Roger Smith

Ranking tables normally account for ties and the case mentioned would be 11th warmest, after five tied at 6th warmest. It would not or at least should not be ranked seventh warmest. Some tables including CET differentiate by second decimals not visible in the table. The apparently tied months are marginally separated by these unprinted second decimals. In some ranking tables, it is up to you to establish ties, the table may be printed without ties identified. Most commonly, that kind of table will have the tied years listed in chronological order. But with everyone tweeting their own versions of climate stats, it is wise to find out whether they respect conventional ranking protocols or not. Also a top ten from a record of thirty years is obviously a bit easier to establish than a top ten from 155 years like NYC or 183 like Toronto. Another source of minor confusion in at least one prominent set of ranks (CET) is the practice of leaving the warmest rank blank until it happens, for example, this is what you see if you click on monthly ranks for CET ... at the bottom of the rankings where they place the warmest months, you find 1st (ranks on right, the ranks on left are in the sense of coldest of 355 in their records) blank for July to December ... further up the table you need to remember that what appears to be 40th warmest August is actually 39th warmest August. (EXCERPT of CET monthly rankings) 355 6.5 1686 6.9 1961 8.0 2022 10.2 1796 13.5 1868 16.4 1818 18.4 1808 18.0 1990 15.6 1780 12.5 1968 8.9 1881 7.3 1857 10.6 1990 11 356 6.6 1898 6.9 2019 8.1 1734 10.2 1944 13.5 1919 16.6 1775 18.4 2013 18.1 1955 15.6 1999 12.6 1959 9.1 1817 7.3 1988 10.6 1999 10 357 6.7 2008 6.9 2022 8.2 1750 10.3 1987 13.5 1947 16.8 1858 18.5 1995 18.2 1911 15.7 1760 12.7 1831 9.2 2022 7.4 1843 10.6 2017 9 358 6.7 1983 7.0 2002 8.2 1961 10.3 1893 13.5 1784 16.9 1798 18.5 1921 18.3 1747 16.0 1795 12.7 1995 9.2 1730 7.4 1828 10.6 1949 8 359 6.8 1975 7.1 1903 8.3 1990 10.3 2014 13.6 1992 16.9 1976 18.6 1976 18.3 2003 16.0 2021 12.8 1921 9.3 1743 7.5 1710 10.7 2018 7 360 6.9 1733 7.1 1945 8.3 1948 10.3 1798 13.6 1727 16.9 1762 18.7 1852 18.6 1947 16.1 2016 12.8 2022 9.4 1938 7.6 1733 10.7 2011 6 361 7.0 2007 7.2 1794 8.4 2012 10.5 1943 13.7 1808 17.0 2023 18.8 1783 18.6 1975 16.3 1949 12.9 2006 9.4 2015 7.7 1852 10.8 2020 5 362 7.1 1834 7.2 1998 8.4 1997 10.5 2020 13.8 1788 17.1 1822 19.2 2018 18.7 2022 16.3 1865 13.0 2005 9.5 1818 7.9 1974 10.9 2006 4 363 7.3 1796 7.3 1990 8.8 2017 10.6 1865 13.8 1758 17.3 1826 19.4 1983 19.0 1997 16.6 1729 13.1 1969 9.5 2011 8.1 1934 11.0 2014 3 364 7.3 1921 7.5 1869 9.1 1938 11.3 2007 13.9 1848 18.0 1676 19.8 2006 19.1 1995 16.9 2006 13.2 2001 9.9 1994 9.6 2015 11.1 2022 2 365 7.6 1916 7.9 1779 9.2 1957 11.9 2011 15.1 1833 18.2 1846 --- 2023 --- 2023 --- 2023 --- 2023 --- 2023 --- 2023 --- 2023 1

I am only seeing 96 at BWI, 97 at DCA is the lone increase today. Scoring table will be adjusted.

According to my stats, since the top ten cold month of Feb 2015, these top ten warm months have been recorded at NYC, near miss 11-15 cases shown in ((( triple brackets ))) ... these are not adjusted for urban heat island, some of these ranks would fall slightly if a progressive u.h.i. adjustment was applied ... : JAN _ 1 (2023) ... (((12 2020))) FEB _ 1 (2018) .. 2 (2017) .. 3 (2023) .. t8 (2020) MAR _ 4 (2016) .. 7 (2020) .. (((t13 2021))) APR _ 2 (2023) .. 3 (2017) .. (((t13 2019))) MAY _ 2 (2015) .. 6 (2018) JUN _ t6 (2021) JUL _ 7 (2020) .. ((( t11 2019, t13 2022 ))) AUG _ 3 (2022) .. 4 (2016) .. 5 (2015) .. t10 (2018) SEP _ 1 (2015) .. t10 (2016) OCT _ 1 (2017) .. 6 (2021) NOV _ 1 (2020) .. 2 (2015) .. (((13 2022))) DEC _ 1 (2015) .. t3 (2021) ________________ That is a total of 25 top ten months and 31 top 15. Feb 2015 was third coldest and since then the highest ranking cold month is t31 coldest Nov 2019.

