From the ABC 7 Weather team

Archive for February 2012

Presidents' Day weekend can bring big D.C. snows

February 16, 2013 - 05:18 AM
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Presidents' Day weekend is a time for many folks to relax for a three-day weekend and escape town. However, it's also a notorious time climatologically for big time East Coast snowstorms. Two particular winter storms on this holiday weekend helped smash snow records in the nation's capital.

One such storm occurred on February 18-19, 1979. Coined "The President's Day Storm:, this was a southern-tracking storm brought heavy snow to the Nation’s Capital.

sfcmap1979

Farmers that had already brought in equipment such as huge tractors to protest higher agriculture prices assisted with cleanup efforts following the storm. Both days of the storm set snowfall records. in Washington, D.C., and Baltimore.

February 18-19, 1979 Daily Snowfall Records Established
Reagan National: (Day 1: 14.7 inches) (Day 2: 14.0 inches)
Dulles Int’l: (Day 1: 2.5 inches) (Day 2: 13.8 inches)
BWI Marshal: (Day 2: 16.4 inches)

This storm was the worst to strike the District in more than 50 years. Totals ranged up to 20 inches in northern Virginia and Maryland with snowfall rates of 2 to 3 inches per hour. Food for thought... one hour in that storm produced more snow than the seasonal total so far this winter at Reagan National, which is 1.5 inches!). Temperatures hovered in the single digits and teens with four deaths reported in Virginia and 18 deaths from people falling on ice.

This wasn’t the only winter storm on memory for this particular weekend. The Presidents' Day weekend in 2003 featured a southern storm that began in Oklahoma and made its track to the North Carolina Coast.

sfcmap

By the time the snow ended on President’s Day (February 17, 2003), Reagan National was blasted with 26.8 inches, BWI Marshal accumulated 26.8 inches while Dulles had 21.7 inches. Schools already off on Monday enjoyed the rest of the week off for snow removal.

heavysnow

Car buried in snow near College Park, Md., after the Presidents' Day Blizzard of 2003. Photo courtesy of Andy Weiss.

To recap, two of the top 10 3-day snowfalls in Washington occurred on Presidents' Day weekend in the past.

airportstopsnows

While a slushy inch could fall early this weekend, snowfall the last few years in Washington has been scarce on Presidents' Day weekend.

Past Presidents' Day weekend weather in Washington (dating back to 2008):

February 18-20, 2012: Light rain with a Trace of snow.

Feburary 19-21, 2011: A bit of rain changing to snow with 0.2 inch at Reagan National Airport on President's day itself.

February 13-15, 2010: Chilly with 0.1 inch of snow on President's Day itself.

February 14-16, 2009: Seasonal temperatures with a Trace of rain.

February 16-18, 2008: Warm with rain. Highs ranged from 47-74 degrees with almost one-quarter inch of rain.

 

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Dual-Pol in the mid-Atlantic; What the heck is that?

March 1, 2012 - 05:10 PM
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A Special Gust Blog by Greg Schoor

Radar Program Leader-NWS Baltimore-Washington

A major upgrade is being installed in all National Weather Service (NWS) radars across the nation. Dual-Polarization technology basically takes each sweep of the radar from 2-D, to 3-D. Before Dual-Pol, a radar beam was transmitted only in the horizontal plane, so the beam could only receive data about falling precipitation in one direction. With February’s upgrade to our local NWS radar, forecasters can now get information about precipitation not only in the horizontal but in the vertical as well, telling us much more about what we are looking at. Dual-Pol is a vital part of the Weather-Ready Nation effort by the NWS. Creating a Weather-Ready Nation requires providing the media, government and other key partners with the most accurate warnings and forecasts to protect lives and property.

What are the functions of Dual-Pol data compared to the conventional radar data?

Conventional radar products only allow forecasters to see the “brightness” of clouds and precipitation (raindrops, hail, snowflakes, etc.). The larger the raindrop or hailstone, the “shinier” it will appear to the radar. On a radar screen, the most reflective objects correspond to the more intense colors on the color wheel, red, pink, bright purple. Conversely, light precipitation will have the less alarming colors, light greens and blues, maybe even gray for the lightest drizzle or flurries.

The image below shows the difference between a beam that a conventional radar would emit, compared to one that is equipped with Dual-Polarization technology. Conventional radar beams only emit a frequency in the horizontal plane, while a dual-polarized beam sends and receives information in both the horizontal and vertical planes – creating a 3-dimensional view. The two images on the right show this in terms of individual precipitation forms, a snowflake, hailstone, and raindrop.

