Rutgers Gardens could potentially reach its lowest temperature of 2020 (so far) with two models (the RAP and the NAM) simulating temperatures between 16F and 18F overnight into 1/21/20. The GFS is a warm outlier with temperatures hovering around 22F and more cloud cover than the other models, but given IR imagery and current observed cloud cover I tend to believe the higher resolution models, which indicate almost no cloud cover. Thusly, expect a low of 16F-18F (-5F to -3F) with a light NW wind below 5 mph. Winds remain light as the sun rises at 12:15 UTC and temperatures will climb past 25F by 14 UTC and into the 30s by early afternoon. With mostly clear skies during peak solar angle expect the temperature to be slightly higher than today’s high of 33F. I would expect a high temperature of 34-35F (-5F to -4F) at 19 UTC with a very light NW wind.
Average high: 39F
Average low: 21F
The dewpoint will slowly rise from 10F to 15F over the course of the day, rising near 20F overnight into 1/22/20. Over the course of the next few days expect higher moisture returns as the airmass overhead changes character and warmer temperatures arrive. High pressure moves directly overhead New Jersey during the middle of the day on 1/21 which will guarantee clear skies and no precipitation. Chance of precipitation is less than 1% throughout the day.
Monday 1/20/20: High of 33F and Low of 21F. (-3F actual vs -5F predicted)
A look at the next four days at Rutgers Gardens:
Tuesday 1/21/20: High of 35F and Low of 17F. (-4F)
Wednesday 1/22/20: High of 38F and Low of 23F. (+0.5F)
Thursday 1/23/20: High of 43 and Low of 26F. (+4F)
Friday 1/24/20: High of 44F and Low of 32F. (+7F)
Looking at the big picture for the next five days: anomalously warm conditions are likely to occur over much of Canada, the Western United States, the Great Lakes Region, and much of the Northeast, with unseasonably cool temperatures across the southeast during the next five days.
High pressure remains an inhibiting factor for precipitation in the northeast through Friday, when higher temperatures and increased moisture will begin to infiltrate the region as a result of an area of low pressure and upper level trough over the Ohio Valley. As the surface cyclone tracks along Ohio River, providing snow to northern Illinois, Indiana, and Ohio, it will bring precipitation to much of the Ohio River Valley on Friday into Saturday morning. At the surface, an area of low pressure will cross Virginia and Delaware and track into the Atlantic Ocean just south of New Jersey, providing parts of Northern New Jersey (NNJ) with the chance for wintry precipitation. The GFS is indicating a precipitation event with up to 1″ of QPF and up to 20″ of snow over interior New England. The 18 UTC GFS hints at the potential for a strong gradient of snowfall along the I-95 corridor, especially over New Jersey.
These snowfall totals are highly sensitive to the track of the surface cyclone, which will guide the thermal gradients along the coast. North of the track of the surface low there will be significant amounts of rain and sleet mixing in, limiting snowfall. Given the first snowflakes would fall 108 hours in, expect changes in the strength and track of this surface cyclone, especially with the potential for convection to be associated with this storm as a front associated with it interacts with moisture in the Gulf of Mexico.
As of right now, the timing for this storm would be early morning on Saturday 1/25/20 and if this holds, thankfully impacts would be minimal compared to this storm impacting the northeast on Friday during rush hour. However, a shift in storm evolution of 12 hours is certainly possible. Using the GEFS ensembles, the consensus is clear for a surface cyclone to cross anywhere from NNJ to the Delaware Bay early morning Saturday. The average location in the GEFS is right over Delaware Bay, which would favor mostly rain along the I-95 corridor and likely a healthy amount of snow north of I-80 in New Jersey.
Expect updates on this potential snowstorm over the next few days.