____________________ air masses seldom hit the United States, but ...

[bobthebuilder]

___________________ _ air masses seldom hit the United States, but can break low-temperature records when they do.
 Fill in the blank(s) with correct word

Question 2

____________________ ___________________ _ air masses often form over northern mainland Canada.
 Fill in the blank(s) with correct word

[ynlevi]

Answer to Question 1

Arctic

Answer to Question 2

Continental polar