Weather For Dummies

John D. Cox is a professional science writer. He studied biological and physical sciences at Harvard and MIT, and served as a fellow of the Knight Science Journalism Fellowship Program at MIT.

Introduction 1


About This Book 1


Foolish Assumptions 2


How This Book is Organized 2


Part 1: What in the World is Weather? 3


Part 2: Braving the Elements 3


Part 3: Some Seasonable Explanations 4


Part 4: The Special Effects 4


Part 5: The Part of Tens 4


Appendix 5


Icons Used in This Book 5


Where to Go from Here 6


Part 1: What in the World is Weather? 7


Chapter 1: Forecasts and Forecasting 9


Forecasting Prophets 10


Making a Forecast 11


Take what is happening now 13


 And add a little future 14


“We Interrupt This Program ” 16


Water, Water, Everywhere 18


Flavors of Forecasts 18


Agricultural forecasts 19


Aviation forecasts 19


Marine forecasts 20


River forecasts 20


Fire forecasts 21


Keywords to the Wise 21


Precipitation 21


Temperature 23


Temperature’s relative humidity 24


Heat index 25


Wind 27


Wind chill 28


Sky cover 28


Tools of the Trade 29


The instruments 29


The instrument carriers 30


Doppler radar 32


A fleet of satellites 33


Computers 35


How to Read a Weather Map 36


Chapter 2: Behind the Air Wars 37


I Don’t Like Your Latitude! 37


Where the Armies Mass 39


Winter air masses 41


Summer air masses 42


News from the Fronts 42


Cold fronts 43


Warm fronts 43


Stationary fronts 44


Occluded fronts 44


Here Comes the Sun 45


Moving Sun’s energy 45


Looking absolutely radiant! 46


A contagious convection 49


The Big Picture 50


Long live the revolution! 50


Spreading the beam 51


Tilting at the seasons 53


Spin of the day 55


Putting on Airs 56


Do I smell gas? 56


How high the sky? 59


Chapter 3: Land, Sea, and Precipitation: is This Any Way to Run a Planet? 61


Water’s Stirring Role 62


Ocean to atmosphere 64


Atmosphere to surface 65


Surface to ocean 66


Rain to Rime: Forms of Precipitation 67


Rain 68


Snow 69


Hail 70


Graupel (snow pellets) 70


Sleet (ice pellet) 71


Rime 71


Dew to Fog: Forms of Condensation 72


Dew 72


Frozen dew 72


Frost 73


Fog: A grounded cloud 73


Weather and the Land 75


A lopsided planet 75


Radiating hot and cold 75


Air’s roller-coaster ride 76


Weather and the Ocean 77


Part 2: Braving the Elements 79


Chapter 4: Blowing in the Winds 81


Taking the Pressure 82


A World of Wind and Pressure 83


That muggy Bermuda High 85


That cool Pacific High 85


The winter lows 87


Bending the Winds 87


Taking the pressure — it’s a gas 87


Here’s the rub — total friction 89


A perfectly straight curveball 91


The Winds Aloft 94


The Westerlies 94


The Jet Streams 96


Polar jet stream 96


Subtropical jet stream 97


Low-level jets 97


The Tradewinds 97


A Scattering of Winds 98


Coastal breezes 99


Valley and mountain breezes 99


Asian monsoon 99


Southwestern monsoon 101


Chinooks 101


Santa Anas 101


Haboobs 102


Chapter 5: Getting Cirrus 103


Making Clouds: The Heavy Lifting 104


Heating up 104


Crowd control 105


Frontal assaults 105


Over the top 105


A Question of Stability 108


Clouds by Class 109


High clouds 110


Middle clouds 113


Low clouds 115


Vertical clouds 118


Special clouds 119


Clouds of the stratosphere 122


Chapter 6: Climate is What You Expect; Weather is What You Get 125


Climate or Weather? 126


Climates of the World 126


What Makes Climates Different? 128


Climate and the Seasons 130


A climate of mystery 130


“It’s the ocean, stupid” 132


Pacific Body Parts 132


The Warm Pool 133


The Cold Tongue 134


El Niño, His Cool Sister, and Their Kissing Cousins 134


Is El Niño a bad boy? 135


The El Niño look 135


La Niña, the contrary sister 138


The La Niña look 139


Climate’s kissing cousins 140


Climates of the Past 141


Long warm ages 142


Short ice ages 143


Medieval warm period 143


Little ice age 145


A warming trend 146


Chapter 7: The Greatest Storms On Earth 147


Breeding Grounds 148


Mysteries 150


Birth of a Hurricane 151


Disturbance to depression 152


Storm to hurricane 152


Bad big weapons 153


Storm surge 153


Winds 154


Tornadoes 155


Flooding rainfall 155


Signals of the seasons 156


Cruise’n for a Bruise’n 159


Satellites 159


Aircraft 160


Radar 160


Computer models 160


Coming Ashore But Where? 161


The Big Picture 161


Tracking the track 162


In Harm’s Way 163


Barrier islands 164


Playing it safe 165


The overwarning problem 165


Hurricane Force 166


Part 3: Some Seasonable Explanations 169


Chapter 8: The Ways of Winter 171


Winter’s “Official” First Day 172


