bluewave

Another top 10 warmest month so far for several of our stations around the area. Time Series Summary for ISLIP-LI MACARTHUR AP, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1999 78.6 0 2 2019 78.1 0 3 2013 78.0 0 - 2010 78.0 0 4 2020 77.7 0 5 2011 77.6 0 6 2023 77.5 2 7 1994 77.3 0 8 2022 77.1 0 9 2016 76.8 0 10 1966 76.3 0 Time Series Summary for LAGUARDIA AIRPORT, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2020 82.9 0 2 2010 82.8 0 3 1999 81.9 0 4 2019 81.5 0 5 2013 81.2 0 6 2022 81.1 0 - 2016 81.1 0 7 1955 80.9 0 8 2023 80.8 2 - 1966 80.8 0 9 2006 80.7 0 10 1994 80.6 0 Time Series Summary for WESTCHESTER CO AP, NY - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 1999 78.5 1 2 2013 77.0 0 - 2010 77.0 0 3 2020 76.9 0 4 2022 76.8 0 - 2019 76.8 0 5 2023 76.7 3 - 1966 76.7 0 - 1955 76.7 2 6 2011 76.6 1 7 2012 76.4 0 8 2016 76.3 0 - 1983 76.3 1 9 1952 76.2 0 Time Series Summary for NEWARK LIBERTY INTL AP, NJ - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Avg Temperature Missing Count 1 2011 82.7 0 2 2022 82.6 0 3 1993 82.5 0 4 2010 82.3 0 5 1994 81.9 0 6 2023 81.0 2 7 2013 80.9 0 8 2020 80.8 0 - 2012 80.8 0 - 1999 80.8 0 9 2019 80.6 0 10 1955 80.5 0

Record high average dewpoints this month near the coast and 2nd place at Newark. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=76&network=NJ_ASOS&station=EWR&season=jul&varname=feel&agg=mean&year=1893&w=bar&hours=0-23&_r=t&dpi=100&_fmt=png

The mid to upper 90s made it to NJ along with Brooklyn and Queens away from the sea breeze. You knew that Central Park wasn’t making it to 100° due to the overgrowth covering the sensor. The models and many forecasters don’t take that into account. Most don’t realize how dense the tree and plant growth has been around the NYC ASOS. Data for July 26, 2023 through July 29, 2023 Click column heading to sort ascending, click again to sort descending. Name Station Type Highest Max Temperature LONG BRANCH-OAKHURST COOP 97 Data for July 26, 2023 through July 29, 2023 Click column heading to sort ascending, click again to sort descending. State Name Station Type Highest Max Temperature NJ NEWARK LIBERTY INTL AP WBAN 96 NJ HARRISON COOP 96 NY LAGUARDIA AIRPORT WBAN 95 160 Ave. / Howard Beach 96 Brownsville 95 Corona 99 Lefferts / South Ozone Park 97 Queensbridge / Dutch Kills 96 2021 1920 More 100s back in the old days when the sensor was out in open

Too much moisture and clouds around the region this month. https://www.weather.gov/owp/hdsc_aep https://www.weather.gov/media/owp/oh/hdsc/docs/202307_WestPointNY.pdf

I used dense rank sorting for temperature to compile the top 10. So I came up with 28 months in NYC since 2015 making the top 10 warmest temperatures. This is slightly behind Poughkeepsie which has 35 top 10 warmest months since 2015. My guess is that the tree growth over the NYC ASOS is artificially cooling site. So NYC would probably have closer to POU if the trees were kept at a standard distance from the ASOS like all other sites. Newark is similar to POU also. ………NYC…POU….Top 10 warmest months since 2015 JAN……1…….2 FEB……4……5 MAR…..2……3 APR…..3…….3 MAY….2…….3 JUN….1…….1 JUL….2……5 AUG….4…..5 SEP….2……2 OCT….2…..2 NOV….3….2 DEC…..2….2 NYC…..28 months……POU…..35 months https://www.sqlservertutorial.net/sql-server-window-functions/sql-server-dense_rank-function/

It’s possibly related to the record low Northern American snow cover back in May.

