1 / 33

T.J. Turnage and Jared Maples National Weather Service Grand Rapids, Michigan

Two Cases of QLCS Tornadic Wind Estimation and Implications for Impact Based Warnings. T.J. Turnage and Jared Maples National Weather Service Grand Rapids, Michigan. Outline. QLCS tornado climatology Impact Assessment Warning decisions. QLCS Tornado Climatology.

adanna
Download Presentation

T.J. Turnage and Jared Maples National Weather Service Grand Rapids, Michigan

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Two Cases of QLCS Tornadic Wind Estimation and Implications for Impact Based Warnings T.J. Turnage and Jared Maples National Weather Service Grand Rapids, Michigan

  2. Outline • QLCS tornado climatology • Impact Assessment • Warning decisions

  3. QLCS Tornado Climatology % tornado days due to lines 1998 - 2000 Trapp et al. 2005

  4. QLCS Tornado Climatology • Trapp et al. 2005 • larger proportion of F1 tornadoes from QLCSs than cells • smaller proportion of F0 tornadoes - likely underreported • more F3–F4 tornadoes from cells

  5. Significant Severe Climatology Thompson et al. 2013 Courtesy of SPC

  6. Outline • QLCS tornado climatology • Impact Assessment • Warning decisions

  7. Impact Assessment What is the IBW experiment? • Began in 2012 • Distinguish low and high impact events • Indicate levels of risk Impact Based Warnings Goals • Provide valuable information • Help improve public response • Better addressing of societal needs http://www.crh.noaa.gov/crh/?n=2013_ibw_info

  8. Impact Assessment Phenomena Impacts

  9. Impact Assessment • *FLYING DEBRIS DANGEROUS TO THOSE • WITHOUT SHELTER • *MOBILE HOMES HEAVILY DAMAGED • *CONSIDERABLE DAMAGE TO ROOFS… • WINDOWS...VEHICLES • *EXTENSIVE TREE DAMAGE AND • POWER OUTAGES • Significant SVR • *FLYING DEBRIS DANGEROUS TO • THOSE WITHOUT SHELTER • *MOBILE HOMES DAMAGED OR DESTROYED • *DAMAGE TO ROOFS ...WINDOWS… VEHICLES • *TREE DAMAGE LIKELY • Default TOR

  10. Impact Assessment TORNADO...POSSIBLE REMAIN ALERT FOR A POSSIBLE TORNADO! TORNADOES CAN DEVELOP QUICKLY FROM SEVERE THUNDERSTORMS. IF YOU SPOT A TORNADO GO AT ONCE INTO THE BASEMENT OR SMALL CENTRAL ROOM IN A STURDY STRUCTURE. INTENSE SQUALL LINES CAN SOMETIMES PRODUCE BRIEF TORNADOES AND WIDESPREAD SIGNIFICANT WIND DAMAGE. ALTHOUGH A TORNADO IS NOT IMMEDIATELY LIKELY...IT IS BEST TO MOVE TO AN INTERIOR ROOM ON THE LOWEST FLOOR OF A BUILDING. THIS STORM MAY CAUSE SERIOUS INJURY AND SIGNIFICANT PROPERTY DAMAGE

  11. Outline • QLCS tornado climatology • Impact Assessment • Warning decisions

  12. Warning Decisions Decision Factors Near Storm Environment (NSE) Storm Interrogation Ground Truth

  13. Near Storm Environment (NSE) SPC Tornado Environment Browser

  14. Case 1 06/22/2010 ~04Z

  15. Near Storm Environment (NSE) 06/22/2010 04Z Nontor EF0 EF2+ Nontor EF0 EF2+ MLCAPE MLCIN Thompson et al. 2013

  16. Near Storm Environment (NSE) 06/22/2010 04Z Nontor EF0 EF2+ Nontor EF0 EF2+ 0-1 km BWD 0-6 km BWD Effective BWD Thompson et al. 2013

  17. Near Storm Environment (NSE) 06/22/2010 04Z Nontor EF0 EF2+ Nontor EF0 EF2+ STP Effective STP 0-1 km SRH Effective SRH Thompson et al. 2013

  18. Storm Interrogation Principles Atkins and St. Laurent MWR 2009

  19. Storm Interrogation Principles Trapp et al. 1999 Descending TVS Trapp and Weisman 2003 Non-Descending TVS

  20. Storm Interrogation 06/22/2010 04Z Reflectivity NROT Where did the “tornado” occur?

  21. Storm Interrogation 06/22/2010 04Z N

  22. Storm Interrogation Crest Trough 06/22/2010 04Z Gravity wave interaction?

  23. Case 2 11/17/2013 ~19Z

  24. Near Storm Environment (NSE) 11/17/2013 19Z Nontor EF0 EF2+ Nontor EF0 EF2+ MLCAPE MLCIN Thompson et al. 2013

  25. Near Storm Environment (NSE) 11/17/2013 19Z Nontor EF0 EF2+ Nontor EF0 EF2+ 0-1 km BWD 0-6 km BWD Effective BWD Thompson et al. 2013

  26. Near Storm Environment (NSE) 11/17/2013 19Z Nontor EF0 EF2+ Nontor EF0 EF2+ STP Effective STP 0-1 km SRH Effective SRH Thompson et al. 2013

  27. Storm Interrogation Reflectivity NROT 11/17/2013 19Z

  28. Storm Interrogation 11/17/2013 19Z N

  29. Storm Interrogation 11/17/2013 19Z

  30. Summary QLCS Tornadoes • Climatologically common • Climatology strongly favors ≤ EF1 wind • Damage often looks like “straight line” wind • Similar impacts to SVR t-storms

  31. Summary (cont) Warning Decision - NSE • Shear / SRH best discriminate significant tornado environments • MLCAPE / MLCIN / STP less helpful

  32. Summary (cont) Warning Decision – Storm Interrogation • QLCS mesovortices: • Usually north of bow apex • Strongest wind south of circulation • May or may not descend • Intensity often regulated by gravity waves • Radar presentation can be deceptive

  33. Thank you! References • Atkins, Nolan T., Michael St. Laurent, 2009: Bow Echo Mesovortices. Part I: Processes That Influence Their Damaging Potential. Mon. Wea. Rev.,137, 1497–1513. • Thompson, R.; Smith, B.; Dean, A.; Marsh, P.. Spatial Distributions of Tornadic Near-Storm Environments by Convective Mode. E-Journal of Severe Storms Meteorology, North America, 8 1 09 2013. • Trapp, R. J., E. D. Mitchell, G. A. Tipton, D. W. Effertz, A. I. Watson, D. L. Andra, M. A. Magsig, 1999: Descending and NondescendingTornadic Vortex Signatures Detected by WSR-88Ds. Wea. Forecasting, 14, 625–639.Trapp, Robert J., Sarah A. Tessendorf, Elaine Savageau Godfrey, Harold E. Brooks, 2005: Tornadoes from Squall Lines and Bow Echoes. Part I: Climatological Distribution. Wea. Forecasting, 20, 23–34. • Trapp, Robert J., Morris L. Weisman, 2003: Low-Level Mesovortices within Squall Lines and Bow Echoes. Part II: Their Genesis and Implications.Mon. Wea. Rev., 131, 2804–2823. • Impact Based Warnings: http://www.crh.noaa.gov/crh/?n=2013_ibw_info

More Related