From the ABC 7 Weather team

May much warmer than average, hot week ahead

May 25, 2015 - 04:21 PM
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May has been an exceptionally warm month in the D.C. area, with 18 of the 24 days so far experiencing above average temperatures. There have been three 90 degree days and 15 days with high temperatures above 80 degrees. Our averages for May 25th (Memorial Day Monday) are 78 for the high and 59 for the low, so chalk up another day with highs 5 to 10 degrees above average.

Latest 7-Day Outlook here

Here are the five warmest months on record in D.C.:

1991 - 73.0F

2004 - 71.8F

1944 - 71.6F

2012 - 71.4F

1880 - 70.5F

Thus far, May 2015 is averaging 71.1F putting the month solidly as the 5th warmest. Temperatures this week are expected to consistently be in the upper 80s, which is right around 10 degrees above average. This could easily put the month as the 3rd or 4th warmest on record, but the 73F recorded in 1991 appears safe. Regardless, this will be only the 7th time since 1871 May has experienced an average temperature above 70 degrees.

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Memorial Day Weekend forecast for D.C. and the Beaches

May 21, 2015 - 03:00 PM
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Today happens to be the coolest since May 1st, the fourth time this month with below average temperatures and also as we sit in the 50s is currently 30 to 35 degrees cooler than just 48 hours ago.

These chilly temperatures and pesky showers won't hang around for the weekend though. Big changes are expected by tomorrow as sunshine filters back overhead along with milder temperatures in the upper 70s.

The weekend is looking fantastic. High pressure is expected to filter overhead on Saturday and will move off the east coast Sunday. Sunny skies are expected Saturday with seasonable temperatures in the mid 70s. As the high moves east, a southerly component to the wind will help usher in warmer air once again and highs should reach the low to mid 80s Sunday and upper 80s Memorial Day Monday.

Weekend Outlook

The Beaches

Just so you have the right mindset, water temperatures across the east coast from Virginia Beach to the Delmarva are still in the 60s, so it will be chilly at times right on the beach. South of Hatteras, water temperatures are much warmer in the 70s. I can vouch for this as I swam in the Atlantic at Sullivans Island outside of Charleston, SC last weekend. Very comfortable water there!

Beach Outlook

Right now we're still expecting plenty of sunshine both Saturday and Sunday along the eastern seaboard. Temperatures will be cool in the upper 60s to near 70 degrees each day at the northern beaches, and in the low 70s from Virginia Beach to Nags Head.

Memorial Day Monday appears like it will be a good day to hang around at the beach and head home in the afternoon. Temperatures look like they will be in the mid to upper 70s under mostly sunny skies. Enjoy it if you're going!

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First 90 degree day of the year possible Tuesday

May 11, 2015 - 01:51 PM
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The month of May is currently running nearly 8 degrees above average so far but some relief is in sight by the middle and end of the work week. Temperatures again topped the 80 degree mark today and may possibly reach 90 degrees Tuesday. The average high at Reagan National for this time of year is in the mid 70s. Here's a look at the first 90 degree days over the past five years in Washington D.C.

First 90F Day in D.C. over the past 5 years

You can see just last year, the first occurrence was May 13 when it reached 92F. Last year only had 24 days at or above 90 degrees, which is below the average of 36 days. While it still hasn't reached 90 degrees yet this year, this doesn't mean it will be a cooler summer. 2011 and 2012 featured the first 90 degree day late in the month of May and still experienced 50 and 53 days respectively at or above 90F.

Forecast temperatures Tuesday at 3pm per the 4km NAM Model (Courtesy: WeatherBell Models)

Tuesday our forecast is currently to reach 89 degrees, but with a frontal boundary moving through we may get some additional compressional heating with strong westerly winds helping push parts of the area over 90 degrees. If the region doesn't reach 90 degrees tomorrow, we'll have to wait at least another week or two for the next opportunity. At this point it appears the 18th and 19th might be rather warm ahead of a cold front.

Wednesday through Friday should be much more comfortable with temperatures in the 70s and dewpoints back in the 50s and 40s.

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Eyes on the tropics already? (Saturday Update)

May 9, 2015 - 09:15 AM
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(Update Saturday 5-9-15 9:30 PM)

Tropical Storm Ana has formed and is at its peak strength right now.   Getting the worst of it right now are the coasts of Northern South Carolina and Southern North Carolina (did I get that right :D ), or right around Wilmington, NC.

Satellite / Radar Data Saturday Night


The National Hurricane Center is only issuing a forecast through Monday at 2PM, to where it will only hold any sort of tropical characteristic up through that time.  After 2PM Monday, this storm poses little threat for anything other than ordinary thunderstorms and locally brief heavy rain.

