Climatic Data Products / CD-ROM Products / ISMCS CD-ROM

SMOS Summary Table Content

TABLE 01 - SURFACE WINDS
TABLE 02 - CEILING Versus VISIBILITY
TABLE 03 - PSYCHROMETRIC SUMMARY
TABLE 04 - AIR TEMPERATURE Versus WIND DIRECTION
TABLE 05 - DAILY MAXIMUM TEMPERATURE
TABLE 06 - DAILY MINIMUM TEMPERATURE
TABLE 07 - DAILY MEAN TEMPERATURE
TABLE 08 - PRECIPITATION-DAILY AMOUNTS
TABLE 09 - SNOWFALL - DAILY AMOUNTS
TABLE 10 - SNOW DEPTH - DAILY AMOUNTS
TABLE 11 - SKY COVER
TABLE 12 - RELATIVE HUMIDITY
TABLE 13 - WEATHER CONDITIONS
TABLE 14 - WIND DIRECTION Versus WEATHER CONDITIONS
TABLE 15 - DRY BULB TEMPERATURE
TABLE 16 - WET BULB TEMPERATURE
TABLE 17 - DEWPOINT TEMPERATURE
TABLE 18 - SEA LEVEL PRESSURE
TABLE 19 - STATION PRESSURE
TABLE 20 - FLYING WEATHER
TABLE 21 - EXTREME PRECIPITATION AND SNOW AMOUNTS
TABLE 23 - EXTREME MONTHLY PRECIPITATION AMOUNTS
TABLE 24 - EXTREME MONTHLY SNOWFALL AMOUNTS
TABLE 25 - EXTREME MONTHLY SNOW DEPTH AMOUNTS
TABLE 27 - PEAK WIND GUSTS
TABLE 29 - DAILY AVERAGE AND EXTREME TEMPERATURES
TABLE 30 - EXTREME MAXIMUM TEMPERATURE
TABLE 31 - EXTREME MINIMUM TEMPERATURE
TABLE 32 - HEATING DEGREE DAYS
TABLE 33 - COOLING DEGREE DAYS
TABLE 34 - MEAN TEMPERATURE
TABLE 35 - TOTAL PRECIPITATION
TABLE 36 - ATMOSPHERIC PHENOMENON
TABLE 37 - STATION CLIMATIC SUMMARY
TABLE 40 - PSYCHROMETRIC STATISTICAL DATA
TABLE 42 - FOREIGN STATION CLIMATIC SUMMARY
TABLE 43 - HISTORICAL OCCURRENCE OF DAILY/WEEKLY/SEMI-MONTHLY PRECIPITATION
TABLE 44 - STATION CLIMATIC NARRATIVE

DATA TABLE DESCRIPTIONS, ELEMENTS, AND THRESHOLDS

This section defines the contents of each table produced during a SMOS processing run. The Table Number and Parameters are defined:

TABLE 01 - SURFACE WINDS

    Percentage Frequency of Wind Direction Versus Speed. Derived from hourly observations, these tabulations are a percentage frequency of wind directions to 16 compass points and calm by wind speeds (knots) in increments of Beaufort classifications. Percentages are shown by both direction and speed, and the mean wind speed for each direction. A separate category is provided on the form for variable winds, which are reported in some data sources. In these data where light and variable winds are reported with no directions but with speeds given, the speeds will be summarized in the appropriate groups opposite the column headed VARBL. The table also contains winds for all years combined: (a) By month - by standard 3-hour groups; (b) By month - all hours combined and; (c) Annual - all hours combined.

TABLE 02 - CEILING Versus VISIBILITY

    Percentage Frequency of Occurrence of Ceiling versus Visibility. This summary is a bivariate percentage frequency distribution by classes of ceiling from zero to equal to or greater than 20,000 feet and as a separate class "no ceiling", versus visibility in 16 classes from zero to equal to or greater than 10 miles. Data are derived from 3-hourly observations, and three sets of tables are presented as follows: (1) By Month - by standard 3-hour groups; (2) By Month - all years and all hours combined; or, (3) Annual - all years and all hours combined Due to the cumulative nature of this presentation, it is possible to determine the percentage frequency of occurrence for any given limit of ceiling or visibility separately, or in combination of ceiling and visibility. The totals progress to the right and downward. Ceiling may be determined independently by referring to totals in the extreme right hand column. Also, visibility may be determined independently by reference to the horizontal row of totals at the bottom of the page. The percentage frequency for which the station was meeting or exceeding any given set of minima may be determined from the figure at the intersection of the appropriate ceiling column and visibility row. Several examples in the use of these tables are shown on the following pages.
    NOTE: Beginning in July 1948 for U. S. Air Force stations and January 1949 for National Weather Service (NWS) and U.S. Navy stations the "no ceiling" category consists of observations with less than 6/10 total sky cover and those cases where total sky cover is 6/10 or more, but not more than 1/2 of the sky cover is opaque.

TABLE 03 - PSYCHROMETRIC SUMMARY

    Bi-variate Percentage Frequency Distribution and Computations of Dry-Bulb versus Wet-Bulb Temperature. This tabulation is derived from 3 hourly observations and is presented by month and annual, all hours and all years combined. The main body of the summary consists of a bivariate percentage frequency distribution of wet-bulb depression is 17 classes spread horizontally; by 2-degree intervals of dry-bulb temperature vertically. Also provided for each dry-bulb temperature interval is is the total number of observations with dry-bulb and wet-bulb temperature combined