LMA Assessment

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LMA Assessment
Dennis Buechler
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Total Lightning Impacts Decision Making

• Has directly contributed to several correct
  severe warning decisions at HUN and OHX.
• the LMA density map gives you a great overall
  view of where storms with intensifying updrafts
  are located. So it gives you a good map of where
  to concentrate attention.
• I believe the flash density rates were the
  primary factor in holding off on a warning.
• Data archived by WFO
• Used in Warning Event Simulator for office
  training and research

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Operational Evaluations

• Web based LMA survey developed for the WFOs
• Completed after an event in which the LMA data
  was used
• Survey also available at other WFOs (OHX, BMX,
  FWD)

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(No Transcript)
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LMA Benchmarking ResultsNovember 2003 through
November 2005

• 28 surveys filled out by HUN and OHX, none yet
  from BMX 1 in 2003, 8 in 2004, 19 in 2005
• Severe Weather Scenarios
• Large Hail
• Tornadoes
• Straight Line Winds
• Cells Embedded in Lines
• Supercells
• Microburst-producing single pulse summer TRW

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LMA BenchmarkingOHX (Nashville) Results

• 5 Surveys in 2005
• All indicated the data useful identifying cells
  with strongest updrafts- helped forecaster
  identify storms needing more attention
• LMA data used to verify other data- radar,
  eye-witness reports- used by forecasters in the
  warning decision
• 2 reports warning lead time increased by 2-3 min
• Forecasters gaining confidence in using the data

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LMA BenchmarkingHUN (Huntsville) Results

• 23 Surveys completed 19 used in analysis
• 1 case problems with data
• 3 cases data not updating properly
• In 11 cases there was a positive impact -
  increased warning lead time of 1-9 min
• In remaining 8 cases, either no impact on warning
  decision or forecaster warned based on other
  available data
• In 2005, 9 of 12 surveys indicated improvement in
  lead time with LMA

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LMA Benchmarking Interim ResultsRankings on
Scale of 1-10
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Greatest LMA impact in operations

• Low to moderate severe events
• At greater distances from the radar
• Sub radar interval cell information
• Detecting initial cloud to ground strikes
• Local case studies have shown lead times on the
  order of several (3-5) minutes
• Increased lead times for TAF updates and Airport
  Weather Warnings

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WES Cases for Training and Research
Selected archived WES cases of different types of
weather events (including a null case) for use in
training and further research.
T Tornado W Strong Winds FF Flash Flood H
Large Hail Null No SVR
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Summary

• Surveys and forecaster feedback indicate that LMA
  data is useful
• Improved situational awareness
• Improved forecast confidence
• Longer estimated warning lead times
• Surveys useful in reviewing events
• Surveys valuable for choosing case studies
• Encourages feedback