East of the Rocky Mountains, temperatures have been hot. Texas, Oklahoma and New Jersey experienced record mean temperatures in July. Oklahomas mean temperature in July was 88.9 degrees, the highest for any state since weather records have been kept!
Throughout north Texas, cities broke records for consecutive days of 100-plus degree temperatures. Since June 30, Waco, Texas, has seen temperatures reach triple digits for 44 straight days. This streak broke the previous record of 42 days set in 1980. Wichita Falls did not have a day below 100 degrees from June 21 until Saturday, when the temperature finally stayed below triple digits.
Dallas nearly broke its previous record of 42 days, also set in the famous 1980 heat wave, but a few thunderstorms mercifully rolled in from the north Thursday and kept temperatures in the high 90s. One of my co-workers, Sidney Bob Dietz, lived in Dallas during the 1980 heat storm. He said I spent a lot of time outdoors that summer, and I remember how unrelenting it was. I remember hiding in the shade listening to the cicadas, looking forward to sundown.
Unfortunately, the cooler nights this July didnt provide as much relief in Dallas as in the summer in 1980. Since June 1, low overnight temperatures have averaged nearly 80 degrees. Back in the summer of 1980, the average was 76.8 degrees.
There were nights in Dallas that overnight temperatures dropped only to the high 80s. To put that in perspective, the last time Los Osos saw temperatures that warm was on the afternoon of May 4 when gusty northeasterly (offshore) winds produced high 80-degree temperatures along the coast.
However, the high temperatures this summer in Dallas averaged below the highs recorded during the 1980 heat wave. According to the National Climatic Data Center (NCDC), a few more than 2,700 daytime high-temperature records were broken east of the Rocky Mountains, but more than 6,000 overnight high-minimum-temperature records were broken this July alone!
According to the NCDC, nights have generally warmed faster than days this century.
Why have the nights warmed faster than the days? One possible answer: a warmer atmosphere can hold a greater amount of water vapor. This in turn has produced an increase in cloudiness. When the coastal stratus comes rolling in from the Pacific at night, it acts like a blanket, preventing heat from radiating out to space and keeping overnight lows warmer while keeping daytime highs cooler as the suns light is reflected back to space.
Recent bizarre weather rain and snow in California this June, historic floods along the Mississippi and Missouri rivers, heat waves and droughts in the southern United States, and monster tornado outbreaks have made this year one for the record books. One may wonder are these events due to global warming or are they natural variations due to phenomena like La Niña?
According to retired astrophysicist Dr. Ray Weymann of Atascadero, the answer is both: The continuous accumulation of greenhouse gases in our atmosphere is raising the heat content of the Earths oceans and atmosphere.
This increases the frequency and severity of many of these naturally occurring variations in our climate we call weather. Sadly, these changes are just what climate scientists have been telling us we can expect more and more of.
Weather report:
Looking at the surface charts, a 1,026-millibar Eastern Pacific High will move eastward toward California.
At the same, an upper-level trough of low pressure, over the Gulf of Alaska, will reach the Pacific Northwest by tonight and will quickly push eastward and exit the area Tuesday.
This condition will produce fresh to strong (19- to 31-mph) northwesterly (onshore) winds along the coastline during the afternoon and low clouds, mist and fog during the night and morning hours.
The northwesterly-facing beaches (Cambria, Morro Bay, Los Osos and Montaña de Oro) will range from the low to mid-60s, while the southwesterly-facing beaches (Cayucos and Avila Beach) will range from the low to mid-70s.
The coastal valleys (San Luis Obispo) will reach the mid-70s, while the North County (Paso Robles) will range from the mid- to high 90s.
A ridge of higher pressure is forecast to replace the trough once it exits to the east, and we could see a return to above-normal temperatures by midweek.
Surf report:
Fresh to strong (19- to 31-mph) northwesterly winds will generate 3- to 5-foot northwesterly (315-degree deepwater) sea and swell (with a 5- to 9-second period) today all the way through Friday.
Arriving from the Southern Hemisphere:
Todays 1- to 2-foot Southern Hemisphere (190-degree deepwater) swell (with a 14- to 16-second period) will continue at this height and period through today.
A 1- to 3-foot Southern Hemisphere (180-degree deepwater) swell (with a 15- to 17-second period) will arrive along our coastline Wednesday and will remain at this height and period through Thursday.
Note: Looking at the longer-range charts and models, it appears that no significant wave events will occur over the next 16 days.
Seawater temperatures will range between 54 and 57 degrees through Friday.
PG&E tip
PG&E reminds customers to call 811 to have underground utility lines marked before any digging project.
For more information about 811 and safe digging practices, visit www.call811.com.
Reach John Lindsey, PG&E media relations representative, at pgeweather@pge.com.
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