Paul Manacher of Baltimore says our local forecasters are "usually accurate." But he asks why they "invariably underestimate summer high temperatures." The NWS warning coordination meteorologist for our area, Chris Strong, says his forecasters' predictions last summer averaged a quarter-degree too high for BWI. But they underestimated downtown highs by 3 degrees. Strong says they are not allowing for enough "heat island" effect -- heat absorbed, reflected or re-emitted by buildings and pavement.