 

NHC Official Forecast

 These two aspects, along with a cold front that also nears the region, confirms that Monday will be the day likeliest for storms in the Mid-Atlantic.  Our Futurecast forecast shows scattered showers and possible thunderstorms over the region by 11AM Monday.

Our Local Futurecast Forecast at 2PM Monday


(Previous Update from Tuesday)

 

We're still keeping a close eye on the disturbance along and east of Florida affecting the Bahamas. This system continues to have a chance for subtropical development over the next few days but as of now appears like it will have little to no affect on the D.C. area.

 

 This area of showers and storms is associated with a surface and upper-level trough, meaning it doesn't have any tropical characteristics at the moment, but may become subtropical over the next few days.

The National Hurricane Center is monitoring the area for later in the week, and as of Tuesday has a 40% chance for development. For the latest Special Tropical Weather Outlook, the NHC has stated,

A large area of disorganized showers and thunderstorms extending
from the northwestern Caribbean Sea across Cuba, southern Florida,
and the Bahamas is associated with an upper-level trough and a weak
surface trough. An area of low pressure is expected to form in
association with this disturbance during the next day or two. The
low could gradually acquire subtropical characteristics over the
next few days while it moves generally northward at a slow forward
speed. For additional information on this system, see High Seas
Forecasts issued by the National Weather Service. The next Special
Tropical Weather Outlook will be issued on this system by 11 AM EDT
Wednesday.
* Formation chance through 48 hours...low...20 percent
* Formation chance through 5 days...medium...40 percent

Find more on the difference between a tropical, subtropical and extratropical storm here.

Atlantic 5-Day Graphical Tropical Weather Outlook (Courtesy: National Hurricane Center)

As of this morning, the majority of model guidance either keeps the system offshore along the southeast coast or drifts the low into South Carolina on Friday. All guidance as of now keeps the low well south of the D.C. area, but some tropical moisture still may filter its way into the Mid Atlantic byt early next week.

We'll continue to keep a close eye on it as these types of disturbances are notoriously difficult for a global model to accurately forecast. Be sure to stay tuned, especially if you are headed to the southeast beaches within the next week.

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Daylight is dominating

May 1, 2015 - 12:53 PM
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I felt like it was only a few weeks ago when we were waking up and the sunrise was after 7am and the sunset was prior to 7pm. It has now been a solid 8 weeks since we entered daylight saving time March 8th. Sunrise that day was 7:31am and sunset was 7:08pm.

Fast forward to May 1st and the sunrise is 6:10am and sets at 8pm. That means in just 8 weeks the D.C. area has gained 2 hours and 13 minutes more daylight. March 8th featured 11 hours and 37 minutes while May 1st has 13 hours and 50 minutes.

Duration of Daylight

Through May 31st, the area will gain an additional 51 minutes to hit 14 hours and 41 minutes by the end of the month. Through June there's only another 13 minutes to gain, however, as the longest day of the year happens around the summer solstice June 21st. The longest days of the year actually extend from June 18th through the 24th.

The difference between the summer solstice and winter solstice in terms of daylight is 5 hours and 28 minutes, as by December 21st and 22nd, D.C. will be back to 9 hours and 26 minutes of daylight.

Enjoy the sunshine and warmer temperatures this weekend!

Sunrise and Sunset times below.

Sunrise and sunset times looking ahead

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Tree pollen count for D.C. may have been highest for the year

April 21, 2015 - 12:33 PM
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Meteorologists across the D.C. area receive a daily email update with the pollen count for the preceding 24 hours. Chief Microbiologist Susan Kosisky or Health Technician Mariko Shigeto Marks from the U.S. Army Centralized Allergen Extract Lab in Ft. Meade always give us a thorough update on the main offenders in the air whether it is trees, weeds, grass or mold. This time of year it is typically trees and mold. The count we received this morning was the highest so far this year for trees in the very high range.

April 20 Pollen Count


From Susan Kosisky,

"Despite the rain showers, our area tree species have put together some pretty high pollen counts. With the warm temps and breezes on Saturday, our tree count climbed to 1647 grains/cubic meter. We had a slight reprieve on Sunday, however, yesterday the trees unloaded. The yellowish-green film on the cars yesterday said it all. Our count with rising temps and breezes was 2359.11 grains/cubic meter which is VERY HIGH.

Oak pollen, which is very high, is the main contributor at 1840 grains/cubic meter. Ash, sycamore, sweet gum, pine, birch and beech are also adding to the count in a big way. This might have been the highest count we will see this tree season. Mold spores, loving the rain, also climbed considerably. Ascospores abound.

Tree pollen is VERY HIGH at 2359.11 grains/cubic meter.

Grass pollen is LOW at 1.28 grains/cubic meter.

Weed pollen is LOW at 0.64 grains/cubic meter.

 

Mold spores are in the MODERATE range (NAB range) at 11,592.65 spores/cubic meter, which is high for local area mold spore counts."

