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Convective Weather Trainee Workbook QTP TW 1W0X1 1 Feb 2001 Air Force Weather Qualification Training Package Convective Weather Trainee Workbook Providing Standardized Training to “Exploit the Weather for Battle” AIR FORCE WEATHER AGENCY TRAINING DIVISION 106 Peacekeeper Dr., Ste 2N3 Offutt Air Force Base NE 68113-4039 QTP TW 1W0X1 REPORT DOCUMENTATION PAGE Form Approved OMB No. 0704-0188 The public reporting burden for this collection of information is estimated to average 1 hour per response, including the time for reviewing instructions, searching existing data sources, gathering and maintaining the data needed, and completing and reviewing the collection of information. Send comments regarding this burden estimate or any other aspect of this collection of information, including suggestions for reducing the burden, to Department of Defense, Washington Headquarters Services, Directorate for Information Operations and Reports (0704-01881, 1215 Jefferson Davis Highway, Suite 1204, Arlington, VA 22202-4302. Respondents should be aware that notwithstanding any other provision of law, no person shall be subject to any penalty for failing to comply with a collection of information if it does not display a currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE (DD-MM-YYYY) 2. REPORT TYPE 3. DATES COVERED (From - To) 9 April 2001 Final 4. TITLE AND SUBTITLE 5a. CONTRACT NUMBER Air Force Weather Qualification and Training Package - Convective QTP Forecasting Workbook, Trainer's Guide, and Evaluation Package 5b. GRANT NUMBER 5c. PROGRAM ELEMENT NUMBER 6. AUTHORS) 5d. PROJECT NUMBER MSgt Mercer MSgt Bridges 5e. TASK NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAMES) AND ADDRESSES) 8. PERFORMING ORGANIZATION Headquarters Air Force Weather Agency (HQ AFWA) REPORT NUMBER Technical Training Branch (DNTT) QTP TW 1WOX1 QTP TG 1WOX1 QTP EP 1 WOX 1 9. SPONSORING/MONITORING AGENCY NAMES) AND ADDRESSES) 10. SPONSOR/MONITOR'S ACRONYMS) 11. SPONSOR/MONITOR'S REPORT NUMBERS) 12. DISTRIBUTION/AVAILABILITY STATEMENT Approved for public release, distribution unlimited 13. SUPPLEMENTARY NOTES 14. ABSTRACT 15. SUBJECT TERMS Convective QTP 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF 18. NUMBER 19a. NAME OF RESPONSIBLE PERSON a. REPORT b. c. THIS PAGE ABSTRACT OF ABSTRACT PAGES Unclassified Unclassified Unclassified 19b. TELEPHONE NUMBER (include area code/ Standard Form 298 (Rev. 8/98) Prescribed by ANSI Std. 239.18 ii QTP TW 1W0X1 Acknowledgments Headquarters Air Force Weather Agency Commander Col. Robert H. Allen Director, Air & Space Science Lt. Col. Ray M.Clark Authors MSgt Gary D. Mercer MSgt Ronald E. Bridges Headquarters Air Force Weather Agency Technical Training Branch (DNTT) Editorial Staff SMSgt Michael J. Przybysz & MSgt Gary C. Justus Headquarters Air Force Weather Agency Technical Training Branch (DNTT) Address communications to: Convective QTP Headquarters Air Force Weather Agency Training Division (DNT) 106 Peacekeeper Dr, Ste 2N3 Offutt AFB, NE 68113-4039 Phone Comm (402) 294-2117 DSN 271-2117 Fax Comm (402) 292-8207 DNS 272-8207 [email protected] iii QTP TW 1W0X1 Table of Contents Trainee Workbook Instructions ....................................................................................... 1 Module 1 – Characteristics of Thunderstorms ................................................................. 2 1.1. General Information Concerning Convection....................................................... 4 1.1.1. Thunderstorm Conditions ............................................................................ 5 1.2 Types of Convection ............................................................................................. 9 1.3 Single Cell Thunderstorm...................................................................................... 9 1.3.1 Cumulus Stage.............................................................................................. 10 1.3.2 Mature Stage ................................................................................................ 10 1.3.3 Dissipating Stage.......................................................................................... 11 1.4 Multicell Thunderstorms ..................................................................................... 12 1.5 Supercell Thunderstorms..................................................................................... 15 1.5.1 Mesocyclone ................................................................................................ 15 1.5.2 Forward Flank Downdraft............................................................................. 18 1.5.3 Rear Flank Downdraft .................................................................................. 19 1.5.4 Weak and Bounded Weak Echo Region........................................................ 20 1.5.5 Two Cell Mesocyclone ................................................................................. 20 1.5.6 Supercell Visual Clues.................................................................................. 21 1.5.7 Types of Supercells ...................................................................................... 24 1.6 Storm Motion...................................................................................................... 25 1.6.1 Supercell Movement.................................................................................... 26 1.7 Lightning ............................................................................................................ 27 1.7.1 CONUS Lightning Climatology.................................................................... 30 1.7.2 Other Types of Thunderstorm (Lightning) Climatology................................ 31 1.7.3 Lightning and Severe Weather...................................................................... 34 Module 2 – Mesoscale Convective Systems .................................................................. 38 2.0 Squall Lines and Bow Echoes ............................................................................. 40 2.1 Typical Properties of a Squall Line...................................................................... 41 2.2 Structure of a Squall Line.................................................................................... 42 2.3 Environments Associated with Squall Line/Bow Echo ........................................ 42 2.3.1 Summer (Weak Synoptic Pattern)................................................................. 43 2.3.2 Late Winter/Spring (Strong Dynamic Forcing) ............................................. 44 iv QTP TW 1W0X1 2.4 Formation of Squall Lines ................................................................................... 45 2.5 Derechos............................................................................................................. 46 2.6 Mesoscale Convective Complex.......................................................................... 52 2.6.1 Physical Characteristics ................................................................................ 53 2.6.2 MCC Tracks................................................................................................ 54 2.6.3 MCC Development...................................................................................... 55 2.6.4 MCC Satellite Examples............................................................................... 56 2.6.5 Flash Flooding............................................................................................. 56 2.7 Downburst ......................................................................................................... 57 2.7.1 Microburst................................................................................................... 57 2.7.2 Macroburst .................................................................................................. 63 2.7.3 Heat Burst .................................................................................................... 63 2.7.4 Radar and Visual Indicators.......................................................................... 64 Module 3 – Airmass Types and Thunderstorms............................................................. 69 3.0 Severe Synoptic Patterns ..................................................................................... 70 3.1. Type A Synoptic Pattern (Dryline) .................................................................... 70 3.1.1 Characteristics .............................................................................................. 70 3.1.2 Severe Weather............................................................................................. 70 3.2 Type B Synoptic Pattern (Frontal).................................................................... 72 3.2.1 Characteristics .............................................................................................. 72 3.3 Type C Synoptic Pattern (Overrunning) ............................................................. 74 3.3.1 Characteristics ............................................................................................. 75 3.3.2. Severe Weather........................................................................................... 75 3.4 Type D Synoptic Pattern (Cold Core)................................................................. 76 3.4.1. Features:..................................................................................................... 76 3.4.2. Severe Weather..........................................................................................
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