Saturday, November 22, 2014

"Cutting it kinda close..."

"Cutting it kinda close, don't ya think?"
-Elastigirl in The Incredibles, 2004

6:55 PM EST 11/22 - UPDATED - Scenario Map and Storm Track Probability posted below. Text of the scenarios will be added on Sunday. By Monday we will narrow to 2 tracks, with preliminary snowfall ideas by Monday night and a snowmap by Tuesday afternoon. 

3:42 PM EST 11/22 - Early this week, we posted a report hoping that the weather would not "be a turkey" for the upcoming holiday weekend. However, the pre-winter pattern indicates Mother Nature did receive our memo from October 25*, and appears determined to deliver the first widespread White Thanksgiving to the Mid-Atlantic and Northeast since 1989. (*Hint: It's the post where we said this year, there's better chance of a White Thanksgiving than a White Christmas." 

TEAM STATEMENT: Our composite analyses of several well-known computer models suggests a potentially significant winter weather event may affect much of the East coast for the Wednesday-Thursday period. The timing of this storm could seriously disruptive the Wednesday afternoon and evening holiday travel, if present indications for that time period do not change appreciably.

(Left: Liquid forecasts from NOAA as of Saturday 11/22 show a large swath of precip to affect the East coast Wed night through Friday)

  • The system is still 4-5 days away from affecting any of us. But the untimely prospect of a serious storm arriving on the busiest travel days of the year warranted an early heads up
  • If traveling by air on Wednesday night anywhere along the East coast, it might be strategic to contact the airline now and be aware of your options if the situation deteriorates.
  • It is too early to project when and where snow will fall Wednesday. If planning to travel by vehicle, consider now alternate times or routes you could take if snow develops Wed night in your area or along your route.

TRACK: Our three-outcome graphic above depicts the likely paths, and by Sunday-Monday we can narrow this down to the one solution we expect to be most probable. We emphasize that much can change at 120 hours prior to a storm. Slight shifts can produce major differences, and with a lot of air movement and liquid in play, it warrants close attention.
The Takeaway: We understand how serious this situation would be for millions of people all across the country and around the world. In the words of our headline, this really is cutting it kinda close, in how it could completely disrupt the travel plans of everyone depending on air travel in or out of the Northeast. It's not appropriate to cancel your plans based on a 5-day forecast, but it is reasonable to contact your airline and learn your options if the situation sours quickly on Wednesday.

TEMPS: Despite an expected spike into the 50s and 60s by Tuesday, another push of Arctic air will return to the region. Some computer scenarios show a cold rain on Wednesday changing to snow before nightfall. Were the coastal low to develop as shown on Tue-Wed, it would tap a large reservoir of nearby cold air due to the recent heavy snowcover in the Great Lakes to New York state. The European model, notable for accuracy in long range calls from recent winters, shows sub 34 F temps from Virginia north by 7 PM Wednesday.
The Takeaway: Were these temps to occur during a "nor-easter" setup, the result would be wind-whipped heavy snow to hit major East coast interstates of the Northeast corridor at the absolute worst possible time: Wednesday night.

LIQUID: The NOAA Weather Prediction Center's latest liquid projections, (shown above) prepared by actual meteorologists using input from several model sources to convey what we call a "broad brush" look at what's possible. A general 0.50" to 0.75" of liquid is, at this point, the most probable outcome for the I-95 corridor. 
The Takeaway: A slight shift to the west by Wednesday would bring much heavier precipitation, and possibly, heavy snow with low visibility, to the expected high traffic volume areas of the map. 

NEXT UPDATE: Our team will keep close watch on this developing story, and post updates in the early morning and early evening, with a mid-day reassessment each day. 

Forecasters Foot, Connor Meehan, Mike Natoli, Joey Krastel (MD Team); Justin Barker and Andy Smith (VA Team)


BioPat said...

Sounds like this could be an interesting week. I've been too busy to pay attention to current forecasts; just trying to get to Wednesday at noon for a well deserved rest. I know the models are showing a fairly significant liquid availability and if the temps cooperate travel conditions for the travelers could be impacted.

Andy, Southern York County Pa said...

GREAT THANKSGIVING BLIZZARD OF 2014? Why not? These are no longer the musings of a random weather hick, but the latest Euro says yes sir! 1-2 feet of snow up I-95 is possible, if not probable if we believe the Euro. Maybe my early return from hibernation is justified. Either way the snowblower has been primed since the first week of November, and the 5 day period before Thanksgiving seems to be delivering as scheduled, and could be a time to remember!

Andy, Southern York County Pa said...

No matter what the final outcome will be, Wednesday looks like a tough travel day. We should have a better idea of the likely ground truth by Monday morning for Wednesday. Euro was impressive, but not the final word.

BioPat said...

Interesting thoughts Andy. I agree Wednesday's travel may be quite challenging, I am thankful I'll be staying close to home until Friday. The Canadian model is not as impressive as the European and other models equally put this a bit more out to sea following the trend of hurricanes last summer. So, no question this bears watching over the next few days.
I'm excited with the chance of snow always and like you have the snow blower fueled and ready to be called into action. Most of all I am looking forward to our Foot's Blog back in motion for another fun filled season!