The most common and most likely answer to this crossword clue is the 7 plus 7 letter word WEATHER STATION
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More clues leading to the result WEATHER STATION
- Met employees here having come through Waterloo?
- Observation post observing conditions on area with test ground
- It’s another wet start to afternoon, possibly? Get that info from here
- If told, saint to go round where Meteorologists work
- Male sheep reportedly with a base at a meteorological observation post
Buddy explains!

The straight part
We know that "meteorological observation post" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case meteorological observation post = weather station.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.