Days Per Year of 90°> Where You Live

[Phil]

Another 90*F+ afternoon, more humidity today too.

 

Urban areas will fail to drop below 70*F for several days. Hate this pattern with all that I am.

[Anti Marine Layer]

90 F here today with dewpoints in the upper 20s.

[Phil]

Today sucked..91*F with a dewpoint of 70*F. Sounds like summer outside with the chorus of katydids and crickets.

[Phil]

Only good thing was the humidity helped the baseballs carry today. Hit a few 400ft+ shots out to center field during batting practice. ️

[wx_statman]

91 & 92 at Burlington, VT the last two days. They had never seen 90 after Sep. 16th previously. In fact they had never been above 85 this late in the season before. 

[Phil]

[Phil]

Hopefully this is the last time I'll have to stare at fogged up windows until next year. Our first continental front of the year will blow through tonight.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/74C0CF01-615D-4B99-8D89-7A97B4F053A4_zpsdtz7umxu.jpg

[Phil]

Maybe now we're done with 90*F+ days. Feels more like early autumn now, after a few nights in the upper 30s/low 40s across the region.

[Phil]

[Guest happ]

This is a nasty dewpoint for October, even by swamp standards.

 

 

 

http://www.wrh.noaa.gov/zoa/getobext.php?sid=KDCA

 

Dewpoint temp of 83° is beyond miserable.    I don't think it has ever been that humid here.

[Phil]

[Phil]

[Guest happ]

Looks like it's "only" 75*F , thankfully. If it was 83*F, I'd have committed suicide already.

 

Looks like it's "only" 75*F , thankfully. If it was 83*F, I'd have committed suicide already.

 

Oops, I mixed up air temp w/ dew point. Do dew points get up into the 80's in DC?

[Phil]

Oops, I mixed up air temp w/ dew point. Do dew points get up into the 80's in DC?

Pretty much every summer, yeah. I've seen up to 87*F (July 2011 after a midday downpour was evaporated by sunshine).

 

Heck, it's 83/76 right now, in the middle of October. This would be a 104/86 afternoon in late July, lol.

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/7F614060-46B0-4DA0-B6BD-6EEC65B4DA8C_zpsbvpjist4.jpg

[Guest happ]

I guess things used to be worse. The October dewpoint record for DCA is 78*F, set back in the 1950s. Yuck.

 

Back in the 1940s, which featured the most humid summers on record, the dewpoint reached 90*F ( ) on June 13th of 1943, following a midday downpour, and reached 88*F-89*F three other times.

 

By comparison, the highest dewpoint observed in the 21st century is only 82*F, and in the satellite era, the highest dewpoint recorded was only 84*F, back in the 1980s. So I guess at some point we'll see 90*F dewpoints again, and this mid-70s stuff will be a cakewalk by comparison.

 

Those readings must reflect extremely high SST

[Phil]

Those readings must reflect extremely high SST

Yeah, or at the very least, some toasty Chesapeake/Potomac temperatures. Not that uncommon for those waters to reach the mid/upper 90s. Warm Gulf/SW-Atlantic SSTs, as you just mentioned, are indeed our primary moisture pump, so my guess is those waters were also very warm.

 

The 1930s/1940s were warm across the globe, actually. I think that warm period might be underestimated by the surface temperature datasets, at least to some extent, as many of the best-measured domains (North America, Arctic, Europe, etc) set a slew of temperature records, many of which still stand today.

[wx_statman]

Yeah, or at the very least, some toasty Chesapeake/Potomac temperatures. Not that uncommon for those waters to reach the mid/upper 90s. Warm Gulf/SW-Atlantic SSTs, as you just mentioned, are indeed our primary moisture pump, so my guess is those waters were also very warm.

 

The 1930s/1940s were warm across the globe, actually. I think that warm period might be underestimated by the surface temperature datasets, at least to some extent, as many of the best-measured domains (North America, Arctic, Europe, etc) set a slew of temperature records, many of which still stand today.

 

It's too bad that so many long station records are confounded by UHI, relocation from city centers to airports, relocation to different microclimates, relocation to different elevations, accuracy of thermometers, changes in sheltering, changes in station placement, new development around existing stations (i.e. new airport runways), etc etc. Makes your head spin. I don't blame some people for sticking to satellite data, but even satellite sensors are prone to mis-calibration over time.

 

Spokane is a good example regionally of a station relocation making the 1920s-1940s seem anomalously warm compared to today. Prior to opening of Spokane Int'l (GEG) in 1946, the station was located in the city of Spokane itself at an elevation of 1,879 feet. Since 1946 the official GEG station has been recording at 2,372 feet. That's 500 feet of elevation difference, and it's a fact that's completely hidden to everyone unless they do the research on their own. The NWS simply threads the data together into a continuous POR extending back to 1881 with no obvious mention of the titanic elevation change in the 1940's. 

