From the ABC 7 Weather team

Archive for April 2013

World Record High Temperature Recently Struck Down

April 14, 2013 - 05:47 PM
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It has been written in many textbooks and given credibility for the last 90 years but now a panel of experts from the World Meteorological Organization has invalidated the world record high temperature set in Africa.

Northwestern Libya is subjected to offshore breezes that compress and warm off the Jabal Nafusah mountains. The wind is further heated as it travels toward Tripoli, Libya’s capital city. As a matter of fact, a day with this weather in place on September 13, 1922 led to the observation of 136 degrees just outside of Tripoli in a town called El Azizia. An apparent severe thunderstorm well south of El Azizia produced a strong wind gust that ended up downsloping off the mountains and sent the temperature soaring once the gust arrived in the town.

 

Libya
After extensive research from that event and a look at atmospheric pressure data and sea surface temperatures from this area in Africa, the unusually hot temperature was questioned. The analysis concludes the corresponding air temperature in northern Libya was about 87.8 degrees.

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Back Door Cold Front: What the Heck is That?

April 11, 2013 - 10:09 PM
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Anyone outside tonight noticed the cool air coming in as temperatures dropped 25° in a few hours.  A cold front came through . . .but through the back door.  What is the back door?  Our weather and cold air ususally moves from west to east or north to south as shown in this map of the jet stream for Saturday. 

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Most cold or cool fronts come from west to east. . . the front door as seen in this radar image of strong storms moving through Ohio and coming our way for Friday. 

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But this evening some cool ocean air moved in from the east . . .the back door and look at this great image.  Our interactive radar and temperature map showed the dramatic range of temperatures.  

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The cool air is more dense than warm air and the front was probably pushing pollen and even insects west and the line of the backdoor front shows very clearly on radar. 

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No rain with this back door the rain come Friday with the front door.  But does lead to a delightful weekend.

 

 

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Wet Friday morning commute in the D.C. area

April 11, 2013 - 02:57 PM
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LIVE DOPPLER RADARHD WEATHER CAMS 

A strong cold frontal boundary will move through the D.C. area tonight into tomorrow morning. Heavy rain will be possible along with embedded thunderstorms through the early morning hours continuing through the morning commute. That being said, Friday shouldn't be a complete washout, with sunshine returning by the afternoon and evening and staying in time for the weekend.

Timing the Rain

Rain should begin in the early morning hours closer to 3am in the D.C. area and continue to be heavy at times through 8am or 9am. Pockets of showers will continue to be possible through lunch time, but partial clearing should take place through the afternoon. Here is a look at our in-house microcast at 7am depicting a line of heavy showers and storms.

Microcast Forecast for Friday at 7am

How much rain should you expect? We are thinking rainfall totals will be on the order of a half of an inch to an inch. The WPC's QPF forecast shows this as well, with some localized areas of over an inch possible in parts of the D.C. area.

WPC QPF Forecast for Thursday through Friday

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April Warm Spell Continues: Any Record Heat?

April 10, 2013 - 05:00 AM
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It feels like we completely skipped the spring season with 50 degree high temperatures last week (average for late February) and 80 degree highs this week (average for early June).  Where's spring??

Spring is taking a little hiatus, but will return by the weekend.  In the mean time, high temperatures climbed to the 80 degree mark in Washington on Monday, which was the first 80 degree day, since October 24, 2012.  Yesterday, all of the region made it into the 80s with Reagan's high 86°.

Highs Tuesday April 9th

No records have been reached.... yet.  Today will be the hottest day this week and records are likely to be tied or broken.  In fact, I can almost guarantee Dulles will record a record.  The current record is 78° set back in 1992.  DCA and BWI's current record is 89° from 1922.

So how did it go from winter to summer in such a short period of time?  Well, it's all the position of the jet stream.  Last week, the polar jet was positioned very far south, which allowed cooler than average temperatures across much of the US.  This week, however, the jet stream is well north of Washington (over the Great Lakes and northern New England), but took a big dip in the west.  Check out the highs yesterday.  I drew a blue arrow to delineate the jet stream.

An area of high pressure off the Atlantic coast is bringing winds out of the southwest and pumping in the warm temperatures from the south.  The high has also kept the weather sunny.  A completely different story for folks out west. 

Surface Analysis for Wednesday, April 10

A strengthening area of low pressure over the south central Plains, in association with the diving jet stream is bringing a combination of snow and severe weather to the Plains.  The sharp contrast in temperatures along the front is causing very active weather.  In fact, some spots (Oklahoma City, for example) were under severe thunderstorm watches and winter weather advisories at the same time!  Check out the radar from yesterday evening.  Severe storms were firing up in parts of Oklahoma, Kansas, and Nebraska, but snow was falling in western parts of those states, too.

