Global Surface Summary of the Day is derived from The Integrated Surface Hourly (ISH) dataset. The ISH dataset includes global data obtained from the USAF Climatology Center, located in the Federal Climate Complex with NCDC. The latest daily summary data are normally available 1-2 days after the date-time of the observations used in the daily summaries. The online data files begin with 1929 and are at the time of this writing at the Version 8 software level. Over 9000 stations' data are typically available. The daily elements included in the dataset (as available from each station) are: Mean temperature (.1 Fahrenheit) Mean dew point (.1 Fahrenheit) Mean sea level pressure (.1 mb) Mean station pressure (.1 mb) Mean visibility (.1 miles) Mean wind speed (.1 knots) Maximum sustained wind speed (.1 knots) Maximum wind gust (.1 knots) Maximum temperature (.1 Fahrenheit) Minimum temperature (.1 Fahrenheit) Precipitation amount (.01 inches) Snow depth (.1 inches) Indicator for occurrence of: Fog, Rain or Drizzle, Snow or Ice Pellets, Hail, Thunder, Tornado/Funnel Cloud Global summary of day data for 18 surface meteorological elements are derived from the synoptic/hourly observations contained in USAF DATSAV3 Surface data and Federal Climate Complex Integrated Surface Hourly (ISH). Historical data are generally available for 1929 to the present, with data from 1973 to the present being the most complete. For some periods, one or more countries' data may not be available due to data restrictions or communications problems. In deriving the summary of day data, a minimum of 4 observations for the day must be present (allows for stations which report 4 synoptic observations/day). Since the data are converted to constant units (e.g, knots), slight rounding error from the originally reported values may occur (e.g, 9.9 instead of 10.0). The mean daily values described below are based on the hours of operation for the station. For some stations/countries, the visibility will sometimes 'cluster' around a value (such as 10 miles) due to the practice of not reporting visibilities greater than certain distances. The daily extremes and totals--maximum wind gust, precipitation amount, and snow depth--will only appear if the station reports the data sufficiently to provide a valid value. Therefore, these three elements will appear less frequently than other values. Also, these elements are derived from the stations' reports during the day, and may comprise a 24-hour period which includes a portion of the previous day. The data are reported and summarized based on Greenwich Mean Time (GMT, 0000Z - 2359Z) since the original synoptic/hourly data are reported and based on GMT.

The dataset consists primarily of U.S. surface airways observations (SAO) data beginning in 1965 and extending through 1981. Note that a few stations have already had certain years within this 1965-81 period re-keyed as hourly. For these stations, only a subset of the period was keyed. In addition, other stations did not have data keyed at all during this period, or during the periods immediately before or after the 1965-81 range. These stations data have been keyed to as thoroughly as possible complete their entire period of record back to July, 1948. The major data variables are as follows: WBAN Identification Station Number, observational type, ceiling and cloud, visibility, present weather, temperature, relative humidity, wind, pressure and precipitation. The observations are generally recorded for the 24 hour period midnight to midnight. The keying format was designed to reflect the data as entered on the page to make keying easier for the key entry personnel, who were not trained meteorological technicians. The "raw" observations which comprise this dataset will be quality checked to include data adjustments and converted to NCDC's Integrated Surface Hourly (ISH) format.

The dataset consists primarily of U.S. surface airways observations (SAO) data beginning in 1965 and extending through 1981. Note that a few stations have already had certain years within this 1965-81 period re-keyed as hourly. For these stations, only a subset of the period was keyed. In addition, other stations did not have data keyed at all during this period, or during the periods immediately before or after the 1965-81 range. These stations data have been keyed to as thoroughly as possible complete their entire period of record back to July, 1948. The major data variables are as follows: WBAN Identification Station Number, observational type, ceiling and cloud, visibility, present weather, temperature, relative humidity, wind, pressure and precipitation. The observations are generally recorded for the 24 hour period midnight to midnight. The keying format was designed to reflect the data as entered on the page to make keying easier for the key entry personnel, who were not trained meteorological technicians. The "raw" observations which comprise this dataset will be quality checked to include data adjustments and converted to NCDC's Integrated Surface Hourly (ISH) format.

