# Presentation: 520537

## The Use of the Multi-sensor Precipitation Estimator Software at the West Gulf RFC

- Greg Story
- HAS Forecaster
- West Gulf River Forecast Center
-  Fort Worth
- 2004 NWA Annual Meeting

## In Texas, we need accurate rainfall estimates

**I-20 bridge near Pecos, TX April, 2004**

## What is the Multi-sensor Precipitation Estimator?

**● ****Software used to generate rainfall estimates for the WGRFC hydrologic model**
**● ****Makes an estimate of precipitation using rain gauge data,  output from WSR-88D, and satellite precipitation estimates**
**Since radar precipitation estimates are frequently in error, MPE applies biases (both field and local bias) to the hourly radar product**

## What is MPE? (continued)

**Creates a multi-radar mosaic**
**Uses radar with the lowest beam elevation in overlapping areas**
**Uses radar climatology to define ****“effective radar coverage”**
**Merges radar mosaic with gauge observations**
**Allows user to draw in precipitation values (i.e. light snow) **
**Allows user to “fill in” areas of no radar estimates or rain gauges with  Satellite Precipitation Estimates (SPE)**

## Improving RainfallEstimates

**Using polygon edits, several fields are available to be inserted into MPE**
**Satellite Precipitation Estimates (SPE)**
**Gauge only field**
**Local bias radar field**
**Mean Field Bias radar field**
**These fields can be used to remove A/P, or as an insert where one rainfall field may be more appropriate than any other. It becomes a “jig saw puzzle” when finished.**

## Incorporating Satellite Estimates

**Multi-sensor Mosiac**

**Multi-sensor Mosiac and Satellite Estimates**

## The Whole Point

**	****The main objective of MPE is to reduce both areal-mean and local bias errors in radar-derived rainfall using rain gauges and satellite so the final multi-sensor rainfall product is *****better than any single sensor*****.**

## Big Bend Region - 07/28/04

- Raw Radar Field

## Big Bend Region - 07/28/04

- Gauge Only Field

## Big Bend Region - 07/28/04

- Satellite Derived Precipitation

## Big Bend Region - 07/28/04

- Best Estimate QPE (Multi-sensor Field)

## Dallas, TX - 7/29/04

- Raw Radar Field
- No bias applied – you will note the underestimation of the rainfall south of Dallas

## Dallas, TX - 7/29/04

- Gauge Only Field

## Dallas, TX - 7/29/04

- Mean Bias Field
- One bias value applied to the entire radar umbrella

## Dallas, TX - 7/29/04

- Local Bias Field
- Local bias applied to radar estimates, but is biased to the rain gauges and not to the entire radar umbrella

## Dallas, TX - 7/29/04

- Mean Bias

- Local Bias

- Best Estimate

## Dallas, TX - 7/29/04

- Best Estimate QPE
- Saved Multi-sensor Field (combined local bias radar, field bias radar, and gauge-only fields)

## Dallas, TX - 7/29/04

- 24 Hour Total Rainfall
- Estimate
- Ending 12z 7/29/04
- MPE estimate was
- 13.74” near Mansfield, Texas
- Rain gauges confirmed 13.65”

## MPE is now run at NWS WFO’s

**Once only at RFC’s, MPE is now available at WFO’s**
**MPE serves as input to the WFO’s Site Specific Hydrologic model**
**Radar Field bias sent to ORPG to be applied to precip products**
**Allows monitoring of radar rainfall estimates from multiple radars**

## MPE National Operations Team

**Review WFO MPE Operational Concept **
**Identify MPE information at RFC’s which can assist the WFO’s in using MPE more efficiently**
**Rain gauge data**
**Field bias information**
**MPE Climatology information**

## Questions or Comments?

**Precipitation products are available through our web site:**
**http://www.srh.noaa.gov/wgrfc **
**West Gulf RFC – HAS Team**
**(817) 831-3289 x 4**
**Greg Story****	****x 204**
**	****E-Mail:  **_**[Greg.Story@noaa.gov](mailto:Greg.Story@noaa.gov)**_