No sign of snow or wintry weather here, but the cooler weather will filter in for the weekend.  It won't be anywhere near the cold, single digit temperatures out west, but it will be a good 20 degrees cooler than temperatures today.  With highs in the middle 60s both Saturday and Sunday, it will be average April weather in Washington... go figure!

 

 

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Cherry blossom photography tips (Guest blog)

April 9, 2013 - 01:09 PM
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You know it’s cherry blossom season when the cold air turns warm and hundreds of tourists start making their way to the nation’s capitol. It can be a little intimidating with the crowds of people all around, but as long as you use these helpful tips, you’re sure to walk away with some great shots!

Camera Settings
In case people walk in front of your shot, or the cherry blossoms are blowing in the wind, you’ll want to set you camera settings so it takes pictures really fast. For this, I’d increase your ISO (depending on the time of day, I’ve set my ISO to 1200 close to dusk) and your shutter speed to a fast setting.

Time of day
My favorite time of the day to shoot is during sunrise and sunset. Not only is the sun low, which light up the blossoms, but you’ll sometimes get these beautiful colors in the sky that you don’t see in the middle of the day. Clouds can also add interest to your image.

Credit: AB Pan Photography

Practice your Compositions
There are a few composition techniques that may help you create a more interesting picture.

Credit: AB Pan Photography

Natural framing - use the cherry blossom branches to frame your point of interest

Rule of thirds - Pretend there is a tic-tac-toe board on top of your images. Place the focal point at one of the intersecting points instead of dead center

Leading lines - When someone views your photo, they are naturally drawn to lines. Think about how you can direct someone’s eye around your photo using lines. 

Keep on moving
It’s easy for photographers to find the perfect spot with the perfect composition and just stand there for hours. I suggest to take your shot and keep walking around or else you’ll go home with a memory card full of the same image.

Look up!
So many of us walk around looking straight ahead or down. Look up! You’ll definitely get some great shots of the blooms in a perspective you may have never thought about before. 

Credit: AB Pan Photography

The tidal basin isn’t the only place to take cherry blossom pics.
Take the opportunity to explore the city. You’ll find that there are a lot of great places to take photos such as the National Arboretum, National Cathedral or even Meadowlark Botanical Gardens in Vienna, VA.

But above all else...be patient
Tourists, other photographers, runners, picnickers, bicyclists, etc. all have the potential of getting in your way. The best thing to do is remember why everyone is there: to enjoy the beauty of the cherry blossoms. Don’t get upset at someone for being in the way because when it comes down to it, you’re probably in someone else’s way too.

About the Author

Angela was born and raised in the D.C. area and graduated from Langley High School in Northern Virginia. She is an award-winning travel photographer whose work has been featured on ABC, TravelChannel.com, and the Washington Post. Her blog has been named one of the top 100 travel blogs and has been internationally recognized by the World Journal.

See her prints for sale here

Follow her: Facebook  |  Twitter

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80° days: Recency and decisions

April 8, 2013 - 05:01 PM
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Today was our first 80° day of the year. Just about spot on to our "average" date of the first 80° day which is April 7th.   Our poll on when you thought the first 80° would happen has been up since very late March.  Look at the poll from Saturday before a confident forecast of 80°.

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The climatological average high May 31 is 80.  But more than 10% thought the first 80° day would happen even later than the date with an average high of 80°. .  So why did so many of us (90% of us) think or guess the first 80° WOULD NOT happen in the first week of April?  I think it has to do with something scientists and psychologists who study behavior call "recency bias" .  A bias due to recent observations.  The bias or tendency to place more emphasis on recent events than events in the more distant past.  March 2013 was much cooler than average, 13° colder than the record warm March 2012.  March 2013 didn't even have a single 70° day and ended with a very chilly pattern.  This pattern would sure continue based on recent history . . .recency bias.  Some of us probably thought the first 80° day wouldn't come until late May or June after the weather pattern we experienced this March.  We really have to be careful of this recency bias in making weather related decisions during dangerous weather.  A tornado, flash flood, damaging winds haven't happened here recently (or ever in a lifetime) so it won't happen.   Tip our poll on the side and it is a little bit similar to a "normal" distribution.  

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That is a distribution of responses (were they random guesses?) that peaked around the center and fall off on either side.  

