California frost dates: B
| City | Last frost | First frost | Season | Zone |
|---|---|---|---|---|
| Badger | Jun 1 | Oct 7 | 128 d | 9b |
| Baker | Feb 14 | Nov 27 | 286 d | 9a |
| Bakersfield | Jan 31 | Dec 8 | 311 d | 9b |
| Baldwin Park | Jan 4 | Jan 2 | 363 d | 10a |
| Ballico | Jan 6 | Dec 20 | 348 d | 9b |
| Bangor | Apr 1 | Nov 17 | 230 d | 9b |
| Banning | Jan 31 | Dec 10 | 313 d | 9b |
| Bard | Jan 8 | Dec 28 | 354 d | 10a |
| Barstow | Feb 22 | Nov 23 | 274 d | 9a |
| Bass Lake | Apr 24 | Nov 4 | 194 d | 8b |
| Bayside | Feb 22 | Dec 7 | 288 d | 9b |
| Beale Afb | Feb 11 | Nov 30 | 292 d | 9b |
| Beaumont | Jan 31 | Dec 10 | 313 d | 9b |
| Beckwourth | Jun 11 | Sep 10 | 91 d | 6b |
| Belden | May 18 | Oct 8 | 143 d | 7b |
| Bell | rare frost | 10b | ||
| Bell Gardens | rare frost | 10b | ||
| Bella Vista | Feb 8 | Dec 28 | 323 d | 9b |
| Bellflower | rare frost | 10b | ||
| Belmont | Jan 17 | Dec 12 | 329 d | 10a |
| Belvedere Tiburon | Jan 4 | Jan 2 | 363 d | 10a |
| Ben Lomond | Mar 25 | Nov 11 | 231 d | 9a |
| Benicia | Jan 17 | Dec 27 | 344 d | 9b |
| Benton | Jun 10 | Sep 17 | 99 d | 6b |
| Berkeley | Jan 3 | Jan 1 | 363 d | 10a |
| Berry Creek | Feb 7 | Dec 18 | 314 d | 9b |
| Bethel Island | Jan 12 | Dec 19 | 341 d | 9b |
| Beverly Hills | rare frost | 10b | ||
| Bieber | May 28 | Sep 29 | 124 d | 7a |
| Big Bar | Apr 16 | Oct 31 | 198 d | 8b |
| Big Bear City | May 27 | Oct 4 | 130 d | 7a |
| Big Bear Lake | May 27 | Oct 4 | 130 d | 7b |
| Big Bend | Jun 3 | Sep 14 | 103 d | 8b |
| Big Creek | Jun 1 | Oct 6 | 127 d | 7b |
| Big Oak Flat | Apr 22 | Nov 2 | 194 d | 9b |
| Big Pine | Apr 29 | Oct 15 | 169 d | 7a |
| Big Sur | Feb 13 | Dec 27 | 317 d | 10b |
| Biggs | Jan 29 | Dec 7 | 312 d | 9b |
| Biola | Feb 18 | Nov 27 | 282 d | 9a |
| Birds Landing | Jan 12 | Dec 19 | 341 d | 9b |
| Bishop | Apr 29 | Oct 15 | 169 d | 7a |
| Blairsden Graeagle | May 21 | Oct 1 | 133 d | 7a |
| Blocksburg | Mar 4 | Nov 22 | 263 d | 9a |
| Bloomington | Jan 10 | Jan 2 | 357 d | 10a |
| Blue Jay | May 5 | Nov 2 | 181 d | 8a |
| Blue Lake | Mar 8 | Nov 30 | 267 d | 9a |
| Blythe | Jan 25 | Dec 12 | 321 d | 9b |
| Bodega | Jan 29 | Dec 30 | 335 d | 9b |
| Bodega Bay | Jan 1 | Dec 31 | 364 d | 10a |
| Bodfish | Apr 5 | Nov 3 | 212 d | 8b |
| Bolinas | Jan 16 | Dec 18 | 336 d | 10a |
| Bonita | rare frost | 10b | ||
| Bonsall | Jan 30 | Jan 7 | 342 d | 10a |
| Boonville | Mar 5 | Nov 21 | 261 d | 9b |
| Boron | Mar 19 | Nov 25 | 251 d | 8b |
| Borrego Springs | Jan 10 | Jan 1 | 356 d | 10a |
| Boulder Creek | Mar 25 | Nov 11 | 231 d | 9b |
| Boulevard | Apr 29 | Nov 1 | 186 d | 9a |
| Boyes Hot Springs | Mar 2 | Nov 27 | 270 d | 9b |
| Bradley | Feb 13 | Feb 1 | 353 d | 9a |
| Brandeis | Jan 24 | Dec 15 | 325 d | 10a |
| Branscomb | Mar 2 | Dec 1 | 274 d | 9a |
| Brawley | Jan 16 | Dec 19 | 337 d | 10a |
| Brea | rare frost | 10a | ||
| Brentwood | Jan 12 | Dec 19 | 341 d | 9b |
| Bridgeport | frost any month | 6a | ||
| Bridgeville | Mar 4 | Nov 22 | 263 d | 9a |
| Brisbane | Dec 29 | Dec 26 | 362 d | 10a |
| Brookdale | Mar 25 | Nov 11 | 231 d | 9b |
| Brooks | Apr 7 | Dec 5 | 242 d | 9a |
| Browns Valley | Apr 1 | Nov 17 | 230 d | 9b |
| Brownsville | Apr 1 | Nov 17 | 230 d | 9a |
| Bryn Mawr | Jan 27 | Dec 19 | 326 d | 10a |
| Buellton | Apr 11 | Nov 8 | 211 d | 10a |
| Buena Park | rare frost | 10a | ||
| Burbank | Jan 2 | Dec 26 | 358 d | 10a |
| Burlingame | Dec 29 | Dec 26 | 362 d | 10a |
| Burney | Jun 3 | Sep 14 | 103 d | 7b |
| Burnt Ranch | Apr 16 | Oct 31 | 198 d | 8b |
| Burrel | Jan 30 | Dec 11 | 315 d | 9a |
| Burson | Jan 22 | Dec 17 | 329 d | 9b |
| Butte City | Mar 4 | Nov 17 | 258 d | 9b |
| Buttonwillow | Feb 9 | Nov 26 | 290 d | 9a |
| Byron | Jan 19 | Dec 10 | 325 d | 9b |