Yeah, you can go into XMACIS2 and run all the top 10 warmest and coldest months at stations around the area. It comes out to something like 1 top 10 coldest temperature month since January 2015 to around 30 top 10 warmest months. Different stations are a little over or under. Each month of the year has had 2-3 top 10 warmest months. This gets multiplied by 12. http://xmacis.rcc-acis.org

These underperforming SE Ridge/ WAR amplifications have become few and far between. The common denominator seems to be when we have near record rainfall in area. My guess is that the ridge usually verifies stronger around 75% or more of the time from 6-10 days out. So this is one of the few times that the models were too warm. Could also be related to the near record blocking this month.

Research Links Climate Change to Lazier Jet Stream, Leading to Extreme Weather BY COLUMBIA CLIMATE SCHOOL |JULY 14, 2023 Comments Jet streams are relatively narrow bands of strong wind in the upper atmosphere, typically occurring around 30,000 feet, and blowing west to east. Their normal flows lead to week-to-week weather variations, modulated in the mid-latitudes by ridges and troughs in the jet stream. A high-pressure ridge, for example, produces clear, warmer weather conditions; a trough is typically followed by stormy conditions. Together, these form waves in the jet stream that can stall as the waves grow and become more amplified, causing “stuck” weather patterns that produce longer storms and heat waves. New research published in Nature Communications describes observations linking increased warming at high latitudes and the ever-decreasing snow cover in North America to these stalls in atmospheric circulation. “These persistent and extreme conditions are thought to be increasing in the future as a result of this increased waviness in the jet stream.” said the study’s lead author Jonathon Preece, a postdoctoral researcher at the University of Georgia. High-pressure ridge over Texas, 2018. (Weatherbell) Since 2000, frequent “stuck” weather patterns have produced heat waves over Greenland, resulting in exceptional melting of the Greenland Ice Sheet. In contrast to these observations, global climate models actually project a slight decrease in the blocked patterns over Greenland and, consequently, the models have underrepresented the contribution of meltwater runoff from the ice sheet to global sea level rise. “These patterns have been consistently creating pulses of melting over the Greenland ice sheet that have been accounting for a large portion of the annual melting,” said study coauthor Marco Tedesco, a professor at Columbia Climate School’s Lamont-Doherty Earth Observatory, and lead principal investigator on the project. “Accounting for such an aspect is crucial for anticipating not only how much but how fast Greenland is and will be contributing to sea level rise.” “One question is whether this is a consequence of climate change that we can expect to continue in the future [that] the climate models are failing to resolve,” said Preece. “Or are the climate models correct, in which case we’d expect things to revert back to the norm and perhaps the rate of accelerated melt of the ice sheet will taper some?” The new study presents evidence of a link to climate change, both in the increases in jet-stream waviness and ever-decreasing spring North American snow cover extent, which “is impacting the atmosphere in a way that is favoring these blocked high-pressure systems over Greenland,” Preece said. Multiple studies have highlighted the discrepancy between climate models and observations. This study provides evidence of a direct connection between the observed shift in summer atmospheric circulation over Greenland and amplified warming at high latitudes. “The new study is the first that we know of that demonstrates a direct link between the observed change in summer atmospheric circulation over Greenland and diminished spring snow cover, which is something we can confidently say is a consequence of climate change,” said coauthor Thomas Mote, a geographer at the University of Georgia. Adapted from a press release by the University of Georgia. Full paper available online with no paywall. https://www.nature.com/articles/s41467-023-39466-6 Abstract The exceptional atmospheric conditions that have accelerated Greenland Ice Sheet mass loss in recent decades have been repeatedly recognized as a possible dynamical response to Arctic amplification. Here, we present evidence of two potentially synergistic mechanisms linking high-latitude warming to the observed increase in Greenland blocking. Consistent with a prominent hypothesis associating Arctic amplification and persistent weather extremes, we show that the summer atmospheric circulation over the North Atlantic has become wavier and link this wavier flow to more prevalent Greenland blocking. While a concomitant decline in terrestrial snow cover has likely contributed to this mechanism by further amplifying warming at high latitudes, we also show that there is a direct stationary Rossby wave response to low spring North American snow cover that enforces an anomalous anticyclone over Greenland, thus helping to anchor the ridge over Greenland in this wavier atmospheric state. Interesting timing with this new study. North America just experienced the lowest May spring snow on record this year. https://climate.rutgers.edu/snowcover/chart_anom.php?ui_set=1&ui_region=namgnld&ui_month=5 The historic spring blocking which greatly reduced the North American snow cover during May could have lead to the extreme blocking and historic SST warmth south of Greenland in July. Which also produced the strong Greenland melt conditions this summer