 

As a result, you get this:

 

62.9 in 1934

61.6 in 2015

61.2 in 1925

61.1 in 1939

60.9 in 1941

60.8 in 1940

60.8 in 1938

60.7 in 1926

60.6 in 1885

60.5 in 1998

 

These are the highest annual average maximums at Spokane. Makes the 1920s-1940s look like they completely dominate the POR for warmth, with recent warming struggling to keep up. One can easily draw a (likely) incorrect conclusion that the climate of eastern WA reached peak warmth in the 1934-1941 period, when it was simply the last warm period before the elevation change. This also puts the historic magnitude of 2015's warmth into proper perspective considering the elevation, something one can't do just by eyeballing the records with no background knowledge.

 

That era was legitimately warm with plenty of legitimate warm records set, I'm well aware of that from my years of trawling weather records. I just wish we had a more accurate way of comparing that era with the present day!

[Front Ranger]

Agreed, wish there was a more accurate way to compare global temps then to today.

 

However, just on a local level, there are some stations that have remained relatively unchanged since the 1920s, and have decent to pretty good records (though all have some missing data, of course).

 

One of those is Landsburg, WA. Its warmest years (of those with probably adequate data) rank:

 

2015

1940

1934

2016

 

At another one, Palmer (the one Tim likes to reference since it's not far from his area):

 

2015

2016

1941

1940

 

At Centralia:

 

1998

1934

1958

1992

1940

 

At Battle Ground:

 

1958

2015

2016

1941

 

Corvallis:

 

1940

1934

2015

1941

 

Cottage Grove:

 

1992

1934

1995

1958

2015

 

Forest Grove:

 

2015

1958

1995

2004

1934

 

Number of times each year was in the top 4-5.

 

2015: 6

1934: 5

1940: 4

1958: 4

2016: 3

1941: 3

 

While admittedly this isn't exhaustively scientific, we can probably safely assume that the 6 years above were all among the warmest of the past 100+ years in the PNW lowlands, and there's a good chance the top 2 warmest were 2015 and 1934. With about equal representation from the 1930-40s as recent years.

[Phil]

Very interesting information, thank you. Yeah, always difficult to adequately homogenize for station relocation.

 

Of course, in the global scheme of things, I would expect the effect(s) of station relocation to even out in the global averages. The disproportionate ratio of extreme warmth to the proposed average temperature (globally speaking) during the 1930s and 1940s is concerning, IMO, because it's solely an artifact of adjustments to the data, apparently due to spatial homogenization and new interpolation procedures. The upward adjustments to global temperatures between 1850-1900, in conjunction with the downward adjustments to the 1910-1960 temperatures, created a much flatter trend-line, during a period dominated by rapid glacier retreat and episodes of extreme warmth around the world.

 

I'm almost tempted to take the original versions of the surface datasets (from back in the 1980s) as more representative of reality than the newer updates.

[Phil]

An oversimplified microcosm of the issue here. Anomalous summer warmth was observed across the US during the 1930s and 1940s.

 

 

Adjustments to the US average temperature are significantly downwards for this period (by up to 2C), then almost exponentially upwards after year 2000. in the modern era, the adjustments average out to positive by 0.7C.

 

Is it a coincidence that these adjustments almost perfectly emulate the trend in CO^2 concentrations?

 

[wx_statman]

Agreed, wish there was a more accurate way to compare global temps then to today.

 

However, just on a local level, there are some stations that have remained relatively unchanged since the 1920s, and have decent to pretty good records (though all have some missing data, of course).

 

One of those is Landsburg, WA. Its warmest years (of those with probably adequate data) rank:

 

2015

1940

1934

2016

 

At another one, Palmer (the one Tim likes to reference since it's not far from his area):

 

2015

2016

1941

1940

 

At Centralia:

 

1998

1934

1958

1992

1940

 

At Battle Ground:

 

1958

2015

2016

1941

 

Corvallis:

 

1940

1934

2015

1941

 

Cottage Grove:

 

1992

1934

1995

1958

2015

 

Forest Grove:

 

2015

1958

1995

2004

1934

 

Number of times each year was in the top 4-5.

 

2015: 6

1934: 5

1940: 4

1958: 4

2016: 3

1941: 3

 

While admittedly this isn't exhaustively scientific, we can probably safely assume that the 6 years above were all among the warmest of the past 100+ years in the PNW lowlands, and there's a good chance the top 2 warmest were 2015 and 1934. With about equal representation from the 1930-40s as recent years.