As many of you could probably tell by the color of your car, sidewalks, roadways and just about everything else outside, the tree pollen is right around its peak. It typically peaks in the 3rd or 4th week of April, so we're almost in the clear. If you're allergy prone (like yours truly) be sure to take the necessary precautions.

Our recommendations:

- Take allergy medications

- Keep your home and car windows closed

- Shower or wash your hands and face soon after exercising outdoors

- Avoid going outside for a prolonged period of time on breezy days

- Wear sunglasses for protection from pollen getting in your eyes

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Heavy rain overnight, severe storms possible Monday in D.C.

April 19, 2015 - 11:59 PM
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After a beautiful Saturday which featured our warmest temperature of the year so far at 84 degrees at Reagan National, it was much cooler Sunday. Easterly winds took over ahead of a warm front which kept highs in the 60s. Clouds were on the increase throughout Sunday approached from the southwest before finally getting to the D.C. Metro between 4pm and 7pm on Sunday evening.

Potential Rainfall Totals by Tuesday morning

Periods of rain continued overnight into Monday morning. Rain may be moderate to heavy at times with upwards of an inch possible by the time it exits the area during Monday mornings commute. A Flood Watch has been posted through Monday for the majority of the D.C. area. Winds were also breezy overnight, with gusts up to 30 mph.

Warmer air will filter into the region Monday ahead of the trailing cold front. Highs should reach the upper 70s to near 80 degrees Monday afternoon. This will elevate the instability levels across the region and the cold front will act as the lifting mechanism to create the chance for thunderstorms Monday evening. Winds aloft will be strong creating the chance for a few damaging wind gusts. This is why the Storm Prediction Center has placed the D.C. area and points south into a slight risk for severe storms.

Slight Risk for severe storms in the area shaded in yellow

The cold front will move east of the area Monday night into Tuesday morning and cooler temperatures are expected the remainder of the work week.

Be sure to check for the latest 7-Day forecast here.

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Stormy Afternoon and PM Rush

April 10, 2015 - 07:41 AM
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Don't be fooled by the cool, cloudy start today. A big change is coming.  A potent cold front that has a history of producing severe weather in the Midwest and Ohio Valley will arrive in D.C. Metro later today.  Be prepared for severe weather.  The most likely threat will be damaging winds.  

Severe Storm Impact

Hail around 1" in diameter is also possible in isolated storms along with heavy downpours. The threat of tornadoes is low.  The farther south you live, the greater your chances that storms will be strong. 

Severe Storm Risk Area

Any severe weather in D.C. would be isolated and short-lived.  Southern Maryland and Central Virginia has a 15% chance that a severe storm will come withing 25 miles of their home. The line of showers and thunderstorms should reach the I-81 corridor just after lunch time. 

Futurecast

By mid afternoon, it reaches the metro. 

Futurecast

By the late rush, it exits east of I-95 and then skies will clear out tonight.  This good news is that the severe threat is on the lower end of the scale today.  This same storm spawned a deadly tornado in Illinois last evening. Amazing video on You Tube you can watch here.  For us, be prepared to seek shelter indoors this afternoon.  Remember lightning can be deadly. Keep a close eye on conditions when the kids get home from the Bus Stop today.   The Stormwatch7 app here will help you stay informed with live radar updates and severe weather alerts on your phone. In addition, Chief Meteorologist Doug Hill will break into programming if necessary today if there are any warnings.  He starts team coverage with Steve Rudin starting at 4p on ABC7 News. Hang in there for the weekend!  It will be perfect with breezy conditions on Saturday. But sunshine and upper 60s to around 70 can be expected both days. Perfect for Cherry Blossom peak blooms!  Share your photos with me this weekend and early next week and I'll put them on the air during Good Morning, Washington! Post them on my Facebook page here or on Twitter @JacquiJeras

 

 

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Windy Saturday, Easter SUNday, Nationals Baseball is back!

April 3, 2015 - 05:46 PM
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Plenty of sunshine is expected this weekend but Easter Sunday still appears to be the better day of the two as windy conditions will prevail on Saturday.

Low pressure will continue to intensify as it moves into the Northeast tonight into Saturday morning. The resulting pressure gradient between the low and entering high pressure will make for windy northwesterly winds throughout the day. Winds may gust as high as 40 mph in the morning hours but winds should finally diminish Saturday evening. Temperatures will be cooler than Friday (which hit 71 degrees) with highs around 60 degrees.

Easter Sunday Hourly Forecast

Easter Sunday will start off rather chilly, with lows in the 30s in the outlying suburbs to near 40 degrees in town. Milder temperatures should enter by the afternoon with highs in the low to mid 60s. Winds may still be on the breezy side out of the southwest around 10-15 mph.

