User's Manual for TMY2s

Table of Contents

Section 1   Overview



There are 239 TMY2 stations for the United States and its territories. These are the same stations as for the NSRDB, from which the TMY2 data sets were derived. The stations are National Weather Service stations that collected meteorological data for the period of 1961-1990. Table 2-1 lists the stations by state or territory and provides information describing the station location and the NSRDB and TMY2 classifications.

Compared to the SOLMET/ERSATZ TMYs, there is a net gain of five stations, and some of the station locations have changed. The TMY2 data sets include 37 new stations, but 32 previous SOLMET/ERSATZ TMY stations were not included because these stations were not included in the NSRDB.


The station locations are described in Table 2-1 by the city and state name, the station Weather Bureau Army Navy (WBAN) identification number, the latitude and longitude in degrees and minutes, and the elevation in meters.

NSRDB Classification

Stations are classified with respect to being NSRDB primary (P) or secondary (S) stations. The 56 primary stations measured solar radiation for a part (from 1 to 27 years) of the 30-year period of 1961-1990. The remaining 183 secondary stations made no solar radiation measurements and therefore use modeled solar radiation data that are derived from meteorological data such as cloud cover.

TMY2 Classification

This classification pertains to the amount of measured meteorological data available for a station to select typical months to form the typical meteorological year. Class A stations, of which there are 216, had a minimum of 15 candidate months without more than 2 consecutive hours of missing data. For the 23 Class B stations to achieve a minimum of 15 candidate months, data filling for periods of up to 47 hours were required. For some elements not required for the selection of the typical meteorological months, the data are unfilled in the TMY2 data files. The elements horizontal visibility, ceiling height, and present weather may be missing for up to 2 consecutive hours for Class A stations and for up to 47 hours for Class B stations. No data are missing for more than 47 hours, except for snow depth and days since last snowfall for Colorado Springs, Colorado.

Section 3   Data and Format

Table of Contents

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