Blasts of cold likely to mean a wintry Thanksgiving week in the D.C. area
Thanksgiving week promises to feel more like winter than fall as strong back-to-back cold fronts plow through the eastern United States. In the D.C. area, the first cold wave is predicted to arrive Sunday, with a second, stronger blast potentially coming Thanksgiving eve.
Behind the first front, highs may hover in the chilly 40s Sunday and Monday, whereas in the wake of Wednesday’s front, highs could even be a hair colder.
The average high temperature the week of Thanksgiving in Washington is in the mid-50s. Temperatures should be lower than that much of the time.
With this cold air in place and disturbances passing by, the region has a chance to see its first snow flurries of the season late Sunday and/or in the wake of the midweek cold front.
The first cold wave — arriving late Saturday into Sunday
There is some uncertainty on the timing of the arrival of the first cold front and its intensity. The American model, the GFS, sweeps it through Saturday night and is stronger, whereas the European model holds off its arrival until during the day Sunday and is weaker. For this reason, the American model predicts colder weather on Sunday than the European model, with highs in the 40s rather than the 50s.
Sunday is bound to be windy once the front punches through, with gusts over 25 mph a good bet.
The American model even hints that a few snow flurries could zip through the region Sunday afternoon and evening as a weak disturbance cycles through the cold air.
The cold air is fully immersed over the region Monday, when highs are likely to to be in the 40s — closer to 40 if the colder American model is correct and closer to 50 if the European model is more accurate.
The second cold wave — arriving Wednesday into Thanksgiving
Temperatures will try to creep back up to normal on Tuesday before the next big cold front approaches. While the European model predicted a weaker front arriving later Sunday, it predicts a more powerful second front, arriving sooner with this next blast. It forecasts the cold front blows through by early Wednesday, when highs only reach the upper 30s and stay that cold through Thanksgiving Day.
The American model, on the other hand, forecasts the front’s arrival to hold off until Thanksgiving morning — meaning milder highs into the 50s on Wednesday and rain showers on Wednesday night. Cooler air in the 40s then spills in during Thanksgiving Day.
Due to its stronger push of cold air as well as a disturbance passing by, the European model might suggest a few snow flurries could fly early Thanksgiving Day — but that’s a very low confidence prediction.
Because Sunday is still more than five days away and Thanksgiving is more than a week away, the details regarding the timing and intensity of these fronts is murky and needs to come into better focus. By later this week, we should have a better idea on exactly how cold it’s going to be, when, and more details about any precipitation.
Both models predict the North Atlantic Oscillation will be in its negative phase through much of next week, which generally signals chillier-than-normal weather.
Source: Local Weather