Even though London would still have been a bit thin of company in January, not to mention cold, one assumes that at least some members of fashionable Society maintained the practice of promenading through Hyde Park in the late afternoon. The addition of a fur muff (my favorite Regency accessory!) to this ensemble at least helped keep the lady warm on her walk.
The print is described in the magazine as follows:
“A plain cambric robe, with long gathered sleeve and high arched collar, trimmed with net lace or muslin. A Spanish lappelled coat of fine orange Merino cloth; full epaulette ornaments on the shoulders: the whole line throughout with white sarsnet, and trimmed with a raised border of white velvet or swansdown. A small provincial bonnet of the same material as the coat, ornamented with a full curled ostrich feather. White spotted ermine or Chinchilli muff. Gloves grey or light blue kid. Half-boots of orange-coloured jean or velvet.”
Similar outer garments in other prints are almost always called a pelisse. It is interesting that in this case, it is called a coat.