Current standings as of July 29, 2023 Table remains in forecast table order for now. Errors underlined are the few that are forecasts already passed by actual maxima so far. __ Max values to date ____________ 97 __ 98 __ 97 __ 98 The qualifier for rank is the separation of equal error totals by the rules outlined earlier. This table will be adjusted if or when necessary, and if not, it will be posted again in rank order later in the summer. (table adjusted July 29 for DCA 97) FORECASTER (order of entry) __ DCA _ IAD _ BWI _ RIC _____ Errors ____Total __ Rank __ qualifier (to separate tied totals) GeorgeBM ( 8 ) _________________ 105 _ 103 _ 106 _ 104 ______ 8 5 9 6 ___ 28 ____ 26 StormchaserChuck1 ( 1 ) ________ 104 _ 103 _ 103 _ 104 ______7 5 6 6 ___ 24 ____25 Roger Smith _____________________ 102 _ 102 _ 103 _ 103 ______5 4 6 5 ___ 20 ____ 23 H2O (20) _________________________102 _ 101 _ 102 _ 102 ______ 5 3 5 4 ___ 17 ____20 __ 2nd lowest error (3) ChillinIt (15) ______________________102 __ 98 _ 103 _ 104 ______ 5 0 6 6 ___ 17 ____19 __ lowest lowest error (0) Rhino16 ( 2 ) _____________________ 101 _ 103 _ 102 _ 105 ______ 4 5 5 7 ___ 21 ____24 mattie g (17) ______________________101 _ 103 _ 101 _ 102 ______ 4 5 4 4 ___ 17 ____21 __ highest lowest error (4) wxdude64 (16) ___________________101 __ 99 _ 101 __ 102 ______4 1 4 4 ___ 13____ 17 __ lower lowest error (1) soundmdwatcher (23) ___________ 100 _ 102 _ 104 _ 102 ______3 4 7 4 ___ 18 ____22 Terpeast ( 6 ) ____________________ 100 _ 101 _ 101 _ 100 ______ 3 3 4 2 ___ 12 ____16 __ higher lowest error (2) tplbge (24) _______________________100 _ 100 _ 102 _ 101 ______ 3 2 5 3 ___ 13 ____18 __ higher lowest error (2) GramaxRefugee (19) _____________100 __ 99 _ 100 _ 100 ______ 3 1 3 2 ____ 9 ____10 __ later entry toolsheds (18) ____________________100 __ 98 _ 101 _ 102 ______ 3 0 4 4 ___ 11 ____14 biodhokie (25) ____________________ 99 _ 101 __ 99 _ 101 ______ 2 3 2 3 ___ 10 ____13 __ higher lowest error (2) RickinBaltimore ( 7 ) ______________ 99 __100 _ 100 __ 99 ______ 2 2 3 1 ____ 8 ____ 8 WinstonSalemArlington (22) ______ 99 __ 99 _ 103 _ 101 ______ 2 1 6 3 ___ 12 ____15 __ lower lowest error (1) nw baltimore wx ( 3 ) _____________ 99 __ 99 _ 101 _ 100 ______ 2 1 4 2 ____ 9 ____ 9 __ earlier entry Weather53 (13) ___________________ 99 __ 99 _ 100 _ 101 ______ 2 1 3 3 ____ 9 ____11 __ higher second lowest error (3 vs 2 for 9th, 10th) WxUSAF ( 4 ) _____________________ 99 __ 99 _ 100 __ 99 ______ 2 1 3 1 ____ 7 _____ 7 __ higher lowest error (1) katabatic ( 9 ) _____________________99 __ 98 _ 100 _ 100 ______ 2 0 3 2 ____ 7 _____ 6 __ lower lowest error (0) NorthArlington101 (21) ____________ 99 __ 97 __ 99 __ 99 ______ 2 1 2 1 ____ 6 _____ 4 __ later entry Stormpc (14) ______________________98 _ 102 __ 101 __ 99 ______ 1 4 4 1 ___ 10 ____12 __ lower lowest error (1) MN Transplant ( 5 ) _______________ 98 __ 99 _ 100 __ 99 ______ 1 1 3 1 ____ 6 _____ 3 __ earlier entry Its a Breeze (12) __________________ 98 __ 99 __ 99 _ 100 ______ 1 1 2 2 ____ 6 _____ 5 __ higher second lowest error WxWatcher007 (11) _______________ 98 __ 97 __ 99 __ 99 ______ 1 1 2 1 ____ 5 _____ 2 LittleVillageWx (10) _______________ 98 __ 97 __ 98 __ 98 ______ 1 1 1 0 ____ 3 _____ 1

Three locations tied the above values (previous post) and RIC went to 98F on July 28. Edited previous post. edited again July 29 for DCA 97F. IAD added another tied 98F.

DCA slagged for a low temperature report? Now we've seen everything. DonS, have you been following Mediterranean heat wave. I think it peaked around Monday-Tuesday with quite a few locations near all-time record highs. One example, Catania on east coast of Sicily, 45.6 C (all-time record high 46.0). Some locations in Tunisia may have exceeded all-time records near 49 C (120F). Similar setup to Arizona heat wave, the heat tries to move north but so far this summer central and northern Europe have remained relatively temperate. British Isles had warmer June than July for first time since 1970 and it wasn't even close, CET 17.0 June then around 16.1 for July. It was fifth warmest June on record in Britain, and warmest since 1846. All four warmer years were well back, 1846, 1826, 1676 and 1822 were warmer. June is the only month in the CET series with records mainly confined to pre-modern warming era although May is almost the same and its warmest month was 1833. The twelve months in CET (which spans 1659 to present) have these years as warmest on record: Jan 1916, Feb 1779, Mar 1957, Apr 2011, May 1833, June 1846, July 2006, Aug 1995, Sep 2006, Oct 2001, Nov 1994, and Dec 2015. The warmest year was 2014. The warmest day was last July 19th. June 1676 is the only "Maunder month" to crack any top five and in general the Maunder minimum period is about a Celsius degree colder than the overall average and almost 2 C colder than recent 30-year averages. Before this modern warming era, 1721 to 1739 was a relatively warm interval, and 1818 to 1834 was often quite warm despite some cold winters.