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What if we thought, or guessed, the "correct" answer must be the midpoint of the choices.  Other biases (such as conformation bias) sure enter our thinking.  But that's how we (scientists are human also) think about issues such as climate change, social issues, and political commentary.  Try not to be too biased : >) Next year we'll try again.

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Cherry Blossom Update (Monday evening)

April 8, 2013 - 05:00 PM
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Monday evening bloom update:  After a high of 80° at Reagan National, the cherry blossoms are blooming quick.  A noticeable difference from yesterday with much more 'white' seen along the National Mall.  After another mild night tonight and warm day tomorrow, the Stormwatch 7 weather team feels confident the cherry blossoms will be at their peak by Wednesday and Thursday. 

What perfect timing, too!  The forecast for the next few days is almost summer-like.  Partly cloudy skies, breezy southwesterly winds, and highs well above average are expected through Thursday.  Changes arrive late Thursday into Friday, as a cold front slides through, so now's the time to check out the beautiful blossoms!

 

Monday morning update: The forecast for the peak bloom of the Cherry Blossoms has been delayed twice already and if you were like me and headed to the festival this weekend, you may have been a little bummed.  This is what the majority of trees looked like on Sunday afternoon.   



Sunday Afternoon

 
  There were 2 or 3 trees that were in full bloom and looked like this.    



A Few Trees Peaking


You can imagine that there were a bunch of people crowded around those few trees and were taking pictures.  The National Parks Service was expecting peak late last week.  By my estimation, it stands at about 20%.  If you look at this photo of the MLK Memorial, you can see the light pink starting up. 



Estimating 20% in Bloom

 
That's what the majority of the area looked like, still pretty.  The weather was beautiful, so it was still an enjoyable time.  We hit a high of 71 degrees on Sunday.  It did feel a little cooler with the brisk winds (and made it a bit tough getting my family's paddle boat back at the dock!).  I am not a Cherry Blossom expert and I am not an Arborist.  But, based on what I know about the warm weather this week (80s on Wednesday!), and the research that I've done, I have made a prediction that peak bloom is about 4 days out or so...  Peak bloom is when trees have 70% of the flowers open. 



Petal Prediction

 
But, there is a bit of a hiccup if you want to go on day number 4 which is Friday.  Rain is on the way.  A strong cold front will bring thunderstorms Thursday afternoon/evening and then end with rain on Friday morning with cooler temperatures to follow. Check out the 7day forecast here.  If our winds get strong enough in those thunderstorms, that could bring down quite a few petals.  So, if we look at the combination of nice weather and best opportunity to see the most petals, Wednesday may be the best day.  As always, we love to share your photos.  Keep them coming to www.wjla.com  

 

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How the Seasons Received their Names

April 6, 2013 - 11:30 AM
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Have you ever wondered why “summer” is called summer or “winter” is referred to as “winter”? No? Me either. Until I had inspiration from my next blog post from my colleague’s Adam Caskey’s 4 year old son. He asked “why does Fall/Autumn have two names when other seasons do not?” That got me thinking, why ARE the seasons named what they are and what is the rhyme or reasoning behind it. Having studied Latin in high school, I figured most were derivations from the Latin language and this was going to be a super simple-wham-bam done type of blog post. However, once I started reading about the seasons and how they received their names, I knew I was waaaaay in over my head in writing this blog. Old English, Middle English, German, Old Norse, Swedish, Gothic, Indo-European, Irish, Welsh, Sanskrit (Insert PCU quote:

                                                                                    

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Droz: "What's Your major?"

Sanskrit Major: "Sanskrit"

Droz: "Sanskrit. You are majoring in a 5,000-year-old, dead language?"

Sanskrit Major: "Yeah."                                                          

Droz: (hand Sanskrit Major Latin paper thesis) "Hmmm... Latin, best I can do".

...continuing on with the blog -- Old Irish, Lithuanian, Modern Livonian (a Finno-Ugrian language)—Yup, got me too—It just got exhausting. Then, I started wondering “well how did we even GET to four seasons?” Once I started my research I realized that most locations orginally operated on a two-season system. Great. Awesome. No turning back now and being a scientist, the question is always “why?”—Sometimes I wish I would just stop at the first “why” and leave it at that.

Well back to the FOUR seasons and why-The earliest indicator seems to be among the Greeks, Antiochus of Athens- a Hellenistic astrologer in the late first to early second centuries A.D. He relates the four seasons to colors, elements, directions, times of life, humors and temperaments (Table 1). His findings became some of the first of scientific learning in medieval times and beyond.