Nationals Baseball Forecast

Is anyone else excited for Nationals baseball? I am absolutely pumped for the season opener on Monday at 4:05pm. Weather conditions should be just about perfect for the game with temperatures in the mid to upper 60s throughout the day under partly cloudy skies.

Be sure to stay tuned to the latest forecast updates this weekend!

 

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Peduncle elongation: Washington D.C. cherry blossom peak bloom forecast

April 1, 2015 - 05:45 AM
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The peak bloom date is defined as the day in which 70% of the blossoms of the Yoshino Cherry trees are in full bloom. Obviously, this is weather dependent and can vary from year to year; however, the actual Cherry Blossom Festival dates are "set" based upon the average bloom date of April 4th. In fact, taking a look at the statistics, it appears that peak bloom has taken place in a very broad date range, occurring as early as March 15, 1990 and as late as April 18, 1958 (courtesy NPS).

While National Park Service Horticulturists issue several bloom forecasts, they clearly state that "it is nearly impossible to give an accurate forecast much more than 10 days." The forecast for this year's peak bloom is currently forecast for April 11 to April 14.

The way the National Park Service tracks the progress of the trees is by monitoring the progress of the 5 steps of growth. By monitoring these processes the horticulturist can adjust and update the bloom forecast accordingly. Here are the 5 steps and the corresponding imagery. Take a look and then you will be able to better understand the process whether you head down to the basin or not.



1. Green Color in buds 2. Florets visible 3. Extension of florets 4. Peduncle elongation 5. Puffy white - Courtesy: National Park Service

Final thought...if you cannot or do not make it down to see the Yoshino Cherry trees you are not 100% out of luck. Kwanzan cherry blossoms are provide a vibrant bloom and generally emerge two weeks later than the predominant Yoshino trees along the Tidal Basin. To catch a glimpse of these trees one need only to head over to the East Potomac Park south of the George Mason Memorial.

*Special thanks to our old friend and Meteorologist Adam Caskey for his collaboration with me on this blog.

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April weather in the D.C. area

March 31, 2015 - 06:21 AM
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April begins on Wednesday and the first day of the month is forecast to be sunny and slightly cooler than average in the mid to upper 50s. The average high for the start of the month is 62 degrees. By the time we get to April 30, the average high soars to 71 degrees. Just a couple of years ago in 2013 on April 10, the high reached 91 degrees, a record for the date.

Complete April Climate Statistics - NWS Baltimore/Washington

With that being said, 90 degree temperatures are definitely obtainable for the month. Only 7 days during the month have record highs below 90 degrees with 5 of them being the 1st through the 5th. The highest temperature last year was 85 degrees on the 13th of the month.

April Weather in D.C.

April features 12 hours and 38 minutes of daylight on the 1st of the month and 13 hours and 48 minutes by the 31st. Sunrise and sunset on the 1st is 6:53am and 7:31pm. By the 31st it rises at 6:12am and sets at 7:59pm.

Sun and Moon Data - U.S. Naval Observatory

The month still features some cold spells, with the last record low being recorded in 2007 on the 8th when the mercury dropped to 29 degrees. Measurable snow has also been recorded 15 days out of the month, with the latest on the 28th back in 1898 when 0.5" fell.

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Unprecedented Quiet Start to Tornado Season

March 24, 2015 - 05:40 AM
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Zero. None. Nada.  That's how many tornadoes have been recorded in the United States so far this March.

Preliminary Tornado Count 2015

March tends to be a busy time for severe weather forecasters, but so far not only have there been no tornadoes this month, there hasn't even been a watch issued.  According to Warning Coordination Meteorologist Greg Carbin at the Storm Prediction Center in Norman, OK where watches are issued, it is unprecedented.

Source: Storm Prediction Center

Carbin says this has never happened since the Storm Prediction Center has been keeping records dating back to 1970.  Typically there will have been dozens by this time of the year.  On average, 130 tornadoes are recorded from January through mid to late March. This year there are 28 preliminary reports from January and February combined. That's 10 percent of average.

U.S. Tornado Trends

Most severe weather this time of the year happens in the south. But, tornadoes can and have occurred in any month of the year in Virginia and Maryland. 

March Severe Weather Probabilities

Why has there been such a lack of tornadoes?  You can thank the chilly temperatures in the east for one thing.  We've had a persistent pattern that has not allowed much moisture, heat or instability from the south to clash with cooler arctic air from the north. 

On average Virginia will see 18 tornadoes a year and Maryland will experience 10.  Most of those tornadoes occur between April and September. 

Tornado Climatology by State

Will the quiet start to the season continue?  Perhaps for at least the short term. cooler than average temperatures are expected to continue in the east into early April. However, weather patterns can change quickly. April and May are typically the busiest months of the year for tornadoes. Just because it's quiet now, doesn't necessarily mean that there will be a correlation of low tornado counts through the end of June.  In fact, the Storm Prediction Center has issued a slight risk of severe storms for both Tuesday and Wednesday. 

