You probably don’t need a meteorologist to tell you that this summer was hot! But now, it’s official: Summer 2023 is San Antonio’s hottest summer on record.
- With an average temperature of 88.7 degrees, summer 2023 is now the hottest summer (June, July, August) on record for San Antonio.
- The Alamo City has experienced the two hottest summers on record, back-to-back.
- August 2023 was San Antonio’s hottest month ever recorded.
- There is abundant scientific evidence that climate change will enhance the normal heat we experience in the summer months AND...
- Three cycles of the natural La Niña weather pattern contributed to the recent stretch of hot summers.
- There is no correlation between a hot summer and a cold/rainy winter but...
- A switch to an El Niño weather pattern provides cautious optimism for healthy rain in 2024.
San Antonio’s Hottest Summer on Record
Meteorological summer is defined as the months of June, July, and August. And despite a rainy and cooler start to June, the rest of Summer 2023 was brutally hot because of a strong and persistent high-pressure system, conversationally known as a “heat dome.”
Summer’s Average Temperatures
The average temperature - or the average of both the daily high and the daily low - for June, July, and August was 88.7 degrees, taking the top spot from 2022 for the hottest summer on record. It’s notable that San Antonio’s two hottest summers have occurred back-to-back. 2011′s memorably hot and dry summer comes in third place.
To tie a bow on the end of this summer, August 2023 is now officially San Antonio’s hottest month ever on record. The average temperature for the month was 90.6 degrees with a staggering average high of 103.0 degrees. For all but two days, the thermometer reached the triple digits...wow!
Consecutive Triple-Digit Days
Speaking of triple digits, this summer also brought the longest streak of consecutive triple-digit days on record.
After an initial stretch of 15 consecutive triple-digit days in July that ended on a day where we found a few storms in the area, we started another streak on July 30. This second streak would go on for 23 days before finally coming to an end on August 22 when South Texas saw rain from Tropical Storm Harold.
105 Degree Days
These heatwaves also proved to be intense as much as they were long in duration, with this year breaking the record for the most 105-degree days by a large margin.
This year, we saw 17 days where a high temperature of at least 105 degrees was recorded in San Antonio, beating out last year where we only had 4!
Possible Relief Soon?
It’s just a matter of time before we see cooler weather in South Central Texas. Here are some general dates that you can keep in mind if the heat’s getting to you:
- The average first cold front for San Antonio falls usually in late September.
- San Antonio’s average first freeze is at the end of November.
While drought lingers on, we’re cautiously optimistic that a switch to an El Nino weather pattern will tip the scale for more rain in winter and early 2024. We’ll keep you posted!
New Normal? The Role of Climate Change on Texas Summers
Yes, I know -- it’s a hot-button topic -- but climate change has played a role in our hotter summers.
This doesn’t mean that every single summer will be hotter than the next. In fact, as recently as 2020, July was actually cooler than normal and we only saw three triple-digit days in 2021. And who can forget the devastating winter storm of 2021?
So, while times of cool (or even cold) weather will still exist for San Antonio, summers on average will be warmer because of greenhouse gasses. In fact, there is abundant evidence that climate change causes Texas temperatures to average about two degrees warmer now than in the 20th century.
And it’s not just the afternoons where the effects of climate change are felt. Because of higher humidity in the air, summer nights are getting warmer in San Antonio, moving average temperatures -- or the average of both the daily high and daily low -- hotter.
With that being said, the reason for our hot summer is not all because of climate change. As usual, with hot-button issues, the answer falls somewhere in the middle. There ARE natural reasons for the above-average heat, and one of those reasons is because of the recent, three-cycle-long La Niña -- which began in the late summer of 2020.
La Niña often creates a dry weather pattern for San Antonio, and when the weather is dry, it tends to be hotter in the summer. Sprinkle on the effects of greenhouse gasses and, voilà, you have record-breaking, back-to-back hot summers.
With La Niña in the rearview mirror and El Niño upon us, there is hope for more rain through early 2024. However... South Texas tends to come out of droughts in a dramatic fashion.
After a dry stretch, it was the Flood of ‘98 that pulled us out of a late-90s drought. In 2015, it was the Blanco River floods that occurred after an extended La Niña drought. History tells us that we should be prepared for flash flooding at some point over the next few years.
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