Popping in to remind the usual suspects to enter the August temperature forecast contest over in the sleepy realm of the general weather forum. I don't know if there's an admiral weather forum.

Naturally interested in these data summaries, see my Toronto and New York City data analyses in the climate change forum here. If somebody can post links to all similar data for Chicago I could work up simiar tables. FWIW my urban heat island assessment for Toronto is an average increase of 1.1 C or 2.0 F occurring in 0.1 C increments per decade, starting with 1881-1890 when the city began to surround the location of the now-downtown (but originally edge of town) university campus location. Of course this is an average for different situations, a cool, dry month with a lot of clear nights would have a larger differential than a humid, wet month. I have applied the same set of adjustments to NYC data with the assumption that a larger heat island of 1.4 C began to appear before NYC data started in 1869. That makes the period 1869 to 1880 if unadjusted, 0.2 C warmer, and the first decade adjusted for Toronto 0.3 C warmer (1881-90). But as the data are only being ranked against each other, those additional adjustments make no difference to ranking outcomes. Is there a link to daily records, and if so, would ORD have incorporated older records from a different location? If not, is there a set of daily records that does span a longer interval? As it happens, it took only four days for Toronto to establish its first daily record (March 4th, 1840) that has somehow managed to persist to the present time. There are very few others on the warm side that lasted very long. One factor for Toronto is that a cooling lake breeze could more easily reach the location of the downtown weather station before the advent of multi-storey buildings around 1900. This wall of skyscrapers nowadays is a real inhibiting factor and the lake breeze tends to make better progress inland on either side of downtown Toronto. I suppose for Chicago the frequency of cooling lake breezes would be lower given the wind directions involved. Toronto is quite often in a south to east wind flow in spring anyway so the lake breeze is quite often a factor there.

Update ... DCA __ 97 on July 29 IAD ___ 98 on July 27, 28, 29 BWI ___ 97 on June 2 and July 27, 28 RIC ___ 96 on July 27 then 98 on July 28 Made several updates to July 29 ...

Predict temp anomaly (F deg) relative to 1991-2020 average, for DCA _ NYC _ BOS __ ORD _ ATL _ IAH ___ DEN _ PHX _ SEA deadline 06z Tuesday August 1st. No assembly required. State and local taxes may apply. Co-pay available.

Good chance of near 100F on Friday? One day wonder. If that southwest heat wave ever got fully released ... but it looks like a brief blast from that source as the southwest heat dome connects briefly to the distant Atlantic ridge. May last into Saturday for RIC possibly.

Touch and go whether the severe heat makes it into NYC or gets cut off around central NJ on Friday but what looks more certain is a chance of severe storms on Saturday as a strong wave forms around Ohio and moves towards n NJ and NYC. My guess is something like 95-100F in central NJ on Friday, 92-95 F at NYC airports, 85-90 at ISP and POU then 2-3" rain potential (hit or miss probably) across the region on Saturday. The southwest heat dome is currently at 600 dm over NM and is supposed to start deflating gradually over next five days to the low 590s allowing more of a typical monsoon mid-summer pattern to replace the magnifying glass effect. By this weekend there could be some monsoon storms forming over AZ. I notice the heat has moved as far north as the southern tier of counties in Nebraska but not so much beyond that, Omaha was only into the mid-80s while Topeka was 102. That is probably a precursor of a similar sharp gradient with the heat as it makes its one or two day presence felt further east, but the southwest ridge and the Atlantic ridge never make much of a connection before it all collapses this weekend. With that heavy rain potential on Saturday, temps could be between 75 and 80 during the rain but highs could reach 85-90 in any sunshine.

As of today, summer max ... ... DCA __ 94 on June 2 and July 13 IAD ___ 96 on July 13 BWI ___ 97 on June 2 (96 on July 13) RIC ___ 94 on July 4, 13

Remains to be seen where 2023 may fit into this summary: MAXIMUM TEMPERATURES of YEARS 1869 to 2022 106 _ 1936 104 _ 1918, 1977, 2011 103 _ 1948, 1966, 2001, 2010 102 _ 1930, 1933, 1944, 1949, 1953, 1980, 1991, 1993, 1995 101 _ 1881, 1934, 1957, 1999 100 _ 1898, 1901, 1911, 1917, 1926, 1937, 1952, 1954, 1955, 2012 99 _ 1885, 1919, 1923, 1924, 1925, 1929, 1931, 1943, 1956, 1962, 1964, 1983, 1988, 2005 98 _ 1876, 1879, 1890, 1891, 1896, 1940, 1941, 1963, 1968, 1973, 1975, 1982, 1986, 1994, 2002, 2013, 2021 97 _ 1892, 1895, 1900, 1912, 1942, 1945, 1959, 1961, 1969, 1987, 1997, 2006, 2015, 2022 96 _ 1872, 1880, 1887, 1888, 1894, 1905, 1908, 1921, 1932, 1938, 1939, 1967, 1971, 1976, 1981, 1984, 1989, 1996, 2008, 2016, 2018, 2020 95 _ 1869, 1883, 1893, 1899, 1903, 1913, 1914, 1916, 1935, 1947, 1950, 1965, 1974, 1978, 1979, 1985, 1990, 2019 94 _ 1870, 1873, 1878, 1886, 1904, 1906, 1910, 1915, 1920, 1922, 1928, 1946, 1951, 1970, 1972, 2003, 2017 93 _ 1874, 1875, 1882, 1897, 1909, 1958, 1992, 1998, 2000 (2023 so far) 92 _ 1871, 1877, 1907, 1927, 2007, 2009, 2014 91 _ 1884, 1889, 1960, 2004 90 _ 1902