Severe Weather Outlook Tuesday

While we're not expecting any severe storms in the D.C. region this week, we could hear a few rumbles of thunder on Thursday and there could be some gusty winds with those storms. 

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Snow showers and flurries possible overnight into Tuesday AM

March 23, 2015 - 03:06 PM
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Snow fell in parts of the Midwest this morning and will continue to move to the south and east this evening into tonight. Early tomorrow morning, the weak disturbance will move into the D.C. area bringing the chance for some light snow showers or flurries. Here's more on what you can expect.

The system is currently moving out of Indiana and into the Ohio Valley. Areas such as Chicago picked up 1 to 5 inches of snow but the disturbance will continue to move into areas of dry air as it moves south and west towards the Mid Atlantic. The dry air it will encounter will act as a hindrance, evaporating much of the snow before it makes to the surface.

Stormscan showing snow entering the Ohio Valley this afternoon

Clouds will increase tonight but you should begin to see some clouds increasing on the horizon at sunset. Skies will be cloudy overnight and snow showers will move into the Appalachian Mountains around midnight. It will take areas east of the mountains longer to saturate, so many locations across the D.C. area won't even see any snow, but locations north and west will saturate faster and will have the chance for some light snow.

Forecast low temperatures Tuesday morning

Temperatures will be below freezing in the outlying suburbs west of D.C. and near or slightly above freezing in the D.C. Metro. Road temperatures should stay above freezing for the most part but some locations west of the Blue Ridge may experience a dusting IF snow falls heavy enough. The best chance for this would be in Washington County, MD, the Panhandle of VA and into the Shenandoah Valley in VA on lesser traveled roadways.

Potential Snowfall Accumulations (On the grass!)

While this is strictly model output, I do think there is the potential for a dusting in a few spots north and west of D.C. Tuesday morning. This will not be a big deal for the morning rush hour but it will definitely be interesting to see after the Vernal Equinox!

Just to remind you, March 25th of 2014 featured 1.7 inches of snow at Reagan National and 3.8 inches of snow at Dulles Airport, so it could be worse.

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Spring Has Sprung: The Vernal Equinox Friday

March 20, 2015 - 04:45 AM
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It's here!  Spring!  Astronomical spring arrives on Friday at 6:45pm, the vernal equinox.

And how welcome the season is after such a cold and snowy February. Unfortunately, Spring doesn't necessarily bring with it milder temperatures. The average high today is 59F but it appears temperatures today won't get out of the 40s!

The equinox occurs at the point when the sun crosses the celestial equator from South to North. The image above and below help to visualize this.

(http://earthsky.org/)

At the equinox, the geometric center of the Sun crosses the equator and this point is above the horizon for 12 hours everywhere on Earth.  Now when we think about the equinox, we often think about equal hours of daylight and darkness. The word equinox comes from the Latin word "aequus" meaning "equal" and "nox" meaning "night". Although it's close, there are actually a few more minutes of daylight on the equinox than darkness. Monday we had 12 hours of daylight and 12 hours of darkness.  Sunrise on Monday, March 17, 2012 was 7:16 AM and sunset was at 7:17 PM. So you may be asking, why wasn't Monday the equinox?

Well, it all comes down to that exact point when the center of the sun crosses the equator.  Sunrise and sunset occur when the top of the sun, not the center, is on the horizon.  That's why there are actually a few more minutes of daylight on the equinox.  Also, the earth's atmosphere refracts, or bends, light from the sun.  So, the top of the sun appears to be above the horizon when it is actually below the horizon. 

(http://calgary.rasc.ca/index.htm)

Today (Friday) we'll have a little over 12 hours of daylight (12 hours and 8 minutes), whereas Tuesday had 12 hours of daylight and darkness. From here on out, up until the summer solstice, we'll gain 2 hours 44 minutes of daylight.

The growing daylight and higher sun angle help promote warmer days.  Unfortunately, it can sometimes be a slow process in these transition months. Case in point, this March. The average high for the middle of March is about 55°. By the end of the month, the average high will be 61°.  The extended forecast starts out seasonable and then get a little warmer than average; however, another dip in temperatures for early next week. 

Happy Spring!

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Update: Snow possible for the 1st day of spring

March 18, 2015 - 11:29 AM
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The vernal equinox (i.e. spring) is Friday, so you would think we have seen the last of the wintry weather. Unfortunately or fortunately, depending on how you look at it, that is not the case!

The National Weather Service has issued a Winter Weather Advisory for areas northwest (in purple) and a Winter Storm Warning (pink) for Washington, Morgan, and Alleganyy counties in MD and Berkeley county WV.  A winter weather advisory indicates light snowfall could impact road conditions.  A winter storm warning is issued when heavy snow is expected and will likely cause travel impacts.  Elevation will play a huge role in this system with the highest accumulations farther NW. 

