Holiday Outlook – Christmas Flurries Possible

Discussion: This weekly outlook discussion will be in article form since there’s a few things to talk about for the near future. But first, a quick recap of how we got here and how 2024 is wrapping up. Overall, we were warm and dry coming out of the summer and through most of fall. As far as E Equatorial Pacific Ocean goes, the El Nino, that established in late 2023 has transitioned into a current weak La Nina. Some wild winters have occurred with this setup. The main takeaway I’d like you to have from the El Nino Southern Oscillation (ENSO) is that a weak La Nina is not a snowstorm killer, and this ENSO state should be around for the core snowy winter months. Another oscillation that we’re paying attention to is the Madden Julian Oscillation (MJO) which tells us where the best tropical lifting is in the W Equatorial Pacific. The MJO has been a good predictor so far for the prolonged cold/transient warmth we’ve seen since about a week before Thanksgiving. The main takeaway for the MJO is that it indicates the return to a colder pattern for the E US just after the New Year.

Let’s face it, it’s been cold since just before Thanksgiving. I went fishing the weekend before Thanksgiving and I couldn’t believe I was dealing with a thin sheet of ice on top of the water. While acknowledging a few transient warm periods (2-3 days at a time), most of December has featured prolonged colder temperatures. To me, it just feels like we’re heading into a very wintry winter period. Now onto some practical forecast discussion for you through the holidays.

It’s obviously cold as heck right now. It’s not record cold, but it’s cold. Much of NJ is now in an ~84 hour period of staying below 32F, even during peak afternoon diurnal heating. This period began with Friday’s snow/rain event (once the cold front crashed through all precipitation) and should end on Tuesday (Christmas Eve) once the sun is high. Today (Sunday) should be capped in the 20s for most of NJ and tonight will be even colder than last night. There won’t be stiff NW winds but radiational cooling will thrive with clear skies and light winds. I imagine NNJ elevations are going to flirt with dipping below zero while most of SNJ flirts with dipping below 10. Monday morning around 6-7am should be the coldest point of this air mass. We then warm a little on Monday but most of NJ stays below freezing into another colder night (likely 20s for most). The 20s should last until about 9-10am for most of NJ on Christmas Eve morning (Tuesday). On Tuesday morning, SENJ will come above freezing first and NWNJ will do so last.

Before temps rise above freezing Tuesday morning, a very weak and short feature could produce flurries across parts of NJ, mainly NNJ favored over SNJ. A more robust N stream clipper system is expected to track from the Great Lakes into New England during this time. If NJ is to see any of this snow, it will be from a few spin-off squalls on the clipper’s southern side. This would be a very light decaying feature. The Euro, GFS, and RGEM (pictured above) like the idea. The NAM does not. It could be anything from a few flurries to possibly a snow shower. One thing is for sure, whatever falls will stick. But given the fast-moving nature of the feature, I doubt anything more than a flurries/dusting situation is on the table. Temps then rise above freezing by noon for most of NJ and we begin a period of moderation. Areas who saw a thicker snowfall Friday, have the best chance to have snow on the ground for Christmas Day. Otherwise, those who only have coatings now will likely melt on Christmas Eve. We then start the moderating warmup into Christmas Day.

Wednesday through Friday (Dec 25-27) should be the first gear of moderation. Temps should range from upper-30s to upper-40s from NNJ elevations to coasts for daytime highs. Saturday (Dec 28) through about Thursday (Jan 2) should then be second gear of the warmup where daytime highs range from lower-40s to mid-50s from NNJ elevations to SNJ coasts. As far as possible rain, there’s a synoptic rain signal for Jan 30-31 and then a frontal system expected around Jan 2. Like the other recent systems, we’ll gladly take that rainfall. The ~Jan 2 frontal system should then mark the front of the emerging cold wintry pattern.

Jan 2/3 to as far out as I can see on longer-range data (about Jan 10) indicates the formation of a W US ridge, an E US deep/cold trough, and high latitude blocking over Greenland. This would be a pattern favorable for snowstorm development and this is what I’ll be tracking closely over the holidays. Long-range/upper-level jet stream shape on ensemble guidance is what I recommend paying attention to from this point. Your automated weather apps are only looking at the surface and will not reflect the correct situation until only days before. So, pay attention to the upper levels not the surface from this far out. Know that the pattern looks favorable for snowstorm development but does not guarantee one. Fun times ahead.

In English: It will remain very cold and clear until Tuesday morning (Christmas Eve) when flurries, possibly a snow shower, are possible before temps climb back above freezing later in the day after being under since Friday night. NNJ is favored over SNJ for this. Thinking 2am-9am for this possibility Tuesday morning. We then gradually warm up from Christmas Day until about Jan 2. The warmest period (highs in the 40s/50s) looks like Saturday (Dec 28) to Thursday (Jan 2). Seeing some rain Dec 30-31. Then on or around Jan 2, a rainy cold front is expected to end the warmup and return NJ to a cold environment favorable for snowstorm development through at least the first-third of January, possibly longer. Can’t really see anything of value past Jan 10. So let’s stay warm for now, hope for the flurriest situation possible Tuesday morning, take the heating utility break Dec 25-Jan 2, accept the Dec 30-31 rainfall that we need, and focus on any developing snowstorms in the Jan 2-10 period. Everyone have a Merry Christmas or whatever you celebrate. I might check in about the flurry situation Tuesday but otherwise I’ll definitely be back before the New Year to talk about anything worthy. Be safe! JC

Jonathan Carr

Jonathan Carr (JC) is the founder and sole operator of Weather NJ, New Jersey’s largest independent weather reporting agency. Since 2010, Jonathan has provided weather safety discussion and forecasting services for New Jersey and surrounding areas through the web and social media. Originally branded as Severe NJ Weather (before 2014), Weather NJ is proud to bring you accurate and responsible forecast discussion ahead of high-stakes weather scenarios that impact this great garden state of ours. All Weather. All New Jersey.™ Be safe! JC