RANKING · 2022 ACS · 500 SHOWN OF 3,144

Most people vulnerable to extreme heat, US counties

US counties ranked by the estimated number of people with three or more heat-related social-vulnerability risk factors in 2022, from the Census Bureau's experimental Community Resilience Estimates for Heat (experimental, modeled data). Los Angeles County, California leads at 2,956,807. 3,144 counties qualify in total. California carries 8 of the top 25 entries. The median across all 3,144 is 7,386.

All statesAll rankings

SAME RANKING BYStates

RANKPLACESTATEPOPRESIDENTS VULNERABLE TO EXTREME HEATVS –

USUnited States331,097,5933,884,001–

01Los Angeles County, CACA9,694,9342,956,807–

02Cook County, ILIL5,194,6251,344,491–

03Harris County, TXTX5,045,0261,243,399–

04Maricopa County, AZAZ4,689,558952,753–

05Kings County, NYNY2,653,963936,488–

06Orange County, CACA3,149,507837,526–

07Miami-Dade County, FLFL2,802,029809,872–

08San Diego County, CACA3,282,248800,809–

09Queens County, NYNY2,358,182781,433–

10Riverside County, CACA2,544,916670,517–

11Dallas County, TXTX2,661,397657,556–

12Bronx County, NYNY1,406,332633,751–

13King County, WAWA2,344,939630,309–

14San Bernardino County, CACA2,224,091593,594–

15New York County, NYNY1,664,862586,444–

16Clark County, NVNV2,407,226559,633–

17Santa Clara County, CACA1,914,391547,445–

18Bexar County, TXTX2,160,088519,489–

19Broward County, FLFL2,013,317511,438–

20Philadelphia County, PAPA1,574,281487,126–

21Wayne County, MIMI1,769,038475,641–

22Alameda County, CACA1,636,630470,197–

23Tarrant County, TXTX2,248,466462,417–

24Palm Beach County, FLFL1,575,726414,241–

25Sacramento County, CACA1,618,460402,937–

26Contra Costa County, CACA1,170,070352,455–

27Hillsborough County, FLFL1,574,115345,220–

28Fresno County, CACA1,035,456322,176–

29Cuyahoga County, OHOH1,232,925315,477–

30Suffolk County, NYNY1,546,090311,100–

31Orange County, FLFL1,528,002309,167–

32Hidalgo County, TXTX921,549306,768–

33Middlesex County, MAMA1,669,979305,447–

34Nassau County, NYNY1,398,939299,932–

35El Paso County, TXTX877,858294,680–

36Kern County, CACA927,068288,281–

37Pima County, AZAZ1,074,685288,117–

38Franklin County, OHOH1,361,536284,991–

39Honolulu County, HIHI988,703277,902–

40San Francisco County, CACA826,079272,933–

41Allegheny County, PAPA1,225,035263,116–

42Pinellas County, FLFL948,563259,946–

43Essex County, NJNJ896,379253,301–

44Ventura County, CACA830,851252,324–

45Travis County, TXTX1,389,670252,182–

46Westchester County, NYNY1,015,743248,581–

47Erie County, NYNY946,741243,713–

48Hennepin County, MNMN1,284,784235,709–

49Prince George's County, MDMD970,374232,885–

50San Mateo County, CACA743,568232,221–

51Shelby County, TNTN910,226229,893–

52Suffolk County, MAMA791,891229,667–

53Pierce County, WAWA946,288229,009–

54Oakland County, MIMI1,288,337228,442–

55Milwaukee County, WIWI924,216227,872–

56Lee County, FLFL875,607225,070–

57Duval County, FLFL1,062,963223,139–

58Snohomish County, WAWA870,656220,796–

59Bergen County, NJNJ977,026220,246–

60Marion County, ININ992,196220,139–

61Hudson County, NJNJ735,033217,823–

62Montgomery County, MDMD1,074,582216,986–

63San Joaquin County, CACA823,815215,459–

64Fulton County, GAGA1,098,791210,289–

65Mecklenburg County, NCNC1,233,383210,110–

66Polk County, FLFL874,790209,741–

67Capitol Planning Region, CTCT994,115208,221–

68St. Louis County, MOMO990,911205,573–

69Middlesex County, NJNJ883,335197,381–

70Essex County, MAMA826,653190,006–

71Multnomah County, OROR795,391189,780–

72Oklahoma County, OKOK822,125188,428–

