WMOD00590

• Title: Analysis and Classification of Mesoscale Cloud and Precipitation Systems
• Date: 8/1/1983
• Weather Modification - Doc Type: Report

longitude and latitude (-22 km) for the detailed mesonet analyses and
AX =Ay = 10 (about 111 km), for the larger area analyses at 0000 GMT.

Vertical moisture flux pqw [(g/m2)/h] is defined as the product
of the density of moist air, p(g/m3), mixing ratio q, (g/kg) and

vertical motion, w, (cm/s). The moist equation of state is commonly

written in the form:

p = p RT (1 + 0.61 q)

(1,2)

where P is the pressure, p the density of moist air, R the gas constant

for dry air, and T the temperature and q the mixing ratio of water

vapor.

Vertical motion in the form of w (ubars/s) may be converted to W
(cm/s) by accounting for de~sity changes with height so that:

w =w AZ p *0.001
AP

(13)

whereAz = thickness between pressure levels (m) andAp is the pressure

change between levels; thus the vertical moisture flux, QW, in units of
(g/m2)/h becomes:

QW = pql.: ~ x 3.6

(14 )

where 3.6 is the units conversion factor.

Vorticity is defined at each pressure surface as: (in units of 10-5/s)

_AV AU_V2_Vl
vx v p - ~x - Ay - 2llx

U2 _ U1
2flY

(15)

47