The average monthly temperature so far in June is a half degree below average at 72.8 degrees! This is a far cry from last June when highs were a whopping 4 degrees above average! Things will change as we slide into summer this week, so don’t get too used to the comfortable temperatures.
What typically causes East Coast heat waves to develop is a sprawling high pressure ridge that moves in at the surface and aloft. This deflects the jet stream well north into Canada. Surface high pressure positioned off the East Coast allows south to southwest winds to be directed up the Interstate 95 corridor. The ridging also suppresses cloud cover, allowing the mercury to rise and the heat index to be unrelenting.
This scenario will pan out by midweek. A few impulses in the upper atmosphere; one in the Midwest weakening as it heads for the East Coast Monday and another in the Northern Plains will eventually move into Canada. As this happens, warm air will filter in from the south Wednesday. The heat will remain Thursday but get bumped down just a notch as a very weak cold front tries to move in from the north.
What all this boils down to is a stretch with temperatures at or above 90 degrees, beginning on Wednesday. As a matter of fact, Wednesday (the first official day of astronomical summer) and Thursday look to be the hottest with near record high temperatures.
Here are the records that could be tied or exceeded: Wednesday, June 20th… 97 degrees at Dulles International and 99 degrees at Reagan National. Thursday, June 21st…. 98 degrees at both Reagan National Airport and Dulles International
The heat combined with dew points in the lower 70s will yield heat indices between 100 and 110 degrees with heat related advisories quite possible for Wednesday and Thursday. Remember to wear light-colored clothing, avoid exercising or outdoor labor if at all possible during the warmest part of the day, 10 a.m. to 4 p.m. and drink plenty of water. Also, check on the elderly, make sure pets stay inside as often as possible and never leave your child in the car.
So far, there have been 5 days at or above 90 degrees at Reagan National this year and 3 so far this month. In a typical summer there are 25 of these hot days. If you remember not too long ago in the summer of 2010 there was 57 days’ worth of 90 degree heat, which tied for the most in a given summer and was 12 days off the record for an entire year.
While temperatures will “cool down” a bit following the Wednesday-Thursday heat episode, highs will still flirt with the 90 degree mark through the weekend.
Stay cool and be sure to tune into WTOP Radio and ABC7 News for the latest forecasts and any heat-related advisories that may be issued for Wednesday and Thursday.
A beautiful day in the mid-Atlantic today as you can see in that great TERRA satellite image from 400 miles above us.
We have a live WeatherBug camera at Rehoboth Beach Delaware that you can check out on our new camera page. But what is beautiful and sometimes fun is to watch a time-lapse of the sky or as here the boardwalk and beach at Rehoboth. We recorded one image about every 4 seconds so enjoy the ”boardwalk races” recorded over about an hour and one half this beautiful Friday.
The “Star-Spangled Sailabration” marks the start of Maryland’s three year commemoration of the bicentennial of the War of 1812. The weeklong event began on June 13th and will run through the 19th. Baltimore’s Inner Harbor will be home to an international parade of more than 40 tall ships and 12 naval vessels from 12 Countries. The event offers plenty to keep you entertained and busy featuring free tours of the ships, waterside festivities, an airshow featuring the famous Blue Angels and much more. To find a complete list of the scheduled events and times, parking, hotels, and more (Click Here).
The weather this weekend couldn’t be more perfect for this event with daytime highs around 80 degrees if not into the low 80s with low humidity. As luck would have it the “Sailabration” will wrap up Tuesday just before the real June heat and humidity arrive.
My friend Jacob Wycoff with Weather Bug was kind enough to send me a great time-lapse from yesterday with a great view of the Inner Harbor as the ships arrive. Enjoy and have a good weekend.
A former employee and friend Joe Witte, who is now working at NASA, was nice enough to pass along this video courtesy of NASA SDO. Whether you are a space junky or simply enjoy seeing some of the amazing sights from space you should take a few seconds to view this piece of video they created. It has even been set to music, so take a small break and check this out.
Here is a more technical description of what you are looking at by LittleSDOHMI.
