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This is the number one question I’ve received the past few months. WHY IS IT STILL HOT OUTSIDE!?
Houston is on track to experience its warmest fall on record, and it’s not even close. Since the start of meteorological fall in September, our average temperature has been 79°F. The previous record, set in 1931, was 74.9°F. Specifically our average high is 89.3°! This is crazy high! Our average morning low is 69°.
With more than two weeks remaining before the end of the month and the final tally, a major cooldown is still not in sight in the next eight days.
Why has it been so warm?
Reason #1 - The jet stream:
One of the main drivers behind this season’s warm weather pattern is the jet stream. In a typical fall, the jet stream moves south with cold fronts. This year, it has stayed farther north, preventing consistent cooling. Our recent cold fronts have been especially frustrating, bringing only brief, slight cooldowns before temperatures rebound into the 80s after a couple of days. Wednesday night’s front is a perfect example of this pattern. In fact, our high temperatures won’t even dip below average this week.
Reason #2 - The blocking effect of high pressure systems:
Adding to the warmth, areas of high pressure have blocked much of the chilly air from reaching the region, acting as an atmospheric barrier and sustaining the warmer temperatures. Depending on the position of the high, we can receive either warm, humid air from the Gulf or warm Pacific air from the west, as we saw on Monday and Tuesday. This high-pressure blocking contrasts with the usual brisk air that defines the fall season and has further contributed to the extended warm spell.
Reason #3 - Living in a warmer world:
Since 1970, the United States fall season has warmed 2.4°. In Houston specifically, we have 22 more days above average in the fall and temperatures are 3.6° warmer. According to Climate Central, this year’s warm is not an exception. It’s part of a longer warming trend.
There is hope on the 10-day:
Over the next eight days, temperatures will remain above average. However, by the middle of next week, the jet stream is expected to dip south for the first time this season.
This shift will bring cooler temperatures, with highs in the 60s and morning lows beginning in the upper 40s. Check out the video below for more details.
