From the ABC 7 Weather team

Archive for category Severe Weather January 2015

Winter Weather Moving In Sunday Night

January 24, 2015 - 08:54 PM

One system moves out and yet another is on its heels.  An Alberta clipper is diving out of Canada and is currently over the northern Plains.  This clipper will continue it's trek southeastward and will bring snow to parts of our area by dinner time Sunday.

The National Weather Service has issued a Winter Storm Watch for northwestern parts of the ABC 7 viewing area from 9 PM Sunday through 9 PM Monday.  A winter storm watch is issued when 5", or more, of snow is possible.

Clouds will increase Sunday with a rain/snow mix beginning around dinner-time (6 PM) in our far northwestern zones.  As temperatures fall, precipitation will transition to all snow after midnight.  Snow will fill in across the rest of the area overnight Sunday.  Here's our in house computer simulation at 7 AM Monday.  Blue=snow.  Pink=mix. Green=rain.

Snow showers will greet you Monday morning with school closings and delays likely.  Good Morning Washington will begin at 4 AM Monday and will have all of that information. 

Temperatures will stay in the lower 30s Monday with light snow showers continuing throughout the day.  There is still inconsistency within the models, but at this time, I think our StormWatch 7 futurecast model has a good handle on preliminary snowfall totals.

The clipper will transition to a strong coastal storm and will be a major snow storm over the Northeast.  Strong NE winds will kick up Monday with the deepening area of low pressure.  That means some blowing snow showers Monday, which could result in reduced visibility.  Check out the 988 mb low, forecast by the GFS model, by 8 PM Monday.

WeatherBell Computer Models - 18z GFS

It's still uncertain the exact track of the low, which will have an impact on snowfall accumulations in the area.  You'll want to stay with the StormWatch7 weather team throughout the day Sunday for additional weather updates, as new information becomes available. 

Regardless, expect a snowy Monday morning commute with delays and closings likely. 

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A Series of Storms Headed Towards Us For the Weekend-Latest Details

January 23, 2015 - 12:43 PM

Well here we go! A storm system that continues to approach us out of the southwest arrives this evening and will end by Saturday afternoon. A winter weather advisory (purple) is in effect this evening through tomorrow with the exception of Stafford, Spotsylvania, King George and the majority of Southern Maryland and a Winter Storm Warning is in effect for Winchester, VA, Morgan and Berkeley Counties in West Virginia and Washington County, MD.


If your commute takes you to the southwest of the region tonight, you may want to try to scoot out a little on the early side given Friday traffic …and with added precipitation , we all know too well what kind of headaches that can cause. I wouldn’t be surprised if any sporting events (basketball, wrestling matches, etc) at area high schools are canceled given the going forecast, so please be prepared for that.


We are looking at mainly rain to start as it moves in from the southwest to the northeast. There will be some snow mixed in and some pockets of wintry mix across the region as well. However, temperatures will still be relatively warm as the precipitation moves in. We will need to keep a constant eye on temperatures because of course, that will determine the type of precipitation as we move forward during the evening and late evening hours.


Caption: Surface temperatures around 7 p.m. Friday evening. Notice all temperatures around the region are above freezing.

Rain showers, moderate to heavy at times, around D.C and areas south will continue through the overnight with snow and a mix to the north and west – that’s again where we can find the heaviest accumulation of snow.


By the time daybreak comes around, we could see a changeover to snow for D.C. and areas north as temperatures drop to the lower 30s. There could be some sleet mixed in as well.

When it’s all said and done we anticipate a trace to perhaps a slushy inch around the D.C. metro area with a few inches possible north and west of town.

I do believe travel will be impacted overnight into the first half of Saturday. Again, if your commute takes you anywhere north and west of D.C., that is where we are going to find the highest amounts of snow.

All precipitation should be out of here as we go through the early afternoon hours on Saturday. Winds will pick up and we may even see some clearing as we continue into Saturday night. However, that will not last long. Our next system will be knocking on our door Sunday night into Monday morning.

Caption: Sunday evening through Monday morning could see some rain change to snow with some snow accumulation on the ground by early Monday morning.


