Modern social media technology is changing the world of thunderstorm reporting.  The National Weather Service (NWS) has released an experimental way to send storm reports back to the Weather Forecast Office (WFO).  The NWS has chosen to use Twitter to allow the general public to send storm reports back to the local offices.  This will not supersede other ways that WFOs get real time information (Amateur Radio Operators, Skywarn Spotters, Local Law Enforcement, Toll Free Line, etc…).  This system is currently in the experimental phase during the 2010 calendar year.  It will then be evaluated on how it performed, the quality of data the public sent in, and the operational qualities for a possible upgrade to operational status sometime in 2011 or beyond.

One of the features in Twitter is the use of Geotagging.  That is when you tweet on any device with access to a GPS device like a laptop dongle add-on or more commonly a GPS unit built into today’s newer smartphones which are becoming more common each day.  This allows your device to automatically take your GPS location (basic Lat/Lon) and send that along with your report.  If your tweeting device does not have access to a GPS unit, you can also manually enter in your location.  Of course, the more accurate the location, the higher quality the storm report data is.

Since some of the data has Geotagging location data, it can be plotted using any Geographic Information System (GIS) for internal or real-time external use.  There are currently examples at the bottom of the NWS page on this.

This will help the NWS not only with real time warning planning, but it will also help to highlight areas to be looked at in post-storm damage assessments.  More damage locations to survey will mean improved data to send back to help local agencies assist in providing short term support after the storm (e.g. Red Cross). It will help local governments know how much infrastructure there is to rebuild and improve local procedures.  Finally, for the NWS, it will aid in improving their damage assessment materials for inclusion in future papers about the event and the EF-Scale damage documentation and training.

So, you can get involved this season and help the NWS out by contacting them about significant weather events during the year.  Just be aware that you will not get a response from the NWS from your tweet report.  It is up to the forecasters on duty to determine if a report is significant or not with the current weather situation.

You tweet:” #wxreport (your report)” to send your report in if you have Geotagging turned on.

You tweet “#wxreport WW (your location) WW (your significant weather event)” if you do not have Geotagging enabled or available.  Try to be as specific as possible.

The NWS considers the following to be significant events, and they are looking for them:

Strong Winds

Large Hail

Tornadoes/Funnel Clouds

Flooding

Snowfall amounts during and after an event

Freezing Rain or Freezing Drizzle which form ice glazes on objects

Dense Fog with half a mile or less of visibility

Here is the main NWS web page with all the details about this program (thanks for the link NWS Twin Cities, MPX)

http://www.weather.gov/stormreports/

Here are the current reports:

http://twitter.com/#search?q=%23wxreport

If you want to join in, get your own Twitter Account here:

https://twitter.com/signup

©2010 Charles Schoeneberger

About Chuck

Chuck has a background in Atmospheric Sciences and a degree from the University of North Dakota, Grand Forks. He has a background in operational forecasting producing products for transportation needs with the 511 system and Departments of Transportation in Minnesota, North Dakota, South Dakota, and Montana with Meridian Environmental Technology Inc. of Grand Forks, ND.  He is looking for new job opportunities in the operational forecasting realm, and he blogs for the Minneapolis StarTribune newspaper about statewide weather.  In addition, Chuck has a background in Geographic Information Systems and is also looking for ways to apply these skills towards weather outreach and communications.    He is a native of Minnesota, just outside the Minneapolis/St. Paul metro area and enjoys all four seasons and the constantly changing conditions.

Minneapolis StarTribune Weather Watchers Blog:

http://www.startribune.com/weatherwatchers/chuckschoeneberger.html

University of North Dakota, Grand Forks, Atmospheric Sciences Department:

http://www.atmos.und.edu/Default.aspx

National Weather Service Warning Decision Training Branch:

http://wdtb.noaa.gov/

COMET at UCAR:

http://www.comet.ucar.edu/

Twin Cities Chapter of the American Meteorological Society:

http://twincitiesams.org/

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In my last post relating Geographic Information Systems (GIS) and Meteorology, I mentioned that GIS is a way to relate the real world to the raw and derived meteorological output.  It is far from a perfect relation of course.  Many GIS datasets have much larger scales than meteorological output (e.g. roads in the misoscale/meso-gamma scale and WSR-88D data at the mesoscale), so they are too precise relative to meteorological datasets.

