A potent storm will form along the East Coast on Saturday upon the arrival of an Arctic cold front. For the Washington region, it means we should expect a turbulent day with rapidly changing conditions.
Wp Get the full experience.Choose your plan ArrowRight
Downpours, plummeting temperatures, wind gusts over 40 mph and snow showers are all possible. It does not look like a good day for outdoor activities.
While it might take until Thursday or Friday to really pin down the forecast specifics, here’s a condensed preview of what we might expect.
Arctic front, ‘bomb cyclone’ to unleash frigid air and snow from Midwest to Northeast
We wake up to rain
As the cold front moves in, rain should develop during the predawn hours Saturday and could become heavy for a time.
While there probably won’t be enough warmth and atmospheric instability for thunderstorms, they are not out of the question.
Story continues below advertisement
“Given strong dynamics and strengthening low-level wind fields, we cannot rule out a gusty line of low-topped convective storms just along the front,” Jeff Halverson, Capital Weather Gang’s severe storms expert, wrote in an email. “[A]ny further westward shift in the [storm] track guidance will have to be monitored, as this could place us deeper into the warm sector for longer duration on Saturday morning.”
Advertisement
The bulk of the rain should end by mid- to late morning, with the potential for up to a half-inch and some locally higher amounts.
Temperatures fall quickly into the 30s
Before the cold front passes Saturday morning, temperatures could reach the low 50s or so. But a sharp drop in temperatures is expected between late morning and midafternoon. The American (GFS) model simulates a drop of 15 to 20 degrees in three hours, meaning temperatures dipping into the 30s.
Winds increase, gusts over 40 mph
As the cold front approaches and especially after it passes and the coastal storm starts to crank up, winds will intensify. Gusts up to 30 mph are possible in the morning before increasing to 35 to 45 mph in the afternoon. Such winds may prompt a wind advisory from the National Weather Service into Saturday night before gusts ease Sunday.
Snow showers are possible but not a sure thing
With temperatures plunging Saturday afternoon and moisture wrapping around the developing storm, snow showers are possible but not a guarantee. Since Tuesday, model forecasts have shifted the track of the storm somewhat more inland. “Such a track is not favorable for snow as the temperatures stay too warm to support snow until the storm is to our north,” wrote Wes Junker, Capital Weather Gang’s winter weather expert. “By then, northwesterly winds behind the storm should help dry up any lingering precipitation. That suggests the most likely scenario for the storm is rain possibly ending as snow showers or flurries.”
Advertisement
Story continues below advertisement
However, the European modeling system still suggests the storm will generate enough moisture on its backside that we have to leave open the possibility of some accumulation, especially north of Washington.
Any snow showers or flurries we see should wind down by early Saturday evening.
It gets very cold Saturday night — wind chills down to near 10 degrees
Frigid air spilling south in the storm’s wake means some of the coldest air we’ve seen in weeks Saturday night. Lows drop to near 20 degrees by Sunday morning (upper teens possible in our colder areas) with wind chills closer to 10 (and even some single digits in our colder areas).