# Presentation: 295487

## Mesocyclone Rapid Update

**Mesocyclone Rapid Update**
**Requirements**
**ORPG Build 4 – AWIPS OB2**
**Mike Istok**
**NWS/OS&T/SEC**
**NPI Development Manager**
**30 December 2002 (Final)**

## ORPG Build 4 WSR-88D MRU Product Functional Requirements 

**The Mesocyclone Rapid Update (MRU) product is generated once per elevation scan**
**Mesocyclone Algorithm information from an elevation scan is based on elevations that have been completed thus far in the current volume scan**
**This information is combined with the previous volume scan Mesocyclone and Storm Track Algorithm information**
**Average motion of all SCIT cells from the previous volume is used to derive forecast positions of previous features at the current volume scan time**
**In feature type order, the forecast position of each previous feature is matched to the closest current feature within a search radius defined by SCIT algorithm**
- Current unmatched 3D features are New
- If previous volume is unavailable, all features are New

## ORPG Build 4 WSR-88D MRU Product Functional Requirements(cont.)

**Current features inherit attributes (associated storm ID, feature type, maximum tangential shear and the diameters and height of this shear, top height, base azimuth, base range, base height) of the matched previous feature**
- Position attributes (base azimuth, range, and height) of _matched_ previous features are updated to the “_current_” detection
- Top height is updated if the top of the current detection is taller
- Position attributes (base azimuth and range only) of _unmatched_ previous features are _extrapolated_  to the forecast position
- Strength attributes (feature type, maximum tangential shear) are updated to the “_current_” value, if _increasing_ in magnitude.
- The radial/azimuthal diameters and height of the maximum shear are also updated if the max tangential shear increases
**Feature status categories are persistent, increasing, new, and extrapolated**
**At the end of the volume scan extrapolated features are removed**

## ORPG Build 4 WSR-88D MRU Product Functional Requirements(concluded)

**Product is used to generate a graphic display, graphic overlay to other products, and alphanumeric displays**
**Product includes annotations for the product name, date and time of volume scan, and elevation angle**
**Product format requirements**
- Graphic 3D feature symbols
- 3D features that are new, persistent, increasing, or extrapolated
- Packet #20 to report _current_ (new, persistent, & increasing) and _extrapolated_ mesocyclone and 3-D correlated shears features
- Identify storm ID associated with each mesocyclone
- Graphic alphanumeric table
- 3D features that are new, persistent, increasing, or extrapolated
- Display character ^ (8-bit hexadecimal 5E) next to  _current_ data
- Tabular alphanumeric table
- 3D features that are new, persistent, increasing, or extrapolated
- Increasing, persistent, and extrapolated 2D features
- Display character ^ (8-bit hexadecimal 5E) next to  _current_ data

## MRU Product Template

## MRU Product Format Examples

## MRU Overview and Terminology

## AWIPS OB2 Functional Requirements

**Mesocyclone Rapid Update (ORPG Build 4 generates new elevation based product, based on user request)**
- User requests the MRU product three different ways
- All elevations, lowest x elevations, specific elevation angles
- Can archive and read-back all MRU products
- Display as overlay to other products from same volume scan
- User option to choose between displaying the latest elevation (i.e., highest elevation) and displaying a specific elevation
- When the latest elevation is selected, the display will automatically update when higher elevation products are received
- Highest elevation MRU is used as overlay in time loops
- Negative condition (no features) must be displayed
- Annotate displays with elevation angle of the MRU product

## AWIPS OB2 Functional Requirements

**Mesocyclone Rapid Update D2D display requirements**
- Graphic display of 3D feature icons
- Display traditional AWIPS mesocyclone and 3-D correlated shear symbols for _current_ and use dashed symbols for _extrapolated_ features
- Toggle to turn off display of extrapolated features
- Graphic alphanumeric table (grid/text D2D display)
- Display like other graphic alphanumeric products
- Tabular alphanumeric table  (AWIPS text viewer)
- Display like other tabular alphanumeric products