73Wake County, NCNC1,257,235188,370–

74Gwinnett County, GAGA1,018,099186,579–

75Salt Lake County, UTUT1,220,916185,491–

76Monroe County, NYNY750,506184,847–

77Fairfax County, VAVA1,167,873184,259–

78Hamilton County, OHOH838,418183,562–

79Macomb County, MIMI886,221181,214–

80Baltimore County, MDMD847,650181,117–

81Worcester County, MAMA888,502178,857–

82Collin County, TXTX1,297,179175,895–

83Jefferson County, KYKY795,222172,997–

84DeKalb County, GAGA774,394170,011–

85DuPage County, ILIL934,298168,923–

86Fort Bend County, TXTX975,191167,934–

87Stanislaus County, CACA557,719166,586–

88Bernalillo County, NMNM667,601166,121–

89Jefferson County, ALAL665,742165,946–

90Baltimore, MDMD569,997163,915–

91Ocean County, NJNJ673,746163,789–

92Tulsa County, OKOK698,782163,591–

93Denton County, TXTX1,069,346163,332–

94Monterey County, CACA433,729162,485–

95District of Columbia, DCDC693,645161,459–

96Jackson County, MOMO732,994160,622–

97Providence County, RIRI678,179158,278–

98Union County, NJNJ601,863157,011–

99Montgomery County, PAPA877,643155,843–

100Davidson County, TNTN745,904155,227–

101Sonoma County, CACA486,444154,315–

102Passaic County, NJNJ531,624151,402–

103Brevard County, FLFL663,982151,073–

104Pasco County, FLFL674,516147,355–

105Volusia County, FLFL606,573147,304–

106Norfolk County, MAMA739,749145,548–

107Denver County, COCO740,613144,200–

108Tulare County, CACA485,146143,435–

109Cameron County, TXTX433,946142,441–

110Santa Barbara County, CACA442,065142,124–

111Washoe County, NVNV509,386140,884–

112Richmond County, NYNY501,290138,108–

113Montgomery County, TXTX781,194133,871–

114Spokane County, WAWA558,344132,638–

115Cobb County, GAGA793,345132,388–

116South Central Connecticut Planning Region, CTCT578,741130,245–

117Camden County, NJNJ535,799130,234–

118Lancaster County, PAPA563,159129,752–

119Bristol County, MAMA593,640129,649–

120Washington County, OROR611,708129,437–

121Western Connecticut Planning Region, CTCT640,482129,320–

122Lake County, ILIL719,339129,046–

123Kent County, MIMI675,232127,793–

124Pinal County, AZAZ539,380127,690–

125Sarasota County, FLFL479,958127,192–

126Solano County, CACA455,376127,101–

127El Paso County, COCO757,040124,206–

128Guilford County, NCNC562,234123,283–

129Monmouth County, NJNJ651,035123,201–

130Hampden County, MAMA464,338123,183–

131Clark County, WAWA532,119122,494–

132Delaware County, PAPA580,937122,337–

133Montgomery County, OHOH539,598121,356–

134Will County, ILIL712,253120,542–

135Ramsey County, MNMN541,623120,363–

136Bucks County, PAPA647,828120,322–

137Arapahoe County, COCO673,820119,819–

138Lake County, ININ504,612118,428–

139Collier County, FLFL417,131117,552–

140Marion County, FLFL442,660117,265–

141Manatee County, FLFL468,200116,465–

142Onondaga County, NYNY466,584115,774–

143Summit County, OHOH538,376115,350–

144Douglas County, NENE606,460114,270–

145Williamson County, TXTX752,827114,041–

146New Castle County, DEDE588,026113,712–

147Sedgwick County, KSKS538,433112,593–

148Jefferson County, COCO580,451112,562–

149Jefferson Parish, LALA431,398111,409–

150East Baton Rouge Parish, LALA456,180111,281–

151Mobile County, ALAL411,658110,068–

152Lane County, OROR381,584107,922–

153Adams County, COCO554,668106,911–

154Lake County, FLFL456,068105,873–

155Horry County, SCSC427,551105,639–

156Greenville County, SCSC583,125105,436–

157Plymouth County, MAMA546,829104,071–

158Placer County, CACA442,081103,874–

159Pulaski County, ARAR404,611103,127–

160Orleans Parish, LALA362,154103,024–

161Clackamas County, OROR426,280102,198–

