One Storm Two Forecasts

Now the good news: Uhhhh…. gimme a minute here. There must be good news.

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 Haven&#185. 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.

&#185 – 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.

16 thoughts on “One Storm Two Forecasts”

  1. Interesting – confusing, but interesting. Is life for a forecaster harder with all these models than it was beforfe?

  2. I guess I am confused…I thought this was a Friday event…not Thursday. See what happens when you stop watching the news?

      1. Snooze ya lose! I will have to pay closer attention! Thanks for the update. Since I have difficulty watching a certain station now, I will have to keep a closer eye on your blog!

  3. Hi Geoff,
    I am still perplexed why they let you go from WTNH. I always loved your liver pate donation at Halloween. Anyway, just wanted you to know that I am still following your weather forecasts as they were always the best!…and delivered with aplomb Also, your daughter was born the same year as mine and one of my daughter’s buddies from New England Ballet was a classmate of Stephanie’s. Just hoping you are well and letting you know that there are a lot of people out there who still appreciate your forecasting.

    All the best!

  4. I love the detail. It’s interesting, and we’re better informed.
    I do think the on-air guys are reading your blog….
    Thanks for treating us like adults.

  5. It’s great to have your forecasts again Geoff! You have a talent of Interpreting the technical and getting down to our main concerns: will school close? Should I plan to work from home? ( when I was growing up you saved me many times by telling us schools would be open when others would dramatize and cry blizzard. If you said so, I had my homework done!) Best wishes Geoff and thanks for blogging!

  6. I enjoy reading your weather blogs. I was a henry margusity blog fan but I think you now take the cake! Keep them coming.

  7. I don’t watch Henry enough. He’s a little more aggressive in his calls than I am, but I think he’s a very smart guy and his videos are always insightful. You’ll learn a lot from Henry! My friends at AccuWeather know it’s killing me to throw a compliment toward State College, but it’s deserved here. Henry’s the real deal.

    That being said, I wrote Henry a few times asking what software he uses to produce his webcasts. Cue the crickets!

  8. Well said, Geoff. I do enjoy his videos when we are expecting a “big daddy” snow storm. I do look forward to your webcasts…missed the first few you did.

  9. HI GEOFF, THIS IS WHAT I MISS ABOUT YOU, WRONG OR ARIGHT YOU ALWAYS HAVE A GREAT EXPLANATION AND A PLACE TO START FROM, nOT JUST JIBBERISH OF SOMEONE WHO HASN’T A CLUE SO MISS HEARING YOUR VOICE BUT AM VERY GRATEFUL YOU ARE HERE !!!!!!!!!!

  10. Thank you for introducing me to coolwx.com. I always wondered where I could go to get my fill of weather stats and models. I’ve always had an interest and part of that stemmed from watching you as I was growing up here in CT. Thanks again!

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