There’s a difference between forecasting on the sofa and on the TV. I feel much more relaxed on the sofa. As some commenters have noted it might be because I have more time and latitude to explain why I’m saying what I’m saying. This upcoming system needs a lot of explaining!
First the bad news: The two main forecast models still disagree with one another. There’s still no way to make a definitive rain/snow call.
Now the good news: Uhhhh…. gimme a minute here. There must be good news.
I guess the good news is this system is smaller if it’s snow than if it’s rain! In other words a nasty, rainy day or a day of light snow (except the Northwest Hills where everyone else’s big rain might be your big snow).
I’ve attached a model comparison chart for New Haven¹. The newest projections are on top. The reason the precipitation flutters from green (rain) to blue (snow) is because we’re going back and forth from GFS to NAM to GFS to NAM, etc.
The NAM, our snow monger, keeps it’s low pressure center a little farther south and keeps more cold air in place. The GFS pushes some of the cold air out of the way as it tracks farther north.
The NAM is a also faster, but both models start the precipitation around midday Thursday. Both systems start as snow though the GFS gradually turns that snow to rain in all but the highest elevations.
In most cases I choose the GFS over the NAM, but this is too perplexing to declare a favorite.
Neither model calls for much accumulation before the Sun sets. It’s possible some schools might dismiss early, but I wouldn’t blow off studying for a 7th period test (and I am an expert at blowing off 7th period tests).
No matter whether it’s rain or snow Thursday will qualify as nasty–a cold and damp day.
¹ – Thanks to North Branford and Florida State University’s Dr. Bob Hart and CoolWx.com for tonight’s graphic. Bob has an amazing ability to turn abstract numbers into visualizations like this chart.