This should be considerably less likely now (still possible, but less likely to occur on a regular basis).
Jon and I put together a system of rules for determining the thresholds at which these indicators are displayed, which we'll be applying on a regular basis (to this and other sites). The critical issue for the LQ queue is that it generally takes 2-3 reviewers per task to dequeue - that's likely to cause tasks to stay in the queue long enough to light up the indicator twice (it cannot light up more than once per hour for each individual). So ideally, we set the threshold just high enough that it usually takes more than an hour to build up the required number of tasks - this then gives more reviewers time to process them when it appears, as some portion of them will be completed each time the indicator draws more reviewers in.