__ Final scoring for July 2023 __ ... scoring based on end of month anomalies reported in previous post ... ^ indicates max 60 scoring for PHX. ____________________________ DCA_NYC_BOS__east__ORD_ATL_IAH__cent_ c/e __ DEN_PHX_SEA__west __ TOTAL wxallannj ____________________92 _ 94 _ 98 __ 284 __ 86 _ 76 _ 80 __ 242 _ 526 __100_ 36^_ 84 __220 ____ 746 RJay _________________________82 _100 _ 96 __ 278 __ 66 _ 86 _ 96__ 248 _ 526 __26 _ 60^_ 98__ 184 ____ 710 DonSutherland1 _____________ 86 _ 94 _ 92 __ 272 __ 94 _ 76 _ 70 __ 240 _ 512 __ 92 _ 24^_ 78 __ 194 ____ 706 BKViking _____________________ 92 _ 88 _ 92 __ 272 __ 84 _ 74 _ 86 __ 244 _ 516 __ 32 _ 54^_100__186 ____ 702 ___ Consensus _______________ 94 _ 88 _ 88 __ 270 __ 92 _ 74 _ 78 __ 244 _ 514 __ 56 _ 27^_ 92 __ 175 ____ 689 wxdude64 ____________________74 _ 66 _ 70 __ 210 __ 98 _ 70 _ 82 __ 250 _ 460 __ 96 _48^_ 80 __ 224 ____ 684 hudsonvalley21 ______________ 98 _ 86 _ 96 __ 280 __ 92 _ 74 _ 66 __ 232 _ 512 __ 60 _ 12^_ 96 __ 168 ____ 680 Scotty Lightning _____________ 92 _ 90 _ 84 __ 266 __ 96 _ 76 _ 76 __ 248 _ 514 __ 66 _ 24^_ 72 __ 162 ____ 676 Tom _________________________ 98_ 88 _ 84 __ 270 __ 84 _ 68 _ 70 __ 222 _ 492 __ 54 _ 06^_ 84 __ 144 ____ 636 RodneyS _____________________ 80 _ 76 _ 76 __ 232 __ 68 _ 52 _ 86 __ 206 _ 438 __ 52 _ 42^_ 98 __ 192 ____ 630 Roger Smith __________________94 _ 76 _ 76 __ 246 __ 98 _ 42 _ 76 __ 216 _ 462 __ 46 _ 24^_ 72 __ 142 ____ 604 ___ Normal ___________________ 88 _ 70 _ 74 __ 232 __ 94 _ 56 _ 46 __ 196 _ 428 __ 76 _ 00 __72 __ 148 ____ 576 ___ Persistence (June anoms) ____ -2.2 _ -2.0 _-2.1 ____ ____ +0.2 _-1.3 _+2.1 ____ ____ ____ __ -4.0 _-2.0* _ 0.0 ___ Persistence scoring _______44 _ 30 _ 32 __ 106 __ 98 _ 30 _ 88 __ 216 _ 322 __ 44 _ 00 _ 72 __ 116 ____ 438 ____________________________ EXTREME FORECASTS DCA, BOS, SEA do not qualify for an extreme forecast. (BOS and SEA missed by 0.1 as 3rd warmest forecasts were top scores) NYC, ATL, IAH and PHX are wins for RJay warmest forecasts. ORD is a shared win for wxdude64 and Roger Smith, and a loss for RodneyS (also a loss for Normal) with coldest forecast. DEN is a win for second coldest forecast (wxallannj) and a loss for coldest wxdude64.

A lot depends on site characteristics for airport weather stations. If the instruments are close to tarmac and parking lots, those might be larger factors than urban heat island if the airport is not surrounded by urban areas. Shannon airport in Ireland is essentially a rural location but Irish weather folk seem to believe it has a 1 C bias in hot weather due to the instruments being very close to tarmac and parking lots. DCA is another such location. I would imagine that Phoenix would be running near 118F even if there was no human presence, in this weather pattern, but the nights might not be quite as warm maybe? A good station to check for long-term unaffected (by urban effect) trends might be Bryce Canyon airport in Utah or Canyonlands airport near Moab. Neither of those locations has a very large airport around, and they are miles out of town (for Bryce Canyon, the nearby urban locations are all very small, Panguitch UT might have a tiny heat island; for Moab, Canyonlands is ten miles out of town and Moab itself probably has a very small heat island. Another location with no heat island potential would be hanksville UT which is east of Capitol Reef NP. The village is just a few houses and a gas station and motel, it would not have an urban heat island at all.

