Appendix 1Universal keywords (291)

Advice, Affordable, Alternative, Anniversary, Annually, Anthony, Application, Arena, Article, Assistance, AT&T, Athlete, Ball, Basketball, Beatingtheheat, Beattheheat, Bench, estAirConditioningContractor, Bestthingstobuy, Bonus, Boris, Bosh, Brandnew, Breakingnews, Bron, Brooklyn, Bryant, Bulls, Business, Buzzer, Calling, Capacitor, Career, Carinsurance, Carmelo, Center, Certifications, Certified, Championship, Checkitout, Checkout, Checkout, Checkthis, Checkthisout, Checkup, Checkups, Check-ups, Cheering, Click, Clippers, Comeby, Comeenjoy, Comeondown, Companies, Company, Competitive, Contact, Cost, Coupons, Court, Crampin, Creditcard, Customers, Customersatisfaction, Customerservice, Danny, David, Designer, Detailed, Details, Diagnostic, Diaw, Didyouknow, DidYouKnow, Discount, Donations, Doyouneed, Dub, Duncan, Dunk, Durant, Dwill, Efficiency, Efficiently, Enternow, Episode, Equipment, Espn, Evan, Experienced, Facts, Fake, fans, Federal, Followme, Followus, Forward, Game, Garnett, Gatorade, George, Giftcard, Greatprice, Green, Guard, Half, Hatingontheheat, Heatfan, Heathaters, HeatLose, HeatNation, Heatseries, Hibbert, Highlight, Highquality, Hiring, Improve, Industry, Inexpensively, Information, Inspection, Installation, Insurance, Interested, Introducing, Invoice, James, Jobs, Joinus, Jordan, Kawhi, KevGarnet, Kobe, Lakers, Lance, LBJ, Leaders, Learnmore, Lebitch, Leonard, Letsgo#heats, Letsgoheat, Letsgoheat, Lifetime, Limitedtime, Listing, Lose, Lost, Luis, Maintenance, Manu, Marketing, Mechanic, Mechanical, Melo, Membership, MIA, Miami, Model, Moneysaver, Monitor, Moreinfo, Mostrefreshinginfo, Mustwatch, NBA, Needhelp, Net, Newblog, Newjob, Newpost, News, Niche, Notafanofheat, Offer, OilChanges, OKC-HEAT, Onspecial, Opening, Overview, Pacers, Packingheat, Packinheat, Parker, Parts, Paul, Performance, Pierce, Platform, Played, Player, Playoffs, Plumber, Point, Pop, Preorder, Pricereduction, product, Professional, Promo, Protip, Quarter, Question, Quote, Raiseawareness, Ray, Readmore, Realestatemarket, Rebate, Recruiting, Refreshinginfo, Refund, Reinstall, Release, Reminder, Rentalmarket, Repair, Replacement, Retailer, Review, Riley, Roy, RT, Sale, SanAntonio, Savecash, Scams, Scientist, Scola, Seasonal, Seasonbegins, Secondround, Selling, Series, Services, Sharing, Shipping, Solutions, Specials, Sponsored, Sport, Spur, Stat, Stephenson, Stephenson, Sterling, Steroids, Stopby, Strategies, Subscriber, Superbowl, Supervisor, Support, System, TaunTaun, Tauntaun, Team, Technician, Technique, Threepeat, Thunderandheat, ThunderNation, Tickets, Timmy, Tips, Titles, Tony, Topproducers, Training, Transmission, Turner, Turnovers, Unbeatable, Updateon, Upgrade, Up-to-date, VanGundy, Vehicleaccident, Video, Wade, Washingtonpost, Waysto, West, Whatyouneedtoknow, Win, Wizards, Wordoftheday, Yourairconditioningsystem, 3 peat, 3Peat

