Since our prevailing wind during summer is from the south, this wind taps into the humidity coming off the warm Gulf and brings it into North Texas. Inked Gulf in the 1950s Inked Gulf since 2005 In the summer, the waters are much warmer. Keep in mind this is the annual average temperature, not the summer. It is much closer to the Texas coast and much larger. I outlined where the average water temperature of 26☌ (78.8☏) was in 1955-1964 compared with 2005-2017. Scientists at NOAA have shown that the Gulf has warmed 1.8☏ from 1970 to 2020. Well, the Gulf is warming at twice the rate. You might have heard that the entire ocean is getting warmer. This summer it's more like 1 in 6.īut is this a one-and-done kind of anomaly? There is something else going on that might suggest we are heading to more summers like this one. So, in summary, in a really hot summer, you'd expect only about 1 in 300 days to have a maximum dewpoint of 77° or higher. Still, when you start with a dewpoint that high (77° or higher) in the morning, you usually end up with a Heat Advisory or Excessive heat warning that day when the temperature is forecast to hit 100° or higher. I should mention that during your typical summer day, there is vertical mixing of the atmosphere across the afternoon that brings down the dewpoint from the morning when usually the "maximum" dewpoint is logged. This summer, back in June, we had the Heat Index hit 117܄° at DFW which ties for the highest one ever recorded. That's a huge difference and perhaps, hopefully, just a strange anomaly. That's happened only three other days since 1980. This means 20% of summer days so far would be described as super humid, including two days where the dewpoint hit 80°. 14, a total of 12 days logged high dewpoints (77° or higher). Some of our driest years are also some of our hottest summers.īut this year? If this goes down as one of the warmer summers (already in the top 10) and with a top-20 number of 100° days, then something really stands out.Īs of Aug. This makes sense, dry air heats up easier than moist air. Of the total possible summer days (1,365) in these years, only four days had a maximum dewpoint of 77°. Instead of 7% of the days hitting a maximum dewpoint of 77° or higher, in hot years that drops all the way down to about a third of one percent (0.29%). Hourly dewpoint observations only go back to 1954 for DFW, so I was only able to look at 15 of the top 20 years.
When I looked at these top-twenty years, I noticed a big difference with the average since 1980. Hourly dewpoint observations only go back to 1954 for DFW. When I looked at these top 20 years, there is a big difference in the average since 1970. Even though our climate is described as "Coastal Plain" because of our proximity to the Gulf of Mexico, we still get enough dry air from our west to keep the worst at bay. So super-sticky humid air, or a dewpoint at 77° or higher, is fortunately rare in North Texas. Using June 1 to August 31 to define "summer," looking at all summers since 1970, all those summer days, the maximum dewpoint reached 77° or higher only about 7% of the time (325 out of 4,876 possible days). Using June 1 to August 31 to define "summer," I looked at all summers since 1970 and found out that of all those summer days, the maximum dewpoint reached 77° or higher only 7% of the time, or 325 out of 4,876 possible days.
0 kommentar(er)