Table 1:

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The Roman’s then jumped on board the whole “four season” bandwagon a used the color symbolism with the seasons and associated that with the horse races in the Coliseum. For example: Roman charioteer’s horses were originally dressed in two colors, white (winter) and summer (red). Later on green (Spring) and blue (Fall/Autumn) were added (obviously different colors than what old boy Antiochus of Athens described above-go figure).

Okay, so here we go:

Starting with Winter. Winter is the most prominent of the Old English seasonal terms since it was a figure of speech determining “a year”. Winter is used six times to describe “1 year” in “The Phoenix” and ten times in “Beowulf,” thirty-six times in “Genesis A. Then as time went by, Winter became a metaphor for “adversity” due to the weather associated with it (as we all know this late winter of 2013). Shakespeare’s sonnet 56 ends with the couplet, “Else call it winter, which being full of care/ Makes summer’s welcome thrice more wish’d, more rare.”

Germanic dialects developed a new word, Sumer—influenced by Celtic *sam (or sem, or sum in Latin meaning “half") and Gothic, the wet season…added the addition of –er (now SumER and WintER instead of Wintrus). Like Sumer literally “half-year.” Sumer or summer is defined in the Middle English Dictionary as 1. The warmest of the four season of the year 2. The warm half of the year, the half of the year during which the days are long—usually used in contrast to winter.

The story “Beowulf” also mentions “summer” using a derivation of its Old English spelling of “gear” where winter gives way to “gear in geardas” or “summer in the courtyards.” (1132b, 1134a) as well as in the poem Guthlac A (1 out of a pair of poems written in celebration of the deeds and death of Saint Guthlac, a popular Mercian saint written sometime between 730 and 740 AD) where with the “sele niwe” (new season) the fields blossomed and “geacas gear budon” (cuckoos announced the summer). “gear” was used in the broader sense to incorporate both Spring and Summer. Just as “winter” is a term to describe adversity, Summer became a term to symbolize “pleasantness.” Now this is the Old English meanings of Winter and Summer – Chinese culture seems to be the completely opposite with Spring meaning “pleasantness” and Autumn meaning “adversity.” But please, I am sure I have bored you enough—I’m not going to touch that.

Okay so I have ONE person still reading this.....now moving on to those other secondary seasons: Fall/Autumn and Spring. Lencten (Old English = Lencten or Middle English = Lenten) was widely used to refer to as “spring” and relates to the season when days begin to lengthen. Lencten does not mean springtime exclusively…..most of the earliest writings, starting after 1275, the meaning is clearly “lent.” However, as time went by, Lencten began and continued to be referred to as springtime as well as Lent as late as the 14th century. However, spring is first recorded as a season word in 1483 by the Catholics meaning "to spring up" as plants tend to do. However as you can see below (Fig. 2*), English went without a word for the season of "spring" for over a century although there were several substitutes over the years (Fig. 3*) there was never one that was clearly decided on and most were short-lived. However, "spring" seemed to be the common denominator Now, just like Autumn and Fall and earlier “Gear” and “Sumer”—it seems that for A WHILE Lent and Lenten (and some even argue "spring--although not in English language) were synonymous and had a period of overlap.

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Now, just like Autumn and Fall and earlier “Gear” and “Sumer”—it seems that for AWHILE Lent and Lenten (and some even argue "spring" in various forms) were synonymous and had a period of overlap. Eukera! There we have the answer! Not JUST Autumn and Fall, but Summer AND Spring had synonyms at a point in history. Glad we cleared that up!



Stay with me now, heading on to the last and most complicated naming of the season—Fall or autumn or is it “harvest”?….Well "Harvest" never really seemed to catch on. German’s wrote “autumni” (derived from the Latin word autumnus) which means “harvest” and refers to the agricultural period when crops are taken in, rather than to a season (Fig 4).

Fig. 4

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"Autumn" first appears as English word in the late 14th century and was popular with Anglo-Saxon and Early Middle English times. "Autumn" and "Harvest" seemed to coexist as synonyms through the 17th century. "Harvest" coexisted with autumn beginning in the late 15th century but was lost by the 18th century as people gradually moved from working the land to living in towns (Fig. 5).

 Fig. 5

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Fall first appeared in the 17th century but by the 19th century was marginalized as an Americanism. .The exact derivation of “Fall” is unclear however, with the Old English “fiaell or feallan” and the Old Norse “fall” are all possible candidates as all these words have the meaning “to fall from height”. During the 17th century as the English began the emigration to the British colonies in North America, the new settlers took the term “fall” with them. This became the more common term in North America while “Autumn” continued to be the term of the season in Britain.

