Under the influence of a one-dimensional stationary outfield with the equilibrium between kinetic andpotential energy produced by it,a modified Sch(?)rdinger equation in the form i((?)ψ/(?)t)t=a (?)~2ψ/ax~2-ib(?),where b=b(?)T/(?)x,is used to describe the behavior of the probability wave on the six-monthdeparture charts at the 500 hPa level.It is found that C=2πa/L-b(?)T/ax and when L→∞,then C=-b(?)T/(?)x,where C is wave velocity,a and b are constants,and L is wavelength.The motion direction ofprobability waves is against the outfield temperature gradient,and their velocity is related to the absolute valueof temperature gradient.The motion of waves shrinks in heat sinks and expands in heat sources,which have beenverified in practice.Finally the six-month departure probability wave and the modified Sch(?)rdinger equationare used in the MOS predictions of temperature and rainfall in spring-summer 1981-1985 in Jilin Province andthe accuracy for trend predictions is equal to 80%.