TheClimateChanger

The Canadian smoke forecast has a large area of PM2.5 exceeding 250 micrograms per cubic meter of air.

Tuesday still looking like there may be poor air quality for much of the Midwest.

Looking at this animation of aerosol optical depth, it looks like some of this might end up getting caught in the circulation of the low pressure system moving through and ultimately advect southwestward over Wisconsin and Ilinois by Tuesday. Obviously a long way out, but perhaps something to watch out for next week. Also, it's not clear how dense the concentrations of smoke will be as a lot of it will get pushed eastward out to sea before the low starts to take shape. https://twitter.com/m_parrington/status/1672232383842492419?s=20

Here was an interesting comparison shared by @BAMWX on Twitter. Worse than 2012, but not quite to 1988 levels.

Where is this massive pall of dense surface smoke expected to travel?

Visible satellite shows the light haze over the Midwest, as well as the suffocating, dense pall of smoke over eastern Canada. Will be interesting to see where this goes. Intense fire behavior is expected over the next couple of afternoons, which will result in additional large emissions of smoke and possible pyrocumulus and pyrocumulonimbus activity. Can also see some of the smoke plumes in western Ontario which are expected to spread smoke into the Upper Midwest later today and into the weekend.

As expected, saw some light smoke and haze in northern Michigan yesterday, which worked its way over to parts Wisconsin and Illinois overnight. Nothing too crazy, but visibilities have been reduced to 4-6 miles, with less than ideal air quality. The HRRR is indicating the potential for a couple more impactful intrusions of Canadian wildfire smoke. Some denser plumes of smoke are expected to work into northern Minnesota and the upper peninsula of Michigan, and perhaps get drawn south around the circulation of an area of low pressure into the Dakotas and possibly parts of Nebraska and Iowa by Sunday. At the same time, a MASSIVE pall of dense surface smoke is forecast to spread across much of Ontario and Quebec. This makes NYC's smokemageddon look weak. Not sure where this smoke pall will travel, but places in the Great Lakes and northeastern US should keep an eye on its path.

Is he trustworthy? I see some of these "agwx" gurus on Twitter, and they can be quite cocky. At least BamWx acknowledged their forecasted pattern change didn't materialize, but DT is like the left-wing Q-anon with rain always two weeks away. He's been going on about widespread rains in the Cornbelt in two weeks seemingly for a month now.

No doubt 1936 was hot in the center of the country, but when you are dealing with fractions of a degree, every location matters. I feel like these old years should have error bars attached to them. It's bizarre how the Weather Bureau sites tend not to show these early years to be as hot as the random co-op sites, which makes no sense since the Weather Bureau was collecting temperatures on rooftops in dense urban areas. I do not believe 1936 is as hot as implied by the ranking. There are numerous biases that are not being adequately corrected in the instrumental record, with many locations showing temperature anomalies that differ considerably from the division/county averages. I understand that these are averages of multiple sites, but these are still concerning discrepancies. While 2021 officially edged out [or statistically tied with] 1936 for hottest summer, it wouldn't surprise if 1936 was actually cooler than 2022, 2021, 2020, 2018, 2016, 2012, 2011, and 2006, all of which were within about 1/2 of a degree. And JB's argument that it was hotter in 1936 on a population-weighted average makes zero sense. The core of the heat that summer was in Montana, the Dakotas, Nebraska, and Iowa, with not as hot to cool anomalies in the more densely populated Great Lakes, as well as the East and West Coasts. Texas, too, wasn't that hot overall. It looks like it would perform very poorly on a population-weighted average compared to recent years where the densely populated Coastal Regions were the ones scorching. One other thing to consider in comparing years is humidity and apparent temperatures. Humidity was exceptionally low during the Summer of 1936, so apparent temperatures during the worst of the heat were likely a few to several degrees cooler than actual temperatures. This has not been the case during recent scorching summers. If it was indeed the hottest summer on record up until 2021, then it was a heck of a way to run the hottest summer on record for many locations in the eastern US, with very cool overnight minima and generally not excessively hot daytime maxima outside of an 8-day stretch in July and a scattering of dates in August. June, in particular, was quite mild, as well as the majority of July, besides the extreme heat wave.

