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In stock

Instability, Skew-T and Hodograph Handbook
Tim Vasquez

2017 / 248 pp.
$38.95 / ISBN-10: 978-0-9969423-3-1

8 x 10" / True bound / Color / Glossy cover

Are you a forecaster who wants to know everything about upper-air observations, radiosondes, skew-T's, hodographs, and severe weather indices? Your holy grail is finally here! It's the skew-T and hodograph book that has been in the works since 2009, and announced 11/24/17.

Released in 2017 Instability, Skew-T, and Hodograph Handbook provides a full background on working with skew-T diagrams and hodographs. Math is kept to an absolute minimum, the text has a friendly tone, and the information starts out simple and then builds on the existing text. Learn how these diagrams work, what all the lines mean and how to use the charts. Nearly every known severe weather index is covered, including newer parameters like Significant Tornado Parameter and Critical Angle. Informative notes in the margin help clarify the material and provide related historical and technical background. Each chapter has a summary section and and 20 questions.

Chapters on skew-T diagrams and hodographs
The book starts out with a chapter on thermodynamics, followed by a grounding in observing systems, then proceeds to working with skew-T's and hodographs. The charts are explained in detail, with numerous case studies and forecaster notes.

Severe weather index spreads
For 23 of the most heavily used severe weather indexes, there is a two-page spread. This provides a definition of the index, how it was developed, the range of units that are typical for severe weather situations, and samples for about 15 recent tornado outbreaks, This makes an excellent go-to desk reference for anyone working up a severe weather prediction or a chase forecast.

Instability, Skew-T, and Shear Handbook is designed for forecasters, hobbyists, undergraduate college students, and anyone who wants to learn more.

Forecasters Reference Workbook is the companion to this title, and will help you work through its material or apply what you've learned to your forecasts.

Additionally, our laminated skew-T log-p diagram, with reference info authored by Tim Vasquez on the back, is a useful tool to accompany this book.

About the author

Tim Vasquez began a meteorology career in 1984 writing the weather page for a Dallas newspaper. From 1989 to 1998 he was an Air Force meteorologist and worked at two television stations. He developed the Digital Atmosphere weather analysis software system in use worldwide. Residing in Austin, Texas, he is a software programmer, a consulting meteorologist, and a columnist for Weatherwise magazine.

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1 | Thermodynamics / 1
1.1. The parcel / 1
1.2. Altitude / 1
1.3. Pressure / 3
1.4. Physical units / 6
1.5. Heat / 7
1.6. Phases of matter / 14
1.7. Phase changes / 15
1.8. Temperature / 16
1.9. Water / 19
1.10. The saturation process / 21
1.11. Moisture properties / 25
1.12. Troposphere and stratosphere / 28
2 | Observing systems / 35
2.1. History / 35
2.2. Balloons / 37
2.3. Pilot balloon / 38
2.4. Modern radiosondes / 39
2.5. Radar velocity data / 52
2.6. Wind profiler / 53
2.7. AMDAR / ACARS / MDCRS / 54
3 | Skew-T log-p diagram / 59
3.1. The skew-T log-p chart / 61
3.2. Construction of the skew-T / 61
3.3. Meteorological data / 64
3.4. Static stability and lapse rate / 66
3.5. Lifting / 73
3.6. Basic parcel properties / 76
3.7. Proximity sounding / 81
3.8. Parcel techniques / 82
3.9. Virtual temperature / 88
3.10. Dryline / 89
3.11. Capping inversion / 93
4 | Shear & hodograph / 99
4.1. Hodograph / 99
4.2. Shear / 100
4.3. Hodograph quantities / 103
4.4. Storm motion / 109
4.5. Storm-relative frame / 112
4.6. Shear and storm forecasting / 113
4.7. Helicity / 117
5 | Severe storm forecasting / 123
5.1. Storm types / 123
5.2. Elements / 125
5.3. Shear and instability / 128
5.4. The trigger / 132
5.5. Patterns / 132
A-1 -- Severe weather indices / 141
A1.1. The use of prediction schemes / 141
A1.2. Case study values / 142
A-2 -- SHARPpy / 195
A2.1. About SHARPpy / 195
A2.2. Concept of operation / 196
A2.3. Hodograph / 199
A2.4. Storm slinky / 199
A2.5. Equiv. potential temp. profile / 201
A2.6. Storm-relative wind profile / 203
A2.7. Possible Hazard Type / 204
A2.8. Thermodynamic output / 205
A2.9. Shear output / 208
A2.10. Sounding analogs (SARS) / 209
A2.11. Significant Tornado Parameter (STP) / 209
A-3 -- RAOB / 213
A3.1. Data import / 213
A3.2. RAOB soundings / 214
A3.3. RAOB hodograph / 216
A3.4. Cross section / 216
A3.5. Other features / 216
A-4 -- Other resources / 219
A4.1. University of Wyoming / 219
A4.2. UCAR weather / 220
A4.3. Storm Prediction Center / 221
A4.4. / 222
A4.5. ESRL RUC Soundings site / 223
A-5 -- Radiosonde data / 225
A-6 -- Glossary / 229
References / 233
Index / 239