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And The Bronze Medal For Warmest Winter Goes To...

March 1, 2012 - 05:00 AM
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With all the mild days we've had this winter, we've been discussing the possibility of breaking winter temperature records. Now meteorological winter is over and the results are in.  This winter will go on record as the 3rd warmest.

Winter in D.C. averages 38°.  This year winter ended with an average of 43.4°, beating 2002's average of 43.2° (just barely!).  So, were we anywhere close to getting the silver or gold medal?  Not really.  The second warmest winter in D.C. was back in 1890 with an average temperature of 44.3°.  The all time warmest winter on record was set back in 1932 with an average of 44.6°.

 

 Here are a few highlights from this winter:

- 70 days, out all 91 days this winter, were above average.  That's about 75%!
- Out of these 91 winter days, 18 were 60° or higher. 
- The highest temperature this winter was set on Feb. 1st with a high of 72°. 
- The highest temperature in January was 68° (Jan. 7th) and in December the highest temperature was 63° (Dec. 15th).
- The lowest temperature recorded all winter was 17° (Jan. 4th).

 

 
So, if you were wondering, after all of those mild winter days, if we would break any records, well you can now tell your friends that this was, indeed, a record breaking winter. D.C. has taken over the bronze medal! Now let's see what spring and summer bring.

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Severe weather through the Midwest and Tennessee Valley

February 29, 2012 - 03:23 PM
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A very potent area of low pressure and associated cold front have been moving east over the past few days which has made few numerous bouts of severe weather. Numerous tornadoes produced heavy damage across portions of Illinois, Missouri and Kentucky. This included a possible EF-4 tornado with winds up to 170mph that went through the town of Harrisburg, Illinois. Unfortunately, these storms not only caused many injuries but also a number of fatalities as well.

Storm Prediction Center Outlook for 2/29/12

The storm threat for the day has been primarily over Tennessee and Kentucky. Above is a look at the SPC's Severe Weather Outlook product which can also be found here with real-time updates. Notice how the yellow area dips to the south of the D.C. area. This is because of a warm front draped across our area keeping D.C. and its suburbs cooler and limiting instability. Even when the remnants of the storms get to the D.C. area from Kentucky they should weaken as they enter our more stable atmosphere.

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A look ahead to March, by the numbers

February 29, 2012 - 04:15 AM
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March can be a very active month through the D.C. area with everything from thunderstorms to snow storms possible. The month averages 1.3 inches of snow and 3.43 inches of precipitation. The difference between the record high and record low is 89 degrees which is only behind December and January, so variability is common. Just in the past 5 years temperatures have been recorded in the lower 80s as well as the teens. Here's a look at the month as a whole including the averages, extremes, past 5 years and a look to the March we have ahead of us.

Monthly Averages:

1st - High: 51      Low: 34    Sunrise: 6:40am    Sunset: 6:01pm

31st - High: 61    Low: 42    Sunrise: 6:54am    Sunset: 7:31pm

 

Extremes:

Warmest Day - 93 degrees (23rd, 1907)

Coldest Day - 4 degrees (4th, 1873)

Snowiest Day - 11.5 inches (29th, 1942)

Snowiest Month - 19.3 inches (1914)

Wettest Month - 8.84 inches (1891)

Driest Month - 0.05 inches (2006)

 

There have only been 5 records in the past 10 years:

Record high 78 degrees (10th, 2006)

4.5 inches of snow (2nd, 2009)

1.79 inches of rain (16th, 2007)

1.85 inches of rain (23rd, 2005)

1.95 inches of rain (20th, 2003)

 

DCA (Reagan) Snowfall Normal vs. Extremes

Here's a look at all of March's averages, extremes and everything inbetween.

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Timelapse of a supercell thunderstorm in Kansas from May 21, 2011

February 28, 2012 - 11:24 AM
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I've come across another awesome timelapse, this time coming from Chad Cowan who runs the site ChasetheStorms.com. Below is the video of the supercell thunderstorm marching through the Plains in Kansas back on May 21, 2011. The link to the full size video is here and his vimeo account which has other videos of chases is here. As you can tell I just love timelapse weather photography, so if you ever come across any nice videos or if you have one you'd like me to share, let me know! Send me a tweet to @alexliggitt or an email at aliggitt@wjla.com.

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2 Days Left of February -- Will It Be The Warmest Winter On Record?