NWS Watches

The moisture is creeping in from the south, as you can see from this surface map.

ZZZZZ

The system should arrive during the overnight hours Thursday into Friday morning. Temperatures will be above freezing, but the air is dry, and as the moisture begins to fall, there will be some cooling of the air mass and wintry precipitation.

In House Model 6AM simulation of Snow

At this point, the Stormwatch 7 team cannot promise that we will see accumulating snow in the immediate metro area, but it is not out of the question.  Here's the latest StormWatch7 team's thinking:

Latest model guidance suggests around an inch of snow around the beltway with several inches possible farther north and west. I think we are in luck though because the local roadways are mild, which is a good thing. That means that even with an inch of snow possible, the amount we can really actualize (how much can accumulate) on the ground is minimal. I predict a scenario where a light coating could develop in mainly grassy areas. This setup lends itself to being an elevation-dependent situation. Meaning those who are hilltops and ridges have a greater likelihood of a couple of inches of accumulation and the potential for snow to make for slippery roadways.

As warmer air overspreads through the day, we all change over to a cold rain before it finally tapers off Friday night. The question remains though what, if any impact this may have on the region and in particular for the morning rush.  So here are the key points for now and we urge you to check back here for updates as we get new information. 

ZZZZZ

 As always, stay with the StormWatch7 weather team for more!

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Daylight Saving Time Sunday morning

March 6, 2015 - 04:14 PM
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It's that time of year again when you have to again wake up in the dark but at the same time experience a longer period of daylight in the evening. We enter Daylight Saving Time Sunday morning at 2am.

Sunrise on Saturday is at 6:32am and it sets at 6:07pm. Feel free to sleep in Sunday morning, as it will still be dark after 7am with sunrise at 7:31am. Personally I love having the extra hour of daylight in the evening hours instead with the sun setting Sunday at 7:08pm.

This is also a great time to change your batteries in your smoke and carbon monoxide detectors. IAFF will thank me for passing that along!

Sunrise and Sunset times Saturday and Sunday

As far as adding daylight to the mix, D.C. will experience 11 hours and 35 minutes of daylight Saturday, but in just 11 days there will be 12 hours of daylight.

Looking ahead, there will be 12 hours and 36 minutes of daylight by March 31st and over 13 hours of daylight by April 10th. That should be enough to look forward to for a little while. Enjoy the milder weekend!

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Winter Weather Thursday in D.C.

March 5, 2015 - 04:30 AM
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LIVE RADAR  |  HD CAMERAS  |  CLOSINGS  |  WARNINGS

Please tweet pictures or reports to..

@AlexLiggitt @JacquiJeras  |  @LaurynRicketts  |  @EileenABC7

@ABC7Brian @SteveRudinABC7  |  @DevonLucie

6:43PM: The live blog is about wrapped up for the night. Accumulating snow has ended across the region, with record daily snows at Dulles and Reagan Airports.

Tonight, low temperatures will fall into the single digits in the suburbs to low teens inside the beltway. Anything that isn't shoveled will freeze solid by tomorrow morning. Highs tomorrow should approach the 30 degree mark but with mostly sunny skies and a higher March sun angle, there should still be plenty of melting.

Temperatures should move into the 40s Saturday and 50s Sunday. Have a good night, enjoy the snow and stay warm!

5:46PM: Snowfall totals across the area have mainly been in the 4" to 10" range, with the highest north and west of D.C.

Here is the latest snowfall report list from the National Weather Service

5:14PM: Snow will gradually end over the next hour with a few flurries remaining through the evening. Reagan National recorded 4.6" for the day breaking the record of 4.4" from 1888.

3:16PM: The back edge of the snow is beginning to show up on Live Doppler Radar along the I-81 corridor. Light snow or flurries may continue to persist there but should taper off over the next hour.

Snow should begin to taper in the D.C. Metro around 5pm and closer to the Bay by 6pm. Patches of flurries or light snow showers may be possible through the early evening.

2:41PM: Sorry for the hiatus! The back edge of the snow is finally starting to show up on our StormWatch 7 Super Doppler. The heaviest snow is now south and east of D.C. and will continue to be there through the remainder of the event.

That being said, there is still moderate to heavy snow in D.C.  I expect another few inches around the D.C. Metro before the snow ends closer to 5pm or 6pm this evening.

Roads have a lot of slush on them right now, which will more than likely freeze solid in many places overnight with lows in the single digits to low teens. Record lows are expected to be broken at Dulles Airport and BWI Airport tomorrow morning.

12:09PM: A mesoscale discussion for heavy snow was again issued for the D.C. area concerning heavy snow banding continuing to push through the Metro and eventually south through the evening hours. As areas to the south and east haven't experienced as much snow yet, they aren't out of the woods yet and measureable snow is still expected.

