Wednesday, March 3, 2010
Mar 3: Storm Bust, Next Week Warmth
Today's Forecast Bust: Storm Was Too Warm, Too Dry
While before yesterday, my forecasts for this storm called for near or less than an inch of snow, the consistency of so many models trending wetter for the area convinced me that the storm would in fact take that direction, with more snow falling in the area. Yet it turned out that this last minute trend was incorrect on the models, as the storm took an unexpected direction by tracking closer to the coast and bringing warmer temperatures, bringing rain to southern New Jersey instead of 1-3 or 2-4 inches of snow. There was also not as much precipitation as the models showed, with Central Park having reported 0.07 inch of precipitation instead of the 0.50 inch of precipitation that the GFS showed.
For the short term, expect light rain/snow to slowly taper off, with snow accumulations near or less than an inch north and west of NYC. Scattered rain/snow showers are still possible through the afternoon and early evening hours.
Is Winter Over?
I am currently thinking that once the mild spell ends during mid-late next week, the cold temperatures (but not as cold as they were) would briefly return, with the time frame for another chance of snow possibly between March 10 and 20. However, if any snowstorm does take place in this time frame, unless we get very cold air to enter the Northeast United States, that would only be a generally light snowstorm. After this time period, the chances for snow become increasingly unlikely, as the sun angle is very high, the average temperatures are already past 50 degrees, the cold spells become much weaker and the average storm track shifts further north.
It is still impossible to rule out any cold and snow until at least early April though, as despite it being unlikely, it has happened before. Examples include the early April 2007 cold blast, where temperatures were well below average, and accumulating snow was even reported in places such as southern Virginia and North Carolina.
Weekend Warm-Up, High Temperatures In The 50s By Monday
As I previously mentioned, the temperatures are about to turn warmer. While the low temperatures should still be chilly through Saturday, generally in the 20s across the area, they should also start to become warmer afterwards. High temperatures should steadily rise through the late week and weekend, already peaking near 50 degrees in parts of the area by Sunday. Monday should be the warmest day, with high temperatures in the lower 50s across a rather widespread part of the area.
There is still uncertainty for the storm in the middle of next week, however the 06z GFS run showed an interesting solution that also can't be ruled out considering the uncertainty. It shows a storm forming in the Plains and instead of going northeast towards the Great Lakes, it is blocked from doing so and starts to move east. As the storm is blocked from moving north, the warm air is also blocked from moving into the area, and as a result the GFS keeps the cold air. By the time it reaches the Ohio Valley, as many other storms have done this winter, it transfers its energy to a secondary low, that moves offshore.
At this time, I would say that some rain is possible in the middle of next week with above average temperatures, though if the GFS does verify and the storm is blocked from going too far north, there might be snow in the Northeast and as far south as southern New York.
Posted by NYC Weather at 7:58 AM