beavis1729

Maybe 1995-96? Chicago had its earliest freeze on record (ORD hit 32F on 9/22/1995)...then the next day was even more impressive with a low of 29F on 9/23/1995. Or, 1993-94? September 1993 was Chicago's coldest September on record, 59.2F vs. the 1981-2010 normal of 64.6F. Could have been lingering effects of Pinatubo?

^ Very impressive for Eau Claire...a 74-year-old record broken by 6 degrees. And it looks like Rockford IL will shatter the record low max for 9/9. Record is 63 set in 1924, but it will probably only hit 59-60 today.

Not saying it’s “fake”, I just don’t like how humans are artificially warming and modifying the environment around us. And it’s not good that the suburbs keep expanding. It’s not natural. Not saying humans should strive for a prehistoric utopia, but there needs to be a balance between long-term planning for the good of the earth vs. the individual freedoms that individuals and companies have to make short-term decisions at the expense of long-term considerations. Communities over individuals.

As much as we're talking about Denver, it has been and will be even crazier in Laramie WY. High of 91F yesterday after it was in the 40s during the AM with haze/smoke from wildfires, then winds gusted out of the NW and it hit 90/3 at an hourly ob, RH 3%. Laramie is around 7,200 feet elevation. Expecting 4-8" of snow Mon-Tues, with a low near 0F on Tuesday night.

The 2-day temp drop at DEN later this weekend could be around 63 degrees, from 91F On Labor Day to the upper 20s at some point on Tuesday. So, probably won’t make the top 10, but very impressive for September, and early in the month at that. It hit 101F today, a new all-time September record high. There have been 10 occurrences of a 66+ degree 2-day temp drop at DEN, but none have occurred in September. They were all Oct-Feb. Largest 2-day temp drop on record is 76 degrees, from 58F on 12/13/2008 to -18F on 12/14/2008.

Earliest first measurable snow: 9/3/1961 (4.2”) Average first measurable snow: 10/18 Warmest temp on the day before a measurable snow: 92F on 9/12/1993

Darker red color right by ORD.

61-day streak of consecutive 100+ days ended today in Las Vegas. 2nd longest streak on record.

Good to know the sensor is fine, but all that other stuff is troubling. People outside of the scientific community probably don’t care...but it’s not good to disturb the site around a sensor over time. Shouldn’t the powers that be have considered this before moving the sensor to its current location? One could argue that this biased temps upward just enough to land the hottest summer on record for Chicago. There will always be an asterisk. A similar thing probably happened when ORD only hit -21 on 1/31/2019, when many other sites in N IL were -25 to -30 or even colder. It just bothers me when science gets compromised like this. The lack of attention to detail is unfortunate.

Ha, I agree and you beat me to it. Consistency of 85+ high temps plus warm (but not record-breaking) overnight lows due to UHI = record warm summer. Never thought Chicago would see a record warm summer with only 3 days of 96+ highs. UHI played a huge role. One would expect overnight lows to be a bit cooler due to the general dry soils in the area throughout JJA, all else being equal. But that didn't happen. Also, only 8 (!) of the 92 days this summer at ORD were below normal. 5 in June, 0 in July, 3 in August. I still think there's something up with ORD's sensor, location, etc...as the temps at ORD this summer seemed to be materially higher than PWK, which isn't very far away (and isn't really much closer to the lake) as the crow flies. At a minimum, it illustrates the scientific "peril" of having wx obs taken at airports. Besides the UHI due to the abundance of concrete at airports, it doesn't help when ORD does construction on runways and has to re-locate the sensor. It tarnishes the historical record. Good stats Chicago Storm.

DFW hit 105 today, with a max HI of 115.

RFD is even drier this August, only 0.52".