February 28, 2012 - 05:00 AM
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Monday brought another round of warmer than average temperatures, as highs soared into the mid 60s in some locations.  Look at the map below to see how much higher than average temperatures were yesterday.  For the last two days of February, highs will be at, or near, average.

As of yesterday, winter has an average high of 43.5°.  So what does this mean, in regard to this year's winter?  Well, the average winter, in DC, is 38.2°, so we're about 5.3° above average.  Seems like a lot of numbers here, I know, but it will all come together.  Trust me.  Here's a chart of the top three warmest winters on record.

The warmest winter on record was set in 1932 with an average high of 44.6°, which was 6.4° above average.  Second place was 6.1° above average and back in 2002, winter was 5° above average. 

Getting back to this winter, as of yesterday, DC is 5.3° above average.  If February ended yesterday, it would go on record as the third warmest winter.  But February's not over yet!  We still have two days to go.  So how is this going to affect our potential third place standing??

Well, after computing forecast highs and lows for today and tomorrow it looks fairly likely we'll at least tie for the 3rd place standing.  Now there is a chance we could beat 2002's average, but looks like we'll just have to wait and see.  Regardless, the fact that this winter could be the 3rd warmest winter on record, since 1871, is pretty impressive to me. 

Two days left... let's see what happens.

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Meteorological winter ends Wednesday; D.C. remains unscathed

February 25, 2012 - 02:29 PM
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This photo to the left pretty much describes it; the winter of 2011-2012 was a big tease for snow lovers but smooth sailing for those waiting to hear the chant of robins. It was a winter of a little snow, no major ice storms and a few rain showers. The storm track stayed either too far west or too far south to bring the D.C. region any snow.

Now that the three coldest months which define Meteorological Winter (December, January and February) are just about over, here’s the breakdown of snowfall totals at the major airports in our region.

Reagan National Airport 2.0 inches; Winter Average: 12.7 inches
Dulles International Airport 3.7 inches; Winter Average: 18.4 inches
BWI Thurgood Marshal Airport 1.8 inches; Winter Average: 17.9 inches

There is still room for some fresh powder in March! Average snowfall in March is 1.3 inches at Reagan National. However, the snowiest March on record in the District dates way back to 1914 when 19.3 inches accumulated. The driest March is in much more recent time; 0.05 inches of precipitation accumulated in 2006.

This year’s winter seasonal snowfall just follows the trend of the last five years (minus the 2009-2010 winter with the back to back blizzards in February and one in December) in the Nation's Capital.

2010-2011 Winter: 10.1 inches
2009-2010 Winter: 56.1 inches
2008-2009 Winter: 7.5 inches
2007-2008 Winter: 4.9 inches
2006-2007 Winter: 9.5 inches

This winter wasn't just a far cry from average in the D.C. region but even the typical snowy areas in the Shenandoah Valley and farther west along the Allegheny Ridge didn't get much of the white stuff. Hagerstown, Md., has only seen 9.4 inches while Frostburg, Md., only had half of its seasonal average of 40 to 60 inches.

mdsnow

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Today's severe weather and high winds

February 24, 2012 - 12:48 PM
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5:23pm: Check out this awesome picture sent to me by Twitter User @tPFmariah9999 If you have any pictures please send them into our Weather App or Tweet them to me @alexliggitt

Beautiful picture of a rainbow in Fairfax, VA

4:34pm: Check out the position of the warm front earlier today just to the south which kept D.C. around 50 degrees while areas south of it reached 80 degrees!

4:04pm: Storm reports so far from the Storm Prediction Center.

Storm Reports through 4pm Friday

3:55pm: Storms are now beginning to exit the D.C. area with a few showers lingering across the region. Winds will be the next step but probably won't ramp up across the D.C. Metro until closer to 6pm. So far, the highest wind gusts are being seen in the mountains of West Virginia up around 35mph.

3:34pm: The Tornado Watch has been cancelled everywhere west of Stafford and Spotsylvania Counties.

3:30pm: 3/4 inch hail reported in La Plata, MD in the latest storms. The real threat is through the Delmarva at this point as well as St. Mary's County where there has been some rotation in the storms currently moving through. Stay indoors the next few hours and be sure to send or tweet me any pictures you may have!

3:11pm: The Severe Thunderstorm Warning has been extended to 4pm this afternoon.