 

Whew, so if you made it through all that, not bored out of your mind-you now know more than you EVER needed to know about Sumer (or is it "Summer) and Winter/Wintrus-the primary seasons, and Fall/Harvest/Autumn and Spring/Lecten/Lent/Ver, the secondary seasons....exhausting.

*I could have not written this article without the following references:

-"Meaning and Beyond" by Ernst Leisi Zum (Fig. 2,3,4,5),

-"Folk Taxonomies in Early English" by Earl R. Anderson (Table 1)

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Weather: At your fingertips

April 4, 2013 - 11:30 PM
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OK after quite a bit of work and development... it's here.  One of the coolest smartphone weather apps around and certainly the coolest and most personal for the Washington area.  Here's where to get it for your iPhone  and for your Android phone.  You get to see our local Super Doppler. 

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You can also see the the regional radar and see where the heaviest rain or storms are moving.  Check out this cool interactive hour by hour forecast to see tomorrow will be 60 even with the cold rain tonight. 

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 Our local personal forecast, blogs and more.  

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Nothing like it here...and more features to come.  Give it a try and let us know what you think.  Best of all. . . .it's free!!!

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The Deadliest Outbreak of Tornadoes-An Inside Look

April 4, 2013 - 10:36 AM
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Today and yesterday mark the anniversary of one of the deadliest outbreaks of tornado activity in the history of the United States. In just an 18 hour period from April 3rd and 4th of 1974, a deadly outbreak of severe weather spawn across 13 states including Alabama, Georgia, Illinois, Indiana, Kentucky, Michigan, Mississippi, North Carolina, Ohio, South Carolina, Tennessee, Virginia and West Virginia producing tornado damage of about 900 square miles (Fig 1 & 2).

Fig: 1 ( Courtesy: TornadoHistoryProject)

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Fig. 2 (Courtesy of NOAA)

 

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The US experienced around 148* tornadoes with half being a F2 on the Fujita scale, and monster tornadoes, 24* F4’s and 6* F5’s (fig. 3) or higher, to have a combined path of 2598 miles and 1881 of those tornadoes had paths over 1 mile long. By the end, ten out of the thirteen states hit were declared disaster areas killing 335* people and injuring over 6000.

Fig. 3rd (below shows the Fujita Scale which was incorporated in 1971 and later validated by its importance by Ted Fujita and his colleagues after the 1974 Super Outbreak--the scale was later revised February 1st, 2007).

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About 1,200 tornadoes hit the US each year and tornadoes kill on average about 60 people per year, mostly from flying/falling debris. From this particular event, over 15,000 homes, farms and business were destroyed and another 17,000 building were damaged. Of those that died, 74% were killed while in houses or buildings, 17% in mobile homes, 6% in automobiles and 3% while seeking shelter.

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F5 tornado in Xenia, Ohio April 3, 1974 (Fred Stewart, NOAA)

 

 

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 (Destruction in Northfield, Kentucky. Courtesy of Russ Conger/NWS)

  

It all began on the afternoon of April 1st when in the upper levels off the coast of northern California and Oregon, a strong baroclinic wave was detected. This with an associated cold front moving through Nevada and Idaho would later produce extremely severe weather over the eastern US.
It seemed the days leading up to the Super Outbreak of April 1974, the ingredients were just right and falling into place for a major weather event across the south and eastern portions of the United States. As the wave was moving inland from the Pacific, low level cyclogenesis was occurring over the Great Basin and Southern Rockies. This wave moved to the east-southeast and along with a strong polar jet this wave amplified. On the evening of April 2nd, the surface low strengthened east of the Rocky Mountains and continued its eastward movement across the United States picking up moist and warm air from the Gulf of Mexico clashing with an upper level layer of warm dry air from the southwestern states. The central pressure of this low was 983 mb (Hurricane Sandy central pressure was 946 mb at landfall along the coast of Southern New Jersey and Hurricane Katrina was at 902 mb at its most intense-920 mb at its second landfall in Buras-Triumph, Louisana) and the circulation of this low was approximately 1200 miles in diameter. The moist air continued to stream from the low toward the OH Valley and the lower Midwest states. So with a strong upper level jet, the moist air at the surface and the dry air in the upper levels, a large region of subsidence formed (where the dry air was sinking onto the lower moist air which acts like a lid, keeping the moist air from rising and dissipating energy) meaning that conditions were quickly becoming unstable and favorable for a severe weather event. This increased even more the morning of April 3rd as the sun began to continue to add energy to an already extremely dangerous atmospheric situation. So with the area of low pressure marching eastward across the US, the Gulf providing warm moist surface air, dry air in the upper level, subsidence occurring because of this and then solar heating?-->Large severe weather outbreak stretching over thirteen states and a portion of Canada.

