Synopsis:
High pressure will nose in from Canada tonight and clear the skies out. Temperatures will fall below freezing throughout.
A storm with heavy precipitation will move toward the area this weekend. Any sun will give way to clouds on Saturday. The snow or a mix to the South should move in between 4pm-8pm on Saturday from West to East. An accumulating heavy snow (a few to several inches depending on location) is likely just inland and including the City before a mix occurs Saturday night. The latest computer guidance continues to suggests a warm slug of air will work in changing the snow over the rain along the coast and a mix of freezing rain, sleet and snow inland as the storm moves from Washington, DC and hugs the coast just off NJ (map above). This warmup will occur for about 8 hours into early Sunday morning.
The 3kM NAM model (2nd map above) is coldest of all the models and puts out the highest snowfall. It also has the critical 32º mark (the thin red line over Northern NJ and to the East) farthest to the South. This model does well a lot of the time with micro synoptic weather patterns. I cannot discount it. An ice storm is possible after the accumulating snow near this freezing line. Also heavy sleet will occur just North of the Freezing rain line. The legend of the colors of the precipitation type is at the bottom of the map. I cannot stress how 10 to 20 miles will make all the difference in the world between plain rain and serious ice. It’s called a coastal front along the area of low pressure. Where the wind stays more of a Northerly component-watch out.
Flooding rains are possible where the precipitation stays liquid. One to two and half inches of liquid precipitation is expected.
A flash freeze is likely on Sunday as the push of Arctic air works in. Any leftover precipitation may go over to a period of snow on Sunday. It all depends on how quickly the Arctic air funnels in and how much precipitation is remaining. Most of the models have sped up the end time of the precipitation to the midday hour. I agree with this. The sun will most likely return on Sunday for a part of the afternoon.
To recap: As of right now, it looks like a burst of moderate to heavy snow at the onset of the storm later Saturday and into Saturday night for much of the area. Several inches may accumulate around and to the North and West of the City. A significant snowfall is expected inland (possible snow amounts above). A mix over Southern sections. Then a transition to heavy rain along the coast with the potential of heavy freezing rain, sleet and snow inland into Sunday morning. All areas have the chance to go back to snow during the day Sunday, but an accumulating heavy snow is unlikely at the end of the storm. This continues to be a fluid situation. JMW continues to monitor the latest information coming in.
You know where to find a no hype, no nonsense forecast.
Stay tuned.
Tonight:
Becoming mostly clear. Lows in the 20s to around 30º. Northwest winds at 5mph.
Saturday:
Morning sun will give way to thickening clouds. Snow will move in during the afternoon or evening. A mix is possible over Southern areas. Highs in the mid 30s. Northeast to East winds at 8-12mph.
Sunday:
Heavy rain along the coast and Southern areas. Heavy freezing rain, sleet and snow inland. The heaviest precipitation will occur during the morning. The potential is there for all of the precipitation to go over to a period of light toward midday. Readings in the 20s, 30s & 40s depending on location. Temperatures will plummet to the teens and 20s later in the day. The sun will return for a portion of the afternoon.
Monday:
Partly sunny, windy and bitterly cold. Highs only in the lower teens. Wind chills near 0º.
Tuesday:
Sunny and cold. Highs in the upper 20s.
Wednesday:
Mostly cloudy and much milder. Chance of showers. Highs in the mid 40s.