The main purpose of this ongoing blog will be to track planetary extreme, or record temperatures related to climate change. Any reports I see of ETs will be listed below the main topic of the day. I’ll refer to extreme or record temperatures as ETs (not extraterrestrials).😉
Main Topic: U.S. Average Temperature Summer Forecast
Dear Diary. Today is the first day of boreal or meteorological summer, so once again as we do on this blog, it is time to make a forecast for this coming season. May has been quite odd with the most anomalously warm conditions occurring across the northern tier of states. Will that trend continue through the summer? Will we see major life-threatening heat waves as have already been occurring across Asia across the United States?
At the very start of summer, it’s time for me to make another attempt at a forecast for average seasonal temperatures in the U.S. This forecast will be very broad and not specific for any one state comprising the continental United States (or lower 48 states).
So how did the forecast work out for Spring 2023? Here is a link to the post for that forecast:
By June 8th the National Center for Environmental Information will finish their climatological assessment for Spring 2023, so our verification is not complete as of June 1st. Let’s do fill in ranking numbers with 1 being the coldest and 129 warmest for a verification for months during 2023 (129 will be warmest for 2023.), which have already been assessed:
Here are my two cents for a broad, rough forecast for the U.S. for Summer 2023, which I guarantee to be warmer than this past spring, of course, as the amount of daylight increases across the Northern Hemisphere. First, I like to look at water temperature anomalies surrounding North America just before the start of a season to get a sense of how much potential anomalous heat can be added to the atmosphere across the continent. Here is what we see:
There have been big changes across the Western Hemisphere since winter ended. Water temperature anomalies have cooled some around North America except in the Gulf of Mexico. Obviously, the biggest change has occurred across the Pacific where a strong El Niño is developing. Here’s the thing. As global atmospheric temperatures were responding to the advent of the last two strong El Niño’s in the past, across the United States we saw fairly chilly conditions. Here is my write up on that:
These trends lead me to think that this summer will be the coolest in quite some time. That’s not to write that there will not be any heat waves across the United States during Summer 2023, just that these may be short lived and not as severe as those in the past decade. After the El Niño kicks into high gear after a few more months of lag time, I expect to see near record warm seasons across the United States, perhaps beginning as early as 2024 and certainly in 2025.
June might be the coolest of the next three months, relatively speaking, looking at meteorological trends.
Going deep into June models continue to forecast a deep trough over the eastern third of the country with a cold pocket or cold pockets milling about the Southwest. Positive anomalies are forecast to persist from the Pacific Northwest into the Upper Midwest:
A ridge might try to build over the south-central states by late in June:
Here is the National Weather Service forecast for Summer 2023:
The National Weather Service seasonal outlook appears to be too hot across the Northeast and Southwest unless June’s overall patten were to flip by July, which is possible.
Overall, Summer 2023 will probably verify near average looking at these trends.
Last, we can get another clue looking at prior National Center for Environmental Information ranking and temperature record count data. For this I like to drag out that “Record Scoreboard” (updated through 5/29/2023):
For these data sets all monthly ratios of > 10 to 1 DHMX to DLMN or > 10 to 1 DLMN to DHMX are in bold type. The rankings are for the lower 48 states with the warmest ranking since 1895 of average temperatures being 129 and 1 being the coldest as of 2023. Blue colors represent cold months and red warm. Those months and years with counts close to a 1 to 1 ratio of highs to lows are colored black. Boldly red-, blue-, or purple-colored months, such as January 2020 and June 2021, have ratios of >10 to 1 daily record highs to lows or <1 to 10 daily record highs to lows, and are either historically hot or cold, most of which have made news. All-time record hot or cold ranked months are highlighted in purple.
Notice that so far during 2023 the ratio of DHMX to DLMN is near one to one with slightly above average temperature rankings though April (103). I expect that this trend will continue through 2024 with some relatively cold months interspersed with hot months bringing down averages. After a relatively cold March, record numbers are trending north of a one-to-one ratio once more going into early summer. The ratio of DHMX to DLMN reports are well above 4 to 1 for May, but looking at meteorological models I doubt that this trend will hold for June.
I’m predicting that June will be below average, but July and August will be near average with August being the month most likely to see above average temperatures. Here is the link to avg. rankings per year for the lower 48 states since 1895:
Not all seasons in the near future will see above average temperatures, but seasonal forecasters are beginning to ”chuck it,” discounting colder than average scenarios due to carbon pollution.
Here are all seasons ranked for the last decade:
The last time we had a near average summer season was in 2014. An average ranking on the above chart would be 64.5 as of 2023.
Here is my bottom-line forecast for Summer 2023:
“I think that this Summer will be ranked near average. Carbon pollution is making below average and near average seasons much rarer, but Summer 2023 could be an exception across the United States. I’m going to forecast that Summer 2023 ranking will be around 70 + or – 10, with below average confidence given all of the factors on this post. Confidence is bellow average because betting against hot global warming trends is never a good gamble“
If my forecast verifies this summer will have a similar ranking to that of 2014.
My forecast for Winter 2022/23 of a ranking of 80 was 37 rankings too low since we saw a ranking of 117 for that season. We will see how well my forecast ranking of near 100 for Spring 2023 worked out in a few days.
As of 2023 the top ranking for any month or season would be 129 since climatological rankings for the United States started in the year 1895. Carbon pollution is definitely making below average seasons rarer. As stated, I’m going to guess that Summer 2023 gets ranked around 70 + or – 10, and with below average confidence given all of the factors in this post.
We will see how this forecast pans out around September 8th, 2023.
Here are some other “ET’s” recorded from around the planet the last couple of days, their consequences, and some extreme temperature outlooks, as well as any extreme precipitation reports:
Here is new May 2023 climatology:
Here is more climate and weather news from Thursday:
(As usual, this will be a fluid post in which more information gets added during the day as it crosses my radar, crediting all who have put it on-line. Items will be archived on this site for posterity. In most instances click on the pictures of each tweet to see each article. The most noteworthy items will be listed first.)