“A shape-shifting active region; AR1504 rotated over the eastern limb of the Sun on June 9 and started its journey across the Earth facing side of the Sun with a M-class solar flare. Between June 9 and 14 a total of 5 M-class flares were observed, of which the long-duration June 13 flare hurled a coronal mass ejection (CME) our way.”
“This video shows the shape-shifting path the sunspots of this active region have taken. The electric currents in the Sun, as well as in planets and galaxies, generate magnetic fields. Sunspots, temporary disturbances in the Sun's photosphere, are the most visible advertisement of the solar magnetic field. They appear dark because temperatures are considerably lower than in surrounding areas. Sunspots occur where the magnetic field lines emerge from the inside of the Sun to form expanding loops above its surface.”
“Sunspots usually show up as small forms that are irregularly shaped, and grow within days or weeks to their full size. While they can last weeks or months, they do eventually disappear, often by breaking into smaller and smaller sunspots.”
“The video also takes a look at the five M-class solar flares from the June 6 to 14, 2012.”
Although the weekend will be dry, it will certainly be much "cooler" compared to last weekend. Instead of highs in the upper 80s to low 90s, highs will only reach the low 70s by the ocean and upper 70s by the bay.
An Easterly wind will still be prevalent over the weekend, so that will keep temperatures down a bit, as the wind blows from the relatively cool ocean waters onshore. Water temperatures along the Atlantic, near Bethany, Ocean City, and Assateague are near 70°. Down by Virginia Beach and the Outer Banks, water temperatures are a few degrees warmer. Even though temperatures will be in the 70s, expect a fair amount of sunshine with periods of cloudiness. Still wear the sunscreen and be mindful of rough surf that will be possible with the onshore flow. Waves will be around 4-5 ft. Rip currents may be a concern - here are rip current risks for the New Jersey and Delaware beaches and for Ocean City, MD to Duck, NC.
Atlantic Beach Forecast
Along the Chesapeake Bay, temperatures will be slightly warmer than near the ocean climbing into the upper 70s. Winds will still be out of the East, so that may cause some choppy waters along the Bay. Keep that in mind if you're taking the boat out. Otherwise enjoy the sunshine and comfortable temperatures.
It's not breathtaking wave photography or as cool as underwater dogs, but this is neat in its own right. I'm a geek for a good timelapse from our rooftop camera, and this one is worth watching. By the way, sunrise was at 5:42 a.m.
We're feeling the "aaahhh" on Wednesday -- drier, more refreshing air makes it feel quite comfortable for mid June. Think about how it feels now outdoors compared to what it was like 24 hours ago. A complete change! A 20+ degree dewpoint change!
We talk about the dewpoint often, but do you remember what it means? You can go to one of our previous blogs for a more thorough explanation, but the graphics below help sum up what the dewpoint is all about. Here are the dewpoint temperatures on Wednesday.
Wednesday Midday Dewpoint Temperatures
Before the front pushed through, shortly after midnight Tuesday, dewpoint temperatures were in the 70s. After winds shifted to the North, dewpoint temperatures dropped, as the drier air filtered in. Temperatures are actually a few degrees warmer than on Tuesday; however, a drastic drop in the amount of moisture in the atmosphere makes it feel completely different. Here is the 24 hour dewpoint change:
Tuesday Midday Dewpoint Temperatures
The dewpoint temperature is relative to the temperature. The closer the dewpoint temperature to the air temperature, the more moisture in the atmosphere, which can result in the "muggy and sticky" feeling you may experience, especially in the summertime.
Enjoy the drier air while it lasts... and the lower dewpoints!
Since the birth of the Air quality Program in 2010, the Metropolitan Washington Council of Governments in association with the Maryland Department of the Environment, have combined to produce daily air quality forecasts for our region.
I am sure you have seen them on TV and heard them discussed on the radio during the summer months when the heat, humidity, and stagnant air can produce dangerous health issues.
Well up until June 5th of 2012 the National Weather Service has issued an air quality alert or an AQI whenever the index reached greater than 100 which or Code Orange. Code Orange AQI impacts those who are unhealthy or sensitive to unhealthy air quality.
