[Robert Grant]

No amount of signal strength will help you with this problem, but an outdoor antenna will likely help for another reason.

When you use an indoor antenna for DTV, there will always be some degree of multipath reception, as signals are reflected by other houses, buildings, mountains (if you are near any) and trees (in analog reception, mild multipath produces the classic "ghosting" problem. One may recall a windy day when on UHF reception one could not get the picture to stop rolling.)

The very first ATSC (DTV) receivers required a signal that was free of multipath, and could only be used with an indoor antenna if a signal had an unobstructed path to the antenna (e.g, in a window on the side of the building facing a transmitter, with no nearby buildings in the direction of the station).

Newer DTV tuners (including, I believe, all CECBs) can adujst to multipath by assessing the multipath effects on a signal, and "subtracting" the reflections from the total to arrive at a usable bitstream.

The problem with windy weather (and, BTW, it is not the rain, nor the snow, and, with good UHF signals, not lightning) is that when nearby tree branches are windblown, the multipath reflections from trees are changing with time, and the tuner can't "keep up" with the changing multipath condition.

An outdoor antenna aimed at a station has far less multipath to deal with in the first place, and the multipath effects through the tree branches are often not strong enough to corrupt the signal.

Incidentally, not all DTV is UHF. UHF has a much larger share of the total DTV station "stock" than analog, but many stations are and will be on VHF-High band (7-13), with the majority of current analog VHF-High stations going to their true original channels for DTV after June 12th.