• HAST 13:37
  • AKDT 15:37
  • PDT 16:37
  • MDT 17:37
  • CDT 18:37
  • EDT 19:37
  • UTC 23:37



"I love the HEMS Tool product! It's great, fantastic, and I've been using it since its inception. I find the HEMS Tool intuitive, informative, easily readable, and applicable in almost any weather. ... I wish we had it associated with my NEXRAD in the aircraft!"
- Sam J, OH EMS Pilot
"This is great! Thanks for adding a tool that can be used by the helicopter community for weather planning."
- Steve T, US Army Pilot
"It is a great resource, and is always my first stop for a comprehensive weather snapshot for go/no go mission decisions."
- Jeff B, CA EMS Pilot

The Helicopter Emergency Medical Services (HEMS) Tool has been specially designed to meet the needs of low-altitude VFR emergency first responders. It runs as a desktop application on your computer for maximum performance.

The HEMS Tool can overlay multiple fields of interest: ceiling, visibility, flight category, winds, relative humidity, temperature, radar (base and composite reflectivity), AIRMETs and SIGMETs, METARs, TAFs, and PIREPs.

All 3D data are interpolated to AGL altitudes and can be sliced horizontally on 500 ft intervals up to 5000 ft. All data can be animated in time.

The tool has high-resolution basemaps, including colored elevation, shaded relief, and elevation contours, streets, hospitals, airports, and heliports for the entire United States. More detail is revealed as you zoom in and individual layers can be turned on or off independently. The tool can also overlay custom map data from a user's local or remote shapefile.

Preferred views can be saved for quick recall later and automatically update with current data. Views include the selected weather grid, overlays, map layers, and zoom. They may be saved locally to the user's computer or remotely on the Experimental ADDS servers for use from other computers in future sessions.

Basic functions and new features of the HEMS tool are illustrated in the two demonstration videos below.


  • AGL interpolated data for low altitude flight
  • Time animation of evolving weather
  • High-resolution basemaps
  • Saving of preferred views

Requirements strut.rap.ucar.edu strut adds-web2