donsutherland1

After a windy and relatively chilly day, a much more springlike day lies ahead for tomorrow. Readings will likely rise into the 60s in much of the Middle Atlantic region and well into the 50s in southern New England. The storm responsible for today's strong winds added to the high seasonal snowfall totals in Buffalo and Burlington. Buffalo has now received 116.1" snow (12th highest figure on record) and Burlington has picked up 101.6" snow (10th highest figure on record). Meanwhile, Atlanta has yet to receive any snowfall. After March 23, Atlanta had just 19 cases where it received snowfall, only one of which was measurable. That historical data suggests that it is very unlikely that Atlanta will see measurable snowfall this winter and the odds of its not seeing any snowfall for the first time on record are increasing. The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was +4.02 today. That was the first positive figure in 22 days. The SOI has been negative for 44 out of the last 46 days. Today's preliminary value of the Arctic Oscillation (AO) was +2.005. The AO has now been positive for 44 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 22, the MJO was in Phase 5 at an amplitude of 0.584 (RMM). The amplitude was higher than the March 21-adjusted figure of 0.311. Even as the prospect of measurable snowfall has largely disappeared, Central Park could see a low temperature of 32° or below next week. That could be New York City's last freeze of winter 2018-19. The 12z operational ECMWF has a snowfall during the April 1-2 period. However, its performance in forecasting snowfalls at that range this winter and early spring has been dismal. There remains little ensemble support for that idea. Finally, based on sensitivity analysis applied to the current guidance, the implied probability of New York City's having a colder than normal March has risen to 79% (58% for 1° or more below normal). In contrast, April continues to look to be warmer than normal.

Even as the models continue to slowly arrive at the conclusion that the season has changed, the increasing spring foliage has weighed in a lot more decisively. Below are a few scenes from the New York Botanical Garden:

The storm responsible for the rain last night and this morning is moving away. However, as it intensifies and slows in the Gulf of Maine, strong winds will develop. Tomorrow winds could gust as high as 50 mph in parts of the New York City region. The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was -5.60 today. It has been negative for 21 consecutive days and 44 out of the last 45 days. Today's preliminary value of the Arctic Oscillation (AO) was +1.922. The AO has now been positive for 43 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 21, the MJO moved into Phase 5 at an amplitude of 0.315 (RMM). The amplitude was higher than the March 20-adjusted figure of 0.166. However, another system could bring the risk of precipitation to the region during the March 26-28 period. However, the prospect for measurable snowfall in Boston, New York City, or Philadelphia has diminished. 　

As of 7 pm, New York City had received 0.36" rain bringing annual precipitation for 2019 to 9.46". As a result, the probability of a year in which 50.00" or more precipitation falls has increased to 51% (1971-2018 data). The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was -5.64 today. It has been negative for 20 consecutive days and 43 out of the last 44 days. Today's preliminary value of the Arctic Oscillation (AO) was +1.972. The AO has now been positive for 42 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 20, the MJO was in Phase 3 at an amplitude of 0.163 (RMM). The amplitude was much lower than the March 19-adjusted figure of 0.406. The amplitude was also the lowest since October 21, 2018 when the MJO had an amplitude of 0.153). Tonight into tomorrow, a strong storm will move along the coastline of the Northeastern United States. Much of the region could receive 0.50"-1.50" rain with locally higher amounts. A moderate to significant snowfall is possible in the Adirondacks, northern Vermont, northern New Hampshire, western Maine and parts of Quebec. Another system could bring the risk of precipitation to the region during the March 26-28 period. Some of the guidance suggests the possibility of at least some frozen precipitation from that latter system. Such an outcome would be consistent with historical experience. However, the persistent but low ensemble support for a 4" or more snowfall in Boston, New York City, or Philadelphia has diminished. Since 1869, New York City has had 10 cases during the March 1-7 period when 6.0" or more snow fell and the average temperature was 32.0° or below. All 10 cases had additional measurable snowfall afterward.

