Space City Weather

The unofficial forecast for the 2016 Chevron Houston Marathon

Having turned 42 this year I decided to try and run a marathon for the first time. Perhaps it was a way to push back against father time. Certainly registering for the Houston Marathon proved a cheaper antidote to a mid-life crisis than buying a fancy convertible.

As I trained this fall I soon discovered the importance of weather in distance running, and most critically humidity. Cold and dry weather made running 10 or even 15 miles a breeze. (Well, sort of.) But even in December, when dewpoints were in the upper 60s, running five miles was pure misery. So I feel you when it comes to weather on January 17.

We’re still 19 days from the Houston marathon, and the major global forecast models only run out to 16 days. Truth be told, they have very little accuracy after about 10 days, so we’re still more than a week away from what might be considered a “moderately” accurate forecast for the marathon. With that said we can draw some inferences from seasonal weather models, which I will now do.

NOAA makes monthly forecasts, and right now its outlook for January calls for a slightly better chance, than average, for colder-than-normal temperatures in Houston. But this isn’t terribly helpful because the first half of January could be freezing cold, and the second half somewhat warmer than normal. When we’re out there sweating our butts off on the morning of the Houston marathon, we won’t care if it was 25 degrees the week before.

Fortunately some seasonal modeling has higher resolutions than this. One of the models is NOAA’s Climate Forecast System (v2) which makes temperature predictions for 5-day chunks. Here’s its latest forecast for the period of January 16 through January 21st. Reading the map below, it shows temperatures a good 6 to 7 degrees F above normal for Houston.

(Weather Bell)

Now that sounds pretty bad, but I would not read too much into the forecast. Two days ago the very same model was forecasting temperatures several degrees below normal for the Jan. 17th time frame (yeah!). The normal low temperature on Jan. 17th in Houston is 43 degrees, with an afternoon high of 63 degrees.

Here’s the bottom line: January in Houston will probably be colder than normal, but that doesn’t give us much useful information about the weekend of the Houston marathon itself. Not yet, at least. However beginning on January 4th I will be providing daily weather updates for race day, so be sure to subscribe to this blog (box on right-side of this page, follow me on Twitter, or like my Facebook weather page.)