So About Next Week…

Tonight's 00Z European Model Forecast for Next Wednesday Evening (http://www.meteo.psu.edu/~gadomski)

I’m not one to go bonkers when it comes to any particular storm (in fact, you read me discussing how I would be apt to NOT hype next week a couple days ago). But I think now it’s obvious we have something rather significant showing up here. The three major models tonight all went nuts for the middle of next week, showing an absolutely massive storm slowly rolling up the East Coast. When all three models lock in on a massive storm, that very often means that they’re right. Models struggle and they can be a bit inconsistent at times, but when it comes to the extremely large, widespread or historic sized events, they are usually quick to hit on things. I’m not saying that next week’s storm will be historic, but there’s no question we’re now looking at a significant to major event for much of the Mid-Atlantic and Northeast.

Tonight's 00Z GFS Model Forecast for Next Wednesday Evening (http://www.meteo.psu.edu/~gadomski)

So what are the details? Well, it’s far too early to speculate, but we’ll do just that because we can. Based on tonight’s model runs, we’d be looking at a snow to mix/rain ending as snow event from I-95 to the coast (and even a little further inland from there), with extremely heavy snow/mix possible from the Smokeys north into Upstate NY and interior New England. The storm is also extremely slow moving. For example, the precip begins in Philly on tonight’s Euro run at about Midnight Wednesday and does not end until about 9-11 AM Thursday. Snow moves into the Albany area around 9 AM Wednesday and doesn’t depart until after Noon on Thursday. These aren’t forecasts…they’re just examples of what the model is showing and emphasis on a 24+ hour event.

Tonight's 00Z Canadian Model Forecast for Next Wednesday Evening (http://www.meteo.psu.edu/~gadomski)

The other issue then is track. Tonight’s runs are up along or just inland from the coast. That is extremely unfavorable for heavy snow from DC-Boston…that’s a wet track, not a white one. However, if you look closely at each model’s ensemble mean, you’ll see the track is still fairly far offshore. What does this mean? That the operational models *may* be on the extreme west edge of the track forecast envelope. I wouldn’t go shouting from the rooftops just yet, but it’s something to keep in mind.

We’ve seen a lot of storms the last couple winters, but this one I think is the most impressive looking in terms of physical size and slow track. We’re in a powder keg pattern right now, and this may be the fuse that helps things explode. I’m not going to get into details of the meteorology behind what’s happening right now, but we need to watch things very closely over the next few days. But each model run has looked more impressive with this storm, not less impressive, and that trend may continue as we get closer.

Unfortunately, I’m heading out of town Friday afternoon…well, actually I’m moving, but taking a week or so to drive to Texas, so my updates will be much more infrequent. However, make sure you “like” State of Occlusion on Facebook, as I’ll post updates each night/morning with the latest information. This really could be a big time event, so stay tuned!

Advertisements

Briefly Updating Snow Chances

Just wanted to throw down a brief entry to outline snow chances more specifically.

Snowfall Forecast for the Friday Storm (click to enlarge)

To the left is my first and last call snow map for the Thursday night and Friday “storm.” Again, this will be a quick mover and really not a big system at all. It may get its act together to throw back some briefly heavy snows into New England, and dump mainly a 2-4″ sort of snow back in the red area. Most other areas will only see a coating-2″, with an isolated 3″ amount report or two possible. Timing…arrives in the Philly area after midnight Friday and exits the Boston area Friday after sunset. Quick mover.

Next week’s storm continues to show up on the models today. It does look as though this will be a rather large and strong storm. But the overall track is going to be what is impossible to nail down for several more days. I do expect someone in the interior Northeast to see a decent shot of snow, some areas with potential for a mix, and some areas with a cold, raw rain potentially. I still would avoid hyping this one in the big cities, as it’s far too early to even try and guess how it will unfold specifically. A lot of what does happen is dependent on how a system plowing into the Northwest US this weekend behaves. I’ll be traveling much of the next week, and I’ve been watching forecasts for northern New Mexico fluctuate between sunny and dry to heavy snow for the last several days. Why do you care? Because that shows you the volatility of what that Washington/Oregon storm will be doing…we simply can’t say, and in order to peg down who gets the snow next week in the Northeast, we need to know what will happen out west. So stay tuned.

————-

State of Occlusion is on Facebook! I’m posting some additional cool links and videos, quick model status updates, and snow maps earlier than you’ll get here. All kinds of cool stuff available on our “Like” page. “Like” the blog by clicking here!

Here We Snow Again!

Snowfall Forecast for Tues/Wed.

There’s the snow map at the left. Here’s some ideas by region.

– Boston area could see some very high snow amounts of 16-20″, depending on the exact track of the storm. If the storm tracks just right, they could get slammed, as some models suggest. Interior Southern New England right now would appear to be the jackpot, but I wanted to emphasize the risk to the Boston area. Parts of CT and MA may see some 20″+ amounts, with generic 8-16″ amounts as you approach the coast (some coastal areas and the CT River Valley may see lesser amounts). Cape Cod will likely be close enough to the storm to mix or change to rain. This will cut down on snow amounts a bit there. Additionally, wind will crank on Wednesday, leading to blizzard conditions in parts of New England.

