Wednesday / Thursday Storm (Wednesday Afternoon Update)

First and foremost, our storm is really taking a toll in the Southeastern US. Snows and ice are really hitting an area hard that is not normally accustomed to this. I can only hope everyone down there follows their forecasts and have plans done accordingly.

For our area up here, we are about 10 hours away from the start of our storm. As you can see, we are dealing with a very large storm. We can see a direct influence from the Gulf Of Mexico feeding directly into our low pressure. This will be a very intense and large storm. This will also probably be our longest duration event for the year.

My going thinking has been 4-8" for the area and then a switch over to a mix and possibly rain. I do think we switch back to snow as the CCB (Cold Conveyor Belt) swings through the area. The CCB is the back end of the "comma" head of the storm. As the storm pushes through, this will swing over the area. How much additional will that add? Well, like everything else with this storm, it depends.

I will say, the models have been all over the place with this very large and complex storm. My 4-8" is my best guess trying to make sense and from experience with these types of storms from prior years. Growing up in NJ, most of the large intense storms bring a period of a transition to a mix or rain. As the storm moves east of the area, we go back to snow till the end of the storm. While the model guidance has been less than stellar, I do hold out hope for the short range models, the HRRR and the RUC models which will be in their range later on tonight.

While my call is 4-8" with a transition, the confidence of that is low to medium. I think we are going to see some very impressive snowfall rates through the area. We have a storm that is going to dump between 1-2" of precipitation. The question is going to be figuring out, how much of that is snow, mix, rain. If it were all snow, we would be looking at 12"+ easily. Now, how fast do we transition? Do we transition? does it stay as sleet? freezing rain? rain? Do we go back to snow? What kind of precipitation rates do we have? These questions will all be answered starting in 10 hours. Until then, I am going with the 4-8" as my conservative estimate, with a strong feeling that the totals may end up higher than that.

So, while those are the accumulation questions, there will be other questions that will also need to be answered. I said that we are dealing with a very large and dynamic storm. Even if warm air moves in, and the surface temps get above freezing, if we have a period of very heavy precipitation, we can remain snow if the upper atmosphere is still below freezing. This will all have to be tracked as well with the storm. Obviously, if the rates are not that impressive, or the upper atmosphere and surface are above freezing, we will have rain. Speaking of dynamic......I fully expect there to be a good number of reports of thundersnow tomorrow. Maybe even as early as the early morning hours.

So, the specifics.

Snow moves in around midnight to 2am. It will snow very heavily in the early morning hours, with the possibility of thundersnow. Accumulations by the time we wake up will be 3-6". I expect to pick up another inch or two and then a transition to a mix will occur as the storm moves closer and some warmer air floods the upper atmosphere. I do think though we will remain sleet for a while. During the afternoon, precipitation may actually stop or become very drizzly. To the evening hours, I expect the CCB to intensify and move through dropping more intense snowfall before ending towards midnight. Exactly how much will depend on how the low pressure bombs out, and how much moisture can be thrown back over the area.

Anyways, those are my thoughts and concerns as of now. As always, I will be posting on facebook and twitter throughout the day and night.

Stay Safe!

Wednesday / Thursday Storm (Tuesday AM Update)

Overnight model runs have concluded and now I am looking forward towards today noon model runs. Last night, I explained on facebook where we were before the model runs. Overnight, the NAM was less amped, the GFS moved a bit west (but overall had a much better organization). The EURO was pretty steadfast on its track showing a front end thump of snow and then a transition to a mix and possibly rain. Today the models continued down the same roads and the NAM, GFS and Canadian models all bring in a period of sleet/mix/rain to CNJ.

With that, it has become more and more clear that our area will see some transition over to sleet/mix/rain etc. The projected track (on any of the models) will make it very difficult for us to remain all snow. Areas NW of 95 should do really well and will cash in with widespread areas of 12"+. Those areas would be places like Reading, the Lehigh Valley, NE PA and possibly NW NJ. I think areas down in CNJ are looking at a nice front end thump of snow 4-8" (possibly more) and then a transition over to sleet/mix and then possibly rain. There could also be a change back to all snow on the tail end. Coastal areas, there is a full moon expected as well Thursday, and with a developing low pressure coming up the coast, spells disaster for coastal flooding. 

In any case, a shift in the models by 50 miles east could make quite a difference. Same with a shift 50 miles west. With that, those are my general ideas. There will be more updates to come. We are still 36 hours away so there is some time for some wiggles. If you know anyone down in the NE Georgia, Central SC and NC areas, they will be receiving an epic ice storm. Make sure those down there are prepared and follow their latest forecasts down there. We still have people up this way without power from our storm last Wednesday. Also, areas not accustomed to snow could be in for some surprises as well (South Central VA, W NC etc). Also, DC looks to actually be in a pretty decent spot up our way for a pretty decent storm as well. 