(edit for Don reaching hurricane status ...) For the contest, the count is now 5/1/0 ... here's an overview of storm names un-named Jan storm, Arlene, Bret, Cindy _ done (4/0/0) Don __ now present, becoming a hurricane on July 22nd. (5/1/0) possible storm names to come: Emily, Franklin, Gert, Harold, Idalia, Jose, Katia, Lee, Margot Nigel, Ophelia, Philippe, Rina, Sean, Tammy, Vince, Whitney

Two points about July (and August) 1936, the heat was definitely more persistent in the central plains than the eastern regions, but that week when the heat spread east was brutally hot and both daytime and overnight high min records were widespread. People were sleeping outdoors all over the affected regions for at least several consecutive nights to avoid heat prostration. No matter what the rest of the month felt like, that week would have prompted a major media and political response (back then it was just media, FDR had enough to do without trying to fix the weather). Also it was a year to year recurring pattern to some extent, every summer 1933 to 1937 had some brutal heat waves. The other point would be that many seem to think we caused the 1930s heat waves by poor agricultural practices in the great plains region. I doubt this is true (while I don't disagree there were poor practices). The atmosphere would have created those severe heat waves anyway, our contribution to it was probably on the order of the last degree possibly. (so 104/77 instead of 105/78 at Toronto for example). In the roundup of how locations fared relative to monthly normal, no normal was shown for Toronto but that monthly value was actually about 2F (or 1 C) above the 1901-30 average and slightly above more recent averages. July 1936 was t27 warmest of 183 years (with five other years, at 22.9 C) but obviously if the period July 7-14 had persisted all month it would have easily been warmest on record, which at this point is 25.5 C (1921) closely followed by 2021 (25.4 C). Those stats are all uncorrected for urban heat island but 1936 (reduced to 22.3) only moves up very slightly to t25 warmest in my estimates. Also it had a similar mean to several other July outcomes in the 1930s. Some of those months had longer hot spells but they were less intense. July 1932 was quite a cool month but all summers from about 1929 to 1941 had significant heat waves at some point, then 1942 had the very heavy rainfalls mid-July that Sacrus mentioned in his daily historical update. These were less extreme in Ontario but did set some daily records there too. Now there's another past weather event that would have been very volatile in today's political environment, 30.6" of rain in six hours! I have seen 6" of rain in six hours in Ontario (in Aug 1976 and from hugo's remnant low in Sep 1989) and it was pouring non-stop, cannot imagine five times as much falling. At NYC, July 1936 was very close to the overall median at t75 warmest out of 154. So relative to Toronto it had a cooler month. That also remains close to the median with u.h.i. adjustment (t75 again). Toronto ranks also improve by one (to t26, t24) in the same data set because a hot July in 1868 is dropped from the direct comparison (NYC began in 1869). The continental influence in this case was considerably stronger. Other summers with large variations in ranks include 1916, 1919, and 1921. But many years have very similar ranks at both locations. Anyone interested in seeing all this data can find it all here: (our climate change forum, and also this link where excel files are posted, they are too large to fit here ... https://www.community.netweather.tv/topic/93113-toronto-180-a-north-american-data-base-of-182-years-now-includes-nyc-1869-2022/page/2/ My feeling is, if 1911 and 1936 could produce multiple consecutive scorchers in the 101-110 range, then there's no reason to suppose that years like 1977, 1988 and 2012 (which you could argue were similar) represent the upper limit of what could be experienced in future years, and after the unprecedented heat dome hit my present location in June 2021, I am certainly well aware that previous upper limits can be not just edged out but pushed aside rather brutally. We had three days here that broke all-time previous records. Even without us heating up the atmosphere, natural variability can do the same and no doubt it will happen, sooner or later, that 1936 will have to step aside (a sobering thought). The whole point of the discussion (to call it a debate would be perhaps over-stating) is that we have not really worked out whether or not our modification of the atmosphere is creating different dynamics or just warming up the old dynamics. For example, the heat dome was basically a 599 dm high with 588 dm thicknesses acting like a magnifying glass over our region. Now the question is, without an advanced human economy present, would that have happened anyway, and stopped 1-2 F deg short without the added ghg, or did we add dm to those disturbing numbers? In 1936 I would imagine the upper dynamics were at least equal to those and probably a bit higher. I have read about nearly equal western heat waves way back in 1898 as well as 1941. So my hunch is, we are not creating these dynamics, we are just adding a bit of heat to them. Perhaps it's a bit of both.

If the 1936 heat wave happened this year, can you imagine the political response? Or that scorcher at the end of August into September 1953? I'm seeing this warming climate as largely a bump up in overnight temperatures and a very slight increase, if any at all, in daytime readings. The main change is, we don't get those cooler spells with clear and very cool nights as often, and it takes some sort of major anomaly in the upper flow to create one at all. This seems to be the case all over the hemisphere and not just in the eastern U.S., people in the British Isles notice the same pattern, although relatively speaking, they seem to be getting more and more intense heat waves too. I don't think the records show that to be the case in North America. What some call global warming, I call global blanding. The frequency of bland weather patterns is certainly increasing. They tend to have quite warm nights and so-so daytime warmth. Now some believe that severe weather is increasing, I view it more as steady-state. You can cherry pick data either way to show it increasing or decreasing, but on the whole, I don't see obvious trends of increasing severe weather (excluding temperature related severe weather). For both hurricanes and tornados, the biggest outbreaks or events are often well back in the past. Of course one has to factor in improvements in forecasting and warnings, and public awareness. I would not want to mis-represent by throwing in death toll data from past events, not as many people would die today, especially if you removed population increases in the path of these most powerful events. But even so, flooding rainfalls, severe windstorms, tornado and hurricane -- none of these is really on the increase, and in fact you would expect them to decrease slightly if air mass contrast was less intense (as is obviously the case in the warmer climate). I think there are probably more forest fires in recent decades but perhaps a return to a reality which existed before, the anomalous period may have been something like 1950 to 1985 with fewer fires. When you read historical accounts of the 1910-1940 period in western regions, there were numerous references to thick smoky haze from forest fires. It has to be kept in mind that they did not attempt to suppress them back then. On the other hand, there were fewer severe fire seasons around the 1960s and 1970s. This modern era of frequent fires seems to have begun to ramp up in 1988, the year of widespread heat waves and the severe Yellowstone region fires. Some other bad western fire seasons were 1998, 2003, 2009 and 2018. A problem is separating out human caused fires from naturally occurring fires. Some of the human caused fires are deliberate arson, for various reasons including a desire to get work, a mental illness problem (for example, a desire for recognition, either directly as in an arrest, or indirectly as in people seeing the results, a forest on fire), or even a misguided political motive (accelerate the political process by producing the claimed results of global warming -- it happens, court cases prove it). Other human caused fires are accidental, at least to the extent that you can call tossing a butt into a dry forest an accident (to my mind it amounts to arson), or parking a very hot car engine over dry grass (then the person leaves, not realizing they have left behind a slowly spreading ground fire). Unattended campfires in windy weather can be a big problem also.