There are so many weird anomalies with 1936. It really wasn't that warm of a summer from Chicago/Milwaukee on east. There was an extreme 8-day heat wave in early to mid July, outside of that it was mostly cooler than modern normals. Especially with respect to overnight minima. As far as minima, it was a summer of yesteryear. In Milwaukee, the mean July maximum temperature of 82.5F is tied with two other years for 27th warmest on record. Yet the southeast Wisconsin divisional ranking shows a mean maximum temperature of 90.2F for the division, or 7.6F warmer than the 1901-2000 average, for third warmest on record. For the summer as a whole in Milwaukee, the mean temperature was 69.9F, or a rather pedestrian 49th of 152 years. For the state, however, NCEI has the summer as 17th warmest on record, as it does for District 9 [SE Wisconsin]. And yes, there was a site change. But the downtown city office was actually WARMER than the current airport location, and so the site change actually results in a warming bias. Looking at Hagerstown, Maryland area for July 1936, we see a mean temperature of 73.8F, nearly 4F below the modern normal. Yet the NCEI county mapping has Washington County, Maryland as 1.4F above normal. Outside of the aforementioned 8-day heat wave, this is legitimate summer of yesteryear stuff for that part of Maryland. And well supported by the observations taken in Baltimore and Washington, DC. (see below). Here is the observations from the Brookville FAA Airport site in Jefferson County, Pennsylvania in July 1936. The mean low temperature was 49.6F, and the mean temperature was 67.7F. These are already summer of yesteryear numbers. Excluding the midmonth heat wave, it was downright frigid that month. Note that these are uncorrected for time of observation bias. By comparison, here are the coldest monthly average low temperatures observed at the current Jefferson County Airport (several hundred feet higher in elevation than the Brookville site): And the coldest mean temperatures: Here's the records from the cooperative observer in New Castle, PA, with comparison to modern mean. And these are uncorrected for time of observation bias, which partially explains why the maximum temperatures are so high: Lows of 36F on July 30th and 31st, at New Cumberland Locks and Dam on the Ohio River in northern West Virginia: Wheeling, WV - July 1936 is 6th lowest mean minimum temperature in station thread history: Morgantown, WV - July 1936 is 4th lowest mean minimum temperature in station thread history: Overall, at Morgantown, it was 72.8F in July 1936, or 1.3F below the modern average. This is 51st coolest [out of 140 years of records]. NCEI has Monongalia County at 72.6F for a countywide average. This makes zero sense. Morgantown is obviously the warmest spot in the county, and this 72.8F reading is uncorrected for time of observations. Most of eastern Monongalia County is 2000' plus ridges - how is the countywide average so high? It also turns a cool anomaly into a warm anomaly, making it 48th warmest [out of 128 years].

What the heck is going on in Iowa? Iowa meteorologist Chris Gloninger steps down after receiving threats - The Washington Post

Iowa meteorologist Chris Gloninger steps down after receiving threats - The Washington Post

Not sure who to believe. The HRRR continues to model a high-end smoke plume over the northlands, but the I can find no mention of smoke in any NWS forecasts. The concentrations being depicted seem capable of changing the color of the sky to shades of yellow, orange or red, completely blocking the sun, reducing visibility to less than one mile, and resulting in very unhealthy to downright hazardous air quality. For the UP of Michigan, this is a long duration of some of the most dense smoke east of the Mississippi I have ever seen on the HRRR, and yet there is no mention of smoke or haze in the forecast.

While there may be a touch of haze and somewhat degraded AQI in Wisconsin and northern Illinois, this looks like a legitimate orange sky, downright hazardous air smokemaggedon for the Arrowhead of Minnesota, and perhaps the UP of Michigan later on. Several large fires in western Ontario not far from the international border with expected explosive fire behavior on Friday afternoon pouring smoke right over the border. I know they don’t issue PDS air quality advisories, but this looks like a particularly dangerous situation. Hazardous travel conditions also possible with poor visibility in dense smoke and haze.