This new “modification” will require the National Weather Service to only issue air quality advisories for the region when the AQI reaches 150 or greater. This would include Code Red, Purple, or Maroon. This range covers air quality that is classified as unhealthy, very unhealthy, or hazardous.
Rest assured that even if the National Weather Service doesn’t issue an air quality advisory, for those of you that are unhealthy or sensitive, that you can always tune in to ABC 7, NewsChannel,8, wjla.com, and WTOP to continue to get that information daily during the summer months.
OK - so it's June and before the second weekend of the month, the highest temperature, occurred on Friday, the 8th making it to 85°. The average high temperature for the beginning of June is near 81°. Three days have made it into the low 80s, but the rest of June has had highs only in the 70s! Certainly an anomoly to a typical D.C. start to June when we usually start to feel more heat and humidity. Speaking of humidity, dewpoints to start June have been in the upper 40s to low 50s -- almost unheard of, but very refreshing.
D.C. had it's first 90 degree day of 2012 on Memorial Day, May 28th. Last year, May 26th was the first 90 degree day, making it to 92°. Unlike this year, it was ahot start to June! In fact, the first heat wave (three consecutive days of 90 degree highs or higher) occurred May 30 (96°), 31 (98°), and June 1st (98°).
The next stretch of 90 degree days, in 2011, was June 7th through the 12th. The 8th and the 9th were both record setting days. The chart below shows the six day heat wave and the high temperature departure.
June 2011 Highs & High Departures
2012's start to June was much different. Take a look at the chart below and see the unbelievable difference in temperatures! Now highs through the upcoming weekend (9th, 10th, and 11th will likely climb to near 90°), but still the first few days are a rarity for June.
2012 June Highs & High Departures
June 5th was 10 degrees below average. Highs this weekend will make to around 90 degrees, but no where near record breaking temperatures. So if you're thinking it's hot this weekend, just remember this time last year was a lot hotter!
"Jason, all, This is a critical question and discussion. I had someone Tweet to me that Friday they were evacuated to the basement of the National Building Museum because of a tornado warning. The warning WAS NOT for downtown DC. TORNADO WARNING sets off all sorts of alarms and fears and decisons, some of which might result in more injury than from an actual small whirwind. If NWS offices in Missouri and Kansas, after the tragic outbreaks of last year, can issue apocalyptic warnings for a possible extreme event with wording such as "EXTREMELY DANGEROUS TORNADO WITH COMPLETE DEVASTATION LIKELY. ... SEEK SHELTER NOW! ... MOBILE HOMES AND OUTBUILDINGS WILL OFFER NO SHELTER FROM THIS TORNADO — ABANDON THEM IMMEDIATELY." with today's technology and science we can, on the other side, issue wording that conveys the degree of danger and risk not just "tornado warning" without anything else. Example: "Doppler radar is detecting a strong thunderstorm likely producing a small whirlwind or small tornado. Winds of 50-85 mph are possible within the warned area. Stay inside and away from windows" Or radar and spotter observations show a DANGEROUS [emphasis mine] tornado likely producing major damage. Head to a storm shelter, bathroom or basement in the warning area. Or " A LIFE THREATENING TORNADO [again my emphasis] is heading toward. . . seek a safe room, basement in a very protected area or underground shelter. This will be a devastating tornado" We do have better skill now at seeing the likely strength of tornadoes. Beating a false alrm rate of 70% by verifying a short small EF-0 in the woods should not be a goal. Helping people make the best decision, such as not falling down the stairs at the National Building Museum for no warning or not getting into a serious traffic accident because all the driver hears is "TORNADO WARNING" IS a goal. A "correct" forecast lacking good communication which results in a bad decision or unecessary action is a useless forecast. There are winter storms and big winter storms. There are small whirls, detected more and more, and the real McCoy tornadoes. We all have a role in effectively communicating the real danger, beyond just yelling TORNADO WARNING so everyone will make the best decision. Some studies have shown 60% of the U.S. population still get confused between "watch" and "warning". The science has made great advances we can make similar advances in communicating weather risk and danger. "TORNADO WARNING" with 70% false alarm rate needs fixing"
Clark Little Photography was kind enough to let me feature some of his artwork in a gallery above. The idea to feature his work came to me as I remember my cousin receiving his book for Christmas a few years ago. My cousin, who is huge into bodyboarding in Austrailia, also loves photography and would love to eventually run a surf photography business, so I knew Clark Little must make some great works of art. The best part of making this gallery was finding out it cooresponded with World Ocean Day which is today.