162Naugatuck Valley Planning Region, CTCT463,349100,901–

163Kane County, ILIL525,757100,317–

164Berks County, PAPA440,07299,983–

165Knox County, TNTN511,45399,940–

166Osceola County, FLFL481,71899,874–

167Nueces County, TXTX352,99298,867–

168Lucas County, OHOH423,34798,845–

169Anne Arundel County, MDMD603,38098,577–

170Marion County, OROR355,77798,392–

171Dane County, WIWI590,37597,674–

172Orange County, NYNY417,66997,284–

173Bell County, TXTX402,24896,435–

174Rockland County, NYNY357,39796,093–

175Seminole County, FLFL491,88495,944–

176Mercer County, NJNJ399,28994,395–

177Yavapai County, AZAZ252,55293,795–

178Merced County, CACA297,26093,507–

179St. Lucie County, FLFL402,44993,041–

180Utah County, UTUT759,85992,774–

181Genesee County, MIMI401,09392,474–

182Morris County, NJNJ524,25191,998–

183Lehigh County, PAPA384,38391,457–

184Santa Cruz County, CACA258,85291,404–

185Burlington County, NJNJ481,43990,990–

186Larimer County, COCO377,29290,679–

187Johnson County, KSKS636,90690,654–

188Anchorage, AKAK287,15590,209–

189Polk County, IAIA516,54689,727–

190San Luis Obispo County, CACA282,36789,474–

191Luzerne County, PAPA332,12689,350–

192York County, PAPA473,19788,299–

193Hawaii County, HIHI210,04388,259–

194Greater Bridgeport Planning Region, CTCT337,69788,035–

195Richland County, SCSC434,95687,500–

196Charleston County, SCSC436,20086,538–

197Galveston County, TXTX372,20786,321–

198Chester County, PAPA557,11686,299–

199Forsyth County, NCNC401,71886,250–

200Marin County, CACA253,69486,235–

201Ada County, IDID546,14185,182–

202Virginia Beach, VAVA453,73784,104–

203Hamilton County, TNTN390,83383,990–

204Madison County, ALAL433,51683,560–

205Webb County, TXTX281,22482,826–

206Westmoreland County, PAPA349,32481,870–

207Brazoria County, TXTX419,08081,288–

208Spartanburg County, SCSC380,85780,898–

209Allen County, ININ402,32980,638–

210Stark County, OHOH373,77178,962–

211Lubbock County, TXTX328,90678,904–

212Mohave County, AZAZ228,10278,440–

213Yakima County, WAWA259,18578,286–

214Thurston County, WAWA304,26177,983–

215Buncombe County, NCNC277,41777,736–

216Prince William County, VAVA502,96677,432–

217Kitsap County, WAWA283,37475,803–

218St. Louis, MOMO278,14475,682–

219Albany County, NYNY321,22575,594–

220Washtenaw County, MIMI370,21474,677–

221Escambia County, FLFL333,83474,631–

222Butler County, OHOH400,12874,457–

223Hillsborough County, NHNH433,41573,615–

224Sussex County, DEDE277,14073,521–

225Cumberland County, NCNC338,47373,487–

226Jefferson County, TXTX254,32172,248–

227Boulder County, COCO328,56072,232–

228Lorain County, OHOH323,21971,110–

229Doña Ana County, NMNM229,09170,606–

230Erie County, PAPA265,83270,053–

231Caddo Parish, LALA224,22669,990–

232Dakota County, MNMN457,71069,976–

233Chatham County, GAGA311,85569,823–

234Whatcom County, WAWA236,39269,590–

235McLennan County, TXTX272,02069,099–

236Clayton County, GAGA297,47168,523–

237Greene County, MOMO309,28668,388–

238Yuma County, AZAZ224,44967,688–

239Rutherford County, TNTN386,35267,639–

240Jackson County, OROR221,79567,307–

241Northampton County, PAPA324,41166,582–

242Imperial County, CACA181,41166,389–

243Fayette County, KYKY329,75166,191–

244Smith County, TXTX252,54965,970–

245Durham County, NCNC347,24065,863–

246Oneida County, NYNY226,39265,809–

247Atlantic County, NJNJ278,65765,723–

248Lexington County, SCSC317,58865,570–

249Weld County, COCO378,42665,443–

250Butte County, CACA209,21165,434–

251Winnebago County, ILIL283,67465,182–

252Dauphin County, PAPA293,35164,888–

253Charlotte County, FLFL217,21264,651–