I don't strongly disagree with any of the points raised. just trying to assess the most accurate intensity of urban heat island components of recent warming trends. Anyway, the OP started this thread to have a discussion of natural variability which continues to exist and which modulates the climate as it warms. So I would hope we can return to that focus and discuss that 11-year signal in summer temperatures in NYC which I would assume would probably apply to a much larger region of eastern and perhaps central North America.

To the earlier post, urban heat island is definitely a real phenomenon, you can measure its strength by driving a mobile thermometer through the urban-rural boundary on a clear night. The concept of reducing urban temperature series by subtracting u.h.i. is not a skeptic dodge as perhaps implied, but in fact is practised by even the UK Met Office with the CET series. Nobody would ever accuse them of being skeptics. I've already said I am not a skeptic, I just want to establish what's actually happening and why. I don't doubt that there is a significant human warming signal. I do doubt that we fully understand how it takes place, but I do think it is largely understood, just a matter of ironing out some details. I don't think anybody (here at least) is arguing that urban heat islands are being confused with AGW. The argument is more subtle. Maybe AGW has an escaped urban heat component, when the heat islands dissipate heat during windy weather, it enters the larger atmosphere. That however does not make it different from human-caused, it's more of a question of exactly how humans are causing the AGW signal. It might not lead to any different conclusions about mitigation.

Thanks, maybe a repeat of the 1893-94 peak which was a bit stronger than either 1883 or 1905(-07) within that particular downturn. By the way, if you can edit your post, "Universal Time" should be Year, no?

Note also, if that cycle has a solar variation connection, the solar cycles were longer from 1870 to 1905 than during the stronger regular cycles of the 20th century, and you'll note that 1876 (year 8), 1887 (year 8), 1899 (year 9) are all warm peaks rather than year 10 in those first three periods. Using them would create an average a little over 24.0 C and would yield an overall cycle of 11.2 years which might begin to manifest again if we get a few consecutive weak solar cycles separated by 12-13 years (like 1870, 1883, 1893, 1905, 1917). Solar maxima since 1917 have been 1928, 1937, 1947, 1957, 1968, 1979, 1989, 2001, a double weak peak 2012-15, and the current developing peak expected to hit maximum in 2024-25. The pattern of solar activity has been generally following a trend of 5-8 regular strong cycles about ten years apart, separated by 2-4 weaker cycles 12-14 years apart. The Maunder minimum was a longer and more profound lack of activity, otherwise, according to Schove's index based on auroral reports before the observational age began around 1610, the Sun has been behaving in those irregular two-phase modes. Stronger cycles occurred 1718-1787 and 1838-1870. The interval between those is known as the Dalton minimum. Other strong pulses of solar activity are believed to have occurred in the 14th and 16th centuries. Much of the 15th century generated weaker activity and is known as the Sporer minimum. The shallower minimum including the 1883, 1893 and 1905 peaks does not have a widely accepted name, perhaps it could be called the Edison minimum or the Curie minimum. It was in fact almost identical to the Dalton (peaks 1801, 1816, 1829) if perhaps 10 to 20 per cent more active. This current downturn is often called the Gleissberg minimum and so far is keeping pace with the Dalton and "Edison/Curie" episodes. It has not turned out to be Maunder 2.0 as some had predicted or speculated. It is a bit stronger than the Sporer minimum also. Now, it's quite possible this 11-year temperature cycle has no connection to solar activity at all. I do not have ready theories as to what else could cause it (and note, it is not my claimed discovery either, it has been widely discussed here for years). If it is a multiple of a shorter cycle (for example, 5 x 2.2 yr, 4 x 2.75 yr, 3 x 3.67 y or 2 x 5.5 years) then its other peaks would avoid summer months when they hit. That might be one avenue of investigation.

