Rudy noticed that these sensors were down.  After resetting power on both:

200m: TRH30 9.49 65.31 8 0 1238 129 26\r\n

(fan has low current)

300m: TRH16 -40.14 0.00 9 0 0 0 30\r\n

(sensor is essentially dead)

Both sensors are going through frequent reset cycles as well.  I don't know if we even have replacement sensors ready to go.  (Or whether we should bother with fixing this with one week left in the project, officially.)

(It probably is obvious, but there have been a lot of thunderstorms today that may have helped these sensors die.  Both sonics at each level are still chugging away, though they all are reporting a 0x0f in the status, which may indicate wet transducers?)