Light Rain/Snow Expected Monday Night through Wednesday Morning (02 Feb 2016)
POSTED ON: Monday, February 8, 2016 12:43 PM by A.R. Davies
A series of intermittent (and relatively weak) pulses of energy will move across the Mid Atlantic region over the next 48 hour. The first pulse of energy will arrive between 1600 and 2000 EST on Monday as primarily rain showers. Overnight, the atmospheric column of air above us will cool below freezing. As a result, a transition from rain showers to snow/mix showers will likely occur. Despite the cold atmospheric temperatures aloft, the surface temperatures will remain at or above freezing overnight in Annapolis thanks to a relatively warm easterly wind. The bottom line is that 1.0-3.0” of rain/snow could fall overnight and into Tuesday morning in the Annapolis area. However, I want to emphasize that there is a lot of uncertainty regarding how much snow will actually stick or accumulate (particularly on roads and sidewalks). With the uncertainty regarding the ground/surface temperatures in Annapolis (likely at or above freezing), the most probable outcome is a slushy inch or so on roads and/or sidewalks Tuesday morning. The best chance for higher snow accumulation totals will be north of Annapolis; 2.0-3.0” of accumulating snow seems likely Monday night/Tuesday morning in Baltimore and for locations north of the City.
The next pulse of energy will arrive during the day on Tuesday with a rain/snow mix. Once again, the daytime temperatures near the surface are expected to remain above freezing south of Baltimore. This will likely hinder snow accumulation during the day on Tuesday. Perhaps an additional 1.0-2.0” of rain/snow mix could fall, amounting to a slushy half an inch or so of accumulation on untreated surfaces.
The probabilistic snowfall forecast map for the Baltimore-Washington-Annapolis metro area is below. Here is a link to a larger version.
In general, there is fairly low confidence in the forecast. The atmospheric pattern is amplified and fast moving which makes forecasting the subtle details that are important to these small pulses of energy challenging. Any small changes in the track of these individual systems could change the surface temperature by a degree or two... which could mean the difference between all rain and 3-6” of snow in Annapolis. In general, I would say there is a better chance for a "forecast bust" (i.e. receiving less snow than anticipated) in Annapolis than a "forecast boom" (more snow than anticipated). I reflected this potential in the overall snowfall
Probabilistic Snowfall forecast for Annapolis:
- 35% chance of a coating to 1.0"
- 45% chance of 1-3" with around an inch of slush on streets/sidewalks.
- 20% chance of 3-6"
Note: Based on the potential for significant accumulating snow (>4.0 inches), the National Weather Service Baltimore/Washington Forecast Office has issued a Winter Storm Warning for Anne Arundel County from 2200 EST on Monday through 0600 EST on Wednesday. Please visit the National Weather Service Baltimore/DC Office Winter Weather Page for all the updated forecast advisories and warnings.
Disclaimer: This is not an official U.S. Navy weather forecast and should not be confused with the official Navy weather forecast provided by the Fleet Weather Center in Norfolk, VA. Furthermore, the official U.S. Government forecast for the greater Annapolis area is issued by the National Weather Service Baltimore/Washington Forecast Office in Sterling, VA.
Category: General Interest