Through March 20, New York City had received 9.10" precipitation. That is 0.32" below normal. However, a storm will bring a widespread 0.50"-1.50" rain to the region later tomorrow and Friday. Some locally higher amounts are possible. As a result, the City's precipitation will likely move above normal. Based on sensitivity analysis applied to the computer guidance, the following are implied probabilities for specified amounts: 0.50" or more: 99% 0.75" or more: 94% 1.00" or more: 76% 1.25" or more: 43% 1.50" or more: 15% 1.75" or more: 3% During 2018, New York City received 65.55" precipitation making 2018 New York City's 4th wettest year on record. The implied probabilities of New York City's receiving 50.00" or more precipitation this year are as follows: Historic climate record (1869-2018): 27% 1971-2018 Period: 50% With the City's climate having grown wetter following 1970, the latter (50%) probability is probably more realistic. Even as such cities as Philadelphia, New York, Newark, and Boston see rain, a moderate to significant snowfall is possible across the Adirondacks, northern Vermont, northern New Hampshire, western Maine, and part of Quebec. Through March 20, Burlington had picked up 95.1" snow making winter 2018-19 that city's 17th snowiest winter on record. 2018-19 is also Burlington's snowiest winter since 2016-17 when 100.4" snow fell. The ranking for 2018-19 would be as follows for the following snowfall amounts: 1": 16th snowiest 2": 14th snowiest 4": 12th snowiest 6": 10th snowiest 8": 10th snowiest 10": 9th snowiest 12": 9th snowiest Meanwhile, Atlanta has received 0.0" snow through March 20. Atlanta has never had a winter without at least a trace of snow since snowfall records were kept beginning in 1928-29. During the span of its snowfall record, Atlanta had 25 days with a trace of snow (3 of which contained measurable snow) from March 21 through April 30, including 9 days in April. Atlanta's latest measurable snowfall was 7.9", which was recorded on March 24, 1983. That implies that Atlanta still has some probability of seeing at least a trace of snow this winter based on its historic climate record. Finally, there remains some ensemble support for a measurable snowfall in Boston, New York City, and/or Philadelphia during the March 26-28 period.

The historic March heat continued for a third day in parts of the Pacific Northwest. Select temperatures included: Cultus Lake, BC: 77° (old record: 67°, 1986) Olympia, WA: 79° (old record: 73°, 1986) Quillayute, WA: 79° (old record: 68°, 1968) Seattle: 79° (old record: 74°, 1915) Shelton, WA: 80° (old record: 68°, 2010) Seattle had three consecutive days during which the temperature rose to 75° or above during the March 18-20 period. The previous earliest stretch of 3 or more consecutive days with 75° or warmer high temperatures occurred during April 17-20, 2016. The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was -3.64 today. It has been negative for 19 consecutive days and 42 out of the last 43 days. Today's preliminary value of the Arctic Oscillation (AO) was +2.283. The AO has now been positive for 41 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 19, the MJO was in Phase 3 at an amplitude of 0.406 (RMM). The amplitude was slightly higher than the March 18-adjusted figure of 0.382. Tomorrow into Friday, a strong storm will move along the coastline of the Northeastern United States. Much of the region could receive 0.50"-1.50" rain with locally higher amounts. A moderate to significant snowfall is possible in the Adirondacks, northern Vermont, northern New Hampshire, western Maine and parts of Quebec. Another system could bring the risk of precipitation to the region during the March 26-28 period. Some of the guidance suggests the possibility of at least some frozen precipitation from that latter system. Such an outcome would be consistent with historical experience. A small number of the 12z EPS members continue to show 4" or more snow for Philadelphia, New York City, and Boston. Since 1869, New York City has had 10 cases during the March 1-7 period when 6.0" or more snow fell and the average temperature was 32.0° or below. All 10 cases had additional measurable snowfall afterward.

Select Record Temperatures (as of 3 pm EDT): Cultus Lake, BC: 68° (old record: 19.0°C/67°F, 1986) Middleton Island, AK: 46° (tied record set in 2005) Quillayute, WA: 70° (old record: 68°, 1968) Shelton, WA: 75° (old record: 68°, 2010) Sitka, AK: 62° (old record: 57°, 2016) Yellowknife, NT: 47° (old record: -0.4°C/31°, 1995)

Possibility of late-season measurable snow next week persists... Tomorrow into late Friday, a powerful storm will bring a moderate to heavy rainfall to the big cities of the northern Mid-Atlantic and southern New England regions. A general 0.50"-1.50" appears likely (with the higher amounts coming in north and west of of New York City). The greatest prospect of snowfall amounts of 4" or more exists in the Adirondacks, across northern Vermont and New Hampshire, western Maine, and northwest of Trois Rivieres and Quebec City. Some amounts of 6" or more are likely, especially in the Adirondacks and the region north and west of Trois Rivieres and Quebec City. At the height of the storm, travel from Quebec City to Chicoutimi could be very difficult. Next week, the March 26-28 period still appears to provide the potential for measurable snowfall in such cities as Boston, New York, and Philadelphia. The following number of EPS ensemble members shows 4" or more snow: Boston: 8/51 (5/51 have 10" or more) New York City: 6/51 Philadelphia: 6/51 Finally, based on sensitivity analysis applied to the latest guidance, the implied probability that March will wind up below normal in New York City is approximately 80%. The implied probability that New York City will have a mean temperature 1° or more below normal is 65%.

