Winds will continue to pick up later this evening continuing through the overnight with the latest high-resolution models showing some of the strongest wind gusts occurring Monday morning as the sun rises (provides mixing). Wind gusts between 45 and 60 mph are possible, especially from the immediate Washington Metro Area points north and east. Winds will begin to relax Monday evening as the pressure gradient begins to unwind behind New England’s second blizzard in less than a week. *This has not been a good winter for DC, Baltimore, Philadelphia and New York*. I guess it was New England’s turn this year as they missed out on our blizzard last January.
The next system to watch for us snow lovers involves the evolution of where a southern-tracking low pressure system over Texas eventually tracks.
Check out the latest upper trend upper-level (500 mb) chart for Wednesday night (images courtesy TropicalTidbits):
- The image below shows the last 15 runs of the same model (Global Ensemble Forecast System) ending with the latest run from 12Z (7AM EST) this morning.
- The upper level trough (blue colors north of Toronto) is firmly in place and is deepening as we head towards Wednesday night; meanwhile a southern wave can be seen over Texas.
- The trend has been for the upper-level trough to build in a bit to the west while the southern system over Texas advances a bit further east with each run. Why do we care? To get some snow from the system impacting Texas tomorrow we need phasing to occur (or in plain english for both the upper-level trough over the Mid-West and the wave of low pressure over Texas to at least line up. Preferably we would want the wave over Texas to get out ahead of the trough so that it can become absorbed (phased) with it… pulling it’s lift and hence precipitation into the Mid-Atlantic versus it heading straight out to sea.
- As it stands this evening it does not currently appear that the system over Texas will move fast enough to become phased with this digging trough over the eastern Great Lakes.
- What could happen over the next 48 hours is that the storm system in Texas could move a bit faster while the upper level trough remains in place, if we can get this southern piece of energy over Texas to speed up… our chances of some light snow increase. If the system over Texas can really speed up… we could get an accumulating snow event. It is something to watch but my hopes currently are not very high.
So if we look at the latest surface models (Canadian, GFS and Euro) for Wednesday let’s see what I am talking about (and just how frustratingly close things evolve):
- DC snow-hole as storm (999 mb low) near Augusta, Georgia scoots out to sea (if it could only move faster, the trough could pick it up delivering some accumulating snow to the DC Area)
- This is the latest 18z run (image below) showing how the system is currently forecasted to get left behind as it weakens and heads out to sea.
- The Euro also paints a gloomy picture as it keeps the precipitation over the south from getting pulled up into the upper-level trough over the Great Lakes. Notice that “540 line” across central Virginia. Here is yet another story of where the temperatures at 5000 feet would be supportive of snow but the precipitation remains disconnected from the cold air. Meanwhile, the mountains block much of the Lake effect snow showers from reaching DC and Baltimore due to the “rain/snow shadow effect” of down-sloping winds. This is why we have to either have a strong clipper that tracks 50 to 75 miles south of us or a coastal storm (Nor’easter) over Hatteras that tracks toward Cape Cod to get a decent snowfall across our area.
So there you have it as of this evening I am not hopeful for a decent snow event but am at least hoping that given that we are still 72 hours away from Wednesday evening… maybe… just maybe the wave of low pressure over Texas will eject to the east faster… providing the potential of some light snow or snow showers on Wednesday night into Thursday. We shall see. I will provide updates to come on Twitter @DCstorms (www.twitter.com/dcstorms) and my website (www.DCstorms.com) if things start to go in our favor.
Check out Justin’s blog as well (I follow him and he has a great website!!) as he may be providing some analysis this evening on how the pattern mid-week could play out.