More to come

A Look Ahead Into Wednesday / Thursday

With this clipper over for today, the next focus will be on a developing storm for the Wednesday - Thursday timeframe. The Canadian and EURO models have been hinting at a low pressure tracking from the SE coast, up to the Outer Banks and then east of Jersey to the "benchmark" (or just inside). The benchmark is a noted area, 40N 70W, where most of our significant snowstorms move through especially for New England). Also, this looks to be a much slower moving storm than we have had this year and will also effect a larger area.

The GFS has come around to the idea and has the storm, but has it further into the ocean and only scraping the East Coast. Tonight, the NAM also shows the storm, although we are at hour 84 on the 84 hour model (not the greatest at this range) but I am encouraged to see it there, and very amped up. There will obviously be some questions with track, intensity and so forth with this storm, but this is definitely one that has my attention. This will effect a large area, from the Gulf States to the Southeast to the Mid Atlantic through New England.

So, time to watch the continuity from run to run and see further cohesion in coming up with a track. There will be many updates coming, so please follow along on twitter and facebook!

January 2-3, 2014 Storm (Wednesday Noon Update)

First, HAPPY NEW YEAR!

Well, here we are once again with a very challenging forecast which will more than likely go down to another nowcasting event. There are a number of moving parts to this storm, and the overall strength will not be known for some time. We have an interaction that will occur between the subtropical jet (currently the precipitation along the Gulf States and the Polar jet (currently the precipitation through the midwest into Detroit). As seen here:

As the storm progresses, we will see an interaction occur. When, and how quickly these parts interact and eventually phase, that will determine how much snow we are looking at. The NAM model paints an earlier phase and a bigger storm for our area, and the GFS model paints a later phase, and as a result, a bigger storm over New England. In any case, the GFS model still paints a plowable event for our area.

GFS model- Showing a quick intesification for our area, but moves out rather quickly in the next frame and hits NE.

1am Friday:

 Friday 7am: (notice brunt of the precip off shore and over eastern NE

NAM MODEL

Quicker phase, really hammers our area

 Still has moderate to heavy snow over our area at 7am Friday (notice our area has the brunt of the precip):

So, the big question will be when does this phase occur. And unfortunately, it will have to be now casted tomorrow night. Either case, we are looking at a storm which will drop a couple inches. Here is where I am now, if we get that earlier phase, I think our area would be looking at 6-10" of snow. If we get that later phase, I think we will be looking at 2-4 (SNJ) to 3-6 (CNJ-NNJ). Its going to be another thread the needle event, with another tough forecast. Don't be surprised to hear amounts going up and down by the media stations. I do believe that Watches and or Warnings will be issued for MT Holly's forecast area this afternoon. In addition, Areas just to our north, we may actually have the B word watches issued. Winds will definitely be a factor, and if they can get high enough, we may meet that criteria ("Blizzard conditions" technically occur when strong winds (at least 35 mph) combine with either falling snow or snow on the ground to reduce visibilities to 1/4 mile or less for at least three hours.)

The other dangerous part of this storm will be the temperatures. We are dealing with a polar airmass with this, so even though the morning tomorrow will be cool, temperatures will plummet tomorrow night and it could infact get down to the teens and be snowing, 20's all the way down to the coast. The danger with that, is #1, its cold and #2, salt does not work as well in much colder temperatures. #3, snow ratios will be higher (usually 1" water = 10" of snow). We could be looking at 15:1, 20:1 or higher! In any case, I am tuned and am looking forward to seeing this come together!

Tuesday / Wednesday Update

Models have been pretty consistent over the past day in regards to Wednesdays storm. Its looking like precipitation will actually make its way into the area around 7pm on Tuesday Night and be around until Wednesday Night before finally pushing out. This is looking like an all rain event, and we could get a healthy dosing. 1-3" generally across the area can be expected. The low pressure track, as shown on both the NAM model and GFS model show a track right over Philadelphia and Trenton to the NNE. With this track, we will have to watch for a potential dry slot to set up around our area, which could lead to a decrease in the amount of rain.

Once the storm pushes out, it will set up another round of cold air to move in. Thanksgiving will be cold and windy. The Macys Thanksgiving Day Parade will be interesting with the winds and the floats. More to come and any changes will be noted!

Buckle Up!

Earlier in the week, I mentioned how we were heading into a roller coaster and we have done just that. We started out earlier this week in the upper 60's and temps crashed. Today and tomorrow will be in the 50's. Sunday and Monday will feature some of the coldest high temps this season! 

Once we get to Monday, all eyes will turn towards the Thanksgiving holiday. Overnight weather models have shown better agreement in regards to a developing storm potential. Thanksgiving is one of the heaviest travel days in the US, so extra attention should be payed to the situation. 

At this point, it will be a rather "thread the  needle" type event that we are so used to. As of now, low pressure moves up from the Carolina coast. Rain will move in and then transition over to snow possibly. Shore areas will have rain and winds to contend with. 

This will also be a quick moving system with no blocking to keep the storm at a crawl. It's a rather progressive and quick hitting type storm. This will once again be a storm where one area will be raining and 30 miles away could be getting puked on by snow. 

In any case, it's got my interest and I will be watching the model runs. As always, updates will be forwarded!