibly beyond could be warmer than normal overall. Based on sensitivity analysis applied to the latest guidance, the implied probability of New York City having a warmer than normal October is approximately 78%.

October 29, 1971 when the temperature hit 80.

2005-06. 40.0”

It is typically a signal of a warmer winter. Since 1980, the following has occurred in New York City when both October and November were warmer than normal: Succeeding winter: Colder than normal: 3/13 (23%) cases Near normal: 1/13 (8%) cases Warmer than normal: 9/13 (69%) cases Breakdown of months: December: Colder than normal: 4/13 (31%) months Warmer than normal: 9/13 (69%) months January: Colder than normal: 2/13 (15%) months Warmer than normal: 11/13 (85%) months February: Colder than normal: 2/13 (15%) months Warmer than normal: 11/13 (85%) months December-February: Colder than normal months: 8/39 (21%) months Warmer than normal months: 31/39 (79%) months The snowfall signal was mixed. Mean: 24.2" Median: 24.9" Lowest: 3.5", 2001-02 Highest: 61.9", 2010-11 <10": 2/13 (15%) cases < 20": 5/13 (38%) cases 20" or more: 8/13 (62%) cases 30" or more: 5/13 (31%) cases 40" or more: 2/13 (15%) cases