donsutherland1

Kansas City will likely see its first measurable snowfall after April 15 since May 2, 2013 when 0.5" fell. The last time a post-April 15 storm brought more than 1" of snow to Kansas City was April 20, 1992 when 2.7" fell. I doubt St. Louis will have measurable snow. The last time St. Louis had measurable snow after April 15 was April 18, 1997 when 0.1" was recorded. The climate database shows May 6, 1998, but that is wrong, as the minimum temperature was 62 degrees. That was hail, not snow. It should have been flagged by quality control given the minimum temperature, alone. There is only one case where both Kansas City and St. Louis received measurable snow on the same day after April 15: April 24, 1910 when Kansas City picked up 0.1" and St. Louis received 1.1".

Detroit had a trace of snow from the system that impacted us and then 0.5" from a follow-up system.

It's possible that some of the NE PA mountains could pick up a coating of snow.

All of the NYC area sites are currently running above normal through yesterday: EWR: +1.1 JFK: +1.3 LGA: +2.2 NYC: +1.8 This week's brief cold shot won't be sufficient to erase these warm anomalies. Moreover, today and tomorrow could add to those warm anomalies.

Morning thoughts... Today will be partly sunny and warm. High temperatures will likely reach the middle and upper 60s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 66° Newark: 67° Philadelphia: 68° Tomorrow will be sunny unseasonably warm. Temperatures will likely reach or exceed 70° in much of the region. At the same time, a storm could bring 1”-3” of snow to Detroit on tomorrow into Wednesday. Detroit’s most recent measurable snow on or after April 20 occurred on May 10, 2020 when 0.5” of snow fell. Detroit’s daily snowfall records are: April 20: 1.2”, 1947 April 21: 0.3”, 1978

Detroit and Toledo continue to be in line for what appears to be a 2” or greater snowfall for Tuesday into Wednesday (April 20-21). Toledo has had four prior snowfalls of 1” or more on or after April 20: April 21, 1922: 2.0” May 8-9, 1923: 4.0” May 6-7, 1989: 1.3” April 23-24, 2005: 4.0” The most recent measurable snowfall on or after April 20 occurred on April 20, 2013 when 0.3” snow was measured. Daily snowfall records are: April 20: Detroit: 1.2”, 1947; Toledo: 0.3”, 2013 April 21: Detroit: 0.3”, 1978; Toledo: 2.0”, 1922

Tomorrow and Tuesday will be springlike days. The temperature could surge above 70° in much of the region on Tuesday. A sharp cold front will likely cross the region on Wednesday, possibly with a squall line, bringing a short period of much below normal readings. Thursday morning could see the temperature fall below 40° in New York City. Meanwhile, a storm will likely bring accumulating snow to parts of the Great Lakes region on Tuesday into Wednesday. Detroit could see 2" or more of snow on or after April 20 for only the 5th time on record. Detroit's last measurable snowfall on or after April 20 occurred just last year on May 10, 2020 when 0.5" of snow was measured. 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 April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -1.01 today. The preliminary Arctic Oscillation (AO) figure was +0.191 today. On April 17 the MJO was in Phase 7 at an amplitude of 1.749 (RMM). The April 16-adjusted amplitude was 1.573 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 62% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.8° (0.8° above normal).

Morning thoughts... Today will be partly sunny and milder. 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): 64° Newark: 64° Philadelphia: 64° Tomorrow will be sunny and mild. The first half of next week will be noticeably warmer with readings well into the 60s with perhaps a day where they reach or exceed 70°. At the same time, a storm could bring 2” or more of snow to Detroit on Tuesday into Wednesday. Since 1874, Detroit has had only four storms of 2” or more snow on or after April 20: May 21-22, 1883: 5.0”; April 29, 1909: 3.0”; May 9, 1923: 6.0”; April 23-24, 2005: 4.3”. Detroit’s most recent measurable snow on or after April 20 occurred on May 10, 2020 when 0.5” of snow fell.

Yes. A total of 1.6” fell during 4/19-20.

For reference, Detroit has seen seven storms bring 1” or more snow on or after April 20. There is a chance that next week could add to the list. Those past storms are: May 21-22, 1883: 5.0” April 29, 1909: 3.0” April 22, 1911: 1.0” May 13, 1912: 1.5” May 9, 1923: 6.0” April 23-24, 1967: 1.7” April 23-24, 2005: 4.3” The most recent date on or after April 20 that saw measurable snowfall was May 10, 2020 when 0.5” accumulated.

I believe the issue lies with the sites from which the images were linked. They don’t archive their maps and old maps are removed after some period of time.

The possibility of minimum temperatures in the 30s on Thursday and then the 26th and perhaps 27th are more likely than 80s.

While that would fit with the recent MJO passage, I am somewhat skeptical especially given the other guidance. Last week, I was more bullish about such an outcome so to speak. It’s not out of the question, but not as likely as I had previously thought.

This afternoon, the weather was mostly cloudy at the New York Botanical Garden. The spring evolution continues uninterrupted.

Today saw variably cloudy skies with readings topping out in the middle 50s. Tomorrow will be somewhat warmer. Monday and Tuesday could feature readings in the 60s on Monday and even the 70s on Tuesday. A sharp cold front will likely cross the region on Wednesday bringing a short period of much below normal readings. The recent model runs have now turned colder for the remaining week of April. That development will bear watching. 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 April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -4.54 today. The preliminary Arctic Oscillation (AO) figure was +0.499 today. On April 15 the MJO was in Phase 7 at an amplitude of 1.611 (RMM). The April 14-adjusted amplitude was 1.725 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 60% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.7° (0.7° above normal).

