Update: See below for BC map of stations (Blue are the cold ones …) 

The stations are the ones with “Departure from 1971-2000 Normals” data (the D column) from here:

http://climate.weatheroffice.gc.ca/prods_servs/cdn_climate_summary_report_e.html?intMonth=5&intYear=2012&prov=BC&txtFormat=text&btnSubmit=Submit
Environment Canada
Monthly Values for May 2012
Stn_Name                | Lat   | Long    |Prov | Tm  |DwTm| D  | Tx  |DwTx| Tn  |DwTn| S   | DwS|S%N|  P  | DwP|P%N|S_G|Pd |BS |DwBS|BS%| HDD  | CDD  |Stn_No

CHEMAINUS               |48.935 |-123.742 |BC   | 12.7|   0|     | 24.0|   0|  3.5|   0|  0.0|   0|   | 40.4|   0|   |  0|  5|   |    |   | 166.1|   0.5|1011500
LAKE COWICHAN           |48.829 |-124.052 |BC   | 10.4|  15| -1.5| 29.5|  11|  0.0|  10|  0.0|  11|   | 50.2|  11|   |  0| 10|   |    |   | 121.9|   0.0|1012055
DISCOVERY ISLAND        |48.424 |-123.225 |BC   | 11.0|   0|     | 21.1|   0|  5.9|   0|     |    |   |     |    |   |   |   |   |    |   | 216.9|   0.0|1012475