07/30/2015

VIDEO: The Rare "Blue Moon" Occurs Tonight! But what does that mean???

When someone says "Once in a Blue Moon," you know what they mean: Rare, seldom, even absurd.

This year it means "the end of July."

For the second time this month, the Moon is about to become full. There was one full Moon on July 2nd, and now a second is coming on July 31st. According to modern folklore, whenever there are two full Moons in a calendar month, the second one is "blue." 

 

This definition of a Blue Moon is a recent thing.

If you told a person in Shakespeare's day that something happens "once in a Blue Moon" they would attach no astronomical meaning to the statement. Blue moon simply meant rare or absurd, like making a date for "the Twelfth of Never." Since then, however, its meaning has shifted.

The modern definition sprang up in the 1940s. In those days the Maine Farmer's Almanac offered a definition of Blue Moon so convoluted many astronomers struggled to understand it. It involved factors such as ecclesiastical dates of Easter and Lent, tropical years, and the timing of seasons according to the dynamical mean sun. Aiming to explain blue moons to the layman, Sky & Telescope published an article in 1946 entitled "Once in a Blue Moon." The author James Hugh Pruett (1886-1955) cited the 1937 Maine almanac and opined that the "second [full moon] in a month, so I interpret it, is called Blue Moon."

This was not correct, but at least it could be understood. And thus the modern Blue Moon was born.

Most Blue Moons look pale gray and white, just like the Moon you've seen on any other night. Squeezing a second full Moon into a calendar month doesn't change its color.

Nevertheless, on rare occasions the Moon can turn blue.

A truly-blue Moon usually requires a volcanic eruption. Back in 1883, for example, people saw blue moons almost every night after the Indonesian volcano Krakatoa exploded with the force of a 100-megaton nuclear bomb. Plumes of ash rose to the very top of Earth's atmosphere, and the Moon … it turned blue!

Krakatoa's ash was the reason. Some of the plumes were filled with particles 1 micron wide, about the same as the wavelength of red light. Particles of this special size strongly scatter red light, while allowing blue light to pass through. Krakatoa’s clouds thus acted like a blue filter.

People also saw blue-colored Moons in 1983 after the eruption of the El Chichon volcano in Mexico. And there are reports of blue Moons caused by Mt. St. Helens in 1980 and Mount Pinatubo in 1991.

Forest fires can do the same trick. A famous example is the giant muskeg fire of Sept. 1953 in Alberta, Canada. Clouds of smoke containing micron-sized oil droplets produced lavender suns and blue Moons all the way from North America to England. At this time of year, summer wildfires often produce smoke with an abundance of micron-sized particles–just the right size to turn the Moon truly blue.

On the other hand, maybe it will turn red. Often, when the Moon is hanging low, it looks red for the same reason that sunsets are red. The atmosphere is full of aerosols much smaller than the ones injected by volcanoes. These aerosols scatter blue light, while leaving the red behind.

For this reason, red Blue Moons are far more common than blue Blue Moons.

Sounds absurd? Yes, but that's what a Blue Moon is all about. Step outside at sunset on July 31st, look east, and see what color presents itself. 

Video and Information Courtesy NASA

WDRB Meteorologist Jeremy Kappell

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The ISS is set to cross our sky this evening!

The International Space Station (ISS) will be making a pass over head this evening.  

At a blazing speed of 17,500 mph, it will cross our sky in about 6 minutes total time making it one of the longer crossings that you will see. 

Gfx

You will be able to view it rise over the SSW horizon at approximately 10:17 pm ET this evening.  It will appear as the brightest object in that part of the sky.  The ISS will move quickly towards the northeast and disappear over the eastern horizon at approximately 10:23 pm.

Unlike many ISS crossings, this one will take it pretty high in the sky rising to about 51° altitude in the sky at around 10:20 pm.

In addition to the space station flyover, we'll also be treated with a near full moon (blue moon) and with a perfectly clear sky in place, viewing should be great!

6a0148c78b79ee970c017c370e8365970bLong Exposure Photograph of the ISS Credit: Mark Humpage

See an amazing time-lapse video taken from the ISS here.

For information on how to photograph the ISS: http://www.universetoday.com/93588/a-beginners-guide-to-photographing-the-international-space-station-iss/#ixzz2Lll4JR00

6a0148c78b79ee970c017c370e8401970b

You can track is progress live here on isstracker.com.

WDRB Meteorologist Jeremy Kappell

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07/29/2015

SPC Highlights Our Area for Severe Potential

The Storm Prediction Center has highlighted much of our area for the possibility of strong thunderstorms this evening.  Full discussion below...

