13. Gulf of Alaska Noreaster

15. If lows and highs aloft and at the surface are above one another, the systems will weaken !

16. Divergence aloft promotes the surface low Convergence aloft promotes the surface high Surface divergence Surface convergence

17. Longwaves

18. MIGRATE THROUGH THE LONGWAVE TROUGHS Chapter 10, page 312 Aguado & Burt

19. 1 2 3 Differential temperature advection intensifies the wave Condensation may release even more heat energy for the storm Less upper level divergence No temp advection