Weather Update - Sunday 11:30 PM

There weren't any drastic changes in the latest data to make me change my mind about the current forecast. I'm still expecting this storm to track close enough to us to give us a chance for a mix of heavy wet snow and a little rain. Surface temperatures will remain above freezing during the entire event, so that will eat away at our accumulation potential. Also, if temps remain above 35, then this will be mainly a rain event.



I still think it's too early to start giving a specific forecast for snow totals, but I still think the greatest accumulation potential will remain south of our area.

Flurries Possible This Afternoon

There is *just* enough instability in the air to support isolated sprinkles and flurries across the area. Luckily temperatures are in the mid and upper 40s, so all flakes will melt on impact. I expect skies to quickly clear after sunset.

Weather Update 7:30 AM Sunday

The picture is becoming clearer as this storm approaches our area. As I've said from the start, surface temperatures will be key to the forecast. Right now it looks like temps will hover just above the freezing mark as the system passes Tuesday night into early Wednesday. This will eat away at our accumulation potential. In fact, history has proven (i.e. last Wednesday night) that when surface temperatures climb to 35 or 36 degrees, we will see snow change to rain. This is a very fine line that we have to forecast and is the reason why I'm going to hold off until later this evening to speculate possible snow totals in our area.



March snow storms are actually more common than you would think. Here is a list of a few I found at the following link:

http://www.erh.noaa.gov/er/akq/climate/RIC_Climate_Records.pdf

Looking Even Further Back

Here are the maps from last year's big snow on March 1st and 2nd where the metro received roughly 6 to 10" of snow- this will help to put things in perspective. Notice the rigorous upper low in the south (moisture source and lift) merging forces with the trough to the north (which provided the cold air). This system started as rain, then switched to heavy snow. You can find these maps at the folowing link:

http://www.hpc.ncep.noaa.gov/dailywxmap/

A Look Back At Previous Storms

As another potentially massive snow storm threatens the Mid-Atlantic, I think now is a good time to look back on our two previous storms and see what kind of tracks they took. Here are the upper air and surface maps for our January 29th storm which blanketed our area with a powdery snow.





Now here are the maps from February 5th and 6th, where a storm brought a mix of wet snow and heavy rain early on, then heavy snow at the end.

Windy Friday!

Winds overnight in Central Virginia remained a bit gusty in the 20-30 mph while a strong Nor'easter continues to spin over Connecticut. The low will drift a little west over northern New Jersey today, keeping a strong flow from the west and northwest over Virginia. While the low remains in our vicinity today, there may be snow showers in primarily northern Virginia and the Northern Neck, but with surface temperatures climbing into the 40's today, it will be too warm for any of that snow to stick around. This storm will gradually weaken this weekend, relaxing the tight pressure gradient over the Northeast and Mid-Atlantic.