NASA Wallops Flight Facility — Precipitation Events
Precipitation Research Facility
77 instruments · 5831 events
2026-01 to 2026-10
built 2026-10-31 06:21 UTC
2026-01 to 2026-10
built 2026-10-31 06:21 UTC
What each instrument on this page is, and what it measures.
OTT Parsivel2 — laser optical disdrometer. A particle crossing the sheet dims the beam: the depth of the dip gives an equivalent diameter, the length of it gives a fall speed. Reported as a 32 × 32 diameter-by-velocity count matrix each minute, which is where the drop-size, fall-speed and phase panels come from.
Metek MRR-Pro and Metek MRR-2 — vertically pointing 24 GHz FM-CW Doppler radars. They profile reflectivity and fall speed above the site rather than measuring at the ground.
MetOne 380 — 0.01 inch (0.254 mm) per tip. Depth comes from counting tips, so a gauge only registers once enough water has collected: it resolves totals well and onset poorly, which is why the all-in-ones borrow their rain periods from a disdrometer where one is available.
Lambrecht meteo heated buckets — 0.2 mm per tip, fitted as bucket A on PIERS0027 and PIERS0028. Being heated, they measure frozen precipitation that an unheated gauge would simply collect and hold. Their different tip volume is applied per bucket, so the A and B gauges on those platforms are scaled independently.
RM Young ResponseONE — temperature, humidity, pressure, wind speed and direction, and no precipitation sensor.
Lufft WS800 — the same, plus an aspirated radiation shield, radar precipitation measurement, a pyranometer and lightning detection. It measures its own precipitation, so unlike the other all-in-ones it does not borrow rain periods.
10 m — a Vaisala HMP155 temperature and humidity probe with an RM Young 05103 mechanical anemometer. Temperature, humidity, wind speed and wind direction are measured here.
3 m — the same HMP155 and 05103, plus a Vaisala WXT520 all-in-one, which is what supplies pressure and dew point for the tower.