3:07pm: A severe line of storms has developed east of D.C. and will push into the Delmarva by 4 to 5pm. The highest threat west of the Bay is for Southern Calvert and St. Mary's Counties south to the Northern Neck and the Tidewater of Virginia. Gusty winds will be the primary threat in these storms but lots of lightning, heavy rain and small hail will also be possible.

2:50pm: A Severe Thunderstorm Warning is in effect for Charles, St. Mary's, Southern Prince Georges and Calvert are in this warning area. It is headed towards Upper Marlboro to Dunkirk to Prince Frederick.

2:38pm: Just realized it's 80 degrees in Richmond and 51 here at Reagan National Airport. That is one heck of a temperature gradient. As the warm front is still to the south and the storms are moving through, we think the D.C. area will stay in the 50s the rest of the day. So much for that forecast in the 70s. Also the forecast which stated no rain. Wow, not a great day to be me! This just shows how strong systems like this can change a forecast in 12 hours time!

2:27pm: Here is a look at the satellite imagery from 2-2:15ish over the D.C. area. Notice the clear skies to the south and east of town over Southern Maryland, the Northern Neck down through the Tidewater of Virginia. I think that area will have the highest chance of severe weather this afternoon. Temperatures are in the low to mid 70s in that region. You can also see clearing behind these storms moving into Loudoun and Southern Frederick Counties. Winds still won't pick up in intensity for another couple of hours.

Visible Satellite as of 2pm this afternoon

2:21pm: Severe threat over the next hour or two for Southern Maryland as a strong storm moves into Charles County as of 2:21pm. Damaging winds, heavy rain and some lightning will be possible in these storms.

2:07pm: Please send any pictures straight into our Weather App or to iwitness@wjla.com. Also, if you have any reports, please send them to my twitter page @alexliggitt

1:53pm: A heavy line of showers and isolated storms will move through the D.C. area over the next hour or two. This line will stretch south across the I-95 corridor. Be sure to check our Live Super Doppler for the latest and I'll let you know if any warnings if they are posted.

1:33pm: This hits a little close to home but just remember that it is not really severe weather season so people are not accustomed to being prepared for this so early. For instance, I just called my mother who is traveling through SC into NC (potentially the worst are for potential tornadoes) and she had no clue severe weather was even in the forecast. This is always a good time to give a call to your friends and family to give them a heads up and tell them to keep and eye to the sky.

1:28pm: Here is a large picture of how much of the east coast is under a Tornado Watch. Gives a good idea of just how potent is cold front is!

Tornado Watch (Yellow) for the east coast

1:25pm: A Tornado Watch is in effect until 8pm tonight for areas south and east of D.C.

Tornado Watch area until 8pm

12:56pm: A very strong cold front will push through the region today bringing gusty winds and the chance for a few thunderstorms as well. The Storm Prediction Center in Norman, OK issues all of the Severe T-Storm and Tornado Watches and may place parts of the D.C. area under a Tornado Watch soon, which means conditions are favorable for possible tornadoes.

I do think this is a threat to parts of the area, particularly along the warm front south and east of town from Stafford through Southern Maryland and points south and east. The D.C. Metro and areas to the north do not have nearly the same threat as they have been socked under the clouds and temperatures are much cooler therefore limiting the instability.

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Local weatherbug sites help show gusty winds across the region

February 24, 2012 - 11:17 AM
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This photo shows a tree on a vehicle in Arlington after severe winds.

Below are some weather widgets I have put together from our partners over at WeatherBug. These will update every minute or so with the latest winds and directions. You can also click on the widget to go to the weatherbug site and check out a few of their cameras we often use.

As of Noon today, we are still under a east to northeasterly flow through much of the D.C. area as the warm front is still located to our south. The cold front is sweeping in from the west and a few thunderstorms have developed along it. This is expected to push through during the early afternoon hours. After it moves through, the winds will pick up in a major way, which is why there is a Wind Advisory in the Metro and a High Wind Warning west. Winds may gust up to 60mph at times. You can also check this map for a look at the latest gusts.

Here is the Richard Montgomery HS weatherbug site in Montgomery County, MD.

Your weather just got better.

Here is the Earth and Space Science Center in Frederick, MD.

Your weather just got better.

Here is the Gainesboro ES in Winchester, VA.

Your weather just got better.

 

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High Wind and Fire Weather Watches (Video Update)

February 23, 2012 - 02:23 PM
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The latest development with this strong cold front is that a High Wind Watch (brownish color) has been issued along and west of the Blue Ridge. By tomorrow around Noon, the cold front is expected to push through the D.C. area, bringing with it wind gusts up to 50 and possibly 60 m.p.h. This is a very strong frontal passage that will bring much cooler air for the weekend but very little in the way of precipitation. With the warm temperatures, gusty winds, and low fuel moistures, a Fire Weather Watch has also been issued.

