Sunday, March 16, 2014

Updated Snow Map for March 16-17, 2014

I have updated my snow map to account for the likely shift in heavier precipitation toward the north.


Updated Snow Map


Saturday, March 15, 2014

Late-Season Snowstorm Set to Clip New Jersey

    Another week and another storm…but this is déjà vu for forecasters, as this closely resembles the same situation that occurred with the storm in early March.  A low pressure system will push from west to east to the south of our region.  However, cold, dry air from the north will flow into our region and set up a sharp gradient between those who see snow and who don't. 

Timing
    Precipitation should enter the region Sunday night and last until Monday afternoon.  After that, scattered flurries/snow showers could linger throughout the Mid-Atlantic.  The further south you are, the more likely it is that you see a longer duration in snowfall.

Snowfall

    The dry air being ushered into our region has the chance to keep all accumulating snow south of Philadelphia.  Therefore, in the snow map that follows, I have first labeled an area, within the dashed lines, as ‘Area of highest uncertainty’.  I believe that the line between accumulating snow and non-accumulating snow showers/flurries will setup.  Then, the light blue swath is ‘T-2’, which represents an area where I believe that anything from flurries to 2” of snow may fall.  Finally, the ‘2-5’ swath is where I think the heaviest axis of snow will fall.  Also, warmer surface temperatures will likely affect how much snow actually sticks, but that is one of the challenges with forecasting in March.  In summary, the further south you go the better of a chance you have at accumulating snowfall.


Snowfall Map


Sunday, March 2, 2014

Final Call for March 2nd/3rd Snowstorm

Overview
    Well, this storm has been extremely frustrating to forecast, and it looks like this will be the reversal of what we usually see in a Northeast/Mid-Atlantic snowstorm.  We’ll actually see snow totals increase as you head south, with the bulls-eye area ranging from Maryland into South Jersey.  Just 48-72 hours ago, the models agreed on a big snowfall over North/Central Jersey, but that has shifted well south, and that is why we have the predicted snow totals that we have today.
    
    Anyway, this storm is essentially moving from west to east, and a relatively narrow band of heavier snow will move through the region.  This band has been heavily influenced by the polar vortex over Canada, which has suppressed the biggest snowfall estimates to the south.  Therefore, we’ll likely see a sharp cutoff toward Central/North Jersey where areas see up to a half of a foot of snow and others see almost nothing.  Any change in storm track, no matter how small, from what is expected will alter snowfall totals.  In summary, the further north that you go, the less snow that you will see.  Behind this system, expect very cold temperatures, which has been the other story of this winter along with the high seasonal snowfall.

Timing

    The duration of this storm has greatly decreased for New Jersey, at least.  Scattered rain/snow showers this afternoon will move across the region, then the main bulk of the snow moves in this evening.  Snow will continue throughout the night and into the morning and begin to end from northwest to southeast.  The last of the snowfall will likely taper off by the afternoon hours of Monday.


Final Call Snowfall Map


Friday, February 28, 2014

First Call Snow Map for 3/2-3/4 Winter Storm

First Call Snow Map
*This map is a representation of my first thoughts on totals and is subject to change*

    Essentially, with the storm still being a few days away, it is hard to put too much into this map.  There are still uncertainties about the exact track and of how much mixing will occur, where it would occur, and how much that mixing line would move.  Therefore, it looks like temperatures will be an issue for the immediate southern NJ coast, which is why I placed them at 2-4" because this area will likely just end as snow after rain/mixing.  The rest of the state is really up for grabs.  

4-8+" Range
  This area captures around 75% of South Jersey.  I'll start off by saying that this area's snowfall will be very dependent on the mixing line, which is why I added the '+' in there.  Simply put, the less mixing, the bigger the totals.  The latest model runs have brought colder temperatures and more snowfall to this area, but we'll see if future model runs continue to run with this output.

6-12+" Range
   This range encompasses around 70% of the state and has that pesky '+' sign on the end of it.  It pretty much extends from southern Philadelphia and northward.  As of now, it appears that this is the area where the precipitation will likely stay mostly or all snow, especially the further north that you go.  I believe that, based on the information available, that localized areas in this range could see 12"+.  This will depend on where heavy banding occurs.

    Anyway, these are my first thoughts on actual snowfall totals, and the map is very subject to change and likely will by tomorrow night/Sunday morning when I can likely narrow down the snowfall estimates a bit.