I first want to do a quick review of precision.  Precision is the level of measurement and exactness of a dataset.  It often gets confused with accuracy, which is the degree in which the data matches the true or accepted values.  It should be noted that high accuracy does not imply high precision and vice versa (Foote 2000).  The terms are often used interchangeably and are often confused with each other.

Let’s set up a basic overlay with a long range WSR-88D radar scan and a road Shapefile dataset from the US Census Bureau’s Tiger Line Shapefile set as an example.  The current dataset has an expected error of around 7.6m or 25ft.  (By road engineering standards, this dataset is considered a cruder dataset, but in this case it is the more accurate dataset.)  For the radar data at that range, the beam height and width values are many orders of magnitude greater than the road file.  For example, at 150mi from the radar the beam width is about 15,000ft wide and at 250mi it is 25,000ft wide (Letxa.com 2000), and the height at that distance varies by tilts, from anywhere from 15,000-70,000ft.

This can be shown clearer when trying to compare actual tornado tracks to the locations of the radar returns.  In 2006 Douglas Speheger and Richard Smith of the Norman, Oklahoma Weather Forecast Office compared the two.  They found significant errors at both close and distant ranges between the range gate value locations and track locations as shown in Figure 1.

Figure 1

At closer ranges, (30mi) radar returns were off by 1-2 miles of the post-event surveyed track and at longer ranges (110mi) the returns were off by 8 miles.  They pointed out that location error of 1-2mi is unacceptable for real time pathcasting of tornado tracks as shown in Figure 2.

Figure 2

Some of the error is from tilted mesocyclone structure.  The weakness is in the beam height at that distance which can only be mitigated with a higher density radar network.

The Warning Decision Training Branch (WDTB) has an online course related to this paper called “Pathcasts in Severe Local Storms”.  The course also mentions from Speheger and Smith’s paper that when producing warnings, cities and notable locations are represented as points in AWIPS when many urban locations are best represented by polygons showing the outer boundary of the area, and right now it mentions how best to adjust for the locations for the maximum clarity in each warning product.

Another example would be surface observations.  ASOS/AWOS locations at airports are spread out somewhere between the synoptic and mesoscales, that if they were gridded and interpolated, a useful grid would be around 30km by 45km (UW Extention).  You can never have too many observation sites, but it good to know the scale limitations with the current system.

Error, Accuracy, and Precision, Foote 2000

http://www.colorado.edu/geography/gcraft/notes/error/error_f.html

On the Imprecision of Radar Signature Locations and Storm Path Forecasts

http://www.spegweb.com/papers/radar/

Technical Explanation of NEXRAD, Letxa.com

http://www.letxa.com/nexradtech.php

Tiger/Line Shapefiles 2009 Technical Documentation (Page 31)

http://www.census.gov/geo/www/tiger/tgrshp2009/TGRSHP09.pdf

UW Extention

http://www.soils.wisc.edu/wimnext/asos/asos.html

About Chuck

Chuck has a background in Atmospheric Sciences and a degree from the University of North Dakota, Grand Forks. He has a background in operational forecasting producing products for transportation needs with the 511 system and Departments of Transportation in Minnesota, North Dakota, South Dakota, and Montana with Meridian Environmental Technology Inc. of Grand Forks, ND.  He is looking for new job opportunities in the operational forecasting realm, and he blogs for the Minneapolis StarTribune newspaper about statewide weather.  In addition, Chuck has a background in Geographic Information Systems and is also looking for ways to apply these skills towards weather outreach and communications.    He is a native of Minnesota, just outside the Minneapolis/St. Paul metro area and enjoys all four seasons and the constantly changing conditions.