Here's a little video showing how Clark takes his photos. This isn't really something you're likely to see while strolling the beaches on the east coast...just saying. The beaches from Atlantic City to the Outer Banks, this weekend, will be just a little more tame.
Thinking about getting away this weekend? Maybe getting away from the heat?! Well it's going to be hot across the region, but at least by the water it will feel a bit cooler and you can always jump in the bay/lake/river/ocean to cool off!
With the changing weather pattern, highs will climb into the upper 80s to low 90s inland; however, it will be a few degrees cooler along the coast. A broad area of high pressure will build into the region, which will bring hotter temperatures, but plenty of sunshine. Great for all weekend, outdoor activities!
Let's start at the Northern beaches and work South - then we'll come back to the Chesapeake Bay. Atlantic City, Rehoboth, Dewey, Bethany, and Ocean City will have lots of sunshine and high temperatures in the mid 80s. Ocean temperatures are in the mid 60s to low 70s. Mainly Westerly winds will keep temperatures, even at the beaches, fairly warm/hot.
Weekend Ocean Beach Forecast
Farther South, to Virginia Beach and the Outer Banks, will be great beach spots, as well. More sunshine, albeit a few afternoon cumulus clouds, and highs into the 80s. Water temperatures are a little warmer, at around 75°.
Around the Bay, water temperatures are in the low to mid 70s and afternoon highs will be in the upper 80s West of the Bay, but on the Eastern side temperatures will reach the low to mid 80s with Westerly winds blowing off the relatively cooler Bay temperatures.
Weekend Bay Forecast
With the sunshine, whether you're looking to cool off at the beach or the pool, make sure you wear plenty of sunscreen with the high UV index.
Looking to surf? Not great swells for that, but could have fun boogie boarding! The water should be relatively calm with 1 foot waves, which should bode well for boaters.
Have a great weekend - Enjoy the sunshine and stay safe in the heat!
Have you taken advantage of our recent wonderful June weather? I don’t mean necessarily taking a day off but maybe just looking at the great sky.
Going outside can be really good and healthy for you. We, especially young people, are spending more and more time inside and it may be hurting our creativity. A recent paper cited in this interesting article in The Wall Street Journal, gave hikers a standard creativity test before a multi-day hike. After four days of hiking and enjoying nature (and the sky of course) hikers immersed in natural surroundings showed a 50% increase in performance in the creativity test. Other studies have found that some people and young children suffering from stress and emotional problems get much calmer just lying in the grass and watching the sky for a while. Other studies have shown that even a patch of grass within inner city housing projects can have beneficial emotional and intellectual benefits. As the Journal article author Jonah Lehrer writes, “Cities are here to stay; so are smartphones. What this research suggests, however, is that we need to make time to escape from everyone else, to explore those parts of the world that weren’t changed for us. It’s when we are lost in the wild that the mind is finally at home”. Give it a try and watch the sky and nature for a bit and get lost in something that may be good for your health in many ways.
Regardless of your views on climate change, a new peice of technology has been unveiled - the supercomputer, Yellowstone. No, it's not from the National Park, but to climate scientists, meteorologists, and the like, it's a huge advancement in forecasting - climate forecasting, in particular.
You may have heard of the supercomputers that bring us current, numerical weather prediction. Meteorologists rely heavily on these computer models in order to forecast. The accuracy of weather forecasts has increased over the years, as the technology has advanced. The newest supercomputer released is named Yellowstone, and was recently shipped to NWSC (NCAR Wyoming Supercomputing Center, shown below).