The dataset consists of hourly U.S. surface airways observations (SAO). These observations extend as far back as 1928, from the time when commercial aviation began in the United States and meteorological observing stations were established at many airports (although occasionally, early-period SAO's were taken at U.S. Weather Bureau city offices). For most stations, this dataset extends through June of 1948. The major data variables are as follows: WBAN Station Identification Number, observational type, ceiling and cloud, visibility, present weather data, temperature, wind and pressure. The observations are generally recorded for the 24-hour period midnight to midnight, although many stations did not record 24-hour observations, especially early in the period when commercial aviation was just getting started. Two output keying formats were created to adjust to an observational form change during the period. One format was generally used for years 1928-33, and the other for sets from around 1934 through June of 1948. Each keying format was designed to reflect the data as entered on the observational form for ease of keying by key entry personnel, who were not trained meteorological technicians. The "raw" observations which comprise the DSI-3851 dataset were quality checked, to include data adjustments, and converted to NCDC's Integrated Surface Hourly (ISH) format. The complimentary data to this collection can be found in the Surface Weather Observation 1001 Forms (Keyed) collection.

The Global Hourly Summaries are simple indicators of observational normals which include climatic data summarizations and frequency distributions. These typically are statistical analyses of station data over 5-, 10-, 20-, 30-year or longer time periods. In a GIS map service, the results of these calculations are represented by a given symbology set for different statistical criteria and observation type. Having the ability to modify the symbology "on-the-fly" is a useful tool in the analysis of station trends, accuracy, and regional or localized variances. The summaries are computed from the global surface hourly dataset. This dataset totaling over 350 gigabytes is comprised of 40 different types of weather observations with 20,000 stations worldwide. NCDC and the U.S. Navy have developed these value added products in the form of hourly summaries from many of these observations. These data are a subset of the Integrated Surface Hourly dataset (DSI-3505) (C00532).

The Global Hourly Summaries are simple indicators of observational normals which include climatic data summarizations and frequency distributions. These typically are statistical analyses of station data over 5-, 10-, 20-, 30-year or longer time periods. In a GIS map service, the results of these calculations are represented by a given symbology set for different statistical criteria and observation type. Having the ability to modify the symbology "on-the-fly" is a useful tool in the analysis of station trends, accuracy, and regional or localized variances. The summaries are computed from the global surface hourly dataset. This dataset totaling over 350 gigabytes is comprised of 40 different types of weather observations with 20,000 stations worldwide. NCDC and the U.S. Navy have developed these value added products in the form of hourly summaries from many of these observations. These data are a subset of the Integrated Surface Hourly dataset (DSI-3505) (C00532).

Local Climatological Data (LCD) contains summaries from major airport weather stations that include a daily account of temperature extremes, degree days, precipitation amounts and winds. Also included are the hourly precipitation amounts and abbreviated 3-hourly weather observations. This is the final quality controlled copy and generally has a one to two month time lag. The local climatological data annual file is produced from the National Weather Service (NWS) first and second order stations. These data are contained in the LCD monthly and annual publications. The monthly summaries include maximum, minimum, and average temperature, temperature departure from normal, dew point temperature, average station pressure, ceiling, visibility, weather type, wet bulb temperature, relative humidity, degree days (heating and cooling), daily precipitation, average wind speed, fastest wind speed/direction, sky cover, and occurrences of sunshine, snowfall and snow depth. The annual summary with comparative data contains monthly and annual averages of the above basic climatological data in the meteorological data for the current year section, a table of the normals, means, and extremes of these same data, and sequential table of monthly and annual values of average temperature, total precipitation, total snowfall, and total degree days. Also included is a station location table showing in detail a history of, and relative information about, changes in the locations and exposure of instruments. The NCDC also archives a Preliminary Local Climatological Data manuscript that contains similar information, but is not quality controlled.

The CLAVR-1 cloudmask (Stowe, 1999) is used to cloudmask AVHRR high resolution sea surface temperature products. The cloudmask runs a series of tests on each surface temperature pixel to determine whether the pixel is contaminated by cloud cover. Users may evaluate which specific tests in the cloudmask returned positive cloud presence results by examining the value of the cloudmask. This value corresponds to an 8 bit binary number which details which tests flagged the pixel as a cloudy pixel. See https://coastwatch.pfeg.noaa.gov/info/CLAVR.html for more information regarding the specific tests used in the cloudmask.

Summary of the Day Observations - Misawa Japan is a collection of data summarizing daily weather observations taken at Misawa Naval Air Station, near the north end of the main Japanese island of Honshu. It consists of a single ASCII file containing the period of record 9 April 1948 through 31 December 1971. Elements include daily rainfall, snowfall, snow depth, snow water equivalent, humidity, maximum/minimum/mean temperature, peak wind gust/direction/time, and number of hours in which fog was present.

Summary of the Day Observations - Misawa Japan is a collection of data summarizing daily weather observations taken at Misawa Naval Air Station, near the north end of the main Japanese island of Honshu. It consists of a single ASCII file containing the period of record 9 April 1948 through 31 December 1971. Elements include daily rainfall, snowfall, snow depth, snow water equivalent, humidity, maximum/minimum/mean temperature, peak wind gust/direction/time, and number of hours in which fog was present.