Newark fell 1° below the warmest spots in NJ. this month so far. Data for July 1, 2023 through July 28, 2023 Click column heading to sort ascending, click again to sort descending. Name Station Type Highest Max Temperature LONG BRANCH-OAKHURST COOP 97 FREEHOLD-MARLBORO COOP 97 HARRISON COOP 97 NEWARK LIBERTY INTL AP WBAN 96 Newark Area ThreadEx 96 ATLANTIC CITY INTL AP WBAN 95 HIGHTSTOWN 2 W COOP 95 ESTELL MANOR COOP 95 AEROFLEX-ANDOVER AIRPORT WBAN 95 Atlantic City Area ThreadEx 95 MANASQUAN 1 NW COOP 95 SEABROOK FARMS COOP 94 NEW BRUNSWICK 3 SE COOP 94 TETERBORO AIRPORT WBAN 94 SOUTH JERSEY REGIONAL AIRPORT WBAN 94 SOMERSET AIRPORT WBAN 94 New Brunswick Area ThreadEx 94 TETERBORO AIRPORT COOP 94 MILLVILLE MUNICIPAL AIRPORT WBAN 93 MOORESTOWN 4 E COOP 93 EWING 3 WNW COOP 93 WERTSVILLE 4 NE COOP 93 FLEMINGTON 5 NNW COOP 93 CALDWELL ESSEX COUNTY AP WBAN 93 PHILADELPHIA/MT. HOLLY WFO COOP 93 EB FORSYTHE NEW JERSEY RAWS 93 PENNSAUKEN 1N COOP 93 CAPE MAY 2 NW COOP 92 TRENTON-MERCER AIRPORT WBAN 92

The magnitude of the historic warm minimums this month in Caribou are a good example of that. Time Series Summary for Caribou Area, ME (ThreadEx) - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Min Temperature Missing Count 1 2023 63.5 4 2 2020 59.9 0 3 1947 59.5 0 4 2018 59.4 0 5 2010 59.2 0 Time Series Summary for Caribou Area, ME (ThreadEx) - Month of Jul Click column heading to sort ascending, click again to sort descending. Rank Year Mean Max Temperature Missing Count 1 2018 82.4 0 2 1952 82.0 0 3 2023 81.5 4 4 1959 81.4 0 5 2019 80.6 0

Another case of the warmer minimums driving the departures higher in the Northeast with the higher dewpoints.

Cedar Rapids is located in a zone of dense agriculture so the effect is well known by the locals. There is nothing wrong with the charts. Ames Iowa shows a similar steep decline since the late 1800s. You can also look at the decrease across the entire state. Des Moines also has a higher population and has a larger urbanized footprint than Cedar Rapids. https://cbs2iowa.com/news/local/special-report-iowas-changing-climate Higher humidity also has impact on temperatures during every season. In summer, average days above 95 degrees in Cedar Rapids from 1894 through 2018 fell by 12.7 days. “We don't seem to have the heat that we used to have when I started back in the 80s and the 70s,” said Weather First Chief Meteorologist Terry Swails. “A lot of temperatures, 98 to 102, that seemed like it was pretty common. It was rare if we went a summer without at least one 100-degree day. Now that's a rare event. It seems if we get 95 that's kind of a big Trend in days above 95 degrees has seen a steep decrease since the late 1800s. Statewide decrease in 95° very hot days. https://statesummaries.ncics.org/chapter/ia/