Under partly sunny skies, the temperature rose into the lower 50s late in the morning.

Morning thoughts... Today will be partly sunny and a bit milder. High temperatures will likely reach the middle and upper 50s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 55° Newark: 56° Philadelphia: 56° Tomorrow will be sunny and milder. The first half of next week will be noticeably warmer with readings well into the 60s with perhaps a day where they reach or exceed 70°.

Parts of New Hampshire picked up 13.0" snow. Snow will wind down across New England tonight. A slow warming trend will commence during the weekend. The recent model runs have now turned colder for the remaining week of April. That development will bear watching. 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 April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was +4.11 today. The preliminary Arctic Oscillation (AO) figure was +0.537 today. On April 14 the MJO was in Phase 7 at an amplitude of 1.725 (RMM). The April 13-adjusted amplitude was 1.861 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 65% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 53.8° (0.8° above normal).

Morning thoughts... A slowly departing storm was bringing snow and rain to parts of New England. Today will start with partly sunny skies, but clouds could increase during the afternoon. High temperatures will likely reach the middle 50s in most of the region. Likely high temperatures around the region include: New York City (Central Park): 55° Newark: 56° Philadelphia: 56° Temperatures will gradually increase during the weekend.

A developing storm will bring periods of rain to parts of the region overnight, particularly eastern sections. Meanwhile, a snowstorm will rage in the Berkshire, Green and White Mountains. There, 6"-12" of wet snow with locally higher amounts is likely. Worcester will likely pick up 2"-4" of snow. There is an outside chance that Boston could pick up a small accumulation. The last time Boston saw measurable snowfall in April was just last year on April 18, 2020 when 0.7" snow was measured. In the wake of the storm, tomorrow will be variably cloudy and blustery. Temperatures will likely top out in the middle 50s. However, a slow warming trend will likely commence during the weekend. The latest EPS weeklies notwithstanding, the closing week of April could turn noticeably warmer. Since 1974, there were 7 cases where the MJO reached Phase 6 at an amplitude of 1.500 or above during April 5-15, as was the case this year. Only 1981 had an April 20-30 maximum temperature below 80° (75°). The average highest figure for such cases was 81.3°. Therefore, it is more likely than not that April 2021 will have a maximum monthly temperature of 80° or above. 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 April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -4.26 today. The preliminary Arctic Oscillation (AO) figure was +0.265 today. On April 14 the MJO was in Phase 7 at an amplitude of 1.725 (RMM). The April 13-adjusted amplitude was 1.862 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 67% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 54.0° (1.0° above normal).

Morning thoughts... A developing storm will bring rain to the northern Middle Atlantic region to New England. In parts of upstate New York, central and northern New England, colder air working into the deepening storm’s circulation will result in a changeover to snow. A 6”-12” snowfall with some higher amounts is possible in the Berkshire, Green, and White Mountains. However, even Worcester will likely pick up 2”-4” of wet snow with locally higher amounts of around 6” in the vicinity of Worcester. There is a small chance that the precipitation could even change to a period of snow for a time in the Boston area producing a small slushy accumulation. High temperatures will likely 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: 58° Philadelphia: 63° Tomorrow will be variably cloudy and blustery. Temperatures will gradually increase during the weekend.

Much of the region basked in springlike readings in the upper 60s and lower 70s. However, the next several days will be much colder. A developing storm will likely impact the region tomorrow into Friday. While a cool rain is likely from Philadelphia to New York City, there is the potential for an area of accumulating snow that will run across central and upstate New York State and central and northern New England. The greatest accumulations should be confined to higher elevations. Temperatures will likely stay in the lower 50s in New York City and Newark tomorrow. The latest EPS weeklies notwithstanding, the closing week of April could turn noticeably warmer. Since 1974, there were 7 cases where the MJO reached Phase 6 at an amplitude of 1.500 or above during April 5-15, as was the case this year. Only 1981 had an April 20-30 maximum temperature below 80° (75°). The average highest figure for such cases was 81.3°. Therefore, it is more likely than not that April 2021 will have a maximum monthly temperature of 80° or above. 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 April 7. For the past six weeks, the ENSO Region 1+2 anomaly has averaged -0.15°C and the ENSO Region 3.4 anomaly has averaged -0.52°C. La Niña conditions will likely give way to neutral-cool ENSO conditions as the spring progresses. The SOI was -19.69 today. The preliminary Arctic Oscillation (AO) figure was -0.336 today. On April 13 the MJO was in Phase 7 at an amplitude of 1.863(RMM). The April 12-adjusted amplitude was 1.951 (RMM). Based on sensitivity analysis applied to the latest guidance, there is an implied 60% probability that New York City will have a warmer than normal April. April will likely finish with a mean temperature near 54.0° (1.0° above normal).

FYI: https://www.weather.gov/media/climateservices/Normals_Information_Handout_February_2021.pdf

October 2011. The spring equivalent might be the May 1977 snowfall (even as NYC received only a trace).

The morning should be mainly sunny. Clouds will increase during the afternoon.