data=ExampleData[{"Statistics","MahanadiRiverFlow"}]

d=d/.FindProcessParameters[data-Mean[data],FARIMAProcess[{},d,{},v]]

eproc=EstimatedProcess[data-Mean[data],FARIMAProcess[4,d,1]]

ListPlot[CorrelationFunction[#,{0,10,1}]&/@{TemporalData@data,eproc},Filling->1->{2},PlotStyle->PointSize[Large],FillingStyle -> Directive[{Thick, Black}],BaseStyle->{FontFamily->"Helvetica"},PlotLegends->Placed[LineLegend[{Style["Data",FontFamily->"Helvetica"],Style["Model",FontFamily->"Helvetica"]},LegendMarkers->Graphics[Disk[]],LegendFunction->"Frame",LegendLayout->"Row"],{Center,Top}],PlotLabel->"Correlation Function",PlotRange->All,ImageSize->400]

fr=TimeSeriesForecast[eproc,data-Mean[data],{10}];
forecast=TemporalData[fr["PathStates"]+Mean[data],fr["TimeList"]];
forecast["Path"]

ListLinePlot[{TemporalData@data,forecast},PlotRange->All,Filling->Axis,ImageSize->400,PlotLegends->Placed[LineLegend[{Style["Data",FontFamily->"Helvetica"],Style["Forecast",FontFamily->"Helvetica"]},LegendFunction->"Frame",LegendLayout->"Column"],{Right,Top}],PlotLabel->Style["Annual Minimum Mean Daily Flows",FontFamily->"Helvetica"]]