The Promised Land is not like Egypt. In the Promised Land, there's rain. That's a huge deal, since the Egyptians depended on the Nile for water. And water meant life.
Of course, the writers link weather patterns with God. If the people disobey, God will withhold rain from them.
Looking for a recap of 6:6-9? You've come to the right place. Yeah, we know. Deuteronomy is a bit redundant, but it definitely helps us remember the stuff.
If the people obey the "entire commandment," God will drive out the other nations. Moses even gives us pretty specific parameters of the land they'll have (22-25).
Deuteronomy believes in The Doctrine of the Two Ways, and it's pretty clearly stated here: Those who obey God are blessed and those who don't are cursed. These verses foreshadow 27:11 where half of the tribes stand on Mt. Gerizim to pronounce blessings, and half stand on Mt. Ebal to pronounce curses (26-31).
Interested in learning more about The Doctrine of the Two Ways? Wander on over to "Theological Point of View." Just don't get lost in the wilderness for 40 years.