 

That sounds about right. If I had to pick two years based on everything I know about the regional climate, I'd probably zero in on 1934 and 2015.

[wx_statman]

Very interesting information, thank you. Yeah, always difficult to adequately homogenize for station relocation.

 

Of course, in the global scheme of things, I would expect the effect(s) of station relocation to even out in the global averages. The disproportionate ratio of extreme warmth to the proposed average temperature (globally speaking) during the 1930s and 1940s is concerning, IMO, because it's solely an artifact of adjustments to the data, apparently due to spatial homogenization and new interpolation procedures. The upward adjustments to global temperatures between 1850-1900, in conjunction with the downward adjustments to the 1910-1960 temperatures, created a much flatter trend-line, during a period dominated by rapid glacier retreat and episodes of extreme warmth around the world.

 

I'm almost tempted to take the original versions of the surface datasets (from back in the 1980s) as more representative of reality than the newer updates.

 

The fact that so many of the great heat waves around the world from the 1920s-1940s have never been exceeded is a bit of a head scratcher. And this also goes for areas outside of the Dust Bowl zone, where the heat was obviously aided by widespread dessication of the landscape. One possible theory is that with increasing global temps we've seen an increase in atmospheric moisture, which would tend to limit the extreme peaks. Under this theory, the means and the minimums would go up (both tough to test objectively due to the confounding effects of UHI), while average maximums would also go up. The extreme maximums would either flatline or even decrease.

[wx_statman]

An oversimplified microcosm of the issue here. Anomalous summer warmth was observed across the US during the 1930s and 1940s.

 

 

Adjustments to the US average temperature are significantly downwards for this period (by up to 2C), then almost exponentially upwards after year 2000. in the modern era, the adjustments average out to positive by 0.7C.

 

Is it a coincidence that these adjustments almost perfectly emulate the trend in CO^2 concentrations?

 

 

Leaving the conspiracy stuff aside, that graph shows the droughts pretty neatly. The 1930's and 1950's heat waves were of course aided by the massive droughts in the Plains. Good luck replicating those maximums today especially in the corn belt. Iowa will never sniff 1930's records again with all that corn they're growing and higher Dp's from that.

[Phil]

Leaving the conspiracy stuff aside, that graph shows the droughts pretty neatly. The 1930's and 1950's heat waves were of course aided by the massive droughts in the Plains. Good luck replicating those maximums today especially in the corn belt. Iowa will never sniff 1930's records again with all that corn they're growing and higher Dp's from that.

FWIW, I'm not one to believe in widespread data fabrication or anything like that, however, the fact these adjustments (to the US-based datasets in particular) have always skewed in one direction defies both logic, and more importantly it defies the previously published uncertainty estimates of these datasets. In the case of the US-based surface temperature datasets, I think the problem is that their management has been placed in the hands of an astonishingly small group of people, most of whom have a long history of alarmism and/or political advocacy.

 

I'd like to open the management of these datasets to a much larger group of scientists, for additional scrutiny.

[Phil]

The fact that so many of the great heat waves around the world from the 1920s-1940s have never been exceeded is a bit of a head scratcher. And this also goes for areas outside of the Dust Bowl zone, where the heat was obviously aided by widespread dessication of the landscape. One possible theory is that with increasing global temps we've seen an increase in atmospheric moisture, which would tend to limit the extreme peaks. Under this theory, the means and the minimums would go up (both tough to test objectively due to the confounding effects of UHI), while average maximums would also go up. The extreme maximums would either flatline or even decrease.

That could be, except we'd expect to see this occur whenever the planet warms. The thermodynamic relationship between relative humidity and air temperature has been well understood for awhile now, so I don't see why the current warm period would be unique in this regard.

 

Given the statistical divergence is mostly isolated to the 1930s and 1940s, and given the observed rate of glacier retreat during that era, my hunch is that global temperatures are somewhat underestimated from the 1920s through the 1940s.

[wx_statman]

FWIW, I'm not one to believe in widespread data fabrication or anything like that, however, the fact these adjustments (to the US-based datasets in particular) have always skewed in one direction defies both logic, and more importantly it defies the previously published uncertainty estimates of these datasets. In the case of the US-based surface temperature datasets, I think the problem is that their management has been placed in the hands of an astonishingly small group of people, most of whom have a long history of alarmism and/or political advocacy.

 

I'd like to open the management of these datasets to a much larger group of scientists, for additional scrutiny.

 

I don't know enough about that to comment, so I won't.

[wx_statman]

That could be, except we'd expect to see this occur whenever the planet warms. The thermodynamic relationship between relative humidity and air temperature has been well understood for awhile now, so I don't see why the current warm period would be unique in this regard.

