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This slide shows a cross-section of saturated equivalent potential temperature, geostrophic momentum and relative humidity, valid at 00 UTC on the 9th. Note that the orientation of the cross-section has shifted slightly from the cross-sections shown earlier, in order to be more perpendicular to the thickness lines. As a result, the "feeder band" is no longer depicted in the cross-section.

Mid-level gravitational instability is indicated above the heavy rain band just above 700 mb by this 6-hour Eta forecast cross-section of equivalent potential temperature (equivalent potential temperature decreases with height). Slantwise instability is indicated just below 700 mb (equivalent potential lines are slightly steeper than the geostrophic momentum lines in a region near saturation).