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Product Description

Storm Relative Mean Velocity is a product derived from base velocity where the average 'storm' motion is taken into account. A radar operator can evaluate an average storm motion for a given scan or series of scans which can in turn can be combined with the velocity evaluated in the base velocity product. This is evaluated on a gate-by-gate basis (a gate essentially being a radial pixel, or single point of data) where the component of the storm velocity that is parallel to the azimuth of the gate is added to the base velocity resulting in either an increase or decrease of velocity evaluated at that point. This is helpful (but not essential) in quickly identifying storm scale rotation in convective weather. Storm rotation is evaluated by identifying adjacent or nearly adjacent gates with significant discrepencies in velocity. That is to say if two adjacent gates show 30kts inbound and 30kts outbound respectively, there is a change in velocity (often noted: Delta-V, DelV or ΔV) of 60kts across these two gates and is indicative of rotation. It is important to remember that the ΔV is what matters. Both in Base Velocity and Storm Relative Velocity, any region of ΔV will be evaluated the same. However, by accounting for storm motion the visual representation of the radar data can make the identification of these areas easier for the human eye to see.

Website Alert Message

Radar Status Message

971 NOUS63 KSGF 181325 FTMSGF Message Date: Jul 18 2024 13:25:25 KVM UPGRADE COMPLETE. JDH

For further information, check the following twitter accounts for periodic updates on product generation status and website improvements; @CoDWXData and @CODMeteorology. Your feedback is always appreciated, so feel free to respond to tweets or send us an email using our Feedback page.

Dual-Pol Radar Site Selection

Change Map Region: CONUS ALASKA HAWAII Addtional Sites: Guam Puerto Rico
Change Map Type: Radar Radar + Warnings

Active Severe Weather Warnings

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Type Counties Affected Tornado Status Hail Size Wind Speed Available Radar(s) Issued by Issuance Time Expire Time

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Missing Data

We were unable to generate this product. This can happen for a number of different reasons. Be sure to check the status of SGF here and/or here. If the site status is normal and this site or product suffers a continuous outage, keep us aware of it by using our Feedback Page.