Weather Links

Here are some web resources that we use most frequently while we storm chase. We typically look over all model data in the days leading up to a severe weather event, and then re-evaluate the models on the morning of a chase. Once storms fire, we continuously monitor Realtime Data, the SPC, and the HRRR.

National Weather Service


Realtime Data


  • Radarscope – Low-cost super-resolution radar solution for Mac, iPhone, and Android. This is a must-have for any chaser.
  • GR2Analyst – I strongly recommend this product for serious chasers. When configured properly, GR2AE provides the most timely radar updates, and is the most versatile analysis tool. We strictly prefer Level-2 super-resolution data. Requires Windows XP or higher.
  • GRLevel3 – Low-resolution Level-3 data (however velocity data is close to super-resolution). We use it most frequently for its VWP plots. Requires Windows XP or higher.
  • SHARPpy – Useful for displaying observed and modeled sounding data. Works on Mac, Linux, and PC.
  • GpsGate – Allows an external GPS to be shared across multiple programs in Windows.
  • DeLorme Street Atlas – Don’t rely on Google for maps. You can track your location with this application, and will always have maps. We also recommend paper maps!
  • Spotter Network – Report the severe weather that you observe!

Numerical Weather Prediction Models:

  • Very short-range
    • HRRR Operational (ESRL) – 2.5km Resolution, 15hr forecast, updates hourly.
    • HRRRX Experimental (ESRL) – 3km Resolution, 24hr forecast, updates hourly but is sometimes delayed.
    • NSSL WRF – 4km Resolution, 24hr forecast, initialized twice per day at 00z and 12z. Usually available around 07z.
    • 4km WRF – 4km Resolution, 36hr forecast, initialized twice per day, at 00z and 12z.
    • RAP (ESRL) – 13km Resolution, 27hr forecast, updates hourly.
    • SSEO – SPC’s ensemble some of the above models. 24-36hr forecast, updates 1-2 times per day.
    • NCAR Ensemble -48-hour 10-member ensemble of high-resolution models. 48 hour forecast, updates once per day (00z), around 3am CDT.
  • Short-range
    • SREF – Ensemble of 21 medium-range, medium resolution models, and the operational NAM. 87hr forecast, updates 4 times a day.
    • 4km NAM – 60hr forecast, updates 4 times a day.
  • Non-government model graphic websites: these are run by individuals, organizations, and educational institutions. You can find some of the above models as well as medium and long range models here.
    • College of DuPage – SHARPpy soundings, ultra long-range CFS maps… get that hypetrain chugging early.
    • Tropical Tidbits – Lots of international models. NAM 4, 12, and 36km maps. Worldwide regions.
    • Pivotal Weather – Point and click SHARPpy soundings, and a unique variety of numerical models.
    • Twisterdata – Tried and true, reliable, nice graphics.
    • Earl’s Models – Basic page with model graphics that you won’t find anywhere else.
    • Wunderground ECMWF Maps – The only source for free full-resolution ECMWF (European Model) maps. Color tables are… pathetic.

For Post-Event Analysis

  • NCDC Radar Archive – Look back at any weather event through the mid-1990s.
  • Iowa State Radar Archive – If you’re looking back at an event that occurred in the past 3 days, you can get your Level 2 radar data here.
  • SPC Mesoanalysis Archive – Looking for full-resolution SPC mesoscale analysis data from a past event? SPC might have it archived here.
  • University of Wyoming Soundings – Look up soundings from past events worldwide. The text files can be conformed to be used with SHARPpy.

International Links

Other Interesting Links

  • CIMSS Tropical Cyclones – Worldwide data for tropical cyclones.
  • Cyclone Phase Diagrams – Cool but very technical diagrams from FSU showing the evolution of cyclones.
  • MODIS Today – 250m resolution full-color satellite images of the CONUS taken twice daily by the Terra and Aqua POES (polar orbiting) satellites.
  • Worldwide MODIS Images – You can get MODIS images from around the world here, but they are not post-processed as well as in the link above.
  • FNMOC Tropical Cyclones – The Navy’s tropical cyclone page. Excuse the certificate error.
  • Scatterometer Data – See wind vectors over the ocean.