WDTs Nationwide Quantitative Precipitation Estimation (NQPE-II) product is derived from the Nationwide Level II mosaics (NMII) every 5 minutes retaining the high resolution 1km grid.

Utilizing ~10,000 guages, WDT provides a Nationwide Gauge corrected QPE (QPEII-GAGE) radar precipitation estimate.

Nationwide Radar QPE tools available:

24 hour Rain Water Accumulation from 21 March,
2006. Total rain water accumulations are in mm.

Rain Water Accumulation (RW)
For each grid when precipitation is identified as rain, the correct classificiation is applied using either the NWS standard stratiform Z-R relationship or the convective Z-R relationship.

Snow Water Equivalent (SWE) Accumulation
WRF model precipitation-typing mask is used to identify areas of snow. When precipitation is identified as snow an instantaneous Z-S relationship is applied (Z=75S2).

24 hour Total Water Equivalent Accumulation
from 21 March 2006. TWE values are in mm

Total Water Equivalent (TWE) Accumulation
Rain Water (RW) accumulation and Snow Water Equivalent (SWE) accumulation are combined to produce a total water accumulation that has been segregated by storm type and delineated by precipitation phase at each grid point, thereby creating a TWE based on combined Z-R and Z-S relationships.

24 hour Snow Depth accumulation from
21 March 2006. SD values are in mm.

Snow Depth (SD)
A series of snow ratio equations are used to convert from snow water equivalent to snow depth based on the temperature at the surface. RUC model analysis data provides the surface temperature information.

National rain gauge locations

NQPE-II with Rain Gauge Bias Removal QPEII-GAGE

Biases can be removed from the radar rainfall estimates using all gauges from WDT's 10000 gauge network.

Each of the NQPE-II tools provides precipitation accumulation at the following intervals:

• 1 hour
• 3 hour
• 6 hour
• 12 hour
• 24 hour