– Metro NYC area/NE NJ won’t be the jackpot this time around. However, this still appears to be a respectable, business hampering snow. Think of the last system that went through, think of post-Christmas, and expect this storm to end up somewhere in between the two. There will yet again be a very sharp cutoff to significant snows, somewhere within the I-287 corridor. Blowing and drifting snow will occur in this region Tuesday night and Wednesday.

– Southern NJ will be close to the center of the storm, so I do expect the possibility of a mix. It also appears the storm will really explode a little too far away from this area this time. I still expect a respectable 4-8″, with the potential for higher amounts in mainland Cape May, Atlantic, Burlington, and Ocean Counties (6-10 perhaps?). Coastal sections may even see less, primarily in Cape May County. If mixing for some reason does not occur, tack on an additional 2-4″ to these forecast amounts. Blowing snow will cause a few problems Wednesday.

– Philly/Trenton will be solidly in the 4-8″ range, with potential for higher amounts (8-12) as you get closer to Trenton/New Brunswick and slightly lesser amounts as you slide south and west of Philly. Blowing snow will be a problem on Wednesday.

– DC/Baltimore appear to be in the 1-4″ range, with again potential for higher amounts in the northeast corner of the map. Much of the interior back through OH/MI will average 1-4″ as well, with potential for a few 4-6″ amounts in spots, depending on how things shake out.

And that’s that! After this storm, it appears we’ll head into a relative period of calm in the Northeast. So enjoy this if you like big storms and snow. Winter is certainly not over though, so stay tuned.

————-

Just a reminder… State of Occlusion is on Facebook. I’ve posted some additional cool links, quick model updates, and snow maps early on that page. “Like” the blog by clicking here!

Quick Weekend Snow Risk Assessment

Not much to say beyond what was said yesterday. Just looking at the models today and going off past experience, I feel this first system Friday-Saturday is not going to be a backbreaker on a large scale. I think we’re dealing with a more localized storm in areas more suited to handle heavy/surprise snow…an Alberta Clipper system that starts to explosively develop off the New England coast, which may for some point carry one of my favorite descriptions: A ballistic clipper. These types of storms can really hammer areas north of I-80 if the situation is right.

Snowfall Risk Assessment for the Northeast Friday-Saturday (Click to enlarge)

So anywhere from about Rochester or Syracuse eastward is fair game for this possibly overachieving. Right now, I think the odds of the “clipper” overachieving are highest in the Catskills, but this could easily be extended north toward the Mohawk Valley or even the southern Adirondacks and Berkshires. The secondary area is where the intense coastal development will take place, which is off the Massachusetts coast, possibly putting Portsmouth, Boston, Providence, and Cape Cod under the gun for a period of heavy snow. I’m non-commital on that area though, and more enthused with the idea of parts of the interior being “surprised” by this. For now, you can see my highest risk areas. These may be expanded or contracted later. Additionally, the area of 3″ accumulating snow could end up pushing a little further south, but if I lived south of I-195 in Jersey, I wouldn’t be too concerned or enthused for snow at this point. I think this first event will be primarily a north of I-80/east of I-81 storm. I’ll keep you posted.

We still have this other system showing up on the models for midweek next week, and that one I’m still not writing off or committing to at this point…but I will say, given recent model trends and the overall pattern, it would make sense that someone will see a significant winter storm for the middle of next week. Stay tuned.

———–

Don’t forget, State of Occlusion is on Facebook! I’ll post some additional cool links and snow maps before they’re published here on that page. “Like” the blog by clicking here!

The Boxing Day Blizzard

Well, it’s underway, and miraculously, there haven’t been any dramatic changes in the forecast in the last 12 hours. The main areas of concern to me seem to be:

  • Cape Cod/Providence/Boston/Long Island: How much falls as sleet/rain vs. snow, thus cutting down snow totals there. The low should ride the coast from about Montauk to Martha’s Vineyard, so this will both lead to a mix/changeover scenario on Cape Cod/southeast Connecticut/Rhode Island and may even have to a dry slot cutting down totals in general. Will this make it as far north as Boston? Doubtful, but we’ll see.
  • Jersey Shore from LBI south: There could also be some mixing issues here. In my experience there are almost always mixing issues in this region when a low passes this close to the coast. So this may cut down totals, and I’ve lowered the range a little to 7-14 (down from 8-16). It’ll still be a good storm, but the combination of a little less precip and this mixing scenario has me cutting back a smidge.
  • Philly-Morristown-Albany: The biggest question of all is regarding how far west the heavy snow will get. And this corridor stands the most to gain or lose depending on the exact amount the precip shield barges inland. I could see this being as little as 6″ in Philly to as much as 12-16″ there depending on the exact track (same goes for the I-287 corridor in Jersey and I-87 from Newburgh to Albany.
  • NYC-Hartford-Interior New England: This could be an absolute wallop for places like Worcester, the Berkshires, the Litchfield Hills, etc. A lot of potential for a lot of snow in these areas, and there could be a cluster of significant 20″+ amounts anywhere between NYC and Boston depending on where the best mesoscale banding sets up.