254Leon County, FLFL299,04864,131–

255Dutchess County, NYNY300,70863,315–

256Baldwin County, ALAL267,76163,201–

257Somerset County, NJNJ356,48663,144–

258Anoka County, MNMN381,60562,890–

259St. Charles County, MOMO426,49962,666–

260St. Tammany Parish, LALA279,10862,588–

261Waukesha County, WIWI417,21062,548–

262Southeastern Connecticut Planning Region, CTCT284,01562,250–

263Washington County, UTUT213,67062,235–

264Henrico County, VAVA342,77562,186–

265Chesterfield County, VAVA397,14862,089–

266Brown County, WIWI275,80361,466–

267Shasta County, CACA181,64861,437–

268Lafayette Parish, LALA257,94961,434–

269Hinds County, MSMS211,88861,349–

270Montgomery County, ALAL225,89160,800–

271Ingham County, MIMI289,70960,149–

272Alachua County, FLFL290,02859,115–

273Cleveland County, OKOK303,97358,966–

274Barnstable County, MAMA233,53958,798–

275Lackawanna County, PAPA216,50258,770–

276St. Clair County, ILIL250,70858,607–

277Washington County, ARAR271,21358,264–

278St. Joseph County, ININ272,86158,081–

279Cumberland County, MEME317,22258,057–

280Harrison County, MSMS217,13657,715–

281Davis County, UTUT381,22757,591–

282Lancaster County, NENE334,04957,422–

283Citrus County, FLFL171,66656,799–

284Mahoning County, OHOH224,70656,705–

285Yolo County, CACA224,41056,608–

286Benton County, ARAR332,55456,524–

287Canyon County, IDID275,12356,247–

288Deschutes County, OROR213,07256,181–

289Santa Fe County, NMNM156,90756,158–

290Douglas County, COCO399,39655,768–

291Richmond, VAVA237,25755,662–

292Broome County, NYNY195,73655,542–

293El Dorado County, CACA192,32355,487–

294Tuscaloosa County, ALAL241,36854,926–

295Madison County, ILIL263,11054,809–

296Gloucester County, NJNJ312,63854,366–

297Brazos County, TXTX249,08854,283–

298Hernando County, FLFL221,70154,221–

299Rockingham County, NHNH324,07754,075–

300St. Louis County, MNMN200,51853,946–

301Weber County, UTUT278,17453,711–

302Niagara County, NYNY208,91253,665–

303Elkhart County, ININ208,77453,628–

304Anderson County, SCSC219,93053,488–

305St. Johns County, FLFL346,32853,312–

306Pueblo County, COCO169,27753,302–

307Madera County, CACA167,92753,238–

308Howard County, MDMD339,18352,855–

309Cumberland County, PAPA277,27052,771–

310Hays County, TXTX304,39052,681–

311Norfolk, VAVA231,01352,561–

312Calcasieu Parish, LALA208,46652,456–

313Navajo County, AZAZ109,94652,450–

314Ottawa County, MIMI308,45952,346–

315San Juan County, NMNM120,34052,048–

316York County, SCSC306,88752,033–

317Johnston County, NCNC256,44851,814–

318Trumbull County, OHOH198,97251,790–

319Loudoun County, VAVA449,74951,765–

320Kalamazoo County, MIMI263,79551,091–

321Muscogee County, GAGA202,17151,011–

322Beaufort County, SCSC204,43350,931–

323Benton County, WAWA221,72250,900–

324Gaston County, NCNC246,55850,875–

325Ulster County, NYNY183,33050,747–

326McHenry County, ILIL317,75149,895–

327Berkeley County, SCSC274,66649,548–

328Sumter County, FLFL157,77248,951–

329Richmond County, GAGA206,55948,932–

330Washington County, PAPA210,80248,927–

331Indian River County, FLFL172,79948,917–

332Saratoga County, NYNY241,34348,806–

333Harford County, MDMD266,44648,587–

334Lake County, OHOH232,21748,355–

335Ector County, TXTX173,80148,288–

336Ouachita Parish, LALA158,54248,058–

337Chesapeake, VAVA255,33248,002–

338Humboldt County, CACA131,64747,958–

339Saginaw County, MIMI187,68847,955–

340Aiken County, SCSC181,51547,905–

341Coconino County, AZAZ144,36847,779–

342York County, MEME222,43447,718–

343Hall County, GAGA226,56847,673–

344Frederick County, MDMD302,88347,292–

