The following is a conversation overheard in the weather office this week. Unfortunately, both ends of the conversation were mine.
So, what if last week’s storm system had happened in a month or two? How much snow/ice would we have seen?
Pretty much what happened this time, assuming it was the same system.
You know what I mean…it’s typically colder in December and January, so surely we would have seen some widespread and heavy snow or ice.
Who says it would have been colder? Our average high temperatures in the dead of winter are in the lower 50s for the Upstate. Our highs for the end of last week were in the mid 40s. So it’s entirely possible that the same storm system would have had the same temperatures and the same result.
All right, humor me. What if it had been colder?
We wouldn’t have had the same storm system. So I can't pretend to accurately answer the question.
First, colder air is not as capable of holding moisture as warmer air is. So, assuming our temperatures were five to ten degrees colder…the lowered ability of the air to hold moisture would have lowered the amount of precipitation we would have received. I can’t tell you the three inches of rain we had at GSP would have translated to an inch and a half of ice or two feet of snow; the available moisture would not have been the same. The result would be different. It's comparing apples to frozen oranges.
Secondly, if the cold air had been stronger…the jet stream (which marks the dividing line between cold and warm air) would have been farther south than it was. Which means the low pressure center that helped force our precipitation along would have traveled farther south. This would have meant the deepest moisture would likely have been to our south. The likely result would have been lowered the total precipitation here; depending on the exact track, we might have only seen light precipitation! Of course, such a track may have meant a better chance at a full blown Nor’easter, which would have made Thanksgiving travel a complete disaster in the Northeast.
So just admit to me you don’t know what would have happened...
I think that’s what I’ve done here. Weather is all cause and effect. And if we change the “cause” just a little, we may see giant changes to the “effect”. Again, we can’t compare apples to frozen oranges. This storm was the “apples”. Frozen oranges would have given us a completely different result. And some chipped teeth.Buzzkill.