(Below: April 3rd 1974 3:11PM EST)

 

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(Below: April 3rd, 5:54 PM EST)

 

 

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(Below: April 3rd, 9:00 PM EST)

 

 

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However, a advance in technology that was desperately needed came with this outbreak. At the time, forecasters at the National weather service had to wait for visual confirmation of tornadoes before issuing any sort of warning which were all made my hand and sent over by a teletype machine (Fig. 4 & 5)

Fig. 4- a gentleman by the name of Pat Iannelli prepares to transmit a forecast through the teletype machine in Parkersburg, WV. During the outbreak of 1974, weather offices continued to experience slow reaction time with these machines due to the high volume of traffic during the event)

 

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Below Fig. 5 - Teletype machines lined up in the Fort Wayne NWS office at Baer Field, June 1967. They were installed April 18, 1961. Facsimile machines to receive weather maps were installed April 1, 1960.

 

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 Fig 6: Main workstation at NWS Fort Wayne in July 1968.

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Radar was only adept to pick up green blobs that was better suited to picking up solid objects as opposed to clouds and rain and very few television stations had radar-and most that did were in black and white (Fig 6). 

Fig. 6 shows a hook pattern in the radar which is synonymous with severe weather, possibly a tornado.

 

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With the historical events of April 3rd and 4th of 1974, advances in radar were made with NEXRAD and Doppler Radar-the same technology that we use today, with improvements every year. The current average lead-time for tornadoes has now been increased to 13 minutes.


*In my research, I have seen differing information on the number of recorded tornadoes (give or take 1 or 2) as well as the number of fatalities. This is evident in my numbers and graphics. Nonetheless, even with these varying factors, this outbreak without a doubt continues to be recorded as one of the deadliest outbreaks in American History.

 

 


 



 

 

 

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April: Wacky spring month in Washington

April 4, 2013 - 05:27 AM
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As April begins, thoughts of warm weather and spring come to mind. However, wacky weather has been known to strike the Washington area in this month. While the month is getting off to a cold start with temperature 2 degrees below average, rain is needed to curb the 2 inch precipitation deficit. Speaking of rainfall deficit, this is also the month where warmer winds combined with low relative humidity and a quickly drying ground (when precipitation is scarce) can lead to wildfire danger.

Already on Wednesday, a Red Flag Warning was posted for the region due to the combination of these factors. Due to the delayed start of the growing season compliments of the recent cold spell, the sun is able to penetrate the forest floor and dry the top soil out quickly. When the wind blows strongly across the ground and dries the air and soil, forest fire danger quickly becomes a problem. Low relative humidity is exasperated by lack of vegetation because leaves and such give off water vapor (evapotranspiration) and act as a humidifier in the summer. This will be a problem during dry, windy periods in April as the leaves, grasses and plant life get a late start this year.

Besides the winds, April can bring excessive heat, numbing cold, spring deluges and flooding as well as late-season robin snow. Here’s a look at the extreme weather in Washington during the month of April.

April_Extremes

In addition, it’s important to keep in mind the sun will get higher in the sky. As a matter of fact, the sun angle is comparable to that seen in August. Just because temperatures may be cool, the higher sun angle can equate to sunburn in a short period of time, especially those who are fair-skinned.

The image below shows how the sun angle compares to other times of the year. The April sun angle is the same as the August sun angle and the May sun similar to the July sun angle, etc. (Note the horizontal arrows showing this).

 

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The official Climate Prediction Center forecast calls for a good probability of warmer than average temperatures in the East. Click here for the details.

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TIROS-1: 53 Years of Satellite Meteorology

April 3, 2013 - 05:00 AM
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Satellite images are used on a day-to-day basis.  Check out this great AQUA satellite image from yesterday!  The high resolution picks up the very few clouds across the region.

NASA Aqua

Not only do these weather satellites show us where clouds are, but they also can track changes in weather patterns, severe weather, tropical systems, and even monitor climate changes.  The evolving science and technology in weather satellites has come very far from when the first operational satellite was launched in 1960. 

TIROS-1 (Television and Infrared Observation Satellite) was launched 53 years ago on April 1st, 1960.  It was a historic day for weather forecasting, since it was the first satellite designed to obtain cloud pictures to observe Earth's weather conditions on a regular basis.  TIROS-1 rocketed into space from Cape Canaveral, Florida early that April morning. 

