In Park Personal Training in Harrow

With the recent spate of bad weather, I know that many of you who prefer to do your PT sessions outdoors have been finding it hard to motivate yourselves to workout in the pouring rain and on the sodden muddy ground: which brings me to the point of this post. Is in park personal training and outdoor fitness bootcamps a practical option for those of us who do not enjoy the sunny climes of California or Spain.  What do you guys think?