Eta Cross-Section of Fgen, Sat EPV, and Omega, at 00z, 09/17

Heavy Rain Band

Feeder Band Zone

Slide Links:

Speaker Notes:

This is an Eta 0-hr cross-section of 2-D frontogenesis (white contours), saturated EPV (with weakly stable (just above zero) and unstable (negative) values shaded), and omega (light blue contours), valid at 00z, 9/17/04. Note the collocation of the main heavy rain bands, north of Ivan's center, with the strongest low-level frontogenesis, low to mid-level instability, and deep-layered lift. Areas near Ivan's convective "feeder bands" to the east and southeast of its center, had a deep layer of instability, but little frontogenesis due to weak temperature gradients.