In MetaStock 6.52 or higher you can easily create the Crude Oil Seasonal Trade #2, as described in the article "Now's The Time to Trade Crude," by John L. Momsen. In MetaStock select System Tester from the Tools menu. Click New and enter the following formulas.

Name: Crude Oil Seasonal Trade #2

Enter Long:
     Month()=8 AND Hgt;=HHV(Ref(H,-1),5)+1

Close Long:
     bc:=Month()=8 AND Hgt;=HHV(Ref(H,-1),5)+1;
     sc:=Llt;=LLV(Ref(L,-1),3)-1;
     trade:=If(bc,1,If(sc,0,PREV));

     sc OR
     If(ValueWhen(1,Cross(trade,.5),H)lt; LLV(Ref(L,-1),8)-1,Llt;= LLV(Ref(L,-1),8)-1,0)
     OR (Month()=9 AND DayOfMonth()gt;=26) OR Month()=10

Click OK and then click Test to run the system.