Station data Return to main page
Data are observations from stations throughout North America.
For each station all available data from the months November, December, January, February, and March (NDJFM) of the years 1948-1997 are used for analysis.
Data sets used in this work:
- Canada
- Provided by Amir Shabbar of the University of Toronto
- Over 500 stations; ~60 have only temperature data, ~350 have only precipitation data, ~150 have both temperature and precipitation data
- Available station records are generally mostly complete, meaning that overall the number of winter days over the period of interest missing observations tends to be small, though it varies from station to station
- HCND
- United States Historical Climatology Network Daily Temperature and Precipitation Data
- Over 1000 stations with temperature and precipitation data
- Station records are mostly very nearly complete for temperature data but tend to be only about 75% complete for precipitation data
- COOP
- National Weather Service's Cooperative Station Network
- Over 15000 stations with some amount of data
- Wide range in station records - many nearly complete, many with almost no data, many somewhere between
Extreme weather Return to main page
In this analysis dealing only with temperature and precipitation, "extreme weather" refers only to days that are unusually cold or warm or that have a significant amount of precipitation. This term may invoke ideas of tornadoes, hail, wind storms, etc., but though those things may definitely be considered extreme, they are not part of this work.
Teleconnections Return to main page
What this work aims to show Return to main page
About the regions Return to main page
The Canada and HCND data sets are national in scope and probably not likely to be protested. For storage and processing purposes the very large COOP data set was broken down into separate regions, but the region definitions and in which region some states were placed might be questioned. The regions were determined arbitrarily aiming to produce results with at least some geographic coherence and of approximately equal size (except for the small COOP Alaska, which was originally included in COOP Northwest).
Minor web browser requirements Return to main page
Because there are so many total web pages involved with this work, they were designed in general to be not highly sophisticated. However, to get the full use of this archive a web browser should be capable of the following two things:
- Javascript enabled - to open and close windows for maps, graphs, and other figures and to utilize navigation menus
- Show more than just the 216 fundamental WWW colors - to clearly show the color scheme designed for distinguishing analysis results