In the Bob Tait Meteorology book, practice exam 1 at the back, question 16-

refer to meteorological message on page 8.16
The forecast visibility for area 22 is:

Given that under the visibility section of the ARFOR, it states : 4000m SH/DZ/TS
I had chosen the answer : 4000 metres with SH/DZ/TS

The correct answer being 10Km reducing to 4000m in SH/DZ/TS

Given that the ARFOR has an attatched TAF for YMIA which states visibility at the aerodrome is 10Km or greater, I can see where I went wrong, however I've noticed that in the booklet provided in the exam, the ARFORS are exactly the same as those provided in the Bob Tait book, except for the TAF's have been removed. So in the exam, where this TAF does not exist, the most correct answer would be what I originally chose, correct?
As one could not be sure that the visibility is any better than 4000m anywhere within Area 22.
Or would the answer remain the same, with the ARFOR simply stating visibility is 4000m within SH/DZ/TS

Thanks in advance, fingers crossed for Met exam on Tuesday

If an area forecast says the visibility is 4000m SH/DZ/TS it means just that. The visibility will be 4000m if you are in the drizzle or thunderstorms [hope you are not!].

The visibility in the rest of the area will be unrestricted at 10km or better. When you think of it, it would be a pretty unusual day if the visibility over the entire met area was 4000m.

Makes perfect sense, cheers.