I came across this sentence in a weather report:
Bei schwachem bis mäßigen Südostwind wird es recht warm …
I am aware that bei is followed by the dative case and that adjectives in this situation end in -en. As I assumed schwach was the adjective being used I was therefore expecting schwachen rather than schwachem.
Is schwachem short for einem schwachen? Or is schwachem an adjective in its own right? In which case, why isn’t it schwachemen?