345Mesa County, COCO162,84547,074–

346New Hanover County, NCNC245,95946,810–

347Kootenai County, IDID191,86446,499–

348Champaign County, ILIL209,97246,442–

349Skagit County, WAWA132,97546,364–

350Kanawha County, WVWV172,38146,136–

351Muskegon County, MIMI177,90146,130–

352Hamilton County, ININ387,03645,573–

353Cherokee County, GAGA299,27345,562–

354Cochise County, AZAZ126,33245,056–

355Johnson County, TXTX218,04844,164–

356Cabarrus County, NCNC249,72544,158–

357Kings County, CACA154,32743,897–

358Henry County, GAGA264,92243,783–

359Brunswick County, NCNC174,70243,736–

360Robeson County, NCNC119,94143,496–

361Ellis County, TXTX240,86743,463–

362Comal County, TXTX209,16643,409–

363Bay County, FLFL204,47943,348–

364Sullivan County, TNTN163,75943,250–

365Butler County, PAPA200,16943,140–

366Bibb County, GAGA157,55642,816–

367Jefferson County, MOMO233,13242,765–

368Vanderburgh County, ININ181,99542,743–

369Martin County, FLFL166,27242,405–

370Shelby County, ALAL238,55241,993–

371Kent County, DEDE194,78641,971–

372Montgomery County, TNTN249,93541,929–

373Clay County, MOMO265,03241,887–

374Iredell County, NCNC211,79841,835–

375Penobscot County, MEME157,96741,752–

376Sandoval County, NMNM159,56541,716–

377Clay County, FLFL239,59341,652–

378Lee County, ALAL189,88141,539–

379Peoria County, ILIL178,55341,391–

380Union County, NCNC267,67441,388–

381Davidson County, NCNC180,18241,345–

382Washington County, MNMN286,89541,297–

383Tangipahoa Parish, LALA141,34641,269–

384Shawnee County, KSKS178,60741,186–

385Wyandotte County, KSKS170,59741,135–

386Monroe County, PAPA167,17941,077–

387Pitt County, NCNC182,93640,983–

388Douglas County, OROR111,95140,968–

389Okaloosa County, FLFL221,81040,918–

390Napa County, CACA132,94940,697–

391Maui County, HIHI160,59240,627–

392Chautauqua County, NYNY124,12640,461–

393Linn County, OROR132,84340,355–

394Newport News, VAVA183,23039,996–

395Alamance County, NCNC186,17739,974–

396Midland County, TXTX187,85539,936–

397Sumner County, TNTN215,53839,886–

398Schenectady County, NYNY162,58139,567–

399Linn County, IAIA232,02839,524–

400Florence County, SCSC138,50439,514–

401Jackson County, MSMS147,66639,440–

402Guadalupe County, TXTX201,11139,390–

403Centre County, PAPA157,39339,285–

404Sangamon County, ILIL194,17039,274–

405Randolph County, NCNC149,51638,590–

406Arlington County, VAVA243,93138,261–

407Beaver County, PAPA166,03238,095–

408Berrien County, MIMI152,44437,893–

409Cumberland County, NJNJ157,14837,847–

410Franklin County, PAPA160,65237,839–

411Kaufman County, TXTX209,23537,767–

412Williamson County, TNTN272,06137,673–

413Racine County, WIWI198,91937,652–

414Cambria County, PAPA128,96837,635–

415Clermont County, OHOH216,97737,425–

416Fayette County, PAPA123,02137,406–

417Rensselaer County, NYNY160,51037,302–

418Highlands County, FLFL111,12237,246–

419Onslow County, NCNC217,17537,239–

420Matanuska-Susitna, AKAK118,66637,207–

421St. Clair County, MIMI160,48637,204–

422Merrimack County, NHNH158,07837,025–

423Jackson County, MIMI159,55236,986–

424Schuylkill County, PAPA145,08536,861–

425Licking County, OHOH185,56436,689–

426McKinley County, NMNM68,11936,606–

427DeSoto County, MSMS197,91836,412–

428Rowan County, NCNC155,09636,284–

429Nevada County, CACA101,91136,191–

430Lebanon County, PAPA146,38035,911–

431Henderson County, NCNC122,37535,895–

432Catawba County, NCNC170,17235,729–

433Santa Rosa County, FLFL211,11535,707–

434Harnett County, NCNC150,13735,688–

435Wayne County, NCNC122,27835,669–

436Grayson County, TXTX153,61335,501–

