Challenging Christmas Forecast - NBC Connecticut
On Ryan's Radar

On Ryan's Radar

First Alert Meteorologist Ryan Hanrahan Gives You His Take on Connecticut's Weather

Challenging Christmas Forecast

On Ryan's Radar

NBC Connecticut First Alert meteorologist Ryan Hanrahan gives you the science behind the forecast and shares with you an in-depth look at the weather impacting Connecticut.

Video Forecast

Ryan On Twitter

Afternoon Forecast for December 19

(Published Tuesday, Dec. 19, 2017)

To say that there's a lot of uncertainty about the Christmas forecast would be a big understatement. A huge push of Arctic cold will be moving south out of Canada while moisture will be moving northeast out of the Gulf of Mexico.

Earlier I tweeted about the difference in our computer guidance for 12/25. Obviously it's a lot more complex than just picking a random computer model out of thin air but the bigger take away is that there is a tremendous amount of spread in possible outcomes.

Looking a bit more closely at our afternoon guidance we can see a few things. The most important part of the forecast is how far east the storm coming up the coast gets - for instance an offshore storm is more likely to produce cold and a wintry mix here in Connecticut while an inland storm (commonly referred to as an inland cutter) would bring rain. My gut feeling is a warmer/western solution is most likely with mainly rain. Below are the GFS aned European Ensembles (both models are run 20 and 50 different times, respectively, to produce a range of possile outcomes). 13 of the 20 GFS ensembles produce more than an inch of snow in Hartford on Chritsmas while about 25% of the European Ensembles do.

The current forecast I have for Bradley Airport is 38F and rain on Christmas but this may certainly change in the coming days. Stay tuned!