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A Fire Weather Watch has been issued for the D.C. Area

February 23, 2012 - 11:08 AM
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It isn't often the D.C. area is put under a Fire Weather Watch. It probably happens about 2 to 3 times per year. It is issued when conditions are expected to be favorable for the spread of wildfires in the next 12 to 72 hours. It usually precedes a Red Flag Warning which means that extreme fire conditions are possible due to not only the current weather but also the weather that has been around the region the previous week or two. As Reagan National Airport has only received 0.58 inches of precipitation in February that makes it nearly an inch and a half below normal for the month.

Fire Weather Watch Map

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So Today Marks How Many 60+ Degree Days This Winter??

February 23, 2012 - 06:00 AM
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People driving around town with their windows open, dining outdoors, walking around with only a light jacket, or even no jacket at all, pretty much sums up the majority of our winter, to this point. 

Highs will be well above average, once again today, as we soar into the 60s.  In fact, I wouldn't be surprised if a few spots made it to 70°.  Would that break any records?  Most likely not, with 78° the current daily record for D.C.  Even though we may not break a record, just over 3/4 of winter (meteorological winter: December 1 through the last day in February), has been above average.  Yep, that's right.  64 out of the 84 days of meteorological winter have been above average.  Here's a look at how much warmer temperatures were yesterday compared to average. 

Departure From Average On Wednesday

Temperature departures were about 15° warmer than average!  Average highs in winter range from 44-52°.  Today and tomorrow, though, we'll reach the 60s!  So how many times have we climbed to the 60° mark or higher?  16 days of the 84 days this winter have been 60° or warmer.  Talk about a mild winter season!  Now these numbers are from yesterday.  I didn't include today and tomorrow, since nothing's official. 

The milder weather tends to get more people outdoors and also helps on the heating bill.  It also can also bring a few "winter flowers".  Take a look at the pollen count for late February.  Seems hard to believe trees are high this time of year. 

Enjoy the mild temperatues while they're around.  "Colder" air is moving in for the weekend -- and when I say colder, I mean, temperatures will be right around average.  Go figure!  Looks like we'll just have to wait and see if all of the above average temperatures will equal a "warmest winter on record".   

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Yosemite National Park in HD (Timelapse Video)

February 22, 2012 - 04:30 AM
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(Photo: projectyose.com)

Have you ever been to Yosemite National Park? I haven't. That's why I always check the web for videos such as the one below. There is nothing I love more than timelapses of awesome scenery and weather. It's always an added bonus when it is from the United States!

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Dust storm big enough to be seen from space over Texas (Video)

February 21, 2012 - 11:07 AM
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This isn't something the D.C. area has to worry about in the near future... Parts of the Panhandle of Texas had to deal with a powerful dust storm yesterday. It caused numerous accidents, near zero visibility, and even 2 deaths. This was all caused by very strong winds behind a cold front which picked up the dust and dirt. Around Noon yesterday, winds were out of the west sustained at 46 m.p.h. gusting to 56 m.p.h. Winds gusted to at least 48 m.p.h. for over 2 and a half hours. There's a pretty neat looking video and package here from the NBC Nightly News yesterday. Check out this picture from space as well from yesterday afternoon.

MODIS image of the dust storm from space

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Weekend snowfall totals, maps, and video

February 20, 2012 - 12:04 PM
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What a bummer of a weekend for the D.C. snow lovers as Central and Southwestern Virginia getting the brunt of the storm. Snowfall totals up to 9 inches fell over parts of SW Virginia and Southern West Virginia this weekend. The highest totals were 9.8 inches in Alleghany County, Virginia and 9.6 inches in Montgomery County, Virginia which is near Blacksburg. Locally, only an inch or two of snow fell in Southern Maryland and closer to D.C. but up to 6 inches or more fell in areas such as Orange County, VA and south towards Charlottesville and in the mountains along I-64. Here's a look at how much snow fell from the National Snow Analysis page.

Estimated Snowfall Depth (NOAA/NOHRSC)

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Sunday Snow - The Latest Saturday Afternoon

February 18, 2012 - 02:43 PM
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Boy have we been watching this possible Sunday snow for some time.  Hard to believe here on Saturday afternoon with the temperature near 60° that snow by this time tomorrow is even possible.  Here is where the storm is right now.