437Tippecanoe County, ININ190,45635,411–

438Rapides Parish, LALA125,87735,330–

439Oswego County, NYNY118,56935,229–

440Warren County, OHOH257,18134,828–

441Rankin County, MSMS162,18134,764–

442St. Lawrence County, NYNY105,48834,698–

443Washington County, MDMD157,73134,414–

444Minnehaha County, SDSD212,69134,374–

445Parker County, TXTX184,76734,316–

446Taylor County, TXTX150,07734,293–

447Gregg County, TXTX126,09534,269–

448Rock Island County, ILIL141,86934,172–

449Sebastian County, ARAR130,64134,093–

450Mendocino County, CACA88,12234,082–

451Kennebec County, MEME129,06733,896–

452Porter County, ININ176,04933,867–

453Potter County, TXTX114,45333,779–

454Kent County, RIRI173,49533,751–

455Berkshire County, MAMA128,22433,693–

456Kenosha County, WIWI168,44833,663–

457Livingston County, MIMI197,31533,493–

458Outagamie County, WIWI195,89433,488–

459Lower Connecticut River Valley Planning Region, CTCT177,31133,450–

460Scott County, IAIA175,25933,445–

461Apache County, AZAZ64,44533,441–

462Clark County, OHOH135,34033,192–

463Washington County, TNTN141,19932,802–

464Tom Green County, TXTX120,60232,767–

465Yellowstone County, MTMT172,69232,727–

466Monroe County, MIMI156,00432,711–

467Boone County, MOMO191,74632,705–

468Bastrop County, TXTX118,90832,459–

469Blount County, TNTN143,82032,457–

470Cowlitz County, WAWA114,88532,424–

471Houston County, GAGA178,21432,394–

472Calhoun County, ALAL115,83432,381–

473Morgan County, ALAL126,48332,380–

474Cass County, NDND201,79432,351–

475Warren County, KYKY149,37532,347–

476Forsyth County, GAGA282,80532,320–

477Stearns County, MNMN164,11032,188–

478Calhoun County, MIMI133,40832,172–

479Dorchester County, SCSC178,39732,161–

480Livingston Parish, LALA155,03632,066–

481Winnebago County, WIWI174,21832,064–

482Bossier Parish, LALA131,86731,897–

483Rock County, WIWI166,47231,885–

484Randall County, TXTX152,35131,790–

485Flathead County, MTMT115,42931,746–

486Canadian County, OKOK187,18931,732–

487Marathon County, WIWI139,43231,720–

488Josephine County, OROR87,86731,588–

489Blair County, PAPA119,54131,572–

490Portage County, OHOH163,40431,339–

491Grays Harbor County, WAWA78,14431,275–

492Madison County, ININ135,08831,272–

493Flagler County, FLFL140,36031,178–

494Greene County, OHOH174,32231,077–

495Liberty County, TXTX121,36431,010–

496Medina County, OHOH185,02530,942–

497Garland County, ARAR99,69530,934–

498Chittenden County, VTVT169,11530,817–

499Wichita County, TXTX129,55530,695–

500Kenton County, KYKY175,77930,622–

SHOWING 1–500 OF 3,144

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Download CSV (full list, 3,144 rows)

UPDATED 2026-09-11 · DATA: US CENSUS BUREAU ACS 5-YEAR ESTIMATES

Frequently asked

Which county has the highest residents vulnerable to extreme heat?

Los Angeles County, California ranks #1 with 2,956,807 (2022 American Community Survey).

What are the top 5 counties by residents vulnerable to extreme heat?

Los Angeles County, California, Cook County, Illinois, Harris County, Texas, Maricopa County, Arizona, Kings County, New York.

How many counties are in this ranking?

3,144 counties qualify after filtering for population minimums and data availability. The ranking covers 2022 ACS 5-year data.

How is residents vulnerable to extreme heat measured?

Estimated number of people with three or more heat-related social-vulnerability risk factors, from the Census Bureau's experimental Community Resilience Estimates for Heat. The raw-count companion to the heat-vulnerability rate. Source: US Census Bureau, American Community Survey 5-year estimates (2022).