NASA

The first image captured by TIROS-1 was a fuzzy picture of clouds over the U.S.  Just days later, the TIROS-1 captured images of a typhoon about 1,000 miles East of Australia. 

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NASA Administrator Charles F. Bolden, Jr. stated "TIROS-1 started the satellite observations and interagency collaborations that produced vast improvements in weather forecasts.  It also laid the foundation for our current global view of Earth that underlies all of climate research and the field of Earth system science." 

More advanced series of TIROS satellites were launched between 1978 and 1981 and were then called POES (Polar-orbiting Environmental Satellites).  POES orbit the Earth at an altitutde of about 500 miles and circle the poles once ever 102 minutes.   It's incredible to see how much has changed in a span of four decades.

NASA

NOAA and NASA are now working together to launch the next generation of satellites, which will only help further the advancements in weather forecasting and research. 

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Tornadoes and Sequesters

April 2, 2013 - 05:00 AM
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OK, I admit the title was meant to get your attention. The automatic federal spend cuts (the “sequester) has been felt by almost every part of the government. Some, but sure not all, may have been needed. If we agree that one of the fundamental functions of any government is the protection of the citizens life and property, these 'across the board' cuts may be risking lives. One vital government agency that works every day to protect life and property is our National Weather Service. Can we afford cuts that may decrease the accuracy and timeliness of tornado warnings, flood warnings, reduce the accuracy of storms and hurricanes? Cuts that may weaken the core heart and structure of the great advance we have made as a scientific community and country in serving our citizens and country? Marshall Sheppard, a leading researcher and President of the American Meteorological Society, wrote this article about the risks we face heading down this slippery sequester road for our nation’s weather and climate services. I agree.  -- Bob Ryan

NOAA Hiring Freezes, Travel Restrictions: Not Alarmist Just Reality-Our Weather Forecast Can Get Worse and Jeopardize US Public

This week NOAA, also the parent agency for the National Weather Service (NWS), announced a hiring freeze at a time when its vacancy rate is already around 10%. I understand that this number is near 20% for the Washington DC area NWS Office. At this point, pause and consider public safety. As we enter the severe weather/tornado seasons, the Sequester has forced the hand of our NOAA management and possibly jeopardized the American public's safety, stifled scientific capacity, obliterated morale within NOAA/NWS, and dampened hopes for the next generation of federal meteorological workforce. Beyond safety, we have increasingly clear evidence that weather is important to our economy (see commentary by me and Nancy Colleton on the "next Commerce Secretary" at http://www.huffingtonpost.com/nancy-colleton/the-next-secretary-commerce_b_2807671.html). Now to be clear, I know, personally, the senior level managers at NOAA/NWS very well. I know they will do everything within their power to adjust and mitigate impact. This commentary is really not about them.

It is simply important to understand that NOAA/NWS functions are public services vital to the Nation. Like our dedicated military, border patrol agents, police officers, and firefighters, NOAA employees are providing a service that affects our lives every day, including warnings and alerts. A community would be outraged at cuts to a Fire Station station staff near them, particularly at a time when a rash of arson incidents were happening. I hope you get the point I am making. Additionally, NOAA/NWS personnel are increasingly missing as subject matter experts for major Emergency Management training and conferences.

NOAA

Further, the vibrant and critical private weather enterprise adds value based on data, models, and warnings that come from the weather service. To elucidate the federal-private relationship, I have often joked that NOAA is to the private sector weather enterprise, what the potato farmer is to a company that makes French Fries. It is a vital partnership, which includes research and applications from academic partners as well. The American Meteorological Society's Washington Forum will bring together the sectors for a vital discussion next week (http://www.ametsoc.org/meet/fainst/2013washingtonforum.html) Additionally, ongoing discussions about a Weather Commission are increasingly important (http://weathercoalition.org/).

I am fearful of what is happening in our community with draconian sequester cuts, challenges to travel/science meeting attendance (I spoke on this last week in a blog at the AMS Front Page, http://blog.ametsoc.org/columnists/for-science-and-discovery-videoconferencing-wont-get-it/), and other stresses on science/R&D support within the National Weather Service/NOAA (journal publications, fees, etc). If you couple this with looming concerns about weather satellite gaps, computing capacity to support advanced modeling, and employee morale, we are slipping down a slippery slope of "eroding" the U.S. federal weather enterprise. However, since industry, academia, and federal agencies work closely together, these effects will ripple throughout the broader community.

