寒波 is read as かんぱ (kampa) and means cold wave.
かんぱ
kampa
だいかんぱ
cold snap
かんそん
poor village
かんれいぜんせん
cold front
よは
waves that remain after the wind has subsided
でんぱ
saying strange things
なみ
ups and downs
よこなみ
beam sea
たんぱ
short wave
たかなみ
high waves
のうは
brain waves
ちょうおんぱ
ultrasonic waves
あらなみ
raging waves