How to set a range in an "if" statement?

I am trying to set up a function in a way that it will only proceed if two conditions are met: if the variable is greater than another and smaller than a third one. This is what I have:

########################################################################
def Read_Data(file_location, start_date, end_date):
########################################################################
    #imports file
    fname = (file_location)
    ncfile = netcdf_file(fname,'r');
    #reads file and prepares it for usage
    juld = np.array(ncfile.variables['JULD'][:])
    juld[juld<start_date]=float('nan')
    juld[juld>end_date]=float('nan')
    if start_date<juld<end_date:
        temp = np.array(ncfile.variables['TEMP'][:])
        temp[temp>45]=float('nan') #eliminates inaccurate data
        temp[temp<-10]=float('nan') #eliminates inaccurate data
        lon = np.array(ncfile.variables['LONGITUDE'][:])
        lat = np.array(ncfile.variables['LATITUDE'][:])
        ncfile.close()
        return temp, lon, lat, juld

I have two functions over this one that define start_time and end_time, as well as a loop that processes the files. As you can see by my "if" statement, I am trying to set a range of numbers, and if the file's data fits the range, the reading will proceed. When I set it as I did, however, I get this error:

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

I don't understand how to solve this, especially because I am using two variables (start_date, end_date: both are given a numeric value on the previous function). In short, how to I make my desired "if" statement possible.

Edit

In addition, I want the files that don't meet the criteria to be ignored, and I am not sure if they will be if I don't write an "else" statement.