If you have a fleece cooler, you could layer that under the LW to make it a bit warmer... I don't know how well that would work but it might be worth a try...
Personally, for the conditions we get here (if it's 45* or below, there's a cold wind, lots of rain, etc etc) I prefer to over-blanket Lacey. Granted, she is older and her internal sense of temperature seems to be rather messed up (she overheats like nobodies business in the summer and gets chilled very easily in the winter). For her, 45* is perfect MW weather (unclipped - if she were clipped like she was last year, 50* with a cool wind is MW) and 35* is HW weather.
Fabio - 13 year old Arabian/Lipizzan gelding
Hazel - 14 year old Angora goat
Atticus - 4 year old LaMancha/Alpine cross goat
Rest peacefully, Lacey.