 

Given the statistical divergence is mostly isolated to the 1930s and 1940s, and given the observed rate of glacier retreat during that era, my hunch is that global temperatures are somewhat underestimated from the 1920s through the 1940s.

 

You could be right. I don't know.

 

The glacier retreat was pretty phenomenal here in Oregon during that era. Collier Glacier in the Three Sisters area retreated something like 0.5 km between 1934-1944. That was obviously aided by drought, but still.

[Phil]

[wx_statman]

Wow, that's fascinating. I actually haven't researched the western North American glaciers as much as I probably should have at this point in time.

 

FWIW, the published research on the Iclandic glaciers and winter sea ice suggests a similar tendency there was well. Up until the 1830s, Iceland was typically surrounded by sea ice for at least two months out of the year (occasionally up to 4 months) according to the majority of aggregated mariner reports and records from that era. By the 1920s, the ice was rarely, if ever seen there (at any time of the year), and glaciers had retreated by almost 20-30% from their 1830s levels. The fact this was well after the depth of the LIA makes me wonder how expansive the ice was during the 1650-1700 era.

 

I've read before that Iceland was completely surrounded by sea ice during some of the 1690's winters, to the extend that shipping was impossible to/from any part of the island. I wish there was a way to instrumentally quantify just how much Iceland's climate has warmed over the last couple centuries. It's probably a shocking number since the lack of sea ice has added a compounded warming effect. Just looking at some of the record lows tells the story. Reykjavik hit -12F in January 1918, but has not seen any 0F readings since January 1971. Akureyri on the north coast supposedly hit -35c in March 1810 (according to Maximiliano Herrera), while the modern (post-1949) station has never fallen below -23c:

 

http://meteo-climat-bzh.dyndns.org/mete8-431-1944-2016.php

 

Even today, the northeastern coast of Iceland clings to a tundra (Koppen ET) climate zone (i.e. at Raufarhofn)...I imagine the ET zone covered much more of Iceland in those days.

[Phil]

[Phil]

Some western stations.

 

Salt Lake City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/CD7A06A9-E6BF-4398-AF6A-0915A375CF1F_zpsqbehkeju.png

 

 

Vancouver:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/F07B8179-1115-41D0-A29A-2931635A6B45_zpsla09eraz.png

 

 

Denver:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/A51F7606-915D-4E4F-8F9A-2F82C023BBB3_zpsusfjrezk.png

 

 

San Francisco:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/C208A37E-051C-47B2-9E5A-62871646268E_zpsysg327d4.png

 

 

Some eastern stations:

 

Boston:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/2909BDBD-4369-4C9E-97C8-3E928D0D9F63_zpsei3btf3d.png

 

 

Toronto:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/74B0E2DD-D6CC-4BDF-AAE8-777AC79764E3_zpsp3vl9scf.png

 

New York City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/A534AA6E-2FF0-4FBF-A7E3-28A9940D65DE_zpsvcjkpum5.png

 

 

Da Swamp:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/AB802CA6-4883-436C-AAE4-65DC1E8901A9_zpsfkwpoj5d.png

 

Atlantic City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/44FCB33C-0A63-40CF-A0C6-3B8FA7481D8E_zpsclsglljx.png

[Phil]

Looks like 2014, which was a chilly year in the eastern US by moden standards, would have been a toaster bath by LIA standards. Lol.

[wx_statman]

Some western stations.

 

Salt Lake City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/CD7A06A9-E6BF-4398-AF6A-0915A375CF1F_zpsqbehkeju.png

 

 

Vancouver:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/F07B8179-1115-41D0-A29A-2931635A6B45_zpsla09eraz.png

 

 

Denver:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/A51F7606-915D-4E4F-8F9A-2F82C023BBB3_zpsusfjrezk.png

 

 

San Francisco:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/C208A37E-051C-47B2-9E5A-62871646268E_zpsysg327d4.png

 

 

Some eastern stations:

 

Boston:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/2909BDBD-4369-4C9E-97C8-3E928D0D9F63_zpsei3btf3d.png

 

 

Toronto:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/74B0E2DD-D6CC-4BDF-AAE8-777AC79764E3_zpsp3vl9scf.png

 

New York City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/A534AA6E-2FF0-4FBF-A7E3-28A9940D65DE_zpsvcjkpum5.png

 

 

Da Swamp:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/AB802CA6-4883-436C-AAE4-65DC1E8901A9_zpsfkwpoj5d.png

 

Atlantic City:

 

http://i724.photobucket.com/albums/ww243/phillywillie/Mobile%20Uploads/44FCB33C-0A63-40CF-A0C6-3B8FA7481D8E_zpsclsglljx.png

 

The graphs no longer display for some reason. I could see them yesterday.