Minneapolis StarTribune Weather Watchers Blog:

http://www.startribune.com/weatherwatchers/chuckschoeneberger.html

University of North Dakota, Grand Forks, Atmospheric Sciences Department:

http://www.atmos.und.edu/Default.aspx

National Weather Service Warning Decision Training Branch:

http://wdtb.noaa.gov/

COMET at UCAR:

http://www.comet.ucar.edu/

Twin Cities Chapter of the American Meteorological Society:

http://twincitiesams.org/

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Any literature teacher will tell you that man vs. nature is a theme of conflict in stories going back as far as the ancient Greeks in history and probably even farther back into prehistory.  In its most basic form, it is man’s attempt at overcoming obstacles in his path such as bitter cold, extreme drought, a mountain, a valley, or poor soil quality.

Some cultures give nature a personality with human-like characteristics as in Mother Nature or Old Man Winter.  Americans tend to do this when we dislike the forecast.  Other cultures grant parts of nature God-like qualities and feel the need to appease them.  With the dawn of mass media in modern times, we have taken the theme even further with movies like Twister and The Day After Tomorrow.  There is even a belief in something called “Gaia’s Revenge,” which basically states that the earth will find ways to get revenge on man for his mistakes and mistreatment of the planet.

While it makes sense that we focus on the one thing in our world that we can’t control and that has so much influence on our daily lives and think of it as a source of conflict and struggle, we need to remember that nature does not have intentions.  Like anything else in the world, nature is ruled by cause and effect and runs its course in a cyclical fashion.  Man does better on the whole when he understands these cycles and learns to work with them instead of struggling against them.

Here are a few examples of how man has learned to use nature to his benefit ranging from the extreme to the mundane:

In drought stricken areas of China, poor farmers dig canals to capture water during the annual spring thaw.  The thaw turns a trickle of water into a roaring river every year.  The farmers have learned that by digging canals to divert the water to their fields and making the most of the river’s relatively short life, they can more easily raise their crops.

Native Americans of the northeast planted three beans, called the Three Sisters, together to make the most of their growing season and their soil.  Corn, beans, and squash complement each other well when they grow together.

“Corn provides support for beans. Beans, like other legumes, have bacteria living on their roots that help them absorb nitrogen from the air and convert it to a form that plants can use. (Corn, which requires a lot of nitrogen to grow, benefits most.) The large, prickly squash leaves shade the soil, preventing weed growth, and deter animal pests.”

Rain gardens are growing in popularity as a way to achieve a similar goal.  Using plants native to your area to create a rain garden requires less fertilizer and helps to alleviate runoff problems in urban and suburban areas.  The gardens capture rainfall and the soil filters it on its way to the aquifers and tributaries thus helping to lessen flash flooding and to aid in better water quality.

These are just a few examples of how working with nature and taking advantage of what nature has to offer can help man overcome obstacles and even thrive in the face of adverse conditions.  There are many more out there.  The key thing to remember is that nature is what it is and nothing more.  It is not a force to be reckoned with, but a force to be reconciled with.  We may complain about the destruction hurricanes can cause, but the Southeastern United States without a land falling hurricane quickly falls into drought.  Even the most destructive weather has its benefits.

Source for Three Sisters quote: www.kidsgardening.com

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On the morning of April 11, 1965, warm, humid air was flowing northeastward into the Midwest ahead of a fast moving low pressure center that was dropping southeast out of Minnesota toward Iowa.  A warm front was moving northward across Illinois and Indiana.  Strong warm advection was occurring across the region in the wake of the warm front with temperatures in the lower 80s in some places. A strong cold front trailed southward from the low.  In the upper levels of the atmosphere, a huge, positively tilted trough extended from an upper low center over the upper Midwest back to southern California.  A strong jet stream was flowing over the Midwest with a 185 mph jetmax located on the morning sounding at Dodge City, Kansas. The Weather Bureau’s Severe Local Storms Unit (SELS) at Kansas City issued five tornado forecasts that day.  Every tornado but two occurred in a forecast area.

