Figures show the eastern half of the US since this is the area of local interest, and topography is not currently included in the calculations (so they may not be as useful over the western US).

The first figure is a four-panel plot of model omega (vertical
velocity in pressure coordinates), total Q vectors and
adiabatic QG omega, along-isentrope Q vectors (Qs)
and QG omega diagnosed from Qs,
and across-isentrope Q vectors (Qn) and
QG omega diagnosed from Qn at 850 mb.
See Keyser *et al.* (1992).

The second figure is the same as the first except for 500 mb.

The third figure shows a four-panel plot of total
ageostrophic wind, the portion of the ageostrophic
wind associated with
the boundary conditions (called the harmonic part),
the rotational portion, and the divergent portion
at 850 mb.
See Loughe *et al.* (1995).

The fourth figure is the same as the third at 300 mb. Note the harmonic potion of the ageostrophic wind at this level can be quite large because the rightmost boundary on the ETA grids we receive is too close to the diagnostic domain.

The fifth figure shows potential temperature, pressure and winds on the dynamic tropopause, taken as the 1.5 PVU surface. Also shown are 1000 mb potential temperature and its horizontal gradient (shaded) and winds, along with the 500 mb model omega.

The software used to generate these diagnostics is freely
available for noncommercial educational and research
purposes.

Keyser, D., B. D. Schmidt, and D. G. Duffy, 1992: Quasigeostrophic
vertical motions diagnosed from along- and cross-isentrope components
of the Q vector.* Mon. Wea. Rev.,* **120,** 731-741.

Loughe, A., C.-C. Lai, and D. Keyser, 1995: A technique for diagnosing
three-dimensional ageostrophic circulations in baroclinic disturbances
on limited-area domains. *Mon. Wea. Rev,* ** 123,** 1476-1504.

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