NOAA Computer Models - Supercomputers

During a recent interview on CNN, today's interview, I discussed the Arctic Oscillation, Blocking Highs, and a high resolution RPM model forecast. The knowledge and capabilities related to these discussions emerged from years of research, development, collaborative sharing via meetings, and investments. The public may take for granted a tornado warning (probably from a Doppler indicated signature) or satellite loop of an approaching hurricane. Likewise, the public probably just assumes that they will have 5-9 day warning of storms like Sandy; 15-60 minutes lead time for tornadic storms approaching their home; an airline with appropriate data for safe air travel; or a military with reliable information to avoid hazardous weather on a mission protecting our freedom. However, these capabilities "can" and "will" worsen/degrade if we cut weather balloon launches, cut investments in the latest computing technology for our models, reduce Doppler radar maintenance, delay satellite launches, or shatter employee morale. We are accustom to progress, innovation, and advancement and have come to expect it. I am honestly concerned that we will regress in capability and this will jeopardize lives, property, and our security. Anyone that knows me, understands that I am not an "over-the-top," hyperbolic person. I just call things as I see them. And by the way, I have not even spoken about the challenges that a changing climate adds to the weather mix.

NOAA

As a Professor of Geography (http://geography.uga.edu/) and Director of University of Georgia's Atmospheric Sciences Program (http://atsc.uga.edu/), I see young, vibrant, and talented students everyday that embody the next generation weather enterprise. They are taking notice of what is happening, and I believe this seriously jeopardizes our future workforce.

As we enter the active spring tornado season, let's hope the sequester season ends, before the hurricane season begins.

End Note: I am aware of the challenges related to travel and emissions. Three points are worth noting: 1. AMS has a Green Meetings initiatives (http://www.ametsoc.org/meet/greenconferenceguidelines.html), 2. Large shifts to videoconferencing are not completely immune as energy is still required to support increased computing/IT requirements for these activities, and 3. Videoconferencing may be highly appropriate for smaller committee and board type meetings but not large scientific meetings, which was the point of my aforementioned blog on the Front Page.

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Amazing Timelapse of Morning Fog over D.C.

April 1, 2013 - 03:19 PM
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The early morning Monday fog may have slowed you down on the roads, but here's an incredible perspective! 

Our WeatherBug camera, atop our studio in Arlington, captured this fantastic timelpase of the fog over the city.  If it weren't for the Washington monument, it may have been hard to distinguish where the camera was located.  The low clouds blanketed the city and it almost looked like the view from an airplane flying high over the clouds.  Enjoy!

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April averages ... What will this month bring for D.C?

April 1, 2013 - 08:42 AM
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Navin Sarma Photography

April showers bring May flowers ... You know the saying. April is a month of transition when temperatures warm up and spring rain and thunderstorms help to green us up. March was a cooler than average month for the D.C. area this year, and the first week of April will be that way as well. The average high for April 1st is 62 degrees. By the end of the month, our average high jumps to 71. 



April Averages

 

The hottest April temperature was 95 degrees recorded four different times. The coldest April low was only 15 degrees. Brrr! And, yes... we have had snow in April before. In fact, on April 1, 1924, Reagan National recorded 5.5” of snow (more than we have had all season!). The latest April snow happened on April 28th. As for the April showers, we average 3.06” of rain for the month. The wettest April happened in 1889 when D.C. received more than 9 inches of rain. That was the year of The Great Flood. Check out this picture of a flooded Pennsylvania Avenue from the Library of Congress: 



Great Flood of 1889-Library of Congress

 

While D.C. should be near average for temperatures today, the rest of the week looks cooler than average. Spring-like temps return this weekend. NOAA’s spring outlook has the Mid-Atlantic with above average temperatures and no major river flooding expected.

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Nats Opening Day Washington D.C.Forecast

April 1, 2013 - 05:01 AM
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Foggy morning at Nats Park

The defending NL East Champions Washington Nationals take the field vs. the Miami Marlins at Nats Park today to kick-off another season of baseball. From cold and snow to sun and warmth, anything can happen during spring baseball, so here's your Natscast to prepare you for the game.

 



Natscast

 

First and foremost, temperatures will be agreeable in 60s. A cold front will push toward Nats Park during the game today, and this will increase the clouds for a few hours. This front should have just enough kick to generate a few raindrops, so we can't rule out a stray sprinkle (20% chance) by the second half of the game. However, this would be extremely light and probably not even enough to chase fans into the concourse.  Enjoy the game and Go Nats!!

Look who just showed up to the ballpark!  He's fresh off spring training and ready to race!



Teddy

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