Summer Heat About Average in '09; Air Quality, West Nile Infections Improve

Share |
(Sacramento, CA)
Monday, October 5, 2009
Johnnie Powell with the National Weather Service says the summer heat ended up exactly how forecasters expected it to.
Powell: “This summer, we’ve had 22 times that it was above 100, and that’s about normal, so we’re actually on track. What may have seemed cooler this year is that we only had one of what we call major heat wave. It was more manageable because the 100s were spread out.”
That let the nights cool off and kept Delta breezes blowing, which, in turn, helped air quality. Last year, the Sacramento Metropolitan Air Quality Management District reported 20 unhealthy or very unhealthy air days – mostly due to the heat and hundreds of dry lightning fires. This year? Just six – and none of them the highest risk. That’s largely attributable to fewer fires this year. But Powell says the weather helped too.
Powell: “The reason you get stagnant air is when we get into heat waves where we get no air flow.”
Then, there are those pesky West Nile Virus-carrying mosquitoes, who love the hot weather. Gary Goodman is with the Sacramento-Yolo Mosquito Vector Control District. He says the number of West Nile cases in humans is down sharply this year – both regionally and statewide.
Goodman: “Typically, heat or very hot days tends to amplify the virus, and we didn’t really have that this year.”
In fact, human infections in the four-county Sacramento region dropped from 21 last year to just three so far in 2009.