Weather-Ready Nation; Cooperative Observers; Daily Briefing; Damage/Fatality/Injury Statistics; Forecast Models; GIS Data Portal; NOAA Weather Radio; Publications; SKYWARN Storm Spotters; StormReady; TsunamiReady; EDUCATION . Be A Force of Nature; NWS Education Home; NEWS . NWS News; Events; Social Media; Pubs/Brochures/Booklets ; NWS Media Contacts; SEARCH
The gradient is a fancy word for derivative, or the rate of change of a function. Itâs a vector (a direction to move) that. 1  Points in the direction of greatest increase of a function (intuition on why)  Is zero at a local maximum or local minimum (because there is no single direction of increase)
For a function of two variables z=f(x,y), the gradient is the two-dimensional vector <f_x(x,y),f_y(x,y)>. This definition generalizes in a natural way to functions of more than three variables. For the function z=f(x,y)=4x^2+y^2.