The first tornado touched down in Iowa just before 1 p.m.  The Weather Bureau in Waterloo had no radar.  A radio station in Cedar Rapids spotted the developing storm on its own aviation radar and alerted the Weather Bureau forecaster.  The next twelve hours would be horrible.  When everything was over, there were 47 tornadoes across seven states, including Iowa, Wisconsin, Illinois, Indiana, Michigan and Ohio.  There were 21 killer tornadoes. Seventeen of the tornadoes were violent (F3 or greater.)  A total of 260 people were killed and 3,442 injured.  It was the most significant tornado outbreak since March 18, 1925 when the Tri-State Tornado occurred.  It is the third deadliest tornado outbreak on record behind the Tri-State outbreak and the April 3, 1974 Super Outbreak. In Illinois, Crystal Lake was hard hit, with five fatalities from a F4.  A massive F4 killed ten people at Koontz Lake, Indiana.  A terrifying series of pictures was snapped near Goshen, Indiana as a pair of massive funnels roared by.  The towns of Russiaville and Alto were destroyed, with dozens of fatalities. At one point, blanket warnings had to be employed, covering up to nine counties at a time, as forecasters struggled to keep up with the fast breaking storms.  Indiana was the hardest hit state, with 138 fatalities.  As some of the powerful tornadoes moved from Indiana into Michigan, warnings could not be telephoned ahead because the phone networks were out.  A total of 53 people died in Michigan.  In Ohio, 60 people died from violent tornadoes during the late evening.  Toledo was hard hit.

The Palm Sunday outbreak led to significant improvements in the warning system, but why?  There were good forecasts. The dangerous storms were identified in plenty of time.  The warning system had failed.   People interviewed after the storm did not understand what a tornado “forecast” was.  They didn’t understand the difference between “forecasts” and “warnings.”  The next year, tornado forecasts would be named “watches.”  One problem was that radar coverage was woefully inadequate across the outbreak area and there was poor communication between the Weather Bureau and media sources.  Tornado forecast areas were defined as circles, triangles, and other kinds of shapes.  The outbreak would lead a trend toward parallelogram tornado watches.  They would begin in 1970.  After the outbreak, the Weather Bureau started holding preparedness meetings as well as spotter talks and training.  The goal became to saturate the public with information on tornadoes. NOAA Weather Radio would be another legacy of the outbreak.

Bill Murray is a forecaster for AlabamaWX.com, the official weather blog at Alabama’s ABC33/40. Get a daily dose of his weather history at www.twitter.com/wxhistorian. He is also one of the hosts at WeatherBrains, the weekly netcast that’s all about weather. Listen at www.WeatherBrains.com or subscribe through the iTunes Music Store. It’s free!

Photo courtesy of NOAA Photo Library

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Do you remember the last time that a tornado killed one hundred or more people?  Do you remember the last time that a U.S. passenger jet crashed because of a microburst?   Probably not, because these events have not happened in a long time.  Weather entrepreneur Mike Smith tells us why most of us can’t remember than far back in his recently released book Warnings:  The True Story of How Science Tamed the Weather.

Too often we hear the media say that a storm struck “without warning,” but in reality, that hardly ever occurs.  The probability that a significant event will be warned for is approaching 100%.   People have ample warning about most storms now.  The issue is whether they receive the warnings, understand them and take appropriate action.  That was not the case on April 9, 1947.  The people in the destroyed town of Woodward, Oklahoma never knew what hit them, even though the storm that produced the massive tornado had been noted over an hour earlier by an FAA weather observer.   It was no one’s job to warn the people ahead of the storm.

