Are we really done with 90° for the year?

So I made a small wager with my co-anchor Dion Lim that we will not hit 90° plus for the remainder of 2012. This is part meteorology but also part a gut feeling. The weather pattern for the next 7-10 days certainly doesn’t show anything close to 90° in fact it looks very pleasant. It also appears that the weak El Niño will keeps thing near average for the rest of autumn. The average high is now in the low 80s so hitting 90° becomes harder and harder. Yet it certainly isn’t unheard of either to hit 90 in mid to late September or even early October. So lets take a look at the numbers for 90° weather from September 11th on in Charlotte, NC.

9-11-2012 11-08-03 AMThe latest we have ever hit 90° or higher is October 13th and the 13th is also the last record high of 90° or higher for the year. The record high for October 13th is 91° set in 1954. So unless we set a new record after that the latest ever will stand as October 13th since records started in 1879.

On the right you can see the average number of days we hit 90° between now and the end of the year. The average is almost 4 but the mean number is 3. So we should expect about 3 more days of 90° or higher in any year, but just last year we had 0 in that time frame. In 1954 the year we also had that record high of 91° on the 13th we had 14 more days of 90° plus. In 2010 we did it 7 times that was a warm autumn followed by a cold winter.

In case you are wondering we hit 90° 49 times this year which is 6 days above average. We also hit 100° or higher 5 times which is 4 days above average in Charlotte, NC.

Here is the graph of 90° + since 1939 if you see negative numbers that’s because data is missing or bad for those years.

9-11-2012 11-08-17 AM

  • Though my official policy is “never trust the GFS for anything”, it hasn’t shown a 90F+ day in the 16-day output for awhile now. If anything, it has trended cooler for the last several days. I think it’s a pretty safe bet to say that we’re done.

    • wxbrad

      Justin, yeah pretty much the way I feel too and the pattern just looks cooler. If we were going to be in the 90s it would most likely have to be this week or next climatology wise.