Mar 19, 2011: Spring Starts With 2 Snow Potentials

***This post is from 2011. Please visit the MAIN PAGE to see the latest forecasts for the NYC area.

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Note: The 5-Day Forecast was not updated tonight, however it will likely be updated on Sunday morning. In addition, a Light Snow Alert will likely be issued for Sussex and Orange counties for accumulating snow and sleet on Monday morning.

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As a cold front moved through overnight, temperatures steadily dropped across the area, and today's temperatures were nowhere near as warm as yesterday's temperatures, staying steady in the mid 40s to lower 50s in the afternoon with the warmest temperatures of the day observed around midnight.

Spring officially starts tomorrow, however the pattern coming up suggests otherwise, with tomorrow starting a more winter-like pattern that may last through early April. Not only will this pattern bring colder than average temperatures, but for this coming week, we are looking at not one, but two storms that will bring snow to parts of the area.


Tomorrow's Outlook:

After cold temperatures tonight, which will drop into the upper 10s to upper 20s away from NYC, tomorrow will bring mild temperatures to the western parts of the area but chilly temperatures further east. With sunny skies and an ESE wind expected, high temperatures will peak in the lower to potentially mid 50s from NYC and further west, and in the mid to upper 40s for the eastern parts of the area except for the immediate coast which should stay in the lower to mid 40s.


Monday: Morning Snow, Sleet For Interior Areas

A storm expected to move through the Northeast on Monday will push the cold air mass out of the region, but not before bringing front end frozen precipitation for the Northeast and even into the area. The latest models continue to suggest that 850 and 925 mb temperatures will be below freezing as the storm moves in, allowing for the precipitation to begin as snow as far as the immediate north/west suburbs of NYC early on Monday morning, with a start of snow and sleet also likely in interior southern Connecticut. As temperatures steadily warm up throughout the late morning, precipitation will first change over to sleet, then rain, ending by the early afternoon hours from west to east.

No snow and sleet accumulations are expected in the immediate NYC area, as any snow that falls should be wet snow that melts on contact, however especially towards Sussex and Orange counties, more snow and sleet are expected, and there is the potential for 1 to 2 inches of wet snow and sleet to accumulate. A Light Snow Alert may be issued on Sunday morning for this storm.


Wednesday - Thursday: More Significant Snow Potential North Of NYC


Monday's storm is only the first of two snow risks for this coming week. As the storm moves into Maine, it will bring a colder air mass behind it, bringing colder temperatures for Tuesday night. A storm is expected to move near Chicago on Tuesday, bringing a wide area of moderate to potentially heavy snow for the central and northern Great Lakes area, and with a high pressure to the north supplying the storm with cold air, freezing rain is a risk for the southern Great Lakes.

The main highlight of today's models for the area are the ECMWF, which show heavy snow for northern New Jersey with significant accumulations, and the DGEX, which also shows heavy snow for northern New Jersey. The GFS is the warmest model, showing mostly rain for New York City with snow further north, and the GGEM is the coldest model, keeping the heaviest snow south of New York City. Based on this data, there would be support that the moderate snow axis could move through northern NJ and the immediate NYC area, however when looking at the overall trends, since this morning the models have adjusted northward. With the cold air mass in place and high pressure to the north of the storm, it will be blocked from tracking north of NYC and would likely take an ESE track, however especially with the ensemble means of the GFS, GGEM and ECMWF still showing northern solutions, I sided with the northern scenario at this time.

Should this scenario verify, the storm will track from Chicago towards southwestern Pennsylvania and move off the coast of southern New Jersey. The best risk of accumulating snow would be north of NYC, especially towards interior southern Connecticut and Orange County, NY, during Wednesday night. Some snow would likely fall in northern NJ and NYC, especially towards the end of the storm on Thursday morning, however the main precipitation type would be rain or a mix. The highest risk of moderate snow accumulations would extend from the central/northern Great Lakes into the southern/central Northeast.


As this is still in the medium range, there is still uncertainty with the storm. The other possibility is that a colder and further south storm may verify, bringing a moderate snow potential into northern New Jersey and potentially the immediate NYC area. At this time, this is not the most likely scenario, however it needs to be watched in case it does become the expectation. Stay tuned for more information on this storm and how it may affect the area.