Mcd1571

MESOSCALE DISCUSSION 1571
   NWS STORM PREDICTION CENTER NORMAN OK
   0327 PM CDT WED JUL 29 2015

   AREAS AFFECTED...PORTIONS OF FAR SERN MO...SERN IL...SRN/ERN
   IND...AND WRN KY

   CONCERNING...SEVERE POTENTIAL...WATCH UNLIKELY 

   VALID 292027Z - 292200Z

   PROBABILITY OF WATCH ISSUANCE...20 PERCENT

   SUMMARY...STRONG/GUSTY WINDS WILL BE POSSIBLE WITH SCATTERED
   THUNDERSTORMS DEVELOPING ALONG A COLD FRONT FOR THE NEXT SEVERAL
   HOURS. WW ISSUANCE IS UNLIKELY DUE TO THE MARGINAL NATURE OF THE
   THREAT.

   DISCUSSION...SCATTERED CONVECTIVE DEVELOPMENT HAS OCCURRED OVER THE
   PAST HOUR OR SO ALONG A COLD FRONT MOVING SEWD ACROSS THE
   REGION...POSSIBLY AIDED BY A CONVECTIVELY-INDUCED VORTICITY MAXIMUM
   FROM EARLIER THUNDERSTORMS OVER IA/MO. WHILE NOT PARTICULARLY STRONG
   ATTM...THESE THUNDERSTORMS WILL BE MOVING INTO A QUITE UNSTABLE
   ENVIRONMENT CHARACTERIZED BY MLCAPE OF 2000-4000 J/KG OVER THE NEXT
   SEVERAL HOURS. UNIDIRECTIONAL NWLY FLOW ALOFT IS PRESENT ACROSS THE
   MCD AREA...WITH THE KVWX VWP SAMPLING WINDS OF 20-25 KT BETWEEN 3-6
   KM AGL. ANY SUSTAINED UPDRAFTS ALONG THE FRONT MAY BE CAPABLE OF
   PRODUCING STRONG/GUSTY WINDS THROUGH CONVECTIVE DOWNDRAFT PROCESSES
   GIVEN STEEP LOW-LEVEL LAPSE RATES AND STRONG INSTABILITY AHEAD OF
   THE FRONT. HOWEVER...WEAK BULK SHEAR VALUES COULD LIMIT A MORE
   ORGANIZED WIND THREAT...AND MOST CONVECTIVE ALLOWING MODEL GUIDANCE
   QUICKLY WEAKENS THE ONGOING CONVECTION LATER THIS AFTERNOON WITH THE
   LOSS OF DAYTIME HEATING.

Marc will have a full update on those storm chances on WDRB News this evening.

WDRB Meteorologist Jeremy Kappell

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07/28/2015

The Delta Aquarid Meteor Shower Peaks Tonight! When & Where To Look...

I am a huge fan of meteor showers and I am always excited to tell you of the potential to see meteors shoot across the sky. Tonight, the Delta Aquarid meteor shower will peak in our area and I want to get you the specifics so you know where to look. Here are the details courtesy of NASA article from 2014 with some tweaks I made to apply to 2015...

  

Delta Aquarids

A Delta Aquarid meteor. Credit: Jimmy Westlake
A Delta Aquarid meteor. Credit: Jimmy Westlake

2015 Delta Aquarids Forecast
This year the Delta Aquarids will peak 28-29 July. This year's peak occurs during a near full moon, which is not the ideal situation for viewing. Begin looking for these faint meteors after midnight - 2 am.

Fast Facts

  • Comet of Origin: Unknown, 96P Machholz (suspected)
  • Radiant: Constellation Aquarius
  • Active: 12 July - 23 Aug. 2015
  • Peak Activity: 28-29 July 2015
  • Peak Activity Meteor Count: Approximately 15 - 20 meteors per hour
  • Meteor Velocity: 41 km (25 miles) per second

About the Meteor Shower
The Delta Aquarids are active beginning in mid-July and are visible until late-August. These faint meteors are difficult to spot, and if there is a moon you will not be able to view them. If the moon has set, your best chance to see the Delta Aquarids is when meteor rates rise during the shower's peak at the end of July.

If you are unable to view the Delta Aquarids during their peak, look for them again during the Perseids in August: You will know that you have spotted a Delta Aquarid if the meteor is coming from the direction of the constellation Aquarius -- its radiant will be in the southern part of the sky. The Perseid radiant is in the northern part of the sky.

