Well, you would have to arbitrarily pick a "cut-off" time for the precip data (like Dec 31 or something) and then determine the precips effects on the species (which will vary depending on the ecology of the species being predicted). Then, you would have to arbitrarily pick a lag time in which the species will then realize the supposed effects of this precip. For example, "a high precip year may not impact seral shrub growth until the following spring" or something of this nature. Now, if your talking about direct impacts on survival such as quail, you could assume an immediate impact on the population such as a very wet spring causing increased chick mortality or something of this nature.

Again, though it's basically armchair population dynamics with no real trendpredictor value.