HYSPLIT Forum: hysplitbbs.arl.noaa.gov

Helo,
im interestingabout this formul P(t+Δt) = P(t)+0,5[V(P, t)+V(P’, t+Δt)]Δt. So my questions is for what stands
V(P, t) –
V(P’, t+Δt)
i cant find. And the answer would be neede ASAP

V(P,t) is the 3-dimensional velocity vector at the initial position at time t

V(P’, t+Δt) is the 3 dimensional velocity vector at the first guess position at time t+Δt

You can read more about this in the technical document at:
http://www.arl.noaa.gov/documents/reports/arl-224.pdf