I know everyone wants an update on the winter storm threat that looms, so let me talk about it first. Then I will get to the brutal cold. There continues to be a threat of a significant storm system on Tuesday into Wednesday. A trend has developed today, but there is no certainty that this trend will hold. Some of the more reliable modeling has taken the storm track and shifted it to our east. What I believe is happening is that the models are beginning to pick up on the fact that the colder air will be too strong of a force and this cold air will block the storm from cutting up directly at us. We just now have to be careful that the cold air and blocking pattern is not strong enough to avoid an event for our area all together. I still would like to see another two or three rounds of model data before I am confident that the wetter/icier vs. white solution will not take place. But it appears confidence is growing for a colder storm across Central and Southern New Jersey which would favor increased chances for frozen precipitation.
I want to clarify a rumor I have been hearing today about this storm. If you are on the colder side with a storm passing to your east…you will automatically have snow. This is FALSE. In the Summer time, occasionally you have a coastal storm that passes us by. However, WE DO NOT see snow. When one says that we see the colder side, it is implied that the air flow will be from a direction that typically draws in or maintains a cooler regime. If the storm tracks to our west, we would be on the warmer side because usually the air flow will be from a direction that typically brings in warmer air. To be more specific, an eastern storm track brings in northerly wind component of some sort and a western storm track brings in a southerly wind component of some sort. The air around an area of low pressure is counterclockwise in the United States.
The 12z GFS and 18z model shows very little in precipitation with the storm tracking well to our east as it is being blocked by a very cold, arctic air mass. Prior runs showed a significant snowstorm with some mixing involved along the coastal counties.
The 12z ECMWF or European model shows a good size snowfall for our region, but not the most dramatic of storms we have seen in the past year. It too gives an idea that there will be some sleet and freezing rain down at the immediate coastline and perhaps in the Southeastern NJ areas.
The 12z and 18z NAM continues to show a strong low pressure area developing in the Southeastern United States. This low then moves northeast on the model. However, the model only goes out to hour 84 and therefore I cannot get a good feel as to where the model brings that low center. The NAM I feel has done a fairly good job this winter and so tomorrow I will take this model and the output somewhat seriously.
The energy is just beginning to enter a region of North America where there is much better instrumentation and sampling of the atmosphere. This will be critical in determining where exactly this storm will track. Equally as important will be the clipper passing by tonight that will set the stage for the exact placement of an area of high pressure to our north. Until we verify where this exactly sets up, there will be lower confidence in the forecast. This will be the key in determining how much cold air is locked into place and where the blocking sets up.
At the present time, I will discount the one model indicating a complete miss. This storm has the potential to bring three to six inches of rain, 12 inches or more of snow, or serious ice accumulations. It just depends how all the cards fall into place. It is worth repeating that although I am dismissing it for the moment; we just now have to be careful that the cold air and blocking pattern is not strong enough to avoid an event for our area all together.
Moving on from the subject of a storm potential for a moment, I hope you stayed indoors as much as possible today. It was downright frigid outside. Much of the day was spent with temperatures in the teens. The sunshine hid behind several cloud layers this afternoon. Without the sunshine, it felt even chillier! The brisk wind today gave us single digit wind chills during the day which made it feel all the more brutal outside! The European Model last weekend was dead on with the idea of an arctic attack striking us this weekend.
A clipper system will pass to our north overnight into Sunday Morning. It will bring clouds to our region. Therefore, temperatures will not drop like a rock tonight. The wind will relax quite a bit tonight and pick up very briefly on Sunday as the clipper slides a cold front throughout area. Since the air mass is very cold, single digits to lower teens are still likely for low temperatures.
On Sunday, there will be morning clouds followed by afternoon clearing. The morning clouds and very cold start in this type of air mass point to another day with temperatures well below freezing. Highs in the middle twenties seem reasonable. There is a slight chance of a snow squall or a snow flurry with the passing front, although most of the high resolution models point to a dry passage. I think the better chances of this happening will be in the northwestern portions of New Jersey. Sometimes these snow showers do make it down to about Route 1 or Route 130.
On Sunday Night into Early Monday Morning is when I suspect we will see the coldest minimum temperatures. Skies will be clear, there is some snow cover around (especially into North-Central New Jersey), and we will have calm winds. The heart of an arctic attack will also be over us. These factors point to single digit lows being possible in the cities of New Brunswick and Camden with lower single digits elsewhere. Some of our coldest suburbs could definitely go below the zero degree mark for a time. This includes Somerville, Chatsworth, Lakehurst, and Millville. This cold is the kind that can cause serious water main breaks in the urbanized areas of New Jersey. Everyone will also be using their heaters and this is typically when we see some fires break out in homes. The fires that do break out will be difficult to contain as the extremely cold temperatures will cause ice to form around the scene very quickly when firefighters use water to douse the flames. A range of -5 to 5 seems reasonable. Being that I am thinking the wind will be calm, wind chills should not be a factor. However, if you get just a slight breeze it could be pushing wind chill advisory criteria.
The latest information is suggesting that Monday could actually be colder than Saturday and Sunday! I think temperatures will have an extremely difficult time recovering from the overnight low temperatures. The core of the arctic attack may not retreat until later in the day. I am going to forecast a high of 19 degrees for Monday. Yes, it may make it to 20 degrees. But the idea here is that outside of the urban heat islands….teens will most likely be the outcome.
One more note: there could be a lull Tuesday and Wednesday at some point. It is too early to nail down whether this will be the case.
Other notes: I am also a part-time forecaster for the site http://phillyweather.net . Saturday is my day of responsibility for this site, so a more regionalized forecast for the Delaware and Lehigh Valley can be found there today and every single day. I will also be filling in for the site founder next week as he is going to be out of town on business. So check that site out as well. Brian, a founder of the site http://cnyweather.blogspot.com is also a colleague on that site and will be filling in as well. If you headed up to Oswego at any point in the future, be sure to check out his forecast for that area.
I will remain committed to tracking this potential winter storm throughout the remainder of the weekend and next week.
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