Atrazine... nasty stuff, be careful with it. Potent endocrine disruptor, which has been observed to turn male frogs into females. Source: https://news.berkeley.edu/2010/03/01/frogs/

And for clarification, these were observed at the Federal Building, which was warmer than the current airport location. As you can see from this record for July 1945 below, the airport was found to be 1.9 degrees cooler than the downtown observation site. In 1945, the normal temperatures at the airport for the month of July were a high of 76.3F, a low of 60.0F, and a mean of 68.2F. At the downtown office, the normals were a high of 78.2F, a low of 62.0F, and a mean of 70.1F. So the temperatures in July 1936 at Milwaukee would have been 4.8F above the mean for downtown (or a whopping 6.7F above the mean for the airport site, which didn't yet exist). However, it is only 1.6F warmer than the modern normal for the airport site. When you go back through these old records, it's always incredible to see how much it's warmed. The normal July mean temperature in that era was 5.1F colder than the modern normal mean temperature. The normal high was only 3.0F warmer than the modern normal mean temperature. And the normal temperatures were much closer to modern June normal temperatures than modern July normal temperatures. Note also that these were rooftop measurements, which Watts et al. has shown can be substantially warmer than ground-based measurements. With proper siting and exposure, it may have been even cooler than reported. Source: How not to measure temperature, part 48. NOAA cites errors with Baltimore's Rooftop USHCN Station Heck of a way to run the so-called "Hottest Summer on Record."

1936 was mostly a paper tiger. Other than an 8-day heat wave, it was a very pleasant summer by modern standards. It was only hot in places where nobody lived. Keep in mind, too, that there was only 2.21" of rain at MKE in June & July combined. So you know dewpoints were likely in the 40s and 50s during the heat wave. Might not have even reached heat advisory status, since the apparent temperature would have been lower than the actual temperature. June July *Excepting the 8-day period from 7/7 to 7/14, the mean high and low were 77.0F/63.7F, with a mean monthly temperature of 70.3F. August

I think most people would be thrilled with this outcome. July 1936 was generally summer of yesteryear standards compared to recent years outside of a 7-8 day extreme heat wave. Even including the heat wave, it was generally at or below modern normals in much of the eastern US. Just by way of example, at New York City, the average high was 86.0F and the average low was 66.4F, with a mean temperature of 76.2F, which is 1.3F below the 1991-2020 normal. Excluding just 8 days [7/8-7/15], the average high plummets to 83.1F and the average low drops to 64.5F, producing a very comfortable mean of 73.8F over that 23-day stretch. With modern amenities like A/C, it wouldn't be too difficult to weather a similar stretch. Especially if it meant the rest of the month produced low temperatures not seen in decades.

Looks like there may be a pretty solid plume of smoke, including concentrated surface smoke, on Thursday extending from northern Michigan into the Chicagoland area and southern Wisconsin. Potential exists for degraded air quality.

Not super impressively ranked, and kind of cherrypicked on the date range, but it has been the 10th coldest mean minimum temperature on record for the period from May 1 through yesterday (6/18) at PIT. Obvious data quality concerns, the 1907 reading was from downtown, and the 1945 at AGC, and would likely rank higher if measured at the current observation site. On the flip side, the 1960s are probably overrepresented as the surroundings around the airport were still very rural then and the airport itself less developed.

Here is what the smoke pall looked like from 35,000 feet this morning over Illinois.

Webcams revealing some of the filthy air over the Twin Cities today:

Well, I generated the table in Excel, but the data was sourced from here: CLIMOD 2 (cornell.edu) Select "Seasonal Ranking", and then set variable to "Minimum Temperature" and summary to "Minimum", select the month or other time frame you want to see, and use station ID "MKETHR" [THR for threaded records, if you just use MKE it will only return records from the airport].

This can't be normal, can it? How can it be in the mid and upper 90s on the coast of James Bay and the south end of Hudson Bay, and in the 70s here?

You should be in a pretty good spot, especially in the coming decades. People probably said the same about southern Michigan in the 1860s, as you can see from this table displaying the average monthly coldest minimum temperature by decade at Lansing: how can you plant anything in a spot where the first freeze occurs in August and sometimes in July (like 1863)? Now 160 years later, and it seldom drops much below 50F in those months, and the first freeze doesn't occur until October. The September mean monthly minimum so far this decade is 9F higher than the August mean monthly minimum from the 1860s.