An improvement to the WSR-88D radar scanning strategy is called MESO-SAILS, Multiple Elevation Scan Option-SAILS. It enables the radar to provide up to four low-level views of the storm within a five minute period. This is done by coming back down regularly to the lowest scanned elevation during the course of a full vertical scans of many angles.
Because of this, the forecaster can see the lowest and most important portion of the storm as quickly as every 75 seconds. That means better and faster detection of hazardous weather, ultimately leading to more advanced warnings.
US national Weather Service of NOAA
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