I agree. The problem with climate change is that the scientific component gets discarded by many since they disagree with the policy remedies being presented. It’s fine to have a civil disagreement about policy since that is what Democratic societies are built on. We have known for ages that adding CO2 to the atmosphere will warm the planet. So this is nothing new. I think the debate in the scientific community isn’t whether it’s happening, but how well we can adapt to the changes in the future. There are optimists that think we can technologically mitigate some of the most extreme climate change scenarios in the future. Others don’t think it will be that easy. Policy presents whole new set of challenges. Much of the expansion of carbon emissions and coal burning is now occurring in Asia. The U.S. has actually seen a small decline in emissions shifting to cleaner natural gas. While places like China are driving the global increase in emissions and opening new coal plants all the time. Then the next debate is renewables vs nuclear. Renewables like wind and solar are very land intensive. So even many people who are conservation minded and care about climate change are fighting large wind and solar installations near their backyards. Plus these energy sources are intermittent and the battery technology for large storage still isn’t there. The power distribution system needs to be upgraded at a great cost to consumers for more Renewables to come on line. Consumers are already stretched and should not have to pay more for their electric. We are seeing increasing debates in places like Germany with soaring electric rates. They are many that advocate for newer nuclear designs but no utilities want to build anymore due to how high the coast of building a new nuclear plant has become. So the global default may be to continue with business as usual increases in emissions while tying to innovate our way out of the damage that it’s causing the planet. What may happen is that wealthier countries will find ways to cope. But large stretches of the planet especially closer to the equator will really suffer. Not to mention the impact on wildlife which can only adapt or migrate so fast.

The cooling effect from the expansion of agriculture and irrigation is most pronounced in the long term decline in very hot 95° and higher days across the region. https://cbs2iowa.com/news/local/special-report-iowas-changing-climate Higher humidity also has impact on temperatures during every season. In summer, average days above 95 degrees in Cedar Rapids from 1894 through 2018 fell by 12.7 days. “We don't seem to have the heat that we used to have when I started back in the 80s and the 70s,” said Weather First Chief Meteorologist Terry Swails. “A lot of temperatures, 98 to 102, that seemed like it was pretty common. It was rare if we went a summer without at least one 100-degree day. Now that's a rare event. It seems if we get 95 that's kind of a big deal.”

These strong south based blocks continue to become more common. We could have used this more +PNA back in December. Turned out to be a record setting wet pattern in spots with the energy getting stuck under the block.

I was able to find a few longer term observations from the shallower Florida Bay on twitter.

Too wet this month with all the convection and clouds to build the 100° heat like last July.

Strongest Ambrose Jet of the season today with gusts 35-40 mph near the shore. Plenty of rip currents and very rough surf. Blowing sand will be common also.

Nice under 10 minute presentation on the topic today.

Another extreme marine heatwave for the planet under a near record 500 mb blocking pattern for July in that part of the world. We had another near record 500 mb anomaly last December just north of that location.

A little late in the month for the warmest day based on previous years. https://mesonet.agron.iastate.edu/plotting/auto/?_wait=no&q=65&network=NJCLIMATE&station=NJ6026&month=7&dir=hot&_r=t&dpi=100&_fmt=png Time Series Summary for NEWARK LIBERTY INTL AP, NJ Click column heading to sort ascending, click again to sort descending. Ending Date Highest Max Temperature Jul 27 to Jul 31 Missing Count 2022-07-31 92 0 2021-07-31 94 0 2020-07-31 96 0 2019-07-31 95 0 2018-07-31 89 0 2017-07-31 91 0 2016-07-31 93 0 2015-07-31 96 0 2014-07-31 90 0 2013-07-31 87 0 2012-07-31 90 0 2011-07-31 95 0 2010-07-31 93 0

The corn belt is located more over Eastern SD. But I just bring up to add as one factor out of several including ENSO teleconnections. There are several layers to a hemispheric Rossby wave pattern. Whether the Corn Belt cooler and wetter influence is working to alter the background Rossby wave pattern is still an unknown. We have several examples when the influence is warmer instead of cooler. It could also be working on a level to cool further what would have already been a cooler El Niño teleconnection pattern for the Plains. So would need a model study to isolate possible influences in the overall upper pattern. In any event, those extreme dust bowl heat records should be safe for another July.