Tuesday, August 13, 2013

The 'August Cool Snap' Theory

The cool snap predicted for later this week is no surprise to some people in the Carolinas.

Over the years, I've heard several different versions of the "August Cool Snap" theory, which states that Charlotte's brutal summer heat usually is broken -- for a few days, at least -- by cooler weather at some time during August.

I first heard about it from the late Gerry Leland, who worked at The Observer for 37 years before retiring in the 1990s. He believed the cooler temperatures came in the second week of the month.

Attorney Dick Huffman in Salisbury reminded me about the theory again Tuesday morning. He was married 30 years ago today, and he recounted how he quieted his bride-to-be's fears about a hot mid-August day by telling her the weather would be fine.

"To my amazement, it was wonderful, with highs in the upper 70s or low 80s," Huffman recalled.

He says that many years, he has noticed a spell of cooler weather sometime around his anniversary, although he says it doesn't always take place.

Meteorologists say a Canadian high pressure system will limit daytime highs to the upper 70s and lower 80s Wednesday and Thursday, and thick clouds and rain could do the same thing Friday and Saturday.

So I went back and looked at August weather over the past 10 years, and like many other statistical studies, it's a matter of interpretation, to some degree.

Do you call it a "cool spell" if daytime highs are 85 to 87 degrees, but morning lows are around 60 -- about 10 degrees below average.  Lows of 60 degrees signal very low humidity, and that would feel very nice in the middle of August.

Here is what happened the past 10 years, and I'll let you decide on this issue of the August Cool Snap.

2012 ... From Aug. 13-17, we had a stretch of days with highs in the mid 80s, but morning lows in the low 60s. Humidity levels were quite low.

2011 ... After hitting 90 or more on nine of the first 10 days of the month, it got more moderate. Morning lows on the 16th and 17th were near 60 degrees.

2010 ... Forget it!  There was nothing remotely close to a cool down.

2009 ... The high on Aug. 12 was only 74 degrees, and morning lows from Aug. 13-16 were in the mid 60s.

2008 ... The first 10 days were hot (mostly 90s), but it was a lot cooler on the 13th and 14th. Aug. 13 had a high of 76 after a morning low of 60. The next day, the high and low were 82 and 61. Temperatures stayed moderate for the next week, before turning hot again at the end of the month.

2007 ... Worse than 2010. There were six days of 100 degrees or more, and Charlotte hit at least 90 degrees every day in August.

2006 ... A definite cool down from Aug. 11-13, with a high of 73 on the 11th and morning lows in the low 60s.

2005 ... From Aug. 7-10, highs were only in the mid 80s, but it was warm at night.

2004 ... The poster child for the August Cool Snap theory.  The morning low on Aug. 7 was 50 degrees (a record), and it was 55 on Aug. 8. Daytime highs were only 80 degrees.

2003 ... The beginning of the month was moderate, with highs in the low to mid 80s. It got hot late in August that year.

12 comments:

Anonymous said...

Steve - Don't you have some real reporting to do - other than this drivel?

Tord Lincoln said...

Hahaha. Maybe this is what Steve is paid to report. I suppose this could be interesting trivia, but it is meaningless for 2013.

lkmnews said...

I enjoy reading Steve's knowledgeable posts about the weather. Those who prefer not to are welcome to read other "important" information such as sports stats. ;-)

David said...

We enjoy the backyard pool and motorcycling in the summer. You must admit-this summer has been quite a disappointment for both of these or any outdoor activity.

Steve's explanation of the Jet Stream working with our familiar Bermuda High is spot on. Certainly better than the standard litany of "It will rain some every day for the next week and we won't tell you why because you can't deal with the science".

Good stuff steve- Keep it up!

Tord Lincoln said...

This report on the past ten years of August weather, as relatively useless as it is for 2013, is actually more interesting than sports stats and stories at almost any moment in the present.

Please provide more Steve!

Anonymous said...

Thanks for printing this, Steve. Can you do, or have you done, a similar list for early December and wintery precipitation?

Anonymous said...

Absolutely believe it and even in those brutally hot years there were less brutal temps during the 2nd week for at least a couple of days.

Anonymous said...

I'm happy to see this. I've long been a fan of the (2nd week in) August cool snap. Wish I'd been tracking it all these years.
The only down side is when we get a lot more heat afterwards, sometimes into late September.

Anonymous said...

Steve - I enjoy reading your columns. I like that you include a little bit of history and statistics that can show trends. It is nice to read something about our weather that isn't the average weather forecast. You write about things that affect us all. It even affects the jerks who give you a hard time down here in the comments.

For the jerkholes complaining about what Steve writes - get a life. No one made you click on the link. If you dislike it so much why take the time to comment. It must be a pretty sorry life to make pointless complaints. Maybe complaining about others makes you feel better about your own pathetic life.

Anonymous said...

Steve - I enjoy reading your columns. I like that you include a little bit of history and statistics that can show trends. It is nice to read something about our weather that isn't the average weather forecast. You write about things that affect us all. It even affects the jerks who give you a hard time down here in the comments.

For the jerkholes complaining about what Steve writes - get a life. No one made you click on the link. If you dislike it so much why take the time to comment. It must be a pretty sorry life to make pointless complaints. Maybe complaining about others makes you feel better about your own pathetic life.

Anonymous said...

Hey Anonymous @5:51 PM...why don't you take your own advice? You are quite proficient at complaining and being a "jerkhole" yourself. Why don't YOU get a life? Hypocrite.

Shaw said...

Haha...Steve's groupies (Anonymous @ 5:51 PM) are here to "defend" him.