1. Hard requirements

Physical Windows PC with native DirectX11 GPU (almost impossible to lack on 5-year-old PCs or newer). Virtual machines not currently supported. 

Unfettered internet access with at least 15Mbps download speed. 50Mbps+ recommended for best experience.

 • 15GB free disk space (new requirement in V5.1/V5.2). To minimize CPU and internet bandwidth usage, and to maximize smooth/lightweight experience in WSV3, we now use ample disk space to store temporary uncompressed raster frames (mostly for GOES satellite loops). WSV3 will automatically clear old cache data after time, but the file cache can temporarily balloon to 10GB+ depending on how hard you push the data/loops.     

2. 
Soft requirements/recommendations

• RAM: Depends on how hard you will push loop length/background imagery settings in WSV3. Recommended 4GB free. 32-bit version cannot exceed 2GB. 

• Recommended SSD over Hard Disk. (WSV3 is file I/O heavy) 

• Recommended monitor size no greater than 1920x1080. Set 4K monitors down to HD resolution. WSV3 does not currently support Windows text scaling settings for 4K monitors. Further, the icon objects in WSV3 were not designed for 4K monitors and will appear small. We strongly believe 1920x1080 (or smaller) is the sweet-spot between perceptible visual crispness and resource usage. Higher than this brings tiny visual benefit at huge cost. 

• Better CPU/GPU will improve performance, but there are no hard requirements. WSV3 tends to be more CPU-bound than GPU-bound.

 • Firewalls/anti-virus: As stated on the Download page, anti-virus is not supported. If you must use it, expect it to ruin your ability to use WSV3. However, if you must use a firewall (also not supported), V5.1-onwards should give you much better chances at a normal user experience due to the long-awaited elimination of the old, inferior direct-connect MySQL “optimization server” which required access to Port 3306. All WSV3 traffic should now exclusively occur over HTTP/HTTPS (Ports 80 and 443), however we cannot officially guarantee support with firewalls at this time.                

3. Helpful notes about resource usage

 • The worst/heaviest layers for “lightweight” performance are the background/terrain engine (especially with high tile density settings), the NWS Advisories layer, looping NEXRAD Level 2 data, and making large loops with multiple raster layers, especially the new GOES-R satellite layers. In particular, if you have the GOES-R Extended Imagery subscription, you must be attentive to the huge amount of memory the 1-min Rapid Scan Mesoscale Floater imagery uses and not to exceed the 2GB Win32 memory usage limit. If you push the background tile density on a 1920x1080 monitor and load a ton of 6hr GOES-R/radar data, you can easily hit this limit and cause correct error messages to appear. (V5.2 Update: We've deployed very useful GPU texture compression in this update that will give you more space before you hit this limit, but it still needs to be monitored.)

 • WSV3 is unique because it lets you load up to 6 full hours of past data for smooth, live animated looping to current time. However, you certainly don’t need to set the loop length this long, and we don’t recommend it. Usually the best balance between resource usage and visual result is around a 3 hour loop.

 • Some loopable layers obviously, given their nature, do not support the full 6 hour loop duration (such as the raw MRMS data layer or the NEXRADPro layer).

 • Many layers are extremely lightweight and consume minimal resources. Keeping the map in live state (not looped) consumes minimal resources. Most vector/shape based layers are also very lightweight.

 • Make use of the pre-built performance modes on the header bar to adjust performance. You can also manually adjust the graphics refresh rates in the settings. WSV3 allows for intelligent separation of refresh rate settings depending on the map being in motion or at rest. By default, a non-moving live state display has a lower repaint rate than when it is looping/animating, saving power and bandwidth where desirable.