Posted by: senorwx | September 1, 2013

The Big Boomers

A spectacular thunderstorm ushered in September early today with more than an inch of rain. It was also one of the biggest lightning displays of the year, not to mention the loudest thunder we’ve experienced in San Pancho. My best friend calls them the “big boomers”. The dogs don their thundershirts. More on this later.

August is typically the hottest month of the year here in San Francisco, Nayarit. August 2013 did not disappoint:

  • new annual high temperature of 92 degrees F at 5 pm August 28. (Highest ever temperature in San Pancho was 93 F in August 2009.)
  • rain for the month was less than 8 inches, the least amount since we’ve been keeping records with our Davis Vantage Pro2 in 2008. We have had only about 20 inches of rain so far this year, half the amount of a normal rainy season.
  • the high heat index for the month was within the range of previous August readings, 110 degrees F. Highest ever was 114 in 2010 and 2012.
  • new annual high wind-speed of 23 mph recorded just before midnight on August 15 (well below the all-time 42 mph in July 2009)

Since August is marginally the hottest month in our cozy pueblo by the Pacific you can expect September to be just a bit cooler. Or just a bit less hot. A tiny bit. OK. It is not likely to get any more uncomfortable. Think of today as “hump day” for heat and humidity. But don’t expect any real relief yet. That’ll come in October.

green road in San Pancho

Plenty of rain, sunshine and very few vehicles bring green, green grass to the cobblestone roads in San Pancho.

As mentioned earlier, we had a powerful storm today with 1.11 inches of rain between 2 and 3:30 a.m. A downpour. With pyro-technics to match. The thunder was astonishing. House-shaking. Louder than any Saturday night banda bass drum!

Ever wonder how that sound is created? I did. And thanks to an informative newsletter from the manufacturer of the San Pancho Weather Station equipment (Davis Instruments of Vernon Hills, IL) we have the answer. Most folks think thunder is the sound of air filling in the hole caused by lightning.

Aha! Not so, say the experts: The air is going out, not in, like an air bomb! If you heat up air enough, it explodes, ka-boom! According to Everyday Mysteries, thunder is the sound of a bomb made of air. On its way back up to the cloud, the lightning heats the air around the stroke to 27,000°C. “The heated air is compressed, raising the air pressure from 10 to 100 times the normal atmospheric pressure. The compressed air explodes outward from the channel, forming a shock wave of compressed particles in every direction. Like an explosion, the rapidly expanding waves of compressed air create a loud, booming burst of noise.”

Armed with that information, I hope you’ll you’ll better appreciate the rayos y truenos this month here on the Riviera Nayarit!

(Thanks to the folks at Davis for permission to pirate their newsletter.)

Remember to follow us on Facebook (San Pancho Weather Station) and Twitter (@senorwx).



  1. Manuel just left his calling card. A few days of intense rain.

    My neighbours were in the process of building a house (no roof yet) and for a while they had an indoor swimming pool.


Leave a Reply

Fill in your details below or click an icon to log in: Logo

You are commenting using your account. Log Out / Change )

Twitter picture

You are commenting using your Twitter account. Log Out / Change )

Facebook photo

You are commenting using your Facebook account. Log Out / Change )

Google+ photo

You are commenting using your Google+ account. Log Out / Change )

Connecting to %s


%d bloggers like this: