Weather Soundings: What are they and how do they work?

You may have often wondered what exactly a weather sounding is. Meteorologists discuss them time and time again, especially during active weather periods. If you have not heard of a sounding or are elementary with understanding them, this blog will convey an in-depth analysis toward understanding how observed weather soundings work.

Observed Sounding Analysis from Tampa Bay, Florida at 12z (8am EDT) on August 14th, 2014. Image: SPC

 

Above is a sounding analysis that was observed in Tampa Bay, Florida, the morning of August 14th, 2014. First off, you will need to know what an observed sounding is and it is simply put: An observed sounding analysis is a view of the current state of the atmosphere at a given location. Weather balloons that are launched at any particular location, usually Weather Forecast Offices (WFOs) are launched at 12z and 00z every day. On some occasions, additional weather balloons are launched if the threat for hazardous weather is significant enough (i.e. May 20th, 2013, a special weather balloon was launched at 18z / 1pm CDT from the National Weather Service in Norman, Oklahoma, just a few hours before Moore, Oklahoma was impacted by an EF-5 tornado).

The following number labels on the sounding will be discussed below…

1) The first thing that is labeled on the observed sounding is the location code, date and time stamp of which the sounding was observed. TBW is the code for Tampa Bay. 140814 is the date, which translates to 08/14/2014. The next thing listed is the time stamp of the observation. In this case, it was 1200z. The “Z” stands for Zulu Time, or Universal Coordinated Time (UTC); they are the same. For brief reference for Zulu to regular time conversions, here is a table explaining the conversions:

12z = 8am EDT, 7am CDT, 6am MDT, 5am PDT

00z = 8pm EDT, 7pm CDT, 6pm MDT, 5am PDT

And when the transition back to standard time occurs, 12z and 00z relate to:

12z = 7am EST, 6am CST, 5am MST, 4am PST

00z = 7pm EST, 6pm CST, 5pm MST, 4pm PST

2) The second label on the observed sounding is the temperature and moisture profiles. Temperature appears as the red line and dew point appears as the green line. As the balloon ascends into the atmosphere, it records both the temperature and the moisture. You may notice that the temperature on this sounding increases with height (if the temperature is increasing, the red line will move to the right) before decreasing. This is a common occurrence within the boundary layer. The boundary layer for brief reference, is usually within the lowest two kilometers of the atmosphere and is where temperatures are most affected by strong day time heating and night time cooling, as well as winds being affected by friction of the Earth. Not to digress from the thermodynamic profiles on the sounding, but I needed to briefly mention the boundary layer for the next reason. The reason why sometimes the temperature may warm with height is called the Nocturnal Inversion. The Nocturnal Inversion is denoted by an increase in temperature with height and can often form on clear nights with relatively calm winds. When the sun rises, the temperature inversion begins to erode as winds start to pick up again due to an influx in temperature with the sun heating the surface.

3) The lines on the side of the sounding that are in different directions are called wind barbs. As the weather balloon ascends into the atmosphere, it records the wind speed in knots (1kt = 1.15mph). The wind barbs vary if the wind speed is weak, strong or significant. A barb will also face a different direction given the direction of which the wind is blowing. In wind shear environments, low-level winds may be blowing out of the south before turning with height to out of the northwest (sound familiar?). Here is an image that depicts the different wind speeds barbs may present on a sounding:

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Wind barb velocity chart. Image: NOAA

 

 

 

 

 

 

 

 

 

 

 

4) Number four on the sounding is showing the pressure coordinates on the sounding. Each day, at any particular location on Earth, pressures vary. The pressure of 1000 millibars (mb) on the sounding was at a height of only 13 meters, equivalent to about 43 feet. As you ascend into the atmosphere, the pressure begins to lower. Did you ever notice the ear popping feeling when flying or driving high into a mountain? Same thing. The lower the pressure on the surface, the more likely precipitation and[or] storms are occurring within that area of the sounding.

5) On every observed sounding, just to the right of the pressure coordinates will be the heights measured in kilometers. The conversion to meters can be done if necessary. Notice that the 1-kilometer (3,280ft) height is below the 850mb pressure height, which indicates that the 850mb height is roughly just under one mile (5,280ft) above the surface. You can expect the boundary layer height to be roughly at or around the 850mb pressure height, especially at night when the boundary layer height lowers due to radiational cooling on the surface.

6) You’re probably wondering what #6 labels on the sounding, but incidentally there are two things that #6 is showing on the sounding. First, it is showing the LCL and then the LFC. The LCL is called the Lifted Condensation Level, where an air parcel becomes saturated as it rises. When this happens, it is the layer at which clouds form. The LCL on the 12z Tampa Bay sounding was right around 0.7-0.8km, or about a half mile above the ground. Low lifted condensation levels indicate that it was likely precipitating around that time. The LFC is the Level of Free Convection, of which the saturated air parcel becomes warmer than the surrounding air and can therefore rise freely which leads to the development of thunderstorms.

7) The previous information discussed in #6 leads right to #7 and that is the EL. The EL is called the Equilibrium Level and is ALWAYS above the LFC. The EL is the level at which a rising air parcel becomes equivalent to the surrounding temperature of the environment. It is also the height at which thunderstorm updrafts can no longer rise upward, and is usually a good indicator of cloud top heights.

8) Eight labels the Freezing Level of the atmosphere, or the FZL. Simply put, the freezing level is the altitude, or height, at which an air parcel plummets below freezing (0°C / 32°F). The freezing level can be critical during the winter in indicating whether or not precipitation will fall as rain, sleet, snow, or ice pellets.

9) Lastly, #9 labels the 0°C line on the sounding. This type of sounding is called a Skew-T, and the temperature lines are skewed at a 45° angle. It is important to trace where the temperature is at the bottom of the sounding and follow the 45° line to the red or green line to determine the actual dew point or air temperature. I have drawn it out on the following image. To determine the pressure height at which the freezing level is, simply just look over the pressure coordinates on the left side of the sounding and you can get an estimate of the pressure height at which the temperature reaches freezing. The same rule applies on finding any other temperature, including surface temperature. Remember, to determine temperature on a sounding, simply find the region on the red temperature line that you are looking for and trace a 45° line to the bottom of the sounding and you can determine the temperature.

8:14 temp #9

Determining temperature on a sounding, labeled here is the 0°C line to determine the freezing level altitude.

 

We will have further discussions on other aspects of weather and forecasting in the near future, including how to read and understand hodographs, station plots and much more. Stay tuned!

Flash Flooding/Severe Storms possible in Northeast Tuesday into Wednesday

The potential exists Tuesday into Wednesday for widespread flash flooding and severe thunderstorms across the Ohio River Valley into the Northeastern United States.

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Quantitative Precipitation Forecast valid Monday 8pm EDT through Tuesday 8pm EDT. Image courtesy of: NOAA / NWS WPC

 

A distinct trough will migrate its way into the Ohio River Valley and Appalachia corridor overnight tonight and throughout the day Tuesday. Mid to upper-level flow will back to southwesterly as the trough advances into the region, bringing an inundation of moisture throughout the region. Ambient cloud cover will inhibit diabatic surface heating, so peak day time temperatures will only reach the lower to mid 70°F range across much of the region. Low-level theta-E advection (Theta-E is the amount of heat present in an air parcel) on consecutive NAM and GFS runs has been indicative of a strong southerly flow component, which could lead to some localized CAPE (measure of instability) at or around 1,000 – 1,500j/kg across the region in the vicinity of the warm front. That said, water loading is probable and heavy rain may occur within stronger storm clusters and[or] any severe storm that can initiate along the cold front as it propagates east.

 

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Flood Outlook valid 2pm EDT Monday through 8pm EDT Tuesday. Image: NOAA / WPC

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Flood Outlook valid 8pm EDT Wednesday through 8pm EDT Thursday. Image: NOAA / WPC

 

 

 

 

 

 

 

 

 

 

In addition to the flood potential, there is also a slight chance for severe thunderstorms across the area with the main storm modes being damaging winds and perhaps a brief tornado. Given the potential for water loading, this could increase downdraft CAPE, so eyes should be kept open for a wet-microburst or two within the stronger storms and[or] clusters of storms. Wind parameters from the low-levels to upper-levels will be strong, so the chances of the wind aloft mixing down to the surface will be heightened Tuesday afternoon across the eastern parts of the Ohio River Valley into the Northeast; severe wind seems to be the most apparent storm mode at this time.

 

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18z NAM +24hr 500mb mid-level wind speeds valid 2pm EDT Tuesday. Image: College of DuPage

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18z NAM +24hr 850mb low-level Theta-E advection valid 2pm EDT Tuesday. Image: College of DuPage

 

 

 

 

 

 

 

 

 

 

The atmosphere is looking to become completely saturated from the surface to low-levels tomorrow across the Mid-Atlantic and Northeast. Flash Flood Watches have already been issued for parts of New England into New York effective Tuesday night into Wednesday. This will be a multi-day event and the flood potential will exist over a spatiotemporal frame of 48-72 hours even after the rain has cleared. While the flooding looks to be minor, it does not take much to sweep a person away in a stream or creek. Always remember to have your NOAA Weather Radio charged and turned on when hazardous weather impedes your area.

 

 

 

 

NOAA “More Confident” About Below-Normal Hurricane Season

Information from NOAA Communications and External Affairs

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Forecasters with NOAA’s Climate Prediction Center raised the likelihood for a below-normal season in today’s update to the Atlantic Hurricane Season Outlook. The update predicts a 70 percent chance of a below-normal season, a 25 percent chance of a near-normal season and only a five percent chance of an above-normal season. The probabilities in the initial outlook issued on May 22 were 50 percent, 40 percent and 10 percent, respectively.

“We are more confident that a below-normal season will occur because atmospheric and oceanic conditions that suppress cyclone formation have developed and will persist through the season.” said Gerry Bell, Ph.D., lead seasonal hurricane forecaster at NOAA’s Climate Prediction Center, a division of the National Weather Service. “Nonetheless, tropical

storms and hurricanes can strike the U.S. during below-normal seasons, as we have already seen this year when Arthur made landfall in North Carolina as a category-2 hurricane. We urge everyone to remain prepared and be on alert throughout the season.”

The primary factors influencing the increased chance of a below-normal season are:

Overall atmospheric conditions are not favorable for storm development. This includes strong vertical wind shear, a weaker West African monsoon, and the combination of increased atmospheric stability and sinking motion. These conditions mean fewer tropical systems are spawned off the African coast, and those that do form are less likely to become hurricanes. These conditions are stronger than originally predicted in May and are expected to last mid-August through October, the peak months of the hurricane season;
Overall oceanic conditions are not favorable for storm development. This includes below-average temperatures across the Tropical Atlantic, which are exceptionally cool relative to the remainder of the global Tropics. This cooling is even stronger than models predicted in May and is expected to persist through the hurricane season; and
El Niño is still likely to develop and to suppress storm development by increasing vertical wind shear, stability and sinking motion in the atmosphere.
The updated hurricane season outlook, which includes the activity to-date of hurricanes Arthur and Bertha, predicts a 70 percent chance of the following ranges: 7 to 12 named storms (top winds of 39 mph or higher), including 3 to 6 hurricanes (top winds of 74 mph or higher), of which 0 to 2 could become major hurricanes (Category 3, 4, 5; winds of at least 111 mph).

These ranges are centered below the 30-year seasonal averages of 12 named storms, six hurricanes and three major hurricanes. The initial outlook in May predicted 8 to 13 named storms, 3 to 6 hurricanes and 1 to 2 major hurricanes.

The Atlantic hurricane region comprises the North Atlantic Ocean, the Gulf of Mexico and the Caribbean Sea. NOAA’s seasonal hurricane outlook is not a hurricane landfall forecast; it does not predict how many storms will hit land or where a storm will strike. Forecasts for individual storms and their impacts will be provided throughout the season by NOAA’s National Hurricane Center.

The Climate Prediction Center also continued the El Niño watch today in its scheduled monthly El Niño/Southern Oscillation Diagnostic Discussion. Forecasters note that although sea surface temperatures across the central equatorial Pacific have recently returned to near average, this cooling is expected to be temporary. El Niño is now favored to emerge during August-October, and to peak at weak strength during the late fall and early winter. The likelihood of El Niño during August-October has decreased to 55 percent (from 75 percent in May), and its likelihood during the fall and winter has decreased to about 65 percent (from near 80 percent).

Man Struck By Lightning; Says It Was “Amazing”

Not everyone who get hit by lightning lives to tell about it.

So, you might call Robb Montejano lucky.

The Seattle man told komonews.com that he was outside walking across a field and saw lightning, so he decided to record the storm with his camera phone.

In less than a minute after pressing record, Montejano saw more lightning and felt a jolt.

He says, “I just felt this surge of electricity go ‘boom’ through my body. The electricity flowing through my body. I can’t describe it. It was amazing.”

Firefighters responded to the emergency call on Sunday and say Montejano is doing fine; just a little shaken up.

Lightning is a killer in thunderstorms. The National Weather Service released this information regarding lightning safety: http://www.nws.noaa.gov/om/lightning/tips.htm

Watch the video:

The Storm Report Announces Marketing Parnership with Warner Brothers Pictures for “Into The Storm”

Into The Storm

Contextual Marketing Program Will Promote Feature Film to Weather-Watchers Across 159 U.S. Radio Stations

AUGUST 1, 2014, BURBANK, CA—Benztown announces that the award-winning radio weather service, The Storm Report, has partnered with Warner Bros. Pictures to promote its upcoming feature film, “Into the Storm”, which opens Friday, August 8 in theaters nationwide. Through the integrated contextual marketing program, The Storm Report and Warner Bros. Pictures have sent “Into the Storm” prize packages and movie passes to its affiliate stations. These station affiliates will sell sponsorships to local advertisers in their markets for local on-air and online contest giveaways of the prize packages and movie passes. Throughout next week, a radio spot (http://bit.ly/soundcloudstormreport) promoting “Into the Storm” will be embedded in The Storm Report Minute, which airs daily on all 159 radio station affiliates of The Storm Report. The Storm Report and its syndicator, Benztown Radio, will execute a variety of social media activations and online promotions to raise awareness of “Into the Storm” and the promotional partnership.

“Into the Storm”, from New Line Cinema, in association with Village Roadshow Pictures, is an action-packed disaster thriller of Silverton, a city ravaged by an unprecedented onslaught of the most furious twisters they’ve ever seen. The entire town is at the mercy of the erratic and deadly cyclones, even as storm trackers predict the worst is yet to come. Most people see shelter, while others run toward the vortex, testing how far a storm chaser will go for that once-in-a-lifetime shot. Told through the eyes and lenses of professional storm chasers, thrill-seeking amateurs, and courageous townspeople, “Into the Storm” throws you directly into the eye of the storm to experience Mother Nature at her most extreme.

The film was directed by Steven Quale (“Final Destination 5”), and produced by Todd Garner (“Zookeeper,” “Knight and Day”). “Into the Storm” will be distributed by Warner Bros. Pictures, a Warner Bros. Entertainment Company, and in select territories by Village Roadshow Pictures. “Into the Storm” is rated PG-13 for sequences of intense destruction and peril, and language including some sexual references. For more information, visit: intothestormmovie.com.

Storm Report provides daily customized weather forecasts around the clock, emergency weather coverage and severe weather updates for over 170 radio stations across the U.S. The Storm Report’s Radio Weather Team of top meteorologists is dedicated to watching the radar, scanning the skies, and being stations’ source for weather information. The Storm Report and The Storm Report Minute (http://www.thestormreport.com) are produced by Dan Holiday Productions and are marketed and distributed by Benztown Radio Networks.

Dave “Chachi” Denes, President of Benztown, said: “We’re thrilled to work with Warner Bros. Pictures to promote their summer popcorn movie, “Into the Storm” through this creative marketing effort. We approached Warner Bros. Pictures with the idea to promote their film through The Storm Report and they have been terrific to work with. We’re especially excited to offer The Storm Report affiliates a perfect sponsorship opportunity to drive revenues for their stations and generate excitement around “Into the Storm”. It couldn’t be a better fit.”

Dan Holiday, President of Dan Holiday Productions and Meteorologist said: “Affiliates of The Storm Report recognize the value of reliable weather information and forecasts that their listeners and communities can depend on 24/7/365. Weather is one of the top two reasons listeners tune in to radio, and “The Storm Report” is known for a polished, professional and award-winning sound and works with each station’s programming department to include local events with its forecast to always deliver a hometown feel. This partnership with Warner Bros. Pictures is a first for us, and helps us to further engage weather-watchers and make them aware of a film that, as weather-lovers and meteorologists, we’re incredibly excited about.”

For more information, visit www.benztown.com, or contact Masa Patterson at mp@benztown.com and at (818) 842-4600.

Polar Opposites: Weekly Radio Station Weather Face-Off

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Like They Say…For Cooler And Drier, Don’t Go To Fort Myers!

It’s been hot and humid, thanks to relentless afternoon storms in the Fort Myers/Naples area. WJPT-FM PD Randy Sherwyn said, “Having grown up in Minnesota, I feel guilty when the weather is sunny and hot. Glistening pools and pineapple slushies are things I never had growing up.”

