January 10: Riding the Temperature Roller-Coaster


Kind of a tricky forecast today, with competing weather elements trying to warm us up or cool us down…winds have shifted to the east, which is a cooler direction — so we won’t be as warm as we were yesterday. The main source of uncertainty is related to the amount of cloud cover we’ll see overhead today. Some clouds spread in last night, but not everywhere — as a result, temperatures were all over the place this morning, with cooler readings under the clear skies and warmer temps under the clouds:
We’ll flip that around today: cooler under the clouds, warmer where you see more sunshine. Here’s the temperature pattern I expect this afternoon:
My confidence in that temperature forecast is tenuous at best, because I just have no faith in how the forecast models are simulating the extent of the clouds. The best-case scenario is that we’ll see more sunshine and substantially warmer temperatures…that’s what the HRRR model thinks will happen:
The worst-case scenario is that the clouds will thicken up and keep us closer to our normal high of 50, as depicted here by the American GFS model:
Either way, we’re still talking about a pretty pleasant day overall — maybe not quite as nice as yesterday, but I’m certainly not going to complain after we spent so long in the deep freeze!
The warmer-than-normal temperatures will continue through the rest of the work week, but we’ll bring in a pretty good chance of rain as well. Showers become more likely in the afternoon and evening both Thursday and Friday, with some thunderstorms added to the mix Friday evening. The North American Model’s radar simulation has a pretty good handle on the pattern:
I’m not overly concerned about our severe weather potential Friday evening — right now it looks like the best chance of storms will move in a few hours after sunset, which means there won’t be much instability (“storm fuel”) in place. However, there will be quite a bit of wind energy overhead, which means our severe weather threat won’t be zero. The Storm Prediction Center’s ensemble model (think of it as a super-blend of a bunch of different forecast models) shows a 20% chance of at least borderline severe weather ingredients:
The “analog” forecast (comparing Friday’s forecast pattern to similar historical patterns) shows the best chance of stronger storms remaining off to our southwest:
At worst, I think the Storm Prediction Center might include us in a “Marginal Risk” (level 1 of 5) of severe weather. If we get some stronger storms, straight-line wind gusts up to 60mph would be the main threat. I wouldn’t worry about it at this point — just plan on staying weather-aware on Friday.

Once the storms move through, colder air will start invading central North Carolina again:
Highs in the low 50s on Saturday will occur early in the day, then we’ll be in the 40s (at best!) the rest of the weekend:
Dry weather and slightly below-normal temperatures will prevail through the first half of next week. All in all, not bad for mid-January…even if all of the ups and downs in the temperatures forecast are a little bewildering.

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