I was looking forward to a quiet Friday at the office. What was a total non-event 12 hours ago suddenly looks a lot more interesting tonight. While it's still possible we only get a minor amount of snow (flurries or snow showers) there is a rising possibility of an accumulating inch or two along the shoreline around sunset Friday.
A weak disturbance racing east from the Plains is going to be off the Mid Atlantic Friday evening. For the last several days we thought we could see a few flurries here but not one piece of model guidance expected more than that. Starting around midday we saw a few wobbles north and this evening a few models made some fairly alarming jumps north for a 24 hour forecast. Take the Short Range Ensemble Forecast. Look at the huge jump northwest over the past 3 runs with precipitation for Friday evening.
One reason why this bears watching is that much like this morning's snow the snow Friday night looks quite fluffy with cloud temperatures around -15C (or about 5F)!
These kind of systems are my least favorite. Very sneaky, hard to forecast, and have the potential to impact people's plans. At this point I'd be ready for some accumulating snow after about 4 p.m. Friday and know that the evening commute may be impacted especially in southern Connecticut. The extent of impact is still unclear.
We'll keep you updated as things develop quickly.