It’s a Temperature Thing 173


Coast to Coast 174


Storms of Winter 177


A storm is born 178


Working out the wrinkles 179


Catching the waves 182


Riding the conveyor belt 182


Where They Come From 184


Where They Go 185


Name That Storm 187


Alberta Clipper 187


Hatteras bomb 187


Colorado Low 187


Gulf Low 188


Chattanooga Choo-choo 188


Nor’easter 188


Pineapple Express 190


Siberian Express 190


Panhandle Hook 190


Texas Panhandler 191


Blue Norther 191


When the Flakes Fly 191


Blizzards 194


Ice Storms 196


Life and Limb 197


Cold weather exposure 198


Frostbite 198


Caught in a car 199


Chapter 9: Twists and Turns of Spring 201


When Has Spring Sprung? 202


Coast to Coast 203


Thunderstorms 204


How exactly “severe”? 206


Shapes and sizes 207


Supercell 212


Hail the Size of Hailstones 214


Flash Floods 215


ZAP! Crack! Bam! 216


Rumbles and claps 218


Different strokes 219


Lightning safety tips 219


Downbursts 220


Really Twisted Winds 222


Tornado Alley 224


Forecasting 226


Lives and Limbs 228


A watch or a warning? 230


Tornado do’s — and nots! 230


Chapter 10: Extremely Summer 233


Good Ol’ Summer Timing 234


Coast to Coast 235


Avoiding That Radiant Feeling 238


The Heat is On 239


Heatwaves 241


Stranded on crowded islands 243


Storms of Summer 244


Out of Whack 246


When It Rains Too Much 247


When It Rains Too Little 250


Chapter 11: Falling for Autumn 255


The Timing Thing 256


Falling Highs and Lows 256


Coast to Coast 257


In a Pigment’s Eye 258


Indian Summer 259


In the Fogs 260


Fires of the Wild West 261


Part 4: The Special Effects 263


Chapter 12: Taking Care of the Air 265


Polluting the Air 266


The short and long of it 267


The usual suspects 268


Getting the drift 270


Acid rain 270


The Hole in the Sky 272


The ozone-eaters 273


On the mend? 274


The Big Warm 275


On the natural 276


On the unnatural 278


The global warming picture 279


The global warming debate 280


The heat is on 281


A splash of cold water 282


Wild and crazy 282


Chapter 13: Up in the Sky! Look! 285


Seeing the Light 286


In Living Color 287


Why the Sky is Blue 287


Reflecting on Clouds 288


Silver Linings 289


Blue Haze 290


Sunbeams 290


Sunrise, Sunset 291


The Green Flash 293


Rainbows 293


Haloes 295


Sun Dogs 296


Sun Pillars 296


Coronas 297


Glories 298


Mirages 298


Inferior mirage 299


Superior mirage 299


Twinkle, Twinkle Little Air 299


Auroras 300


Chapter 14: Try This at Home 301


You’re Not Just an Amateur 301


Galileo and the Boys 302


Galileo’s thermometer 303


Torricelli’s barometer 303


Cardinal de Cusa’s hygrometer 304


Early American Weathermen 304


George did it 305


Tom did it 305


Ben did it all 306


Watching Your Weather 307


Getting Fancy 307


Going instrumental 308


Going digital 309


Cool Weather Experiments 310


Making rainbows 310


Bending light by refraction 310


Bending light by diffraction 312


Weighing in on air 312


Testing the pressure 313


The greenhouse effect 313


Cloud in a can 314


A bottle of fog 314


Part 5: The Part of Tens 315


Chapter 15: Ten (or So) Biggest U.S Weather Disasters of the 20th Century 317


The Galveston Hurricane 318


The Dust Bowl 318


Super Tornado Outbreak, 1974 319


Hurricane Camille 319


The Great Midwest Flood 320


El Niño Episodes 320


Hurricane Andrew, 1992 321


New England Hurricane, 1938 321


Superstorm, March 1993 321


Tri-State Tornado, 1925 322


Tornado Outbreak of May 1999 322


The Great Okeechobee Flood and Hurricane of 1928 323


Florida Keys Hurricane, 1935 323


New England Blizzard, 1978 323


Storm of the Century, 1950 324


Chapter 16: Ten (or So) Worst World Weather Disasters of the 20th Century 325


Droughts 326


India 326


China 326


Soviet Union 326


Africa 327


Floods 327


China 327


Vietnam 327


Iran 327


Typhoons, Cyclones, and Hurricanes 327


Bangladesh 328


China 328


Honduras 328


Japan 328


Philippines 329


Winter Storms 329


Iran 329


Europe 329


Pollution 329


Donora 329


London 330


Chapter 17: Ten Crafty Critters 331


Cats 332


Dogs 332


Frogs 333


Ants 333


Birds 333


Caterpillars 334


Squirrels 334


Groundhog 335


Livestock 335


Fish 336


Chapter 18: Ten Grand Old Weather Proverbs 337


Red Sky at Night, Sailor’s Delight 338


Clear Moon, Frost Soon 338


Early Thunder, Early Spring 338


After Frost, Warm 339


Mare’s Tails and Mackerel Scales 339


Rainbow in the Morning 339


When Halo Rings the Moon 340


Rain Long Foretold 340


A Year of Snow, a Year of Plenty 340


In Like a Lion and Out Like a Lamb 341


Appendix: Internet Resource Directory 343


Index 351