A year later, the military had enough of surprise tornadoes.  But it took a miracle event in Oklahoma City to prove that the destructive storms could be forecasted.  It took three more years and numerous fatalities to convince the bureaucrats at the U.S. Weather Bureau to bring warnings to the public.  Even then, the town of Udall, Kansas died in its sleep at 10:35 p.m. on May 25, 1955.

But a steady stream of improvements over the decades in the weather enterprise led to a May night in 2008 when a tiny Kansas prairie town lay in the path of another massive twister.  But this time, powerful Doppler radars tracked the storm’s every move.  Forecasts were accurate hours and days in advance.  Warning systems worked flawlessly.  Even though most of the town of Greensburg was obliterated, the death toll was extremely low.

When is the last time you heard of a hurricane killing 1,000 people?  Oh, yeah.  Katrina.  But the author argues that Katrina was murder by bureaucracy.  It still takes more than a perfect forecast to prevent loss of life. Think Hurricane Ike.

It is easy to focus on the mistakes that are made in the warning process.   It is still an imperfect science.  But Smith shows us that the progress that has been made in reducing fatalities from severe weather has surpassed that of curing cancer, preventing heart disease deaths and reducing automobile death rates.

About Bill

Bill Murray is a forecaster for AlabamaWX.com, the official weather blog at Alabama’s ABC33/40. Get a daily dose of his weather history at www.twitter.com/wxhistorian. He is also one of the hosts at WeatherBrains, the weekly netcast that’s all about weather. Listen at www.WeatherBrains.com  or subscribe through the iTunes Music Store. It’s free!

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Weather maps on the morning of Wednesday, April 3, 1974 gave clear indications that a major outbreak of severe weather was likely across a wide part of the United States.  About 4 a.m., the forecaster at the Severe Local Storms Center in Kansas City issued the 24 hour severe weather outlook.  It was a masterful forecast. It called for “scattered” severe thunderstorms.  This was a higher category than the usual “few” severe storms listed in the forecast.  It would be the equivalent of a moderate risk outlook today.

It was warm and muggy when I awakened that morning.  Oh, no.  Tornado weather.  Again.  I was quite weary of severe weather events back then.  Weather was definitely a very real fear, not a fascination for this 12 year old that was growing up in a Birmingham suburb..  We had just dodged a bullet on Monday night as April Fool’s Day tornadoes ripped through the state, killing a Huntsville man.

At 7 a.m.  that Wednesday morning, it was 71F with a dewpoint of 70F.  Skies were cloudy.  There was a southerly wind gusting to 15 mph already.  My aneroid barometer read 29.75.  All bad signs for early April.  The Today Show broadcast the SELS Severe Thunderstorm Forecast each morning, calling it the SKYWARN map.  It looked ominous.

The sun made occasional appearances through the morning hours, even as temperatures soared into the 80s and winds gusted to over 30 mph.  I was in the 6th grade, and my wonderful teacher JudyThornton, decided we should have class outside.  She caught me standing off to the side watching the low cumulus clouds racing northward in the strong winds.  She commented that it was a beautiful day.  I shook my head.  It was going to be bad, I told her.  How so, she asked.  Tornadoes, I said.  She chided me for being a worrier.  It wasn’t going to do anything, she said.  I felt those gusting winds and knew better.   My dad brought my lunch that day, and he told me that a tornado watch had been issued.  I had a strong feeling of foreboding.

My mom picked us up from school at 3 o’clock.  Storms were building.  By the time we got home, tornado warnings were being issued for Jefferson County.  A tornado did touch down near Concord, west of Birmingham, but the storms passed our home in northeastern Jefferson County and I breathed a sigh of relief.  But that relief would be short lived.  A new tornado watch was issued at 5:45 p.m. for a large part of Alabama.  It looked like it was going to be a long night of severe weather in Alabama.  We had no idea…

News reports from the afternoon of April 3, 1974 were disturbing.  Devastating tornadoes hit Louisville, Cincinnati and Brandenburg, Kentucky.  The town of Xenia, Ohio was hard hit, with lots of fatalities.  In Alabama, the atmosphere had bubbled over with some mid afternoon storms that produced some damage reports, but nothing really bad had happened yet.   As the afternoon waned, the atmosphere took on a mournful, ominous feel however, with powerful gusts of wind.