NCAR-Wyoming Supercomputing Center: Where Yellowstone will reside
The new Yellowstone supercomputer operates 1.5-quadrillion-calculations-per-second (a 1.6 petaflop system: flop - meaning floating operations per second). So how does that compare to most of our personal computers? That's about a trillion more operations per second! That's a lot of computing power!
IBM Supercomputers - NOAA
Since the computing power is much higher in Yellowstone, compared to other supercomputers, the amount of data it will be able to store and generate will greatly enhance the simulation resolution. Instead of calculating climate variation on a continental scale, Yellowstone will be able to study regional changes. The higher simulation resolution will take into effect more local and regional climate factors, such as coastlines, mountain ranges, vegetation, snowpack, and precipitation.
With the focus on a smaller scale and details of a local climate, scientists will be able to see better into the future.
It appears many people are intrigued with the cool, vertically billowing clouds we’ve seen the last few days in the afternoon (I know they have captured my attention!). The day starts out sunny and then bam…. by early afternoon we have been getting puffy clouds. By mid-to-late afternoon then a few showers fall from these clouds.
Well, in order to understand the science behind this week’s cloud formation let’s first look at the large scale weather set up and then trickle down to what the atmosphere above us has been looking like since the weekend to generate such cool clouds.
A low pressure in the upper-levels is helping to drag the jet stream, or zone of high velocity winds in the upper-levels, to the south of the region. This is allowing cooler air from Canada to seep south into the Mid-Atlantic.
Just like spokes going around a wheel, there are weak disturbances that are much smaller in size rotating around the main low pressure (circled in the upper-level image below). As these disturbances rotate around the low like the spokes on a wheel would move around a bicycle tire, it sparks showers and storms during the day.
(Story Image: Upper-level chart from Tuesday morning showing winds aloft, the upper-level low in the Northeast and the jet stream winds)
The next time Venus will transition in front of the sun will be 2117. Chances are if you are here when that happens, you're not alive yet. Who knows, maybe I can make it to 134 years old... If you're not going to make it that long, then you might as well check out the awesome pictures and videos from Tuesday. Here is a great video from the Solar Dynamics Observatory.
0248 PM TORNADO 2 SE MOUNT AIRY 39.36N 77.14W
06/01/2012 CARROLL MD NWS STORM SURVEY
A BRIEF TORNADO...RATED EF0...STARTED JUST WEST OF THE
INTERSECTION OF TWIN ARCH ROAD AND OLD FREDERICK ROAD
AND JUST NORTH OF I-70...CONTINUING NORTH UNTIL IT
DISSIPATED AFTER CROSSING TWIN ARCH ROAD. PATH LENGTH
0.4 MILES...MAX PATH WIDTH 100 YARDS. SPORADIC DAMAGE
ALONG THE PATH CONSISTED OF SEVERAL UPROOTED TREES AND
SNAPPED LIMBS. NO STRUCTURAL DAMAGE WAS OBSERVED.
A TORNADO...RATED EF1...STARTED ON WEST WATERSVILLE
ROAD JUST NORTH OF OLD FREDERICK ROAD AND MOVED
NORTHEAST BEFORE DISSIPATING NEAR THE INTERSECTION OF
WATERSVILLE ROAD AND FLAG MARSH ROAD. PATH LENGTH 1.4
MILES...MAX PATH WIDTH 200 YARDS. DAMAGE CONSISTED OF
NUMEROUS TREES UPROOTED AND SNAPPED WITH POWER LINES
DOWN. AN AREA OF INTENSE DAMAGE WAS NOTED IN THE 500
BLOCK OF WEST WATERSVILLE ROAD...WHERE APPROXIMATELY 30
TO 40 LARGE HARDWOOD TREES UP TO 2 FEET IN DIAMETER WERE
UPROOTED OR SNAPPED
*** 2 INJ *** RATED EF-1. PATH LENGTH 1.25 MILES AND
WIDTH 0.25 MILES.
