Good afternoon. Here’s another update on weather for the Houston Marathon, and unfortunately the outlook at this time still favors warm conditions for the morning of January 15.
The GFS model
The North American model is downright warm. According its ensemble output, the GFS model forecasts a 0 percent chance of low temperatures 40 degrees or below on Sunday morning, which would be ideal for long-distance running. Conversely, the model predicts a 60 to 70 percent chance of a high temperature of 70 degrees or above that day. This still leave some wiggle room, but the outlook is not good. Essentially we’d be looking at start-time temperatures in the 60-65 degree range with high dewpoints.
The European model
The European solution is slightly more optimistic. The graphic below is busy, but instructive, so let’s take a moment to explain it. The bottom panel shows “minimum” temperature forecasts for a given six hour period. I’ve indicated the period for Sunday morning’s low temperature, and the range of 50 ensemble outcomes peg it anywhere from 30 degrees to 70 degrees.
However the highlighted green area shows the most likely range of temperatures that morning, from the upper 40s to the upper 60s (the model average is 59 degrees). Similarly the model’s most confident range of high temperatures on Sunday afternoon runs from 60 to 75 degrees.
My take on the European model is that it’s forecasting about a 50 percent chance of significantly warmer than normal temperatures, 60 degrees or higher at race time. There’s probably a 25 percent chance of lows from 55 to 60 degrees, and a 25 percent chance of lows below 55 degrees (fingers crossed!).
The only positive thing I can say is this: We’re still nearly 11 days away from marathon day. That is a long time in weather forecasting, and predictions this far out are simply not locked in, even when the models seem pretty consistent. While a warm race day is certainly most likely, it is far from certain. But damn, I have to say the prospect of running a race in the 60s and moderate to high humidity is very, very far from enticing.
Tomorrow I’ll start looking at rain chances as well.
(Space City Weather is sponsored by Westbury Christian School for this month)
Posted at 4:20pm CT on Wednesday by Eric