Appendix 2Theme specific keywords

(a) AC(79)
Audi, ACCA, Ace mechanical, Acura, Air conditioning service, Air leaks, All temperature is here to meet all your, Bentley, BMW, Bugatti, Buick, Cadillac, Chevrolet, Chevy, Chrysler, Compressor Breakdowns, Condenser Coil, Dodge, Ductless, Engine, Ferrari, Fiat, Filter change, Ford, Furnace, GMC, Have you considered any special features, Honda, How Air Conditioning Remade Modern America, How to maintain your A/C, Hummer, Hyundai, I woke up and my eyebrows were frozen, If I had been a caveman, Infiniti, Isuzu, Jaguar, Jeep, Lamborghini, Land Rover, Left the air conditioning on in the bus last night, Lexus, Lincoln, Maintaining your HVAC equipment, Maybach, Mazda, Mercedes Benz, Mini, Mitsubishi, Motor, Mustang, Nissan, Owner, Peugeot, Plumbing, Porsche, Refrigerant, Regulations, Renault, Replacing your AC unit, Rolls Royce, Roommate Wanted, Saab, Scion, Skyrocket, Stands for, Stop Your Air Conditioner Leaking Water, Subaru, Suzuki, Suzuki, Tesla, The problem with air conditioning in vehicles, Thieves, Toyota, Volkswagen, Volvo, Web pro, Wheels, Zoning technology
(b) Dehydration (116)
Active measures, Alcohol, Alert, Almond, Animal, Antibiotics, Apple, Are you experiencing, Avoid chronic, B.B. King, Banana, Barley, Be active and safe, Beef, Beer, Being dehydrated can cause a decrease in your mental function, Berries, Beverage, Bull, Caffeine, Camping food, Cancer, Carrot, Cats, Cheese, Chicken, Chili, Chocolate, Coffee, Concert, Cramps, Cry, Dancing, Dandruff, Diabetes, Dogs, Drink some water after you wake up, Drunk people, Fat and sick, Flake, Food, Fruit, Garlic, Genome, Hair, Hangover, Hearing loss, Herb, Hungover, If you are hungry after eating recently, If you feel tired even, If you suffer from dry, If you woke up with a headache, If you're hungry 30 minutes after a meal, Infection, Ingredient, Jellyfish, Jimmie Johnson, Johnson, Keep calm and drink water, Lizard, Maple, Marshmallow, Meals, Meat, Milk, Miso, Muscle, Mushroom, Nightmare, Noodle, Ole girl isn't even thirsty, Onion, Orange, Organic, Pasta, Pineapple, Pizza, Plum, Poisoning, Pork, Potato, Powdered, Preserve, Prevention, Product, Prune, Reasons Dehydration Is Making You Sick And Fat, Recipe, Salad, Salt, Sauce, Sex, She ain't even thirsty she dehydrated, She isn't even thirsty bruh, she's dehydrated, She's not even thirsty... She's dehydrated, Shrimp, Skin, Soup, Space food, Starving? But you just ate an hour ago?, Stomach virus, Sugar, Surprising Causes of Dehydration, Tacos, Tears, Tipsy, Tomato, Unusual signs, Vegetable, Veggies, Vital questions, Vodka, Wrinkle, 3 signs
(c) Electrical outage (22)
Affected, Affects, Amusement park, Bird, Brown Sabbath, cats, Cedar Park, Disney, Electrical fire, Entertainment, Essex Power, How to Get Out of Your Own Way and Unblock the, Investigating, Planned, Scheduled, Seaworld, Six Flags, Squirrel, Subway, Theme park, What to do with the food in your fridge after a power outage, When the electricity goes out in your home
(d) Heat (98)
Advisory, Album, All temperature is here to meet all, Are you ready for the heat, Artist, Baking, Beat, Beef, Bit, Blowdryer, Box office, Box set, Brain, Carrot, Cheese, Chicken, Chili, Chocolate, Computer, Cook, Desktop, Diamond, Disease, Donation, Download, Engine, Featuring, Flash drive, Food, fruits, Frying pan, Garlic, Geothermal, Geo-thermal, Global warming, Hard drivers, Heat transfer, Heat warning, Heet district, He'll raisin' heat of the summer, Herb, Husky was a little, I'm overheat for you, In the heat of the moment, Ingredient, Ipod, Itunes, Jazz, Laptop, Listen, Macbook, Maple, Marshmallow, Meals, Meat, Microwave, Miso, Mixtape, Mushrooms, Music, New heat, New single, New summer heat, Noodle, Onion, Organic, Oven, Overheated market, Pasta, Phone, Pizza, Playing, Playlist, Pork, Potato, Power adapter, Pump, Record, Rock, Server, Set the club on fire, Shrimp, Sin city, Snoop Dogg, Solstice, Song, Soup, Summer heat gets even hotter, Tacos, Tomatoes, Track, Trailer, Vegetable, Veggies, Warning, Weather service, Xbox, You're the heat that I know

Appendix 3Filtering keywords characteristics

Theme / Characteristics / Examples
AC / advertisement, job postings, automobile brand, automobile part /

technician, engineer, Ford, A/C Compressors

Dehydration / animal, food and ingredient, reasons / dog, cat, vegetables, alcoholic beverage, exercise, caffeine, sexual behaviors
Electrical outage / announcement, news, reasons / expected blackout, amusements parks and certain facilities or location, bird, squirrel
Heat / product, food, music / overheated PC, baking, heat music