0706 PM TORNADO 1 SSW FORT MEADE 39.10N 76.74W
06/01/2012 ANNE ARUNDEL MD NWS STORM SURVEY
REPORT HAS BEEN AMENDED TO REFLECT THE START OF THE
PATH ASSOCIATED WITH THIS TORNADO. DAMAGE CONSISTED OF
SNAPPED OR UPROOTED TREES...SNAPPED LIMBS AND MINOR
DAMAGE TO SIDING ON EAVES. NORTH OF DISNEY ROAD...DAMAGE
WAS QUITE SPORADIC...SUGGESTING THE TORNADO WAS NOT IN
CONSTANT CONTACT WITH THE GROUND. TORNADO WAS OBSERVED
CROSSING WESTERN PORTION OF BWI AIRPORT RUNWAY AND
LOFTING TREE DEBRIS BY TOWER PERSONNEL.
0726 PM TORNADO 1 NW SPRINGDALE 38.94N 76.85W
06/01/2012 PRINCE GEORGES MD NWS STORM SURVEY
BRIEF TORNADO WAS DOCUMENTED EAST OF THE US50 AND
BELTWAY INTERCHANGE IN PRINCE GEORGES COUNTY. DAMAGE WAS
LIGHT AND CONSISTED OF UPROOTED TREES AND SNAPPED LIMBS.
DAMAGE WAS CONSISTENT WITH EF0 WIND. PATH WIDTH WAS 50
11:22 PM: Final update from the Live Blog -- expect the last of the showers to push East and clearing skies to follow.
10:30 PM: Everything really settling down out there. TORNADO WATCHES in effect through 2AM for the Washington metro and points East; although, I wouldn't be surprised if these watches were dropped early.
9:45 PM: Last line approaching the D.C. metro area now. Most likely through the area within the hour.
Live Super Doppler at 9:48 PM
9:17 PM: Here's another photo we received earlier from Woodbridge, VA. Looks like a funnel cloud behind the two houses.
Viewer photo from Woodbridge, VA
9:02 PM: TORNADO WARNING in effect for parts of Baltimore, Howard, and Montgomery counties until 9:30 PM. Storm 5 miles NW of Mount Airy & 11 miles North of Damascus. This is VERY FAST moving storm -- 50 mph!
Live Super Doppler 7 at 9:04 PM
8:54 PM: SEVERE THUNDERSTORM WARNING for Charles, Prince Georges, Fredericksburg, Culpeper, Fairfax, Fauquier, King George, Orange, Prince William, Spotsylvania, and Stafford counties until 9:30 PM.
8:45 PM: Take a look at local rainfall totals from our WeatherBug network. This is why we are concerned with flash flooding. A LOT of rain in only a few hours. Be safe on the roads and NEVER drive through flooded streets.
WeatherBug rainfall totals as of 8:30PM
8:30 PM: THE FLASH FLOOD WARNING FOR D.C., MONTGOMERY, FAIRFAX, FALLS CHURCH, ARLINGTON, ALEXANDRIA, AND NORTHERN PRINCE GEORGES COUNTIES IS EXTENDED THROUGH 11:30PM.
8:20 PM: TORNADO WATCH EXTENDED ANNE ARUNDEL, CALVERT ,CARROLL, CHARLES, FREDERICK, HOWARD,
MONTGOMERY, PRINCE GEORGES, AND ST. MARYS UNTIL 2AM.
NWS Watch Map
7:48 PM: Still watching two lines move through the area. The first line extends from Baltimore and Southwest along (and just East) of I 95. The second line, along the cold front, is stretching from Martinsburg, south through Northern Prince William county. Still enough upper level dynamics for storms to become severe or tornadic. Flooding, now, the biggest concern across the region.
Live Doppler as of 7:45PM
7:22 PM: Newest TORNADO WARNING near BWI. Southern Baltimore County and Baltimore City and Northern Anne Arundel county under the Tornado Warning until 7:45 PM. SEVERE THUNDERSTORM WARNING for Washing, Berkeley, and Jefferson counties until 8 PM.