Yep, understood. Of course there is no "one size fits all" rule, and it depends on the season and the antecedent conditions on a given day. But, anecdotally, I'd suggest the average UHI impact is a bit greater than what you noted. This morning, RFD (72F) was 2F warmer than "baseline"...namely FEP, a very small nearby rural town that dropped to 70F. Overall, from what I've seen over the years, RFD will check in at 1-2F warmer than nearby rural areas. Probably 2-3F higher at night (especially in winter), and 0.5-2F higher during the day. Just estimates, of course...but significantly greater than 1/3 of a degree F. Another example - the MSP metro area (3.5 million population) has a huge UHI problem...amplified further in the winter when the rural vs. urban differences in radiational cooling become apparent. I've seen many winter mornings were it will be -10F to -15F in areas outside (and even south of) the metro area, but MSP will be much warmer, around 0F. And, sometimes, it can come down to the very microscale detail of the exact location of the ob site. You always hear about the joke of DCA (one of the Washington DC airports), where the thermometer is right on the tarmac and right by the river. DCA also records much lower snowfall totals due to this. Same idea with BDL - Bridgeport CT. I know airports have historically been a convenient place to record wx obs, but it's probably not the most representative when jet exhaust and concrete can be even more intense than a "regular" urban area. Not meaning to argue about this, of course...just a good discussion. Back to the heat wave - looks like ORD hit 94/70/100 today. While I'm on a roll with pet peeves, it's still shocking to me how there have been no heat advisories in the Chicago metro area all week, when we've had 5 (?) consecutive 90+ days...especially noting that it's late August and can be considered "out of season" heat. I would even suggest there should've been heat advisories if this were June/July...but especially for late August. A heat index of 95+ is pretty miserable, especially with full sun, the cumulative effects day after day, and little nighttime relief in the metro/urban core (heck, ORD had a low of 78 this AM...and it was probably similar in Chicago proper with 2.8 million people). But I digress...

I agree that it has been surprising how high the DPs have been around here during this heat wave, even with the very dry ground. That has made it challenging to predict the high temps each day. The dew never dropped below 61, and was 65-70 most of the time. Maybe it's because the air is advecting over wetter ground/corn fields...or that late August is generally a climatologically humid time of year, especially if the air isn't coming directly out of Canada?

Ties the daily record high min, set in 2018 (!). Also, there has never been a min of 79+ after today's date. Normal low at ORD is 61, although that's also been a joke the past 5-10 summers, as ORD seems to have above-average mins in summer on 75%+ of days. It's like grade inflation; "every day is above average". I know it's beating a dead horse, but the UHI at ORD is crazy and just keeps getting worse. RFD, not exactly a rural paradise, had a low of 72 this morning. Same air mass, yet 6 degrees cooler than ORD. FEP hit 70. There was no easterly component to the wind, so the warm lake had nothing to do with it. UHIs are so unfortunate anywhere they occur, as it's indisputable evidence that humans are messing with nature.

Agree...and the Midwest does too, of course mostly driven by latitude instead of distance to the coast...although there's some relative temperature moderation immediately downwind of the Great Lakes. As an example...STL hardly has winter, I-80 in Illinois is very limited winter, Chicago is in between (where you can run a good 2-3 week stretch of winter sometimes, with crap for the other 9 weeks), Madison WI is decent, then central WI northward is much more consistent winter. The gradient between 40N and 44N in the Midwest is pretty staggering in a typical winter; not too many miles as the crow flies. If you drew a contour map of Average Annual Snow Depth Days (SDDs) in the Midwest, you'd see a crazy gradient by latitude. Normal high temps in January range from around 40F at 40N, to 22F at 44N. Apologies if this is going a bit off-topic. Nice to be in this sub-forum with the banter and good discussion about winter...keep it up.

There's some haze/smoke in the area from nearby wildfires. So, looks like it may only (!) hit 127-128. At 2 PM local time, it's 125/47, heat index 118.

Brian D, keep us posted with obs this fall and winter, it’s great to have a new poster from the far north.

Interesting...the greater than normal disparity between ORD and MKE this season is probably because most of ORD’s 90+ days have been 90-92, combined with UHI. Where I am in SW Lake County IL, we’ve only had 12 days of 90+. A lot of days 87-89.

A bit dry in Las Vegas...it's currently 105/8, RH 3%.

Just brutal conditions in Phoenix the past few days. This is the time of year where the peak heat of summer is still lingering, with the monsoon moisture in play too. Yesterday it was 116/52 at 4pm. That’s a pretty high dew point, given the temperature. At 1am this morning, it was 101/63, and the low temp this morning was 93. Combined with the urban jungle landscape...yuck, yuck, and more yuck.

Hard to believe there is no heat advisory in the LOT CWA. I know there are certain criteria that technically need to be met, but it’s brutal out there. If no heat advisory on a day like today, I can’t imagine many other days that would warrant it. Maybe the criteria needs to be reviewed. Maybe I am less tolerant of the heat than others, but a HI of 100 should warrant an advisory, especially with warm overnight mins. I would even say a HI of 95 should suffice, but that’s just me.

Langdon ND (near the Canadian border) is currently 86/81/102. Has the dewpoint ever hit 81 this far north in the US before?

Yeah, that May 1977 warm spell was impressive. 1976-77 was an interesting time. Besides being in the early stages of disco fever , the winter was extremely cold here, followed by a record warm spring...and a snowstorm in New England on May 9-10.