Meanwhile, an unusually strong cold front has brought much cooler temperatures this week to the Northern United States. KRPR-FM (Rochester, MN) PD Brian Taylor is savoring every bit of it. “Cooler? Anytime it isn’t snowing, we consider it a heat wave! It has been extraordinarily comfortable this summer; for once, Minnesota’s cold is a blessing!”

Revere, Massachusetts Tornado Video

This video from You Tube User Steven Vasco captured Monday’s tornado in Revere, Massachusetts.

WIDESPREAD Severe Weather Outbreak Likely Across Eastern U.S. Sunday

A large scale severe weather event is expected to unfold across the Ohio River Valley into Central Appalachia, leading into the Mid-Atlantic tomorrow.

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Severe Weather Outlook for Sunday, 7/27. Graphic depicts total severe probabilities, with significant risk over the Ohio River Valley into Appalachia. Image: College of DuPage

A deepening trough will support strengthening of a 1004mb cyclone over the Great Lakes region into the Ohio River Valley on Sunday. The potency of the trough will deliver a swath of very cold air to the mid-levels of the atmosphere, which will generate an extremely unstable environment across the Ohio River Valley into the Mid-Atlantic region. Ongoing morning thunderstorm activity is likely antecedent to the cold front as it moves eastward, but rising temperatures will further destabilize the region which will lead to widespread severe thunderstorm development. All storm modes are likely, including the risk for extreme wind, very large hail and tornadoes… Given the impressive wind profiles from the surface to the mid-levels, some STRONG tornadoes could be possible, delineating across eastern Kentucky / Ohio / West Virginia / western Maryland and Virginia / west-central Pennsylvania. Current forecast soundings are continuing to indicate strong westerly flow aloft, which will allow for storms to cluster together and propagate at modest speeds across the terrain.

Here are two forecast soundings, initialized at 2pm EDT today and valid 2pm EDT Sunday:

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NAM forecast sounding valid 2pm EDT Sunday near Charleston, WV. Image: College of DuPage

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NAM forecast sounding valid 2pm EDT Sunday near Washington, D.C. Image: College of DuPage

 

 

 

 

 

 

 

 

 

 

These soundings indicate strong instability (CAPE), with values between 2,000-3,000j/kg. Additionally, wind shear will be supportive of supercell development and the possibility of tornadoes along with the aforementioned severe hail and wind. There does not appear to be much capping in place tomorrow. Spatiotemporally, there could be widespread explosive storm development in the early afternoon across much of the region. Storms at this time are looking to amalgamate into a Mesoscale Convective System (MCS) rather than linear in the latter part of the afternoon; however, all storm modes are to be realized.

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18z NAM mid-level winds / temperature valid 2pm EDT Sunday. Image: COD

Models are indicating very cold air will settle in aloft. With the cold air in place, this will enhance the risk for significant hail in any rotating storm which could also promote intense supercellular development in the Ohio River Valley into Appalachia. This is a large scale event and will initiate in the Ohio River Valley and propagate eastward toward the Mid-Atlantic and coastal regions in the afternoon.

It is a very good idea to have a NOAA Weather Radio on hand, and to also tune into your local news and radio stations tomorrow as they can provide instant hazardous weather information when severe weather impedes your area. 

 

Polar Opposites: Weekly Radio Station Weather Face-Off!

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Hot As Heck in Hays These Days; Alaska Wonders What That’s Like

Hays, Kansas has been under a Heat Advisory for much of the week. Kenai, Alaska is enjoying its fishing season – but also much cooler weather than the contiguous U.S.
KKQY-FM (Hays, KS) OM Boomer has been finding creative ways to keep the temperature down. “It’s been so hot here in Hays that I have been leaving the toilet seat up just to get an ICY stare from my wife.” KKNI-FM (Kenai, AK) GM Bill King (whose photo looks a lot like that of a moose) says, “Our 70 degree highs are way better than 105. If it was that hot we’d have to set up a sprinkler for the moose in our yard.”

Polar Opposites: Weekly Radio Station Face-Off

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Green Bay Turns Down the Heat; Still Too Hot in Arizona

Wisconsin is already prepping for football weather, and the Southwest feels like the Southeast. WOVM-FM (Green Bay) OM Shaun Shouldeen is from Georgia, and doesn’t mind the cold & dry. “High 60’s plus no humidity equals perfection to this Georgia boy!” KKYZ-FM (Sierra Vista, AZ) OM Jeff Davenport says, “We are hot and humid with highs in the 90’s here, but everyday we are getting monsoon storms. We like the rain, but our radio towers don’t like the lightning!”