Long-Term Forecast Ideas


A little over a month ago, we decided to put out a forecast like we’d never really done before detailing some long-range ideas about how summer was fading fast and much colder-than-average weather was on the horizon (see Ensemble Signal of Cooler Weather Ahead).

That idea panned out pretty well! There have been no more 90º days since early September, and the over-all temperature regime has been cool lately. September was 2.2º F cooler than normal in Huntsville (that even includes the hot weather early in the month), and October has been 4.4º F below normal through the first 8 days. In fact, this morning’s low temperatures in the mid-30s are the coldest since March 10th; that was the last time Huntsville International Airport recorded a low in the 30s. The coldest temperature in the entire Tennessee Valley this morning was reported at Winchester, Tennessee’s airport: 34 degrees!

Now that we have had a period of cooler-than-normal weather, the pattern is shifting to bring us back to near or even slightly above the averages for the next few weeks. Remember as you read this: patterns give us broad ideas about weather over weeks or months, but patterns do not always indicate any one particular weather event on a given day. That means while we are looking at above-average temperatures, there is still enough wiggle room in the actual day-to-day weather to make it very chilly now and then!

Here’s the latest Canadian NAFES Temperature Anomaly Forecast for October 17th through October 24th; unlike the past month or so, there is no big blue blob covering the South, and that means a more even temperature pattern for the next two to three weeks. No excessive cold is likely, but no excessive heat is expected either! We will be near “normal” for the remainder of October: highs in the 70s, lows in the 40s (with occasional warmer and cooler days now and then).

The American ensemble forecasts back up this idea; the probability of a temperature exceeding 75º F on any day through the next two weeks is only greater than 60% through October 17th; after that, there is only a small chance of getting warmer than 75º through October 25th:

Speaking of October 17th in particular, there is reason to believe there could be a threat of some heavy rain and maybe some strong storms either in or nearby to the Tennessee Valley around the 17th or 18th. There are absolutely no details available to share with you right now because it’s too far away; however, it gives you a good, long heads-up that the Fall severe weather season could start a little early this year. This is the morning run of the GFS model; it is not overly impressive, but we have seen some model flip-flop over the past few days in this period. That means we’ll be watching trends to see what develops!

Even longer-range ideas suggest that November could be abnormally warm and a little wetter/stormier than normal. If it does turn into a stormy Fall, we’ll be here to keep you abreast of everything happening in the world of weather!

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