Viewing Tips
The Delta Aquarids are best viewed in the Southern Hemisphere and southern latitudes of the Northern Hemisphere. Find an area well away from city or street lights. Come prepared with a sleeping bag, blanket or lawn chair. Lie flat on your back and look up, taking in as much of the sky as possible. However, looking halfway between the horizon and the zenith, and 45 degrees from the constellation of Aquarius will improve your chances of viewing the Delta Aquarids. In less than 30 minutes in the dark, your eyes will adapt and you will begin to see meteors. Be patient -- the show will last until dawn, so you have plenty of time to catch a glimpse.

Where Do Meteors Come From?
Meteors come from leftover comet particles and bits from broken asteroids. When comets come around the sun, the dust they emit gradually spreads into a dusty trail around their orbits. Every year the Earth passes through these debris trails, which allows the bits to collide with our atmosphere where they disintegrate to create fiery and colorful streaks in the sky.

The Comet
The pieces of space debris that interact with our atmosphere to create the Delta Aquarids are suspected to originate from comet 96P/Machholz. This short period comet orbits the sun about once every five years.

Comet Machholz was discovered by Donald Machholz in 1986. Comet Machholz's nucleus is 6.4 km ( about 4 miles) across (this is a little more than half the size of the object hypothesized to have led the demise of the dinosaurs).

The Radiant
Their radiant -- the point in the sky from which the Delta Aquarids appear to come from -- is the constellation Aquarius. The third brightest star within this constellation is called Delta. This star and the constellation is also where we get the name for the shower: Delta Aquarids.

 

The bottom line is this not the best meteor shower of the year and tends to be a bit better for locations south of us. To complicate matters a bit, the moon is near full meaning only the bright Delta Aquarid Meteors will be visible. With that said, we have already had reports of fireballs in KY during this meteor shower so it is worth the try especially if you have a pair of binoculars to use. The weather should cooperate with party cloudy skies for most of the night. Here is a look at AdvanceTrak tonight and you can see the partly cloudy skies with low rain chance.

 

AdvanceTrak 1

 

AdvanceTrak 2

 

AdvanceTrak 3

 

In about 1 month, the infamous Perseid meteor shower will occur, so this may be our best shot at meteor viewing of the summer. We will blog about the Perseids as we close in.

 

 

 

Remember it is Summer storm season and if you want to be one of my storm spotters, you can join me on my facebook or twitter page. Just follow the link below and click "like" or "follow".

 

If you ever have any question, please remember I can be reached on facebook or twitter easily! Just follow the link below to my facebook or twitter page and click "LIKE/FOLLOW"!

 

https://www.facebook.com/pages/Marc-Weinberg/171330336238674#!/pages/Marc-Weinberg/171330336238674

 

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Weather Blog: Humidity Drop = Storm Chances

From Jude Redfield...

    Only spotty pop up style storms are in the forecast this afternoon and tonight. Where they hit they hit hard with VERY HEAVY downpours. The risk for severe weather is VERY LOW today.
The cold front arriving late tomorrow gives us the best chance for storms that we'll see over the next 7 days. At this point our storm chance tomorrow looks to be in the 50/50 range.

Bardstown Courthouse

While widespread severe storms aren't expected tomorrow a few could easily reach severe limits. Thankfully wind energy is lacking as the cold front moves by otherwise we would be in for real trouble. Gusty straight-line winds in excess of 50mph and blinding downpours are the main hazards through Wednesday night.

Mesonet

Did someone mention relief? The reason we have storms in the forecast tomorrow is due to the drop in humidity expected. This boundary of jungle-like air meeting up with drier air will be responsible for our 50% chance tomorrow. The payoff could be worth it though as temps become more seasonable for the end of the week. 

TodaysNumbers

07/27/2015

Some Of The Data Shows Strong Storms Later This Week! My Analysis Of The Threat....

By the middle of this work week, we will watch a front move across the area and it will interact with our hot / humid air in place. With all the heat and humidity in the area, it is justified to look and see if any of this could produce severe weather. The Storm Prediction Center does have severe probabilities for our area and that is where we begin the discussion.

 

Storm Prediction Center Severe Weather Risk For Wednesday

 

The Storm Prediction Center (SPC) has their "general t-storm" risk or what they call a marginal risk posted for our area on Wednesday. This is below the slight risk category and therefore we don't show it on TV, but for the blog I will show it here.

 

SPC Categorical Risk Of Severe Weather Wednesday

Notice SPC has their marginal risk for our whole area on Wednesday.

