Degree-Day Map Maker
US Degree-Day Mapmaker

Calculator Options:   Thresholds: ° F.  lower:  upper:   calc. type:   start date:  end date:   data from:
Mapping Options:  Region:  Subregion-(not New Eng states):  Mapsize:  Image type:  Legend:  Resolution:  Network Selection:  Overlay:

Instructions - how to make degree-day maps
New Version 4.5 - improved resolution, better subregion support, network selection, and GIS data downloads
   1. Be sure to read the documentation pages before starting
   2. Select calculator options (similar to a site-only calculator), and mapping options (particularly Region)
   3. Note that the "Subregion" option is only valid for non-New England states (is not valid for ME, VT, NH, CT,
      RI, NJ, or DL)
   4. Note that the "Resolution" option should only be used for small regions and states, and slows down processing.
      This option is experimental and may not provide an improved map. Use with caution.
   5. The new "Network Selection" option allows: a) faster processing "include selected networks (fewest stations)",
      b) fewer "bullseye anomalies" (fewer mis-aligned weather stations, c) allows for the possible need
       for greater detail offerred by picking "all networks". Default currently set for fewest stations,
       which currently is set to the following networks: METAR (ASOS), AGRIMET, HYDROMET, RAWS,
   6. Click on MAKE MAP button - typically takes 40+ seconds for a western state
      if you get an error, try:
       a) using a different web browser (Firefox recommended),
       b) again after a few minutes, or
       c) letting us know about the error (see email link below)
   7. Conditions not currently supported include:
       a) degrees Celsius (only Fahrenheit is supported)
       b) calculations that need data in the future
       c) for eastern states - years before 2005
   8. When map is finished, the GRASSLinks button will appear. Click on this to see and interact with the map
       (ca. 4-12 seconds additional wait time)
   9. A separate legend window will also open (requires javascript support)
   10. Optional - download zipped GIS data (arc ascii format)
[Home] [Intro] [Data Access Maps] [DD Calc & Models] [Links]
National Plant Diagnostics Network Integrated Plant Protection Center at OSU Oregon State University The PRISM Group at OSU Western
 Region Pest Management Center National Institute
 for Food and Agriculture

This project funded in part by grants by several USDA-NIFA programs, USDA-APHIS-PPQ-CPHST,
and by the statewide Integrated Pest Management Program of IPPC at Oregon State University.

This program on-line since Dec 9, 1998 Last updated Jan. 12, 2016 version 4.53
Contact Len Coop at if you have any questions about this information.