11:25AM: The heaviest snow bands remain just north and west of D.C. and appear like they will move into the D.C. Metro over the next hour. Snowfall rates of 1 to 2 inches per hour will be possible.

Snow still looks like it will come to an end closer to 5pm or 6pm this afternoon. Here is a link to the latest snowfall totals.

10:43 AM:  Heaviest snowfall shaded in green.  Snowfall rates of 1" an hour in these locations.  This includes you, in Leesburg, Great Falls, Poolesville, Gaithersburg, and Rockville.

Live Super Doppler

9:57AM: Please, please, please try to beat this picture... It's amazing.

Finley seems to be enjoying the snow today!

9:23AM: You can check out the area roadways at the sites below.

Virginia: http://www.511virginia.org/

Maryland: Coordinated highways action response team

9:04AM: Sampling of current snowfall reports across the region...

Dulles Airport: 1.0"

Berryville, VA: 0.9"

Leesburg, VA: 0.5"

Herndon, VA: 0.7"

Inwood, WV: 2.0"

Columbia, MD: 0.7"

Hagerstown, MD: 0.7"

8:48AM: The Storm Prediction Center placed the D.C. area under a discussion which focuses on the likelihood for heavy snowfall this morning through the afternoon. Snowfall rates of an inch per hour or more will be possible through the day.

Please keep sending your pictures in via Facebook and Twitter!

7:58 AM:

66 eastbound at Markham. Sleet and snow mix- very slick!

ZZZZZ

 

 

 

7:49 AM:  Dulles Greenway snow covered and looking very slick in Ashburn - Loudoun county.  Thanks, Dave Johnson, for sending this!  Keep your pictures coming! #DMVSnow

Dave Johnson - Dulles Greenway - Ashburn, VA

7:32 AM:  Snow Emergency Plan in place for Howard, Carroll, Frederick, and Washington counties per MD State Highway Administration.  Roads are already snow covered in these areas.  Road and travel condition will only get worse over the next several hours.

MD State Highway Administration

7:15 AM update:

The rain to sleet to snow line is getting closer to D.C. metro area! Tune into www.wjla.com/weather for the latest radar!

ZZZZZ

 Hourly:

ZZZZZ

 

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Thursday Snow: Impact, Timing, Totals, and Could it Change?

March 4, 2015 - 07:58 AM
Comments

Here we go again. It seems every week in February and now into March we've had school closings, delays and disruptive snow or ice. A winter storm warning is now in effect for most of our area Thursday. 

Winter Storm Warning

Today is a dreary one with nothing but plain old rain. Temperatures will warm up and help melt our leftover snow. The changes will start overnight. Cold air will advance into the region and meet up with the stream of moisture that stretches all the way from the Northeast to Mexico! 

Water Vapor Satellite NOAA

Here is a timeline of the transition and when we expect snow across the region. It will start happening while you are sleeping. Areas north and west could wake up to a little snow on the ground, but don't be shocked if it's not accumulating yet until around sun up in the metro. Longer south of town.

Rain to Snow Timeline

The heaviest snow will be in the morning through midday. It tapers off late afternoon/early evening. Snowfall totals will range with the heaviest snow north of D.C. and lighter amounts to the south. Here is the latest Stormwatch7 forecast.  

Stormwatch7 Snow Forecast

COULD IT CHANGE? 

Yes. The key thing to watch is how quickly cold air rushes in tomorrow and how much moisture will still be in place when that happens. A prolonged period of sleet or wintry mix would require us to shave down the numbers.  At the same time, snow bands will likely set up somewhere across the region and could bring a slightly higher burst for bigger numbers. Our forecast reflects the most likely totals and why we always give you a range of numbers. If you are "shopping around" comparing forecasts, make sure you note that source. There are a lot of maps floating around on social media from people that do not have a meteorology background. No matter the numbers, the impact will be significant. School closings are likely. Government closing.. probably. You can check the latest on this link. Travel will be bad through much of the day Thursday with snow covered roads and poor visibility at times. Flights will get cancelled. The later in the day your flight, the more likely you will get out as snow should ease late day or early evening.  If you are winter weary, check out our 7day forecast!  A nice break over the weekend into next week.

 

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Plan Ahead for Slick Spots This Evening but Light and Widespread

March 3, 2015 - 11:31 AM
Comments

WINTER WEATHER ADVISORY NOW CANCELED FOR A GOOD PORTION OF THE REGION

ZZZZZ

Not impressed. Yes, I can hear the keyboard typing with comments now but this is how the weather rolls in D.C. –once you think you nailed the forecast – things have to go ahead and change. We always have to keep an eye on the latest data because of this fact (and this is also why we wait just a little while longer to put out snow totals).