 

Spc 3 cat

 

SPC Probabilistic Risk Of Severe Weather Wednesday

Notice SPC has a 5% chance of severe weather for their marginal risk on Wednesday which is to cover "rogue" severe storms.

 

Spc 3 prob

 

 

My Thoughts On Our Severe Weather Risk On Wednesday

 

To get organized severe weather, we traditionally need specific ingredients present. Since I haven't had the chance to blog a severe risk in a little while, I want to refresh you quickly on the ingredients I look for when assessing whether a severe weather event could occur.

 

Severe Weather Ingredients

 

Forcing

The forcing Wednesday comes from a weak disturbance that moves across the area combined with the weak cold front that will follow. The data shows this weak disturbance late morning to mid afternoon on Wednesday and is enough for us to give it a 50% chance. It is not a monster by any means.

 

Nam_500_vort 1

 

Wind Energy / Instability

Virtually every single day in the summer, we have instability and it will be more than enough to support on severe weather on Wednesday. In tonight's blog, I want to look at the instability and wind energy together to make it a bit easier to digest. For wind energy, we will look at a value called "bulk shear". Basically "bulk shear" needs to be near or above  35 knots / 40 mph to support organized severe weather. With the pattern looking a bit more summer-like, sometimes under ideal circumstances that criteria can flex just a touch. Wednesday, the wind energy is very low at only about 10 knots / 11 mph.  Let's take a closer look.

 

Instability / Wind Energy Wednesday

Notice the instability values are solid and nearly 3,000 units during the afternoon on Wednesday. At the same time, the bulk shear values are struggling near 10 knots or 15 mph. This instability is supportive of severe weather, but the wind energy is sub-standard and would be more supportive of only rogue severe storms.

 

NAM CAPE 1

 

The bottom line is that some of the ingredients are clearly not present in strength on Wednesday.

 

My Thoughts On Severe Weather Chances Wednesday

 

The forcing is not superb on Wednesday, but should be enough to fire some storms. There are questions still about whether the storms go in the morning, then stabilize the afternoon, and minimize the severe threat in the evening.  The evolution of any Tuesday night / early Wednesday storms will need to be resolved in the future data before I can definitively dial this timeline in. The wind energy is borderline pathetic on Wednesday and way below my criteria to support organized severe weather. Let me be clear though, in summer you can still get organized severe storms if the setup is ideal with weak mid level wind flow. There are no questions about whether the instability is supportive of severe weather, but virtually no wind energy is present.

 

How can you get severe weather with one ingredient virtually non-existent? With lots of fuel, sometimes the storms can organized as the cold air rushes out from them causing the line to surge southward. In this scenario, you can get a damaging wind threat with very little wind energy in the atmosphere. I think SPC is doing the right thing keeping this below organized severe weather criteria and going with the general t-storm risk for now . Once we can resolve the timeline for storms, then we can assess if an upgrade to a slight risk would be needed but it is conceivable it will be necessary.

 

AdvanceTrak shows the cluster of storms pop mid afternoon then move southward. Notice the "bow" shape to the storms as they move southward in the afternoon which is a signal for a strong to severe storms capable of damaging winds. This run of advancetrak does support the threat for organized severe weather on Wednesday and we will need to watch it closely.

 

AdvanceTrak 1

 

AdvanceTrak 2

 

AdvanceTrak 3

 

AdvanceTrak 4

 

AdvanceTrak 5

 

 

The bottom line is that some severe could occur in our area on Wednesday. The evolution still has some questions but it seems that a line of strong/severe storms could very well form during the afternoon on Wednesday. Damaging winds and hail would be the main threats.

 

 

 

Remember it is Summer storm season and if you want to be one of my storm spotters, you can join me on my facebook or twitter page. Just follow the link below and click "like" or "follow".

 

If you ever have any question, please remember I can be reached on facebook or twitter easily! Just follow the link below to my facebook or twitter page and click "LIKE/FOLLOW"!

 

https://www.facebook.com/pages/Marc-Weinberg/171330336238674#!/pages/Marc-Weinberg/171330336238674

 

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Weather Blog: Heat Index Outlook

From Jude Redfield...

    *Dewpoint temps above 70 likely through Wednesday*  With the cloud cover and isolated showers this morning allowing for a slow start to the daytime warming we expect the heat index to be the lowest of this wave of heat. Between 3pm-6pm some heat indices will approach 100 today. Wednesday brings in the worst of the heat index with some locations possibly ending up over 105. Heat advisory territory is likely the next couple of afternoons.

