It seems that this has changed recently, though: Anthony now has an update in his second discussion second thread where he
notes that «With the advent of the successor display to the MMTS unit, the LCD display based
Nimbus, which has memory for up to 35 days (see spec sheet here http://www.srh.noaa.gov/srh/dad/coop/
nimbus-spec.pdf) they stopped worrying about daily readings and simply filled them in at the end of the month by stepping through the display.»