High winds can play havoc with digital-television reception whether you have an outdoor TV antenna or an indoor attic-mounted or set-top antenna. While an outdoor antenna is vulnerable to direct movement by wind, particularly if it is fixed to a tall mast, the problem for indoor antennas is usually multi-path interference caused by nearby trees swaying in the wind. In this situation you will need to re-site the antenna or get rid of the tree to stabilize your digital-television reception.
'Line of Sight' TV Reception
For optimal digital-television reception, antennas need a clear line of sight toward the TV broadcast tower. Any large structure along this line of sight, such as buildings or a nearby tree, can cause signal drop-outs. Buildings don't move enough in the wind to affect the signal strength received by an outdoor or indoor television antenna, but a tree that doesn't usually affect your TV reception may disrupt the signal as it moves and sways in high winds.
A tree located in front of your television antenna can cause a reception problem known as short delay multi-path interference. Signals from the TV broadcast tower overlap chaotically behind the tree and this causes drop-outs on certain TV channels when the wind blows and moves the tree. The problem is usually confined to higher-frequency UHF digital-television channels. In weaker signal areas, multi-path interference can lead to the complete loss of your digital-television signal on UHF channels.
Indoor and Outdoor Antennas
Short delay multi-path interference can affect both indoor and outdoor antennas, but the problem is often worse with an indoor antenna because it typically receives a weaker signal than an exterior antenna. Indoor set-top antennas are usually only recommended for use in strong signal areas close to TV broadcast towers. An attic-mounted antenna will often deliver better results than a portable antenna, but an outdoor antenna is often essential for weak signal areas or reliable long-range digital-television reception.