Meteorologists often use the term precipitation when predicting weather conditions in the future.
From the Edmonton Journal:
But get ready to don your warm, waterproof gear come September,
October and November when southern and central Alberta may see
significantly more precipitation than usual.
“In November, it’s most likely not going to be rain,” Kulak said [a warning preparedness meteorologist for Environment Canada.]
In November it might not rain in Edmonton, but the weather expert cannot know for certain; he is merely speculating. If it became cold enough there could be sleet; or hail; or even snow.
On the UK Met Office site I found this definition of precipitation:
What is precipitation?
The definition of precipitation is any form of water - liquid or solid
- falling from the sky. It includes rain, sleet, snow, hail and drizzle plus a few less common occurrences such as ice pellets,
diamond dust and freezing rain.
Thus the word precipitation is best left to the meteorologists when they are making short or long term weather forecasts.
In the OP's case, the expression precipitation has been used incorrectly.
"there is probably precipitation right now"
If the OP insisted on using the term then she ought to say
It was precipitating when I arrived at work. This however, sounds stilted and is too vague to be of any real help. The person asking for information is left none the wiser. A far more natural, and more accurate description, as suggested by @John M. Landsberg in the comment section, would be to say
It was raining/snowing/hailing when I arrived ten minutes ago
thereby leaving the asker; the task and responsibility of checking the weather conditions for him or herself.