We tied or broke virtually every temperature record related to "heat" that you can imagine during the month of July in Salt Lake City. Buckle up. Here we go.
The average temperature for the month was 87.3˚F, 1.6˚F higher than the previous record set just last year and 6.1˚F higher than the highest mean July temperature observed in the 20th century (81.2˚F in 1960). This is also the hottest month ever in Salt Lake City. There's never been anything hotter.
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| http://xmacis.rcc-acis.org/ |
The average maximum temperature was 99.7˚F, which beats the prior record set last year by 1.3˚F. If you want the psych point, you can round that up and say we had an average high temperature of 100˚F for the month.
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| http://xmacis.rcc-acis.org/ |
The average minimum temperature was an incredible 74.9˚F. This is 1.8˚F higher than the prior record set just last year and obliterates everything from the 20th century. The 20th century record was 68.5˚F in 1919 when the National Weather Service observing site was located in what is now downtown Salt Lake City (you can see when the site was moved to the "cooler" nighttime airport location in the mid 1920s as there is a clear drop in minimum temperatures that occur at that time).
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| http://xmacis.rcc-acis.org/ |
Shall I go on? 18 days of 100˚F or more, which is a new record. Maximum temperature of 107˚F on July 17, tying the all-time high reached previously on 26 July 1960, 13 July 2002, and 15 June 2021. Minimum temperature of 81˚F on July 3, tied for 2nd all-time with 18 July 2016 and just behind the record set 13 July 2021. Highest minimum temperature for the month (68˚F) on record. I'm not sure where we stand on the number of days with a minimum of 70˚F or more, but it was surely near the record if not the record.
What records didn't we set? Anything related to low minimum or low maximum temperatures.
Is there any good news? Not really, but the HRRR is forecasting some showers and thunderstorms for this afternoon and evening, as well as a few overnight for northern Utah, so keep your fingers crossed we at least get some precipitation action. My house largely missed out on precipitation during July and my gardens are not happy.
Thank you for detailing yet another hot summer. I'd like to know how many days over 90, as that temp can stifle a lot of outdoor activities! As to windsurfing Deer Creek/Jordanelle both have less thermal wind, the normal "75-80' is now so hot the wind refuses to show. Outdoor tennis after 3pm in SLC is incredibly hot. Even mountain biking up high at Park City is different when all you want is shade.
ReplyDeleteI would love to see a detailed post on the location moves & changes of the official SLC observation site. You mention a move from downtown to the airport in the mid 20's, then there is the move to a different airport location around 2011. The current airport location has undergone significant changes in ground cover since it was installed. In 2011 it was a grassy area with less pavement/buildings around, the observation site now looks to be surrounded by dirt/gravel with more buildings/pavement encroaching the site. Theses factors obviously increase temperatures.
ReplyDeleteI aspects of this quite a while back: https://wasatchweatherweenies.blogspot.com/2013/08/whats-up-kslc.html
Deleteand I have mentioned it in recent posts.
There is no representative observing site in an urban area. Trends are a function of climate change, urban effects, and local land-surface conditions.
It's true that any 1 site is problematic for separating causes for temperature trends, but there are statistical methods designed to address this. For example, see adjustments used in the USHCN network: https://cdiac.ess-dive.lbl.gov/epubs/ndp/ushcn/monthly_doc.html#urbanization, though admittedly, mins and maxes are trickier than averages. And the USCRN was specifically designed to avoid urban areas to act as a reference comparison.
DeleteThanks for adding that Adam.
DeleteI fully agree that trends are a function of climate change, urban effects, and local land-surface conditions. I also can't help but wonder if any of it is slightly amplified by the dying lake? That we don't have the lake to cool us down like we used to. You think there may be anything to this?
ReplyDeleteIf the lake is warmer in the winter and leads to lake effect snow and less lake equals less lake effect... wouldn't less lake mean less cooling in the summer?
Possibly. It's not straightforward to tease out all of these effects at one observing site.
DeleteThanks for your response!
DeleteThis sucks. If memory serves correctly, summer nights generally felt nice and cool when I moved here 4 years ago. I don’t understand how average temperatures can increase this rapidly. This seems to outpace even the disaster scenarios I’ve read about. Surely this rate of increase can’t continue…. Right ???
ReplyDeleteThere will be ups and downs from year to year, but the long term trend is up.
Delete30 days with minimum greater than or equal to 70 this July, the 11th had a minimum of 68. Previous record was 2013 with 26 days.
ReplyDelete1958 was the last year with ZERO mins 70 or above. 1995 was the last year with 1 min 70 plus, 2010 was the last year with 5 min 70 plus.
This year we had 20 days with the min 75 or greater, which goes a long way to explaining why we feel so oppressed. Previous record was 13 days in 2017. 2009 was the last year with ZERO mins 75 plus.
Btw, been meaning to tell you your summer blogging is better than your winter blogging. Probably the heat thing. Also, monsoon meteorology is objectively more interesting than winter storms, though snow is our greatest source of happiness.
Have a bunch of questions on the Great Salt Lake (which is also objectively more interesting than mountain weather) that I if I can organize my thinking will ask you.
Any thing you have to say on our current monsoon would be a delight.
Long winded thank you for your summer blogging keep up the good work.
The SLC airport might as well be Las Vegas at this point. This summer has not felt as bad as all these records would make it seem.
ReplyDeleteThis isn't as easy as you'd think. A quick glance at sites in Salt Lake available via xmacis2 reveals none of them have data for recent years, particulary 2022. Triad, east bench, etc have no recent data.
DeleteOgden Hinkley has basically complete data since 1998. 18 days with min 70 or above in 2022, 20 days in 2021.
After sleeping on it with a reasonably cool last night, have been thinking the landscaping at the airport site is probably skewing recent years hotter.
Jim your point is the airport USED TO BE cooler when the site was switched from downtown in the 1920s. Other things equal, it should still be cooler and it is hot as hell.
From my own perspective, the south winds this year caused a lot of warm nights and the nights in particular this year seemed the warmest I can remember. Also seemed like we had an unrelenting month of hot days.
Would be nice to get a sense how much the landscaping (natural dry grass vs. bare ground, or god forbid landscaping rocks) skews measurements hotter
It doesn't really matter where the NWS site is. We would be arguing about these sorts of issues anywhere in the valley. If it was at the Salt Lake Regional Airport, we'd be wondering what all the development around it was doing or how the decay of the old runways are affecting the local conditions.
DeleteThere is virtually nowhere that hasn't changed.
Peter is also correct that comparisons with other sites are very difficult to make. The NWS Cooperative Network is a volunteer network. Sites come and go. Characteristics at those sites change as well. Quality varies. The NWS observations cover a long period and are nearly complete.
The reality is that this was the hottest July on record as recorded by the NWS. I am comfortable with that statement. If we wish to argue why, then the problem becomes more complex, although we have a pretty good idea that climate change and land-surface changes are both contributing in the positive.
Any insight on the meteorology of why the nights were so warm in Salt Lake if not Ogden this July.
DeleteAs I say, this seemed to be warmest sleeping I can remember in 30 years at my current house and 60 years in the valley.
Did more hotter south wind have an effect or did I make that up. And maybe now that I'm old my memory is bad and nights this July weren't significantly warmer than the last decade.
None. I haven't been watching Ogden. Certainly wind contributed at KSLC earlier in July. Not sure about later.
DeleteThe temps at my house to the southeast of downtown do seem to always be a few degrees cooler than at the airport, and many nights that are sub 70 degrees here are 70+ at the airport, but the nights definitely feel warmer.
ReplyDelete