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Storm headed towards Washington D.C. right in time for the weekend

January 22, 2015 - 01:04 PM

Welcome to winter. Finally it has arrived and finally we have something to talk about. A conveyor belt of systems are moving this way from different directions. Let’s take one at a time and first concentrate on the one Friday night into Saturday (the next after that will be Sunday night into Monday).

Most of the day Friday will turn out just fine. With a chilly start in store for Friday morning, we will start off with sunshine before clouds increase through the day. Temperatures on Friday will top out in the lower to mid 40s. While we are experiencing this in the D.C. region, a storm is getting organized moving through the deep South.

Thursday, a developing system moving out of the four-corners area and into the southern Plains is bringing lots of rain to Texas and eventually the deep South. On Friday, an area of low pressure will form along the northern portion of the Gulf of Mexico, eventually traveling north and east headed towards the Mid Atlantic.


 Above Image Credit (Blacksburg NWS)


Caption: Rain through the Deep South will eventually spawn a low off the VA coast as it moves towards the Mid Atlantic Friday.

As this low travels to the Mid Atlantic, it will eventually transfer its energy off the coast of Virginia Beach Saturday morning. In addition to that, there is a weak area of high pressure across the Mid Atlantic as well; therefore, we will have a feed of some relatively cold air filtering into the region but not arctic air and not a lot of it.


As this low travels to the Mid Atlantic, it will eventually transfer its energy off the coast of Virginia Beach Saturday morning. In addition to that, there is a weak area of high pressure across the Mid Atlantic as well; therefore, we will have a feed of relatively cold air filtering into the region but not arctic air.

ZZZZZCaption: Area of low pressure off the coast of Virginia Saturday morning.

With all that being said, we can expect precipitation to move into the region late Friday evening moving from the Southwest to the North and East and moving out by Saturday afternoon. There are still some inconsistencies in models but the spread is decreasing with each run. We are still concerned about timing, track and the depth of cold air across the region.

It does look like we could see a mixed bag of precipitation ranging from snow, rain, freezing rain and sleet. We are not talking about big totals, but we are talking about enough precipitation to disrupt traffic through the area and areas north. This storm will eventually become a nor’easter as it travels up the eastern seaboard. Any bigger snow totals would of course be north and west of D.C. with more of a rain event for areas to the south, through central Virginia and southern Maryland. There is going to be a fine line with temperatures and the type of precipitation that will fall across any area. Just know to plan ahead and keep it here! We will continue to keep you updated.

After we get through this storm, we will have to watch for another clipper type system on Sunday night into Monday. Just fasten your seat belt, it could be a bumpy ride as we continue through the 2nd half of January.

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Snow overachieves in parts of D.C. area Tuesday

January 6, 2015 - 09:46 AM


A potent Alberta clipper pushed through the region at the absolute wrong time this morning, dropping measurable snow across the D.C. Metro. Timing was about perfect as far as the modeling was concerned but snowfall totals have definitely been more than the 1 to 2 inches that was forecast. We thought there would be a few pockets of 3 inches as of yesterday evening, but some spots received up to 5 inches west of D.C. in Loudoun and Warren Counties!

The combination of the timing, the cold and more snow than expected made for a terrible commute this morning as pre treatments didn't work and plows couldn't get to work until a few inches of snow fell, leading to white roads across the area.

With the cold temperatures in the 20s and teens this morning, it appears snowfall ratios were higher than expected, so it will be good to see what the ratios were when the event is over. Snow is already beginning to taper off from west to east, with the back edge moving into the Metro as of 10am.

Live Super Doppler Radar as of 10am

Patches of flurries and light snow showers will be possible through the early afternoon but additional accumulating snow west of D.C. doesn't appear likely.

Here is a preliminary snowfall total list from the National Weather Service in Sterling, VA. The highest are listed below. Please tweet me @alexliggitt your snow totals and any pictures you would like to see on air.

Front Royal, VA: 5.3"

Middleburg, VA: 5"

Aldie, VA: 4"

Reston, VA: 3.1"


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