In my backyard. . .anything that is white and tall. . .attracts big black flies! These insects are smaller than a Horse Fly. . .but larger than a common ordinary House Fly.
Through numerous observations. . .the flies love to “sun themselves on the beach!” meaning that they are attracted to the top of the Tempest because they like something about it (the white color, I guess) and they only land on top when it is sunny! They do not come around the Tempests on cloudy days or days that are cooler than seasonal normal. They fly all around it then the top of the Tempest is covered by a couple of dozen little specks (fly poops!). These are easily removed with a damp paper towel but Tempest must be turned OFF first to prevent bogus rain from being Haptically detected while cleaning the top.
This happens on both of my Tempests. When the Davis Vantage Vue (DVVISS) was the only “white” weather station in the back yard. . .the flies used IT to “sun themselves on the beach.” This year they have left the DVVISS alone and now use both Tempests.
To remedy this. . .I used an old CD disk and traced out a round circle on a clear plastic document protector. Since both Tempests have the Bird Deterrent Accessory spikes on them, I simply pushed the doc protector down onto the spikes then brought it down to the top of Tempest. The clear plastic does NOT affect the UV or the Solar Radiation in any way. . .but when the flies land on it to “sun themselves on the beach”. . .they leave their “calling-cards” on the top of the clear plastic doc protector. . .thus the top of the Tempests remain clean as new!
An experimental test will be to see if the Haptic Rain Sensor can detect rain thru the plastic… instead of having to remove it each time there is rain in the forecast. . .then having to reapply another protector.