Frightening reports started to come in around 6 p.m.  Tornadoes on the ground in Lawrence County.  “Big and powerful.  Taking everything in their path.”  Not good.  The radio was my constant companion as I listened intensely for bulletins.  WFMH in Cullman was also an amazing source of weather information, even when power went out at their studios.  But unlike today, real information was hard to come by.

I clearly remember Wendell Harris interrupting programming on Channel 13 in Birmingham with a bulletin that fatalities were mounting in Northwest Alabama.  But the scariest reports started around 9:30 p.m. A huge severe thunderstorm in Marion County had three well defined hook echoes in it.  At 9:04 p.m., one of the most powerful storms ever to strike Alabama roared straight through the town of Guin.

Just before 10 p.m., the announcers at WFMH in Cullman were broadcasting from their transmitter, observing the storm to their northwest.  They read a bulletin from the Weather Service that stated that the storm over Marion County was moving at over 120 mph!  I had always heard that the faster the storm was moving, the more severe it must be.  Moving at double anything I had ever heard of.  At 10:35 p.m., the NWS Birmingham took a dramatic step, placing the northwestern quarter of the state of Alabama under a giant tornado warning and telling people to take cover if any thunderstorm approached their area.  Tornadoes were too numerous to warn for individually.

Just before 10:30 p.m., there was a report that a tornado was bearing down on the Huntsville Decatur Jetport.  At 10:45 p.m., there was a report that the NWS Huntsville was abandoned and the Birmingham weather office was taking over warning responsibility.

My dad got home from work at 11:30 p.m., and I was in a tizzy.  The report had just been received that Guin had been struck.  It sounded like the world was coming to an end.  I decided to turn off the radio about 1 a.m. and hit the sack, fully expecting we would be hit by a tornado during that terrible, terrible night.

The next morning, the death toll in Alabama and across eleven states was appalling.  315 killed by 148 tornadoes in 24 hours.

Bill Murray is a forecaster for AlabamaWX.com, the official weather blog at Alabama’s ABC33/40. Get a daily dose of his weather history at www.twitter.com/wxhistorian. He is also one of the hosts at WeatherBrains, the weekly netcast that’s all about weather. Listen at www.WeatherBrains.com  or subscribe through the iTunes Music Store. It’s free!

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Every year at about this time, March and April, meteorologists hear a similar refrain:  “What’s up with this crazy weather?”  For a met, the answer is simple.  It’s spring!

Spring is a time of transition and contrasts.  As long, dark nights and cold days give way to longer, warmer days, the atmosphere really seems to come to life.  The cold Arctic air masses of winter haven’t fully given up their hold on the northern climates, but the warmer air masses are moving in as the sun makes its trek north crossing the equator and moving toward the Tropic of Cancer.

The stark contrasts in air masses set up strong frontal systems, which move across the country touching off severe weather, especially on the Plains, in the Midwest, and in the south early in the season.  It’s naturally a rainy season for much of the country.

At the same time, places that had large amounts of snow during the winter begin to see the snow melt and run off.  The higher the snow pack, the more likely there will be flooding in these areas.  When you add rain, especially with convective storms, to this mix, you increase the runoff.  The tributaries swell and the rivers overrun their banks.  Parts of New England are experiencing this process right now.  The Red River Valley of the North experienced it just over a week ago and last year.  Two years ago, the bull’s eye seemed to be on Iowa and Wisconsin.

It happens.  It is an annual occurrence, and overall it’s not unusual.  Human beings typically have a short memory when it comes to the weather as well as preset notions of what “normal” is.  Sometimes we just have to remind ourselves that in spring, “crazy weather” is normal.

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