I’ll just come out and say it – although there will be slick spots out there this afternoon and tonight, anything we get will be fairly widespread and pretty light. We are really dry out there and temperatures are rising. The precipitation will be delayed slightly because it is evaporating before it even hits the ground. Considering it will take longer to moisten the atmosphere, temperatures will continue to rise.

ZZZZZ

I would still plan ahead for some light icing during the evening commute and use caution but I believe a good majority of the roads around the D.C. metro area and south will just be wet with some light rain. However, please watch for the regular spots – bridges, overpasses, underpasses and exit ramps for a better chance of some light glaze. (Don’t worry – the StormWatch7 team will continue to update through your evening commute to get your home safely).


Temperatures will rise overnight and we will have some spotty rain showers during the overnight hours. More scattered showers will move in through the day tomorrow as temperatures move on up to the lower 50s in spots! Rain could be heavy at times which could lead to some flooding around the region (rain plus melting of the existing snowpack).

We are still on point to see some snow/sleet move in on Wednesday after midnight as a cold front will unleash more arctic air upon us for Thursday. In fact, temperatures drop on Thursday from the 30s and into the 20s (winds will pick up as well making it feel like the teens and single digits). Any sleet will then turn to snow showers and those are forecast to hang around for much of the day on Thursday which means accumulating snow around the region. It is too early to push out snow totals so please don’t buy into the hype on the internet just yet (look how quickly things changed today). If I had to go out on a limb right now, I would count on delays and cancelations on Thursday as the way things look now. However, we will update you with snow totals early Wednesday morning with all the latest information!

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Get Ready for a Bumpy Ride- Rollercoaster of Weather this Week

March 2, 2015 - 10:52 AM
Comments

Alright March – stop it. This is where we should begin to look forward to spring: days are getting longer, next Sunday Daylight Saving Time begins, it is actually the beginning of meteorological spring, etc. However, you give us one day this week that will feel like spring-wedged between days that we have winter weather activity. C’mon March!

This week will be a roller coaster ride so get ready. The forecast is subject to change (as always) but I want to give you an outline of what to expect. The reason for the change is that there are a lot of timing issues that we will have to watch. For example – how much ice could we accumulate on Tuesday evening before warm air takes over? That is an example of just one of the questions we have this week but bear with me and just keep an eye on the forecast. Here is what you can expect in the very least.

After some decent melting through the day on Monday as temperatures climb through the 40s, we will once again have some icy spots tonight with overnight lows forecast to drop into the teens and 20s. We will start off on the mostly clear side tonight with high pressure slipping east from the Midwest. However, clouds will be on the increase towards daybreak Tuesday.


TUESDAY


The first half of Tuesday looks fine (besides some morning icy spots). Temperatures will move into the mid-30s through the day ahead of our next system. A warm front will slide in from the south and west through Tuesday night as high pressure scoots off the Mid Atlantic coast.

ZZZZZ

There will be plenty of clouds around and cold air in place at the surface. Precipitation will begin to fall from the southwest to the northeast after the lunch hour into the early afternoon. It looks to start off as maybe some snow but a quick transition to sleet and freezing rain.

Warm air will eventually filter in from the south and west but the question remains: when can that warm air win out at the surface? At that point, we will begin to see a transition to rain as temperatures actually go up Tuesday night into Wednesday. However, at this point, expect some icy accumulation for the evening commute on Tuesday.

ZZZZZ

Caption: Probability of 0.01” or more freezing rain/ice accumulation through 1 a.m. Wednesday morning. D.C. has a 50%-60% chance of 0.01” or more of ice accumulation through 1 a.m. Wednesday. Chances of that happening increase north and west of D.C.


WEDNESDAY


This is the most spring like day we will experience this week. Temperatures will shoot into the 50s as the D.C. region will be in the warm sector. However, there will be some scattered rain showers around throughout the day.

There could be a decent amount of rain coming down in areas so we will have to watch for potential localized flooding throughout the region as the snow pack that is left begins to melt. I do not expect widespread flooding but at least the potential for again, some more localized flooding.

ZZZZZ

WEDNESDAY NIGHT INTO THURSDAY


A strong cold front will then slowly move through the region and cold air will begin to move back in from the north and west. An area of low pressure will form and ride along the front after it sweeps through our region and sags to the south and east of the D.C. area. This will give us a chance of some wet snow Wednesday night into Thursday morning. In fact, there could be some accumulating snow around by Thursday morning. Temperatures on Thursday will only rebound into the lower 30s, not far off from our overnight low on Wednesday night of around 30 degrees. Any snow will move out during the morning with arctic high pressure pushing in. Expect a breezy day on Thursday as winds pick up.

High pressure will stick around Friday and Saturday giving us sunshine and gradually warming temperatures. Plan ahead and keep it here for the latest forecast as we continue to tweak it!

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