SAN DIEGO — You’re probably noticing the mugginess, especially at night — maybe even running the air conditioning a bit more. Well, you can blame these hot and humid conditions on monsoons.
The monsoon season for us in San Diego can start as early as July but most of the activity is in August and September.
Each year is a bit different and this year we are getting a bit more activity in terms of thunder, lightning and isolated rainfall for our mountains and deserts.
“The heat that builds over time in Phoenix, in Las Vegas, gets to almost like a boiling point where the whole weather pattern, the winds, that brings this moisture up from Mexico literally shifts,” said Alex Tardy, meteorologist with the National Weather Service in San Diego. “Some years it shifts only just for a short period of time like two years ago but last year and this year we’ve seen a more significant shift.”
Tardy, along with a team at the local National Weather Service office, keep a close eye on the instability and moisture in the region that sometimes trigger severe warnings.
“Even in Southern California, we get dangerous lightning and flooding from the monsoon,” he said.
We need the rain, but not all at once.
It can lead to major flooding like we’ve seen on the Las Vegas strip and record flooding in Death Valley where more than half of the yearly average rainfall for that area fell in just a few hours.
At the same time, showers can delay extreme fire weather.
“Right now, our fuels out there — they were critically low. And now they are at stable average levels, which means we can still get fires, but they shouldn’t be big,” Tardy said.
It only puts a Band-Aid on worsening drought conditions.
With San Diego County mountain areas short more than 10 inches of water this year and the city of San Diego short 4 inches, the monsoons won’t be enough.
“The expectation for this upcoming winter is to fall short again, and that would be three years for Southern California and four for Northern California, and right now we’re seeing unprecedented water supply levels on Lake Mead, Lake Powell: lower than they’ve ever been historically,” Tardy explained. “And we already saw that two years ago and in California as well. It’s widespread in terms of the drought and with La Niña expected again, I hope it’s wrong but it’s not looking promising.”
In other words, we are expecting a third consecutive winter season of La Niña which typically doesn’t bring abundant rain.
It’s not uncommon but California is entering the winter in extreme to exceptional drought conditions in many areas which could prolong the fire season.