7:10 PM: This is the next line of storms we're watching. Just South of La Plata. The brighter reflectivity (especially where you're seeing the purple in the middle of that line of storms) indicates the possiblity of hail. No suggestion of rotation at this time.
7:00 PM: TORNADO WARNING UNTIL 7:30 PM - NOTHERN PRINCE GEORGE'S, NORTHWESTERN ANNE ARUNDEL, AND SOUTH EASTERN HOWARD COUNTIES.
Live Super Doppler 6:59 PM
6:34 PM: Thanks to our viewers sending us pictures of the storms and damage (we remind you, your safety comes first, so do not put yourself in harms way when taking these photos). Here's one we received from a viewer in Columbia, MD.
6:28 PM: Latest radar shows deluge of rain right over the District stretching through Southern Montgomery County. FLASH FLOOD WARNING continues through this entire area (where you see counties highlighted in maroon color) until 9:15 PM.
Latest radar as of 6:30 PM
6:15 PM: NEW TORNADO WARNING ALONG A LINE OF STORMS MOVING TOWARDS PAW PAW. TORNADO WARNING FOR NORTH FREDERICK, WEST MORGAN, NORTHEAST HAMPSHIRE, AND EAST ALLEGANY UNTIL 6:45 PM.
Live Super Doppler 7 at 6:18 PM
5:22pm Update: 7,700 are reportedly without power in NE D.C and another 2,722 out in SE D.C.
4:56pm Update: Tornado Warning issued for Washington until 5:15 p.m.
3:48pm Update: About 3,500 are reported without power in Stafford County.
3:45pm Update: WTOP reports that a flash flood watch has been issued for the entire D.C. area until midnight
3:34pm Update: All flights into Dulles, Reagan and BWI airports are halted until 3:45 p.m.
3:22pm Update: A flash flood warning is in effect for Frederick, Montgomery, Carroll and Howard counties until 6:15 p.m.
UPDATE: NWS has issued a tornado warning for eastern Carroll County until 3:45 p.m.
2:45pm Update: A Severe thunderstorm warning has been issued for the counties of Frederick, Howard, Loudoun and Montgomery. In effect until 3:30 p.m.
2:30pm Update: Tornado warning has been issued for southeastern Frederick county in north central Maryland, Northern Montgomery County in central Maryland, southwestern Carroll County in north central Maryland, northwestern Howard County in central Maryland until 2:45 p.m.
12:38pm Update: There is now a Moderate Risk for severe weather this afternoon over the DC area. The tornado threat has been upgraded a bit from 10% to 15% for the outlook area. The SPC has stated that there is chance for an isolated strong tornado this afternoon and evening.
Moderate Risk Region Friday
Here is a look at the HRRR Model run this afternoon and evening. The first line which is already on Doppler is below, moving through the region by 1 or 2pm. After that, there may be some clearing before the next system this evening.
2pm HRRR Model Depiction
This is the depiction for this evening. At this point, we think there is a chance for heavy showers and storms, potentially severe, between 5pm and 9pm tonight. Something our team will be watching for is a Quasi-Linear Convective System with Line Echo Wave Patterns in them. Basically, those are just fancy words for a line of strong thunderstorms with some embedded areas of rotation.
The biggest threats today will be damaging wind gusts and flash flooding. There is a secondary risk for isolated tornadoes. Check out the Storm Prediction Center this afternoon for the latest on the highlighted risk area and to see if there are any watches for our area.
Live Super Doppler 7is already picking up on some heavy rain southwest of D.C. Be sure to check on it throughout the day.
There are numerous things you can do to help us out today. First and foremost, stay safe. Heed the watches and warnings that are expected to come out later today. Be sure to follow us on Twitter at our various accounts and tweet to us any damage reports, flooding, pictures, video, anything you want. We will post anything we come across that will be of value to you. Here are our accounts below.