Appendix 4Summary of top 50 cities

City Name / Latitude / Longitude / AC / Dehydration / Electrical outage / Heat / Sum
1 / Los Angeles, CA / 34.1 / -118.2 / 3704 / 1055 / 888 / 9620 / 15267
2 / New York, NY / 40.7 / -74.0 / 4341 / 1136 / 572 / 7110 / 13159
3 / Chicago, IL / 41.9 / -87.6 / 2886 / 871 / 717 / 4567 / 9041
4 / Houston, TX / 29.8 / -95.4 / 1939 / 554 / 334 / 4090 / 6917
5 / Atlanta, GA / 33.7 / -84.4 / 1328 / 403 / 252 / 2843 / 4826
6 / Las Vegas, NV / 36.2 / -115.1 / 1163 / 327 / 196 / 2839 / 4525
7 / San Diego, CA / 32.7 / -117.2 / 1070 / 325 / 260 / 2484 / 4139
8 / Washington DC / 38.9 / -77.0 / 1432 / 263 / 329 / 2041 / 4065
9 / Boston, MA / 42.4 / -71.1 / 1265 / 380 / 225 / 2112 / 3982
10 / Seattle, WA / 47.6 / -122.3 / 1235 / 353 / 438 / 1910 / 3936
11 / Dallas, TX / 32.8 / -96.8 / 1093 / 311 / 392 / 2053 / 3849
12 / Miami, FL / 25.8 / -80.2 / 969 / 291 / 143 / 2235 / 3638
13 / Philadelphia, PA / 40.0 / -75.2 / 1012 / 287 / 262 / 2038 / 3599
14 / Austin, TEXAS / 30.3 / -97.7 / 1081 / 272 / 264 / 1769 / 3386
15 / San Francisco, CA / 37.8 / -122.4 / 905 / 268 / 331 / 1542 / 3046
16 / Phoenix, AZ / 33.4 / -112.1 / 774 / 191 / 183 / 1457 / 2605
17 / Portland, OR / 45.5 / -122.7 / 800 / 207 / 239 / 1098 / 2344
18 / Saint Louis, MO / 38.6 / -90.2 / 660 / 165 / 204 / 1296 / 2325
19 / San Antonio, TX / 29.4 / -98.5 / 634 / 200 / 152 / 1334 / 2320
20 / New Orleans, LA / 30.0 / -90.1 / 552 / 191 / 173 / 1292 / 2208
21 / Orlando, FL / 28.5 / -81.4 / 692 / 159 / 106 / 1222 / 2179
22 / Pittsburgh, PA / 40.4 / -80.0 / 721 / 194 / 183 / 972 / 2070
23 / Nashville, TN / 36.2 / -86.8 / 562 / 148 / 130 / 839 / 1679
24 / Baltimore, MD / 39.3 / -76.6 / 495 / 130 / 101 / 878 / 1604
25 / Denver, CO / 39.7 / -105.0 / 448 / 174 / 123 / 820 / 1565
26 / Sacramento, CA / 38.6 / -121.5 / 446 / 101 / 74 / 768 / 1389
27 / Tampa, FL / 28.0 / -82.5 / 403 / 94 / 114 / 725 / 1336
28 / Detroit, MI / 42.3 / -83.0 / 404 / 95 / 161 / 656 / 1316
29 / Minneapolis, MN / 45.0 / -93.3 / 474 / 110 / 113 / 609 / 1306
30 / Cleveland, OH / 41.5 / -81.7 / 437 / 112 / 117 / 611 / 1277
31 / Charlotte, NC / 35.2 / -80.8 / 368 / 77 / 74 / 745 / 1264
32 / Indianapolis, IN / 39.8 / -86.2 / 410 / 96 / 157 / 596 / 1259
33 / Memphis, TN / 35.1 / -90.0 / 335 / 94 / 155 / 657 / 1241
34 / Cincinnati, OH / 39.1 / -84.5 / 398 / 81 / 120 / 600 / 1199
35 / Columbus, OH / 40.0 / -83.0 / 433 / 102 / 133 / 523 / 1191
36 / Milwaukee, WI / 43.0 / -87.9 / 383 / 96 / 127 / 551 / 1157
37 / Tucson, AZ / 32.2 / -110.9 / 290 / 85 / 109 / 608 / 1092
38 / Louisville, KY / 38.3 / -85.8 / 290 / 60 / 81 / 500 / 931
39 / Raleigh, NC / 35.8 / -78.6 / 306 / 62 / 69 / 464 / 901
40 / Oklahoma City, OK / 35.5 / -97.5 / 273 / 64 / 68 / 441 / 846
41 / San Jose, CA / 37.3 / -121.9 / 203 / 65 / 65 / 477 / 810
42 / Fresno, CA / 36.7 / -119.8 / 159 / 63 / 28 / 511 / 761
43 / Orange, CA / 33.8 / -117.9 / 218 / 53 / 66 / 418 / 755
44 / Long Beach, CA / 33.8 / -118.2 / 181 / 32 / 40 / 492 / 745
45 / Fort Worth, TX / 32.8 / -97.3 / 235 / 55 / 84 / 361 / 735
46 / Jacksonville, FL / 30.3 / -81.7 / 216 / 59 / 41 / 401 / 717
47 / Richmond, VA / 37.5 / -77.4 / 217 / 33 / 52 / 381 / 683
48 / Buffalo, NY / 42.9 / -78.9 / 250 / 51 / 41 / 336 / 678
49 / Kansas City, KS / 39.1 / -94.6 / 186 / 47 / 50 / 356 / 639
50 / Tempe, AZ / 33.4 / -111.9 / 216 / 49 / 47 / 319 / 631

Appendix 5.The distribution of the tweets of 2,216 cities

Appendix 6The distribution of the normalized number of tweets with population (number of tweets per 100,000 people). Only cities having more than 50 tweets for each theme were selected

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