 

ZZZZZ

 

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Heavy snow not likely for Sunday

February 17, 2012 - 02:47 PM
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Another day has gone by and it still appears that a storm will affect the east coast on Sunday. There are still numerous questions as to the strength and exact track this system will take but here are some of my thoughts as of Friday afternoon.

The D.C. Metro area shouldn’t expect a heavy snow storm. I say this for many reasons which I am more than happy to outline. The first and primary reason is the storm is a fast mover and will move off the east coast and into the ocean rather quickly. This will only allow for a couple of hours of precipitation. Precipitation amounts also appear like they will be light with only a quarter to a half of an inch of liquid. If this is the case, which is not set in stone, if it all falls as snow, then a 10:1 snow ratio would only give 2.5 to 5 inches maximum. Not a big storm.

Further delving into the reality that a heavy snow storm is unlikely, the forecast track of the low is unfavorable for heavy snow as it does not intensify and curve up the coast towards the northeast. Usually when that happens it brings heavier snowfall for a longer duration. Finally there is the whole question about the models. Each does show a storm developing in Texas, moving along the Gulf and eventually off the east coast. A number have now been trending farther to the south with some even showing no precipitation at all for the D.C. area.

Sunday evening forecast of 6 hour precip and MSLP

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Snow on Sunday in D.C.

February 17, 2012 - 08:48 AM
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Adam Caskey's 'snow excitement factor' has steadily increased throughout the week. (Photo: ABC7)

Follow me on Facebook and Twitter for additional information.

• Snow Chance: Likely
• Time: Sunday
• Forecast Confidence: Average to Below Average
• Snow Excitement Factor: 3 out of 10
• Snow Amount: TBD (read below for possibilities)

It’s now fair to say that snow is likely on Sunday, but what remains a mystery is the amount of snow that will fall upon Washington.

Model guidance is still in some disagreement on the exact track of the storm and certain interactions in our atmosphere, which will be critical in determining snow totals. I’ll break it down for you in simple terms regarding the computer models and odds in terms of snow totals.

This will be a coastal storm, which is the type of storm that generates the highest snowfall in the Washington area, however, Doug Hill stated an important point this morning, “…this will NOT be another Snowmageddon.” It’s also important to note that we’re trying to predict the outcome of a storm that has yet to develop, nevertheless, I can provide preliminary odds of snow amounts.

As of now, I think this will be a low to moderate impact storm system for Washington, and I’m currently leaning towards “low impact.”

 

 

 

Before jumping into some of my rationale, above is a graphic indicating the odds of getting various accumulations in the D.C. metro area. I do think a trace to 2 inches is likely (60 percent) with 3 to 6 inches possible but unlikely (30 percent) and more than 6 inches highly unlikely but possible (10 percent).

It’s more than just figuring out how much moisture will be squeezed out of the clouds and how that translates into snowfall. Other factors such as surface/ground & road temperatures, phase changes, crystal composition, timing, intensity and more needs to be determined.

 

 

Model guidance has yet to be very reliable this winter, and this situation is no exception, which is why my confidence is “average to below average” but rising. The projected tracks of various models are shown in the graphic below and while it may look like they’re pretty close, in fact, the disparity is significant in terms of the overall effect on our region.

Basically, fellow snow lovers need to hope for the most northerly track (white - NAM), and snow haters need to pull for the southerly track (DARK BLUE – NAVY). Neither of which are guaranteed, of course.

 

 


As much as I’d love to, I can’t buy into the northerly & very snowy track as I’ve notice poor performance and great inconsistencies in this model beyond 18 hours all winter, and the most southerly track is a bit of an outlier. In turn, a blend seems in order as is the case is many situations. However, I have more confidence in the yellow track (CMC) as it has shown more consistency over the past few days.

 

 

In regards to precipitation type, I do think it will mainly be snow in the D.C. area with a rain to snow transition likely south of D.C. However, I must go back to persistence like in my previous posts and note that model guidance has had a tough time nailing precipitation type all winter.

Nonetheless, should we see rain, it would be brief in the metro area with a quick changeover to snow. This is just a basic assessment, and remember that we will have updates all day and through the weekend here on wjla.com.

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StormWatch7 Mobile App Is Here!

February 16, 2012 - 03:01 PM
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We have the largest team of broadcast meteorologists in Washington and, with our new mobile app, we can be with you all the time.  Many of the features of this new app are unique to us.  Here's a quick demo:

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