Thursday, February 27, 2014

Early March Winter Storm (Early Thoughts)

Overview
    Last week's warm-up is already a distant memory as bitter cold temperatures have overtaken our region yet again, and another winter storm is making its way toward our area.  All of the models have been in agreement on this storm for a few days now (a rarity), but the battle between the cold and warm temperatures is making precipitation type forecasting extremely tricky.  My first, general thoughts are that the further south you are, the more rain/mixing you see and vice versa as you head north.  The mixing line looks like it will start toward northern New Jersey and make its way down throughout the storm, with all parts of the state under snowfall by the end of the time period.  Speaking of which, the time frame looks to be Sunday through early Tuesday morning, starting from west to east.

    Below are three maps that summarize my early thoughts on the storm and give some general insights...


Current Infrared Satellite Image


    Above is where the general source of our impending storm currently is, which is just off of the Pacific Coast.  This system will move onshore and bring plenty of rain to the west before bringing its energy across the United States and helping to fuel our winter storm.



My Thoughts on the Set-up


    Here, there are a few things going on that I will explain.  First, a cold front will move out of Canada and push into our region around the red line.  There, it will become stationary and this is where the battle of the warm temperatures from the south and cold temperatures of the north will set up.  The red circle is the area where I believe that the mixing line will have its greatest affect as it moves during the storm.  Finally, a series of low pressure centers will ride along the stationary front, as depicted by the L's on the map.



First Call Snow Map (No Totals Yet)

    Essentially, the map pretty much speaks for itself.  Want the best chance of all snow throughout the storm?  Head north!  Anyway, if things pan out according to current model guidance, be aware that we would be talking around a foot of snow, or more, for the hardest hit areas...but that is only if current model information verifies!  The storm is still off the coast, models will likely change a bit, and things will change, which is the usual with any winter storm.




Wednesday, February 12, 2014

Impending Nor'easter Moves Into the Area Tonight

Overview
The major winter storm that has been modeled for several days now is coming to fruition and will impact the Mid-Atlantic/Northeast tonight into Friday morning.  The center of the storm is currently located in the Southeast and will track toward the northeast up the Atlantic coast.  Plenty of Atlantic and Gulf moisture accompanies this storm and plenty of it will fall across our region.  Models even up until 12 hours before the start of the nor’easter’s impacts are all over and causing uncertainty about the storm’s exact track and snow accumulations.  Regardless, the storm will bring a mixed bag of precipitation in the form of snow, sleet, rain, and the possibility of even some freezing rain.  Furthermore, wind gusts of 30mph+ are likely inland, while coastal areas could see gusts of 50mph+ and coastal flooding, as the winds whip off of the Atlantic Ocean.

Timing
                Some scattered snow showers ahead of the storm should be moving in between 9pm and midnight tonight, with the bulk of the snow impacting the area during the overnight hours.  During the day on Thursday, the rain/snow line will likely push inland, bringing sleet and rain to most, or all, of the area.  Some dry air (called a dry slot) may move into South Jersey, bringing lighter to no precipitation, before the backside of the system moves through.  As the backside pushes through, colder air will funnel into the region and accumulating snowfall will likely occur into Thursday night, before the last of the snow tapers off during the early hours of Friday.  Essentially, snow will accumulate overnight tonight and tomorrow evening, with no definite answer as to what exactly will fall during the day tomorrow.

How much?
                Due to the complexity of the system, uncertainty is still there with the battle between warm and cold air.  As the day progresses tomorrow, the rain/snow line will push inland toward Philadelphia and Central NJ.  However, the extent of this movement inland is still unknown, which is why snow total forecasts are still unclear.  My best guess is 6-12” along the I-95 corridor and progressively less as you head toward the shore due to more mixing/rain.  Some models have shown a decent amount of rain/sleet, which is why there is a potential for a busted snow forecast, but some give upwards of a foot or more, so 12”+ cannot be ruled out for the area on the map that I labeled “Are of Uncertainty”.  For this same reason, I added the ‘+’ at the end of the 3-6” zone due to the unknown nature of the rain/snow line tomorrow.  Essentially, if the storm stays mostly snow, upwards of 12”+ is possible but more mixing/rain could lead to the low end of the forecasted ranges. 

                If anything changes, I will post updates and an updated snow map if needed!


My Projected Snowfall Map


Current Radar