I promised to post some material about natural variability in the atmosphere. First, a disclaimer, I would not call myself an AGW skeptic nor am I in the forefront of AGW research. My belief is that temperatures are trending upwards and a portion of that increase is due to AGW, another portion due to natural variability. I believe that the components are approximately equal. I am aware that the IPCC holds a different view, namely that all of the recent increases are due to AGW and without a developed human civilization we would now be in a slightly cooling natural climate. In any case, my interest is more along the lines of trying to establish what natural variability can be expected and then to try to separate out an AGW signal from those conclusions. I don't perceive that AGW proponents or researchers discount the existence of natural variability, but they may assume it is a series of ups and downs against that supposedly slightly cooling natural climate regime. Before we could have any hope of a decision about who would be right or wrong about relative size of AGW and natural warming (if any), we would need to know with some assurance what natural variations should be occurring and then compare that with actual trends. The difference would presumably be the actual AGW signal. Nor do I discount the possibility that a natural cooling signal could begin to occur at any time given that we are now two cycles into a lower energy solar variability regime. _______ _______ The first natural cycle I will examine is the often mentioned 11-year cycle of summer heat which proponents point out tends to peak in years that are multiples of 1900+11n (1900, 1911, 1922, 1933 etc). What is the truth of this assertion, and if any truth, what might be a potential cause of it? First of all, to present a raw data measurement of this cycle, I have turned to my data base discussed in another thread here on the climate change forum, the Toronto and NYC historical data series and analysis. From that, I have extracted mean summer temperatures (June to August) for NYC. My data is converted to Celsius. This is the data table for summers in the NYC record (1869 to 2022). I show the average values of all eleven years in the cycle. Since 1869 is two years after 1867, a back-extension year of the cycle, this table places the multiples of 11 summers in column ten out of eleven. TABLE: MEAN SUMMER TEMPERATURE FOR NYC ARRANGED FOR ANALYSIS OF 11-YEAR CYCLE 1869 to 2022 Cycle ______________________________________________________________________________________________ (1900+11n) ________ begins ______ Year 1 __ Year 2 __ Year 3 __ Year 4 __ Year 5 __ Year 6 __ Year 7 __ Year 8 __ Year 9 __ Year 10 __ Year 11 __ 1869 _____ 21.83 ___ 23.85 ___ 21.87 ___ 23.76 ___ 22.54 ___ 21.91 ___ 22.24 ___ 24.46 ___ 23.07 ___ 22.90 ___ 22.44 __ 1880 _____ 23.09 ___ 21.61 ____23.15 ___ 22.76 ___ 22.39 ___ 23.31 ___ 21.67 ___ 22.56 ___ 21.89 ____ 21.91 ___ 22.20 __ 1891 _____ 22.83 ___ 23.46 ___ 22.08 ___ 22.22 ___ 23.17 ___ 23.46 ___ 22.33 ___23.45 ___ 23.98 ___ 23.54 ___ 23.57 __ 1902 _____ 21.39 ___ 20.72 ___ 22.56 ___ 23.21 ___ 24.41 ___ 22.85 ___ 24.56 ___ 22.56 ___ 22.57 ___ 23.00 ___ 22.43 __ 1913 _____ 22.96 ___ 22.15 ___ 21.76 ___ 22.20 ___ 23.41 ___ 22.76 ___ 22.42 ___ 22.46 ___ 22.98 ___ 22.57 ___ 22.93 __ 1924 _____ 22.26 ___ 23.18 ___ 22.20 ___ 21.07 ___ 22.72 ___ 23.05 ___ 23.61 ___ 23.59 ___ 23.57 ___ 23.53 ___ 23.61 __ 1935 _____ 23.33 ___ 23.22 ___ 23.89 ___ 23.91 ___ 24.39 ___ 22.59 ___ 23.28 ___ 23.13 ___ 24.63 ___ 24.72 ___ 22.76 __ 1946 _____ 22.22 ___ 22.94 ___ 23.30 ___ 24.92 ___ 22.67 ___ 23.17 ___ 24.59 ___ 24.29 ___ 23.17 ___ 24.43 ___ 22.68 __ 1957 _____ 24.00 ___ 22.69 ___ 23.89 ___ 23.20 ___ 24.22 ___ 22.76 ___ 22.85 ___ 22.94 ___ 22.52 ___ 25.18 ___ 23.34 __ 1968 _____ 23.52 ___ 23.94 ___ 24.00 ___ 24.42 ___ 23.09 ___ 24.52 ___ 23.45 ___ 23.09 ___ 23.39 ___ 23.87 ___ 23.28 __ 1979 _____ 23.50 ___ 24.80 ___ 24.35 ___ 22.91 ___ 24.93 ___ 24.05 ___ 23.00 ___ 23.09 ___ 23.89 ___ 24.80 ___ 23.15 __ 1990 _____ 23.74 ___ 24.61 ___ 22.50 ___ 24.94 ___ 24.55 ____ 24.74 ___ 22.83 ___ 22.96 ___ 23.41 ___ 24.83 ___ 22.28 __ 2001 _____ 23.85 ___ 24.43 ___ 23.11 ___ 22.94 ___ 25.04 ____ 23.83 ___ 23.04 ___ 24.11 ___ 22.20 ___ 25.44 ___ 24.41 __ 2012 _____ 24.17 ___ 24.28 ___ 23.54 ___ 24.63 ___ 24.85 ____ 23.48 ___ 24.33 ___ 24.22 ___ 24.93 ___ 24.41 ___ 24.85 __ 2023 _____ ___ avg _____ 23.05 ___ 23.28 ___ 23.01 ___ 23.36 ___ 23.74 ___ 23.32 ___ 23.16 ___ 23.35 ___ 23.30 ___ 23.94 ___ 23.16 ANALYSIS: There is definitely a peak in this cycle as postulated, in year 10. The peak is around 1 F deg or 0.6 C deg above the run of data in the rest of the cycle. A sub-peak almost as warm occurs in year five, so a pulse of 5,6,5,6 years run hotter (in summer). It should be noted that proponents of this cycle have not claimed that it extends back before 1900 and the data show that to be the case, 1878 and 1889 are not particularly warm summers. 1900, 1911, 1944, 1955, 1966, 1977, 1988, 1999 and 2010 are more impressive members than 1922 or 1933 (which is warm but similar to all summers 1931-36). In the last opportunity, 2021 was a bit cooler than 2020 or 2022. The year five sub-peak has occurred in 1873, 1884, 1895, 1906, 1917, 1928, 1939, 1950, 1961, 1972, 1983, 1994, 2005 and 2016. This sub-peak only becomes noticeable after 1983, before that it did not stand out from the rest of the data at all. As to what might be causing this 11-year summer temperature peak, it does approximate the pulse of quiet sun years between sunspot cycles, although more precisely it falls during the rapid increase phase at the early opening stages of sunspot cycles from 1944 onward. That may be its actual cause, but solar irradiance peaks at the peak of sunspot cycles. Perhaps the slightly less radiant heat source at quiet to increasing Sun has the tendency of inducing a trough over central North America which would put NYC into a southwest flow. Your thoughts? It could be postulated that this is nothing more than a statistical fluke, something that will not persist into the future (just as it apparently had little vitality in the cooler 19th century). Future peaks would be expected in 2027 (yr 6) and 2032 (yr 10), then 2038, 2043 etc. We'll have to track this into those future decades, or perhaps you will do that as I am 74 now. Note there is nothing in this data set to suggest an alternative to AGW, the trends are rising for all columns and this appears to be a natural cycle superimposed on the human-induced or possibly partly-otherwise-generated recent increases. I will analyze a longer set of CET data to find out if any 11-year variations are evident there. From a brief inspection I don't think the peaks would be at the same two points in the cycle (if any exist at all). C to F conversions 22.0 C is 71.6 F, 23.0 C is 73.4 F. 24.0 C is 75.2 F, 25.0 C is 77.0 F 22.5 C is 72.5F, 23.5 C is 74.3 F, 24.5 C is 76.1 F, 25.5 C is 77.9 F 0.10 C is 0.18 F in terms of differentials.

