At least it has in the northeast. 4 straight days of 75+ sunny weather predicted to last through the weekend (even as not all that far in the midwest they are getting 6+ inches of snow.)
Usually around this time of year the Mountain Hardware Elkommando kilt, which I think is one of the best for warm weather hiking, goes on sale at many of the online retailers. It started yesterday at Mountain Gear selling for $60 (regularly price is $75). REI, Altrec and others usually follow with similar sales.
This fall and spring, when temperatures remained above 30, I used a Stillwater wool kilt (on the coldest days) and a Stillwater acrylic (the Thrifty Kilt) on less cold days. Both worked well in their respective temperature ranges, but the thrifty kilt seem a bit warm on last weekend's hike where the temps were in the mid 60's.