[wx_statman]

That could be, except we'd expect to see this occur whenever the planet warms. The thermodynamic relationship between relative humidity and air temperature has been well understood for awhile now, so I don't see why the current warm period would be unique in this regard.

 

Given the statistical divergence is mostly isolated to the 1930s and 1940s, and given the observed rate of glacier retreat during that era, my hunch is that global temperatures are somewhat underestimated from the 1920s through the 1940s.

 

On the flip side, that era also had tremendous cold waves. More impressive than today. So if you were to look at the winter cold waves, you might make the opposite conclusion - that global temperatures were cooler than today and that nothing is wrong with the data. The extremes cut both ways during the 1920s-1940s.

 

I'm specifically referring to winter 1933-34 in the east, winter 1936-37 in the west, February 1936 in the plains, Jan-Feb 1943 nationwide, Jan-Feb 1947 in Alaska/NW Canada, January's of 1940 and 1942 in Europe, etc. IMO those winter episodes trump just about anything we've seen in recent decades in absolute, mid-winter terms. 

[Phil]

The graphs no longer display for some reason. I could see them yesterday.

Ugh, stupid Photobucket. I log out of my account for 10mins and poof, they're gone.

 

I'll re-post them when I finish this math.

[Phil]

On the flip side, that era also had tremendous cold waves. More impressive than today. So if you were to look at the winter cold waves, you might make the opposite conclusion - that global temperatures were cooler than today and that nothing is wrong with the data. The extremes cut both ways during the 1920s-1940s.

 

I'm specifically referring to winter 1933-34 in the east, winter 1936-37 in the west, February 1936 in the plains, Jan-Feb 1943 nationwide, Jan-Feb 1947 in Alaska/NW Canada, January's of 1940 and 1942 in Europe, etc. IMO those winter episodes trump just about anything we've seen in recent decades in absolute, mid-winter terms.

Oh, definitely, but do you think the 1930s/40s were more prolific cold wave producers than the 1850s-1910s? Or do you think maybe anomalous circulations tend to occur more frequently during the cold season?

 

Because, there were some legitimately frigid periods in recent years too, like 1985 in the United States (or even Feb 2015), as well as 2008/2012 in Europe/Eurasia, etc, all of which dropped a bunch of records, many of them set long ago.

[wx_statman]

Oh, definitely, but do you think the 1930s/40s were more prolific cold wave producers than the 1850s-1910s? Or do you think maybe anomalous circulations tend to occur more frequently during the cold season?

 

Because, there were some legitimately frigid periods in recent years too, like 1985 in the United States (or even Feb 2015), as well as 2008/2012 in Europe/Eurasia, etc, all of which dropped a bunch of records, many of them set long ago.

 

That's a tough question. Probably not as prolific as 1850-1890, but just as prolific as anything since then. Feb 1936 for instance is the single greatest monthly cold anomaly anywhere in the US post-1895 when considering the anomalies it produced in MT and the Dakotas (March 1843 probably topped it though in the Midwest). Specifically, North Dakota's monthly average of -13.1F in Feb 1936 is the single coldest monthly average for any state in the lower 48, for any month since 1895. January 1937 is neck-and-neck with January 1949 for coldest month in the western US since at least the late 19th century. The cold waves of Dec 1933 and Feb 1934 can hold their own against any cold wave in the NE in the last 150 years, including events such as Dec 1917 and Feb 1943. You really have to go back to Jan 1857 & Jan 1859 (and Jan 1835 + Dec 1835 before that) before you find legitimately more impressive cold waves than that. January 1940 set numerous city & national all-time record lows in Europe that still stand today, and this includes POR's that extend back to the late 19th century. Same goes for February 1929 in Europe.

 

It would be virtually impossible to rank the magnitude of 1920s-1940s cold waves vs. the late 19th century.

[BLI snowman]

January 1930 was pretty remarkable in the West, too. As was January 1940 in the Southeast (-11F anomaly for that month regionally).

[wx_statman]

January 1930 was pretty remarkable in the West, too. As was January 1940 in the Southeast (-11F anomaly for that month regionally).

 

Yup. I cold have thrown a few more example in there...Dec 1932/Feb 1933 in the west, Jan 1935, Jan 1934 in AK, etc.

[BLI snowman]

Yup. I cold have thrown a few more example in there...Dec 1932/Feb 1933 in the west, Jan 1935, Jan 1934 in AK, etc.

 

Yeah, December 1933 was amazing in AK as well.