I'm really sorry to hear this. Your family and you are in my prayers. I hope there will be emergency assistance available for what is a real and still growing catastrophe.

Seattle's warmth today was historic. High temperature: 79° (old daily record: 76°, 1928; old March record: 78°, 3/29/2004) Warmest reading in the October 23-March 31 period. Low temperature: 59° (old daily record: 50°, 1997 and 2016; old March record: 57°, 3/10/1900) Highest minimum temperature for both March and April. Warmest minimum temperature for the October 21-May 8 period. CXYH in the Northwest Territories hit 71 today.

Many monthly records are falling in western Canada. At 7 pm EDT, Abbotsford Airport and Cultus Lake, both in British Columbia, had a temperature of 24.1°C (75°F).

As of 3 pm PDT, the temperature had reached 79° at Seattle. That set a new March record high temperature. The previous monthly record was 78°, which was set on March 29, 2004. The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was -1.44 today. It has been negative for 41 out of the last 42 days. Today's preliminary value of the Arctic Oscillation (AO) was +1.940. The AO has now been positive for 40 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 18, the MJO was in Phase 3 at an amplitude of 0.382 (RMM). The amplitude was lower than the March 17-adjusted figure of 0.481. The MJO could approach or reach Phase 2 in the next day or so. Thursday into Friday, a strong storm will move along the coastline of the Northeastern United States. Much of the region could receive 0.50"-1.00" rain with locally higher amounts. Another system could bring the risk of precipitation to the region during the March 26-28 period. Some of the guidance suggests the possibility of at least some frozen precipitation from that latter system. Such an outcome would be consistent with historical experience. A small number of the 12z EPS members showed 4" or more snow. Since 1869, New York City has had 10 cases during the March 1-7 period when 6.0" or more snow fell and the average temperature was 32.0° or below. All 10 cases had additional measurable snowfall afterward.

Seattle reached 79 degrees at 3 pm PDT. That set a new monthly record high temperature.

I agree about the importance of the storm track. Last year, ISP saw 4.6" snow on April 2 and NYC saw 5.5" snow. It has been uncommon for ISP or NYC to have 2 or more consecutive years during which 2" or more snow fell during the March 25-April 30 period. ISP has had 1 such case (1996 and 1997) during its 57-year climate record; NYC has had 3. ISP would equate to around 3 over the same period of time as NYC's climate record. Neither location has had 2 or more consecutive years when 4" or more snow fell during the March 25-April 30 period. Then again, the 2010s have set a lot of snowfall records, so one can't completely rule out such a scenario, which appeared on a few of the EPS members (0z run).

Later this week, a storm will likely bring rain to parts of the Northeast, especially coastal areas. Accumulating snow is possible in higher elevations across Upstate New York, Quebec, and New England. The greatest risk of a moderate or significant snowfall (4” or more) exists in the higher elevations of Quebec north and west of Quebec City and in an area running across western Maine and northern New Hampshire. Next week could favor a better chance at a measurable snowfall. Some of the guidance is suggesting that the March 26-28 period could offer a window of opportunity for a measurable snowfall in at least parts of the Philadelphia to Boston corridor. But at this time scale, uncertainty remains high. The 0z EPS ensemble mean figures are: Boston: 3.0” (8/51 members at 4” or more; 4 of those members show 10” or more) New York City: 2.0” (5/51 members at 4” or more) Philadelphia: 1.0” (4/51 members at 4” or more) The 0z GGEM also highlighted the possibility of measurable snow. Some historical data is provided below for perspective as it relates to 4” or greater snowfalls for Boston, New York City, and Philadelphia in the March 25-April 30 timeframe: Even in Boston, a 4” or greater snowfall would be an infrequent event this late in the season.

