SASENOAA Interface Engine
SAS Output Data Set
You can use a SAS DATA step to write the selected NOAA Severe Weather Data Inventory data to a SAS data set. This enables you to use SAS software to easily perform data analysis. If you specify the name of the output data set in the DATA statement, the SAS engine supervisor creates a SAS data set that has the specified name in either the SAS Work library or, if specified, the SAS User library.
The contents of the SAS data sets are described in the section Examples: SASENOAA Interface Engine and summarized in Table 3 through Table 7. Each type of SWDI data set contains its own columns and variables, and the resulting SAS data set is named by the OUTXML= option specification. When the ID= option is used, another SAS data set is created with _M appended to the original data set name, and if the STAT= option is used, then another data set is created with _S appended to the original data set name.
You can use the PRINT and CONTENTS procedures to print your output data set and its contents. Alternatively, you can view your SAS output observations by opening the desired output data set in a SAS Explorer window. You can also use the SQL procedure with your SASENOAA engine libref to create a custom view of your data.
Table 3: NX3HAIL NEXRAD Level III Hail Data Set
| Variable Name | Description |
|---|---|
| wsr_id | NEXRAD or Terminal Doppler Weather Radar (TDWR) site ID |
| cell_id | Cell ID unique to radar site |
| prob | Probability of hail (percentage) |
| sevprob | Probability of severe hail (percentage) |
| maxsize | Maximum size of hail (in) |
Table 4: NX3MESO NEXRAD Level III Legacy Mesocyclone Data Set
| Variable Name | Description |
|---|---|
| wsr_id | NEXRAD or Terminal Doppler Weather Radar (TDWR) site ID |
| cell_id | Cell ID unique to radar site |
| cell_type | 'Meso', '3dc shr', or 'unc shr' |
| range | Range (naut. miles) |
| azimuth | Azimuth (deg) |
| base_height | Base height of feature (kft) |
| height | Height of feature (kft) |
| radial_diam | Diameter of feature along range axis (naut. mi) |
| az_diam | Diameter of feature in azimuth angle (deg) |
| shear | Wind shear (E-3/s) |
Table 5: NX3STRUCTURE NEXRAD Level III Storm Structure Data Set
| Variable Name | Description |
|---|---|
| wsr_id | NEXRAD or Terminal Doppler Weather Radar (TDWR) site ID |
| cell_id | Cell ID unique to radar site |
| range | Range (naut. mi) |
| azimuth | Azimuth (deg) |
| vil | Vertically integrated liquid (kg/ ) |
| max_reflect | Maximum reflectivity (dbz) |
Table 6: NX3TVS NEXRAD Level III Tornado Vortex Signature Data Set
| Variable Name | Description |
|---|---|
| wsr_id | NEXRAD or Terminal Doppler Weather Radar (TDWR) site ID |
| cell_id | Cell ID unique to radar site |
| range | Range (naut. mi) |
| azimuth | Azimuth (deg) |
| max_shear | Maximum shear (E-3/s) |
| mxdv | Maximum delta-velocity (knots) |
Table 7: NX3MDA NEXRAD Level III Digital Mesocyclone Detection Algorithm Data Set
| Variable Name | Description |
|---|---|
| wsr_id | NEXRAD or Terminal Doppler Weather Radar (TDWR) site ID |
| cell_id | Cell ID unique to radar site |
| str_rank | Strength ranking |
| scit_id | ID in storm cell identification and tracking (SCIT) algorithm |
| range | Range (naut. mi) |
| azimuth | Azimuth (deg) |
| ll_rot_vel | Low-level rotational velocity (kt) |
| ll_dv | Low-level delta-velocity (kt) |
| ll_base | Base (kft) |
| depth_kft | Depth (kft) |
| dpth_stmrl | Storm-relative depth (percentage) |
| max_rv_kft | Maximum rotational velocity height (kft) |
| max_rv_kts | Maximum rotational velocity (knots) |
| tvs | Tornado vortex signature (yes or no) |
| motion_deg | Motion direction (deg) |
| motion_kts | Motion speed (kts) |
| msi | Mesocyclone strength index |
The storm cell identification and tracking (SCIT) algorithm is an enhanced WSR-88D algorithm that is outside the scope of this chapter, but this section briefly summarizes some of the variables in the NX3MDA data set. Storm-relative depth is the ratio (expressed in percentage) of meso-depth divided by the storm depth as determined by the SCIT algorithm’s cell. Strength ranking and mesocyclone strength index (MSI) are nondimensional numbers that provide a way to determine the 3D-integrated intensity value of the detection.
Max_rv_kft is the height (in kilofeet) at which maximum rotational velocity was detected; it might or might not be associated with the lowest radar elevation angle. Max_rv_kts is the rotational velocity in knots; it might or might not be associated with the lowest radar elevation angle. The variables ll_rot_vel, ll_dv, and ll_base are always associated with the lowest elevation angle, so max_ and ll_ values are sometimes identical.