1:15pm UPDATE: From the Storm Prediction Center...Tornado Watch Likely… Thunderstorms will increase through the afternoon in a very moist and increasingly unstable air-mass. Isolated storms will first pose a threat for isolated severe weather in the form of hail and winds. Additional severe storms are likely as a forced squall line develops east of the Appalachians later this afternoon. Deep shear and tornado potential may increase across the entire region from late afternoon into the evening. One or more tornado watches will likely be issued over the next 1-2 hours. - Meteorologist Chris Naille
1:35pm Update: Tornado Watch Until 9PM For Frederick County, MD, Loudoun, Fauquier, Culpeper, Madison and all Counties north and west. A second watch box will likely be issued at some point over the next 1-2 hours which will likely include the rest of the viewing and listening areas.
Credit: National Weather Service
1:55pm Update: The entire region is now under a Tornado Watch Until 9PM
2:59PM Update: Severe storms have already developed across the region. TORNADO WARNING IN EFFECT UNTIL 3:45PM FOR CARROLL COUNTY. A SEVERE THUNDERSTORM WARNING in effect for Southeastern Frederick, Northern Montgomery, Carroll, and Norwestern Howard County until 4 PM.
3:12PM: TORNADO WARNING CARROLL, HOWARD, MONTGOMERY COUNTIES UNTIL 3:45 PM. TAKE SHELTER IMMEDIATELY.
Live Super Doppler 7 at 3:12PM
3:24 PM UPDATE: SEVERE THUNDERSTORM WARNING UNTIL 4:15 PM
THE DISTRICT OF COLUMBIA...
SOUTHEASTERN MONTGOMERY COUNTY IN CENTRAL MARYLAND...
CITY OF FALLS CHURCH IN NORTHERN VIRGINIA...
ARLINGTON COUNTY IN NORTHERN VIRGINIA...
CITY OF ALEXANDRIA IN NORTHERN VIRGINIA...
NORTHERN PRINCE GEORGES COUNTY IN CENTRAL MARYLAND...
WESTERN ANNE ARUNDEL COUNTY IN CENTRAL MARYLAND...
SOUTHEASTERN HOWARD COUNTY IN CENTRAL MARYLAND...
EASTERN FAIRFAX COUNTY IN NORTHERN VIRGINIA...
3:40 PM UPDATE: Got a picturer of a funnel cloud in Sterling, VA. Numerous storm cells across the region producing heavy rain, flash flooding, and some rotation.
ABC7 Photo of Funnel Cloud in Sterling, VA
3:45PM UPDATE: Flash Flood Watch in effect for the entire viewing area until MIDNIGHT tonight. Exteremly heavy rain will fall with these storm cells that will continue to develop through the rest of the night.
4:01 PM UPDATE: Tremendous video from a viewer, Scott Gast, in Charles County.
4:48 PM UPDATE: TORNADO WARNING IN EFFECT UNTIL 5:15 PM FOR WEST PRINCE GEORGES COUNTY AND THE DISTRICT. TAKE SHELTER IMMEDIATELY. LATEST RADAR IMAGE.
Live Super Doppler 7 as of 4:48 PM
4:57 PM UPDATE: TORNADO WATCH REMAINS IN EFFECT FOR THE ENTIRE VIEWING AREA UNTIL 9 PM & A FLASH FLOOD WATCH FOR THE ENTIRE VIEWING AREA UNTIL MIDNIGHT. SEVERE THUNDERSTORM WARNING NOW IN EFFECT FOR City of Fairfax, City of Manassas, City of Manassas Park, Fairfax, Fauquier, Prince William, Stafford, VA until 5:30 PM.
5:07 UPDATE: TORNADO WARNING REMAINS IN EFFECT UNTIL 5:15 PM FOR WESTERN PRINCE GEORGES COUNTY AND D.C. You can see a definitive hook in this storm cell which is indicitive of rotation.
Live Super Doppler 7
5:12 PM UPDATE: NEW TORNADO WARNING FOR CENTRAL PRINCE WILLIAM AND SOUTHERN FAIRFAX COUNTIES UNTIL 5:45 PM. LOCATIONS IMPACTED LAKE RIDGE... BURKE... LORTON...NEWINGTON... SPRINGFIELD... THE I395 AND I495 INTERCHANGE... FRANCONIA...