donsutherland1

A rose at the New York Botanical Garden:

Warmer temperatures lie ahead. The temperature will rise to above normal levels for tomorrow through Thursday. Exceptional heat is unlikely. It will turn somewhat cooler to end the week. The ENSO Region 1+2 anomaly was +2.1°C and the Region 3.4 anomaly was +1.0°C for the week centered around May 20. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +1.72°C and the ENSO Region 3.4 anomaly has averaged +0.83°C. The ongoing El Niño will continue to strengthen through the summer. The SOI was -25.41 today. The preliminary Arctic Oscillation (AO) was +1.581 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 70% probability that New York City will have a warmer than normal May (1991-2020 normal). May will likely finish with a mean temperature near 63.8° (0.6° above normal). Supplemental Information: The projected mean would be 1.3° above the 1981-2010 normal monthly value.

The final numbers from today's historic heat in France:

It took awhile, but by last Tuesday, the models started to present a strong heat signal.

The Met Office has now published an account of today's historic May heat. That account can be found at: https://www.metoffice.gov.uk/about-us/news-and-media/media-centre/weather-and-climate-news/2026/provisional-spring-daily-temperature-record-as-heatwave-continues In terms of the impact of climate change, the Met Office explains: A climate attribution study published last summer by Met Office scientists found that the chances of surpassing the May temperature record have been increasing as our climate changes as a consequence of human greenhouse gas emissions. The study found that breaking the 32.8°C May record is around three times more likely now in our current climate than it would have been in a natural climate not impacted by greenhouse gas emissions. What was around a 1-in-100 year event is now around a 1-in-33 year event.

Today, London's Kew Gardens saw the temperature soar to 34.8°C (95°F). That demolished the UK's national May record of 32.8°C (91F) that had stood since 1944. The ongoing extreme heat was made much more likely by anthropogenic climate change. Across the British Channel, France saw more than 300 May monthly records set with 62 locations having reaching 95°F (35.0°C) or above. Final numbers from France will be available in a few hours.

A historic May heatwave is scorching parts of Europe, including the UK, France, Germany, Italy, and Spain. Today, France saw 105 stations set new monthly records with 25 of those stations setting monthly records that had been set on Friday or yesterday. Tomorrow and Tuesday will likely be hotter. The UKs national May temperature record could be challenged or broken tomorrow and again on Tuesday. The extreme heat has been made more likely by climate change. Europe is currently experiencing a rate of warming that is twice the rate of the global average. From Climate Central's Climate Shift Index:

Yes. It is consistent with a rapidly strengthening El Niño. New weekly numbers come out tomorrow.

Through 4 pm, storm total rainfall totals across the region include: Atlantic City: 0.91" Binghamton: 0.86" Bridgeport: 1.44" Islip: 1.20" New Haven: 1.38" New York City-Central Park: 1.83" New York City-JFK Airport: 1.56" New York City-LaGuardia Airport: 1.65" Newark: 1.50" Philadelphia: 1.52" White Plains: 1.38" Clouds will break tomorrow. As a result, the temperature will likely return to the lower 70s. Temperatures could then rise to above normal levels for Tuesday through Thursday. It will turn somewhat cooler to end the week. The ENSO Region 1+2 anomaly was +1.8°C and the Region 3.4 anomaly was +0.9°C for the week centered around May 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +1.63°C and the ENSO Region 3.4 anomaly has averaged +0.70°C. El Niño conditions are now in place. The ongoing El Niño will continue to strengthen through the summer. The SOI was -31.69 today. The preliminary Arctic Oscillation (AO) was +1.772 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 75% probability that New York City will have a warmer than normal May (1991-2020 normal). May will likely finish with a mean temperature near 64.0° (0.8° above normal). Supplemental Information: The projected mean would be 1.5° above the 1981-2010 normal monthly value.

That was a typo. The record low was 44 in 1963.

Through 4 pm, rainfall totals across the region include: Bridgeport: 0.24" Islip: 0.09" New Haven: 0.08" New York City-Central Park: 0.11" New York City-JFK Airport: 0.02" New York City-LaGuardia Airport: 0.12" Newark: 0.01" Philadelphia: 0.39" White Plains: 0.19" Rain will continue tonight into tomorrow at varying intensities. A storm total 0.50"-1.50" rainfall is likely in the New York City area (generally 1.00"-1.50" in New York City and its nearby suburbs) with some locally higher amounts near 2.00". Many parts of the region will see the temperature fall to 50° or even somewhat lower tonight. The temperature will then struggle to reach the lower 60s tomorrow. The mercury will likely return to the lower 70s on Monday. Temperatures could return to above normal levels for Tuesday through Thursday. The ENSO Region 1+2 anomaly was +1.8°C and the Region 3.4 anomaly was +0.9°C for the week centered around May 13. For the past six weeks, the ENSO Region 1+2 anomaly has averaged +1.63°C and the ENSO Region 3.4 anomaly has averaged +0.70°C. El Niño conditions are now in place. The ongoing El Niño will continue to strengthen through the summer. The SOI was -18.21 today. The preliminary Arctic Oscillation (AO) was +1.454 today. Based on sensitivity analysis applied to the latest guidance, there is an implied near 73% probability that New York City will have a warmer than normal May (1991-2020 normal). May will likely finish with a mean temperature near 63.9° (0.7° above normal). Supplemental Information: The projected mean would be 1.4° above the 1981-2010 normal monthly value.

I agree. This is a very challenging setup.

Latest NBE: My thinking is that most of the area will see a general 1.00"-1.50" with some locally higher amounts. The NBE has lowered the top amounts while raising the lower amounts. The 0.50" figure will be confined to locations farther from the NYC area than had been my thinking last evening. The 6z GFS, 0z GGEM and 0z AIFS are in good agreement. The 0z ECMWF became notably wetter. However, it is an outlier among the operational models. The key to achieving higher amounts, particularly those on the ECMWF, would be convective activity, possibly training thunderstorms. At present, most of the convective activity will likely take place south of the NYC region

I'm giving greater weight to the AIFS/ECMWF, as the 18z GFS reduced totals from the 12z run. I do think 2" amounts are most likely across eastern PA into western NJ. The City and nearby suburbs should generally be 1.00"-1.50" in my thinking, but parts of CT away from the coast will have lower amounts (0.50"-1.00"). That's why I used 0.50"-1.50" with some locally higher amounts for the general NYC area. On the other hand, the NBE has grown wetter with amounts near 1.70" in and around NYC.

Yes. I remember it well. The afternoon snow squall, even as it was short-lived, was quite impressive.