A very weak system passed well south of the region today. However, none of its precipitation reached the New York City region and nearby suburbs. The ENSO Region 1+2 anomaly was +0.70°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.45°C and the ENSO Region 3.4 anomaly has averaged +0.80°C. Similar ENSO conditions will likely persist through much of March. The SOI was -8.86 today. It has been negative for 40 out of the last 41 days. Today's preliminary value of the Arctic Oscillation (AO) was +0.900. The AO has now been positive for 39 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 17, the MJO was in Phase 3 at an amplitude of 0.480 (RMM). The amplitude was lower than the March 16-adjusted figure of 0.635. The MJO could approach or reach Phase 2 in the next day or so. By the midweek, the temperature could be warmer than normal. There is some chance of another brief push of cooler air late in the week as a strong system passes offshore, possibly grazing the region with some light precipitation on Thursday into Friday. Another system could bring the risk of precipitation to the region during the March 26-28 period. Some of the guidance suggests the possibility of at least some frozen precipitation from that latter system. Such an outcome would be consistent with historical experience. Since 1869, New York City has had 10 cases during the March 1-7 period when 6.0" or more snow fell and the average temperature was 32.0° or below. All 10 cases had additional measurable snowfall afterward. Since 1950, 9/11 (82%) of New York City's 4" or greater snowstorms that occurred on or after March 20 occurred when the PNA was negative. The two that occurred with a positive PNA were the only two cases that featured an ENSO Region 1+2 anomaly > 0°C. None of the 11 cases occurred with the PNA at +1.000 or above. Smaller snowfalls, some of which exceeded 3.0", did occur when the PNA was at or above +1.000.

On numerous occasions this winter, the ECMWF has shown the snowiest solution that was at odds with the other guidance in the medium term and then wound up incorrect. The PNA+ and lack of support from its ensemble members suggests that this could be another such case. Seasonal climatology also argues for caution when it comes to the ECMWF’s snowy solution.

The ENSO Region 1+2 anomaly was +0.50°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 6. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.50°C and the ENSO Region 3.4 anomaly has averaged +0.69°C. Similar ENSO conditions will likely persist through much of March. The SOI was -9.10 today. It has been negative for 39 out of the last 40 days. Today's preliminary value of the Arctic Oscillation (AO) was +0.454. The AO has now been positive for 38 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 16, the MJO was in Phase 3 at an amplitude of 0.637 (RMM). The amplitude was lower than the March 15-adjusted figure of 0.706. The MJO could approach or reach Phase 2 in the next day or so. Tonight into tomorrow morning, a fast-moving weak system could bring some light rain or snow across parts of the northern Middle Atlantic region. However, the precipitation looks to pass south of New York City. By the middle of the week, temperatures could again be rising to levels above seasonal norms. There is some chance of another brief push of cooler air late in the week as a strong system passes offshore. Another system could bring the risk of precipitation to the region during the March 26-28 period.

Following last night's line of thunderstorms, some of which brought small hail to parts of the region, a cooler air mass has returned to the region. Temperatures struggled to reach 50° whereas yesterday the mercury soared into the 70s. The ENSO Region 1+2 anomaly was +0.50°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 6. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.50°C and the ENSO Region 3.4 anomaly has averaged +0.69°C. Similar ENSO conditions will likely persist through much of March. The SOI was -9.53 today. It has been negative for 38 out of the last 39 days. Today's preliminary value of the Arctic Oscillation (AO) was +0.677. The AO has now been positive for 37 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 15, the MJO was in Phase 3 at an amplitude of 0.707 (RMM). The amplitude was lower than the March 14-adjusted figure of 0.805. The MJO will likely remain in Phase 3 at a low amplitude for at least several days. Tomorrow night into Monday morning, a fast-moving weak system could bring some light rain or snow across parts of the northern Middle Atlantic region. However, most of the precipitation looks to pass south of New York City. Cities most likely to pick up a small accumulation (probably a coating to an inch) include Harrisburg, Philadelphia, and Trenton. By the middle of the week, temperatures could again be rising to levels above seasonal norms. There is some chance of another brief push of cooler air late in the week. Overall, the implied probability of a colder than normal March has rebounded to 66% based on sensitivity analysis applied to the latest guidance. In short, even as there have been fluctuations in the implied probabilities on account of the recent warmth, the overall idea of a colder than normal March as a whole for the New York City remains on track. April looks to be warmer than normal as per multiple pieces of guidance. Finally, through March 16 at 5 pm, Atlanta has received 0.0" snow. Since snowfall recordkeeping began, Atlanta has never had a winter when it received less than a trace of snow. Atlanta's snowfall records go back to 1928-29.

I am sorry to read of your mom’s passing. You have my fullest condolences.