Complete list of 3" daily rainfalls in July at NYC, and also 3.00" two-day totals. (the 3.0" list does not include any slightly lower values that might occur using a day on the other side of a heavy rainfall) Notice that many of the entries are towards the end of July. Note the 3.0" daily list continues with a few near-3.0" values to balance the entries. RANK ____ Amount __ Date ______________ 2d amount __ Dates _ 01 ______ 3.75" _____ 23, 1997 ___________ 4.62" _____ 23-24 1997 (3.75" + 0.87") _ 02 ______ 3.56" _____30, 1960*___________ 4.37" _____ 26-27 2000 (3.24" + 1.13") _ 03 ______ 3.47" _____29, 1980* __________t3 4.33" ____ 8-9 2021^ _ 04 ______ 3.24" _____26, 2000 __________ t3 4.33" ____ 5-6 1901 (3.07" + 1.26") _ 05 ______ 3.16" ______13, 1972*__________ 3.64" _______ 29-30 1971 (0.64" +3.00") _ 5.87" 4d total July 29 - Aug 1 _t06 ______ 3.13" ______ 7, 1984 ___________ 6 3.56" _____ 30 1960 (29, 31 dry) _t06 ______ 3.13" _____ 17, 1995 ___________ 7 3.36" _____ 17-18 1995 (3.13" + 0.23") _ 08 ______ 3.11" ______28, 1913 ___________ 3.30" _______ 10-11 2020 (2.54" + 0.76") _ 09 ______ 3.07" ______ 5, 1901 ___________ 3.19" ________ 3-4 1967 (2.08" + 1.11") _ 10 ______ 3.06" _____ 28, 1902*__________ t10 3.14" _____ 6-7 1984 (0.01" + 3.13") _ 11 ______ 3.00" _____ 30, 1971 ___________ t10 3.14" ____ 28-29 1913 (3.11" + 0.03") _t12 ______ 2.91" ______ 17, 1877**_________12 3.12" _______13-14 1897 (2.29" + 0.83") _t12 ______ 2.91" _____ 29, 1872*__________ 13 3.09" ______ 11-12 1937 (0.41" + 2.68") _ 14 ______ 2.80" ______ 3, 1930* _________ 3.06" _________ 28 1902 (27, 29 dry) _ 15 ______ 2.65" _____ 27, 1889** ________ 3.00" _________ 30-31 1918 (2.00" + 1.00") ______________ also including dates in July and August 3.99" 31st-1st 1889 (2.29" + 1.70"), and 3.71" June 30 - July 1 1984 (3.07" + 0.64") _________________ would rank 6 and 7 if included, and expand total list to 17 entries plus next 3 below for top 20. ______________ missing out by 0.01" was 22-23 1946 (2.99" from 0.87" + 2.12") and 20-21 1988 (2.99" from 1.28" + 1.71") also 2.91" 3-4 1978 (1.72"+1.19") ________________________________________ * No measurable rainfall on days before and after these entries, meaning they have the same representation in 3.0" list, or no representation if below 3.0" like 29th, 1872; ** Others have measurable amounts on one or both sides of a heavy amount, only the larger of the two totals is shown for 2d amounts (would have included any nearly equal but there were none). 17th 1877 added only 0.01" so does not make the second list. ^ Total from 2.27" and 2.06" both daily records. (8-9 July 2021)