Happy Father's Day - Chris's Corner 19 June 2022

I am sitting at 106* on my remote unit 7 miles west of De Soto. It is usually 2* too warm. Any verifications from around this area?

2012 was wild. I remember we’d be at 100 already by 10am on some of the really hot days.. Then some clouds would come thru and prevent things from going too far above.

98 in Belleville. I have a "beehive"on my outside sensor which is hanging at exactly 2m spice ground from a tree. No solar contamination.

Be mindful of your sensor setup.

Several 104 obs now so it's probably a lock

This could have a lot to do with age/getting old but it sure seems like the 'intensity' of the sun has become stronger than I remember...(which also could have a lot to do with age). Just walking from the house to the outbuilding, when I get in full sunshine it feels like I am being 'microwaved'. I don't 'actually' knows what that feels like but can't think of a better description. I know I have less hair (none) than I used to so I am discounting that and just going by the feeling on bare legs and arms.

104 at 3 PM. Hottest day of the year to this point.

This headline.......

"The World Meteorological Organization has ‘no immediate plans’ to name heatwaves."

102-103 here in Fletcher

We're getting a consecutive string of 106 values now.

According to the ASOS User Guide the data logger samples once every 10 seconds. It then records a 1-min average. There are 1440 of those each day. We don't get to see those. It also reports 1440 5-min averages each day. We only get to see 288 of those on the 5-min METAR website. I'm seeing conflicting information on how the Tmax and Tmin are selected. Some of the literature says they are selected from the set of 1440 1-min averages and some says they are selected from the set of 1440 5-min averages. I'm not sure exactly which it is. I thought I had heard it is was 1-min average. Either way we often miss Tmax on that 5-min METAR website because we're only seeing a subset of the data.

There's a tongue of deeper mixing working up 44 that's allowing temps to reach 105+. And likely some moisture pooling ahead of the OFB across IL keeping dewpoints elevated and temps lower on this side. It's been hovering around 98* in Brighton for a couple hours.

105° is the official high at lambert

Gross

We made it to 99* today...still haven't cracked 100* here. HI topped out at 111*

Ok, I think I figured out how the 5-minute METAR webpage is working.

What I think it is doing is taking the raw F reading and storing it in C to the nearest integer. It then converts C to F when you have "US units" selected. That means there are values of F you'll never see. These values are 107, 105, 103, 101, 98, 96, 94, 92, etc. which are rounded up to 108, 106, 104, 102, 99, 97, 95, 93, etc. So when we see 106 it could be either 105 or 106. However, the hourly summary record does provide the exact F value.

According to the ASOS User Guide the data logger stores 1-minute averages in 1/10 degree C. And according to the following blurb I believe the Tmin and Tmax are selected from the 1440 5-minute averages.

Once each minute, ASOS uses the running 5-minute
average ambient temperature to update the hourly
maximum and minimum ambient temperatures. At the
end of the hour (H+59), the cumulative maximum and
minimum ambient temperatures for the hour and the
minute(s) they occurred are stored in memory for 24
hours.

All of this explains why the official Tmax can be 1 F lower than what you see on the 5-minute records. And the fact that we aren't seeing all of the 5-minute reports explains why the official Tmax an be higher that what you see.