Stormview

 

TodaysNumbers

 

**BEWARE OF THE SKEETER METER** Prime conditions over the next few days give us a 5 out of 5 on the skeeter meter.

DropCam

07/26/2015

Lots of Heat, Humidity and the Chance for Storms

It turned out to be a pretty typical late July weekend with lots of humidity and highs in the low 90's both days.  

Temps

With no real push of cooler or drier conditions coming our way real soon, it looks like the heat and humidity will continue to be a factor as we head into the new workweek.  

However, a weak frontal system that has stalled out into Central Illinois and Indiana, will serve as a focus for the possibility of isolated, mainly afternoon/evening, storms over the next few days ahead.  

Satrad

Let's time it out with AdvanceTrak...

Following a mainly dry start to the day, the heat quickly builds into the afternoon on Monday with a few widely scattered afternoon showers or storms.

At1

We see a repeat on Tuesday with temps perhaps going a little warmer.  (I think with stronger ridging aloft, the rain chance may be less on Tuesday than what we will see on Monday)

At2

Although this image of AT looks a bit overdone, we will see the chance for storms increasing by late afternoon on Wednesday.

At3

These storms arrive with a cold front that looks to push through Wednesday night with scattered storms.

Gfx

Behind this front, we'll see some very enjoyable conditions for the end of the week with low humidity and cooler temps.  

Jude will be in with a full update on WDRB in the Morning.

WDRB Meteorologist Jeremy Kappell

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Less Algae, Not Clearer Water, Keeps Tahoe Blue...

Lake Tahoe’s iconic blueness is more strongly related to the lake's algal concentration than to its clarity, according to research in “Tahoe: State of the Lake Report 2015," released today by the Tahoe Environmental Research Center (TERC) of the University of California, Davis. The lower the algal concentration, the bluer the lake.

  Laketahoe20150723-full

Image Credits: Wikimedia Commons

Data from a research buoy in the lake, owned and operated by NASA's Jet Propulsion Laboratory, Pasadena, California, enabled Shohei Watanabe, a postdoctoral researcher at TERC, to create a Blueness Index that quantified Lake Tahoe's color for the first time.

 

The assumption that lake clarity is tied to blueness has driven advocacy and management efforts in the Lake Tahoe Basin for decades. But Watanabe's research showed that at times of the year when the lake's clarity increases, its blueness decreases, and vice versa.

 

Watanabe combined the blueness measurements with data on clarity.  Clarity is measured by observing the depth at which a dinner-plate-sized white disk remains visible when lowered into the water. He was surprised to find that blueness and clarity did not correspond. In fact, they varied in opposite directions.

 

This is due to seasonal interplay among sediment, algae and nutrients in the lake. Clarity is controlled by sediment. Blueness is controlled by algal concentration, which in turn is controlled by the level of nutrients available to the algae.

 

The JPL buoy used in the study is one of four buoys established by NASA with support from TERC to calibrate and validate measurements taken by satellites flying overhead. "This particular buoy has instruments beneath the water looking up and an instrument on the buoy looking down," said JPL's Simon Hook, who collaborated with Watanabe during his research. "The combination of instruments in and above the water was used in this study to look at how light is being scattered and attenuated. That tells you something about both the color and the clarity of the lake."

 

The finding is good news, according to Geoffrey Schladow, director of TERC and a civil engineering professor at UC Davis. “It shows that we better understand how Lake Tahoe works, and it reinforces the importance of controlling nutrient inputs to the lake, whether from the forest, the surrounding lawns or even from the air. It’s particularly encouraging that blueness has been increasing over the last three years.”

 

 

 

-Rick DeLuca

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07/25/2015

Discussing Heat And Storm Chances For The Weekend & Beyond...

The weekend if off to a nice start with a mix of sun and high clouds. Temperatures are quickly warming through the 80's and we should end the day in the low 90's...

12

The first ting you notice when you step outside is the humidity. It was absent the past few days and now it's back. In fact, it will keep rising in the coming days making it feel even hotter...

11

Now that we talked about the heat, let's discuss our storm chances. Today looks completely rain-free. After sunset, a spotty downpour may try to sneak into our far western counties...

Blog 1

Sunday starts off quiet with some extra clouds, then isolated storms develop with daytime heating. Lightning and heavy rain are the main threats with any storm that fires, but MOST of us should end up mainly dry... 

Blog 2

Blog 3

The heat streak continues next week with more 90's and isolated storm chances. Make sure you check in with Kim later today for an update on WDRB. Have a nice weekend!

 

 

-Rick DeLuca

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