Lastly, the wind impact from this cannot be stated enough. This is a storm which is going to see its barometric pressure fall from about 996mb off Cape Hatteras to perhaps 970 mb or lower south of Long Island. In meteorological terms, we call this an atmospheric “bomb.” In other words, it’s going to be rapidly deepening, and it will be progressing along close to shore. This is going to create absolutely ferocious winds all the way up the coast and rather far inland. With everyone’s Christmas lights up, coupled with heavy snow, the wind has the potential to cause a LOT of damage/mess. It may not be a bad idea to secure some of the holiday displays Sunday morning. There will also be the potential for significant power outages as well, so be prepared, especially because temperatures will drop into the low 20s to teens Monday night and Tuesday morning, with wind chill on top of that.

Travel is going to be next to impossible and is not recommended, especially from Northeast NJ into New England after about 9 AM-Noon tomorrow. And it may be that this is the case throughout most of eastern PA/NJ/DE/eastern NY as well. This really to me seems like last February, shifted a couple hundred miles further north. So please use caution if you have to travel, and be prepared for numerous road closures/states of emergency by Sunday evening.

7:30 AM Sunday Update: I would likely trim some of the snow totals back east a bit in the 3-7″ range, esp in NY/PA. The storm is moving along at a decent clip. The real intensification takes place this evening…that’s when the “blizzard” aspect will begin to take shape. In terms of the actual amounts, I might be apt to trim back south Jersey/Delaware a bit (more like 6-12 now to me). Overnight models (not going to read into them too much at this point) did cut back snow totals there to the 6-10″ range). Still looks good that the bullseye is between NYC and Boston..but not IN NYC or Boston. Boston may end up on the lower end of my forecast range, but inland areas will push the higher end. The western extent of the snow between the Delaware River and the Hudson River is going to be EXTREMELY sharp now it appears. Could easily go from 2-4″ far west to 12″+ over a very short distance. Whether that gradient is centered over the Delaware Water Gap or Denville in North Jersey, I’m still not sure. Still a tough forecast. Keep an eye on things throughout the day. Also, from northeast NJ into New England, the bad travel may not start until more like 11-2, rather than 9-12.

1:30 PM EST Update:  Everything still on track. Morning model guidance and current radar trends validating a major storm that’s underway. Latest SPC Mesoanalysis showing that the storm is rapidly deepening off the NC coast as it gradually pulls north. This will bring blizzard conditions to most of coastal NJ/Delmarva and inland to about Rt. 206. The blizzard conditions will spread north into NYC and New England this evening. The worst of the weather will be bounded on a line south of I-90 in New England and east of I-287 in NJ-I-87 in NY.

If you live in Southeast Jersey, snowfall rates of at least 1″/hour are occurring and those heavier bands will continue to push onshore from time to time this afternoon and evening. Heavier snow continues to gradually push inland, and to be honest, the snowfall map from last evening doesn’t look too bad at this point (though I’d still shift the 4-8″ area a little further east). Some totals so far include Somers Point at 6″, ACY at 4.3″, a little over 3″ at Ocean City, MD, and 6-10″ in the Hampton Roads area of Southeast VA and parts of Northeast NC, back through Raleigh/Durham. The DC/Baltimore areas have been for the most part “shut out” of the storm so far, and it’s not looking likely that those areas will be hit nearly as hard as others north and east.

Travel and conditions in general will continue to deteriorate this afternoon. Be safe!

Here’s your map for new snow tonight-Monday (click to make it bigger). Feel free to add any questions in the comments, and if you like the updates or have any comments/ideas for future items, let me know! And Happy Boxing Day!

Final Snowfall forecast for Boxing Day Blizzard (click to enlarge)
The storm is moving along at a decent clip. The real intensification takes place this evening…that’s when the “blizzard” aspect will begin to take shape. In terms of the actual amounts, I might be apt to trim back south Jersey/Delaware a bit (more like 6-12 now to me). Overnight models (not going to read into them too much at this point) did cut back snow totals there to the 6-10″ range). Still looks good that the bullseye is between NYC and Boston..but not IN NYC or Boston. Boston may end up on the lower end of my forecast range, but inland areas will push the higher end. The western extent of the snow between the Delaware River and the Hudson River is going to be EXTREMELY sharp now it appears. Could easily go from 2-4″ far west to 12″+ over a very short distance. Whether that gradient is centered over the Delaware Water Gap or Denville in North Jersey, I’m still not sure. Still a tough forecast. Keep an eye on things throughout the day.