Courtesy of the combination of breaks of sunshine and an exceptionally warm air mass aloft, today saw the warmest readings since last autumn. In a few locations, the mercury approached or reached the daily record high temperature. Some highlights: Albany: 72° (tied record set in 1989) -- warmest reading since October 11, 2018 (72°) Allentown: 74° -- warmest reading since October 11, 2018 (79°) New York City: 75° -- warmest reading since October 11, 2018 (77°) Newark: 77° -- warmest reading since October 11, 2018 (81°) Philadelphia: 77° -- warmest reading since October 11, 2018 (83°) Poughkeepsie: 72° -- warmest reading since October 11, 2018 (75°) Teterboro: 76° -- warmest reading since November 2, 2018 (79°) Trenton: 74° (old record: 72°, 1971 and 2002) -- warmest reading since October 11, 2018 (82°) Wilmington, DE: 79° -- warmest reading since October 11, 2018 (83°) The ENSO Region 1+2 anomaly was +0.50°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 6. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.50°C and the ENSO Region 3.4 anomaly has averaged +0.69°C. Similar ENSO conditions will likely persist through much of March. The SOI was -8.33 today. It has been negative for 37 out of the last 38 days. Today's preliminary value of the Arctic Oscillation (AO) was +1.381. The AO has now been positive for 36 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 14, the MJO moved into Phase 3 with at a low amplitude, 0.809 (RMM). The amplitude was lower than the March 13-adjusted figure of 1.063. The MJO will likely remain in Phase 3 at a low amplitude for at least several days. Following today's warmth, a brief shot of cooler air will move into the East. There is even the possibility of some light rain or snow across parts of the northern Middle Atlantic region on Monday morning. However, by late next week temperatures could again be rising to levels above seasonal norms. In part, the forecast strongly positive PNA will contribute to that outcome. Unlike during January and the first half of February, shorter wave lengths now result in the PNA's having a direct relationship with regional temperatures and an inverse relationship with snowfall prospects. During the March 16-31, 1950-2018 period, the mean temperature in New York City was +1.1° above climatology when the PNA was +1.000 or above. The mean temperature was 0.5° below climatology when the PNA was negative. In terms of snowfall, the frequency of measurable snow events in New York City was somewhat less than half of climatology when the PNA was +1.000 or above while that frequency was just over 40% above climatology when the PNA was negative. Based on the latest guidance, New York City's average temperature for the March 16-31 period could be approximately 1.6° above normal. As a result, the implied probability of a colder than normal March in New York City has decreased to 55%.

At 1 pm, the temperature was 71° in Philadelphia, 71° in Newark, and 70° in New York City. Those are the first 70° or warmer readings at those locations since November 2, 2018.

All other variables held constant, it would support milder readings—not exceptional warmth, but still on the warm side of normal for the closing week of March. Both the CFSv2 and EPS support such an idea.

The PNA+ could last for two weeks.

A brief spring preview is in order for tomorrow. Temperatures will very likely surge into the 60s as far north as southern New England and to or even above 70° in Washington, D.C. The ENSO Region 1+2 anomaly was +0.50°C and the Region 3.4 anomaly was +1.00°C for the week centered around March 6. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +0.50°C and the ENSO Region 3.4 anomaly has averaged +0.69°C. Similar ENSO conditions will likely persist through much of March. The SOI was -14.12 today. It has been negative for 36 out of the last 37 days. Today's preliminary value of the Arctic Oscillation (AO) was +1.990. The AO has now been positive for 35 consecutive days. The last time the AO was positive for at least that long was during the April 13, 2018 through June 3, 2018 period when the AO was positive for 52 consecutive days. Historic probabilities favor the continuation of a predominantly positive AO through the remainder of March. On March 13, the MJO was in Phase 4 at an amplitude of 1.059 (RMM). The amplitude was somewhat lower than the March 12-adjusted figure of 1.296. The MJO will likely move into Phase 3 and/or at a low amplitude in the next day or two. Following tomorrow's warmth, a brief shot of cooler air will move into the East. However, by late next week temperatures could again be rising above seasonal norms. In part, the forecast strongly positive PNA will contribute to that outcome. Unlike during January and the first half of February, shorter wave lengths now result in the PNA's having a direct relationship with regional temperatures and an inverse relationship with snowfall prospects. During the March 16-31, 1950-2018 period, the mean temperature in New York City was +1.1° above climatology when the PNA was +1.000 or above. The mean temperature was 0.5° below climatology when the PNA was negative. In terms of snowfall, the frequency of measurable snow events in New York City was somewhat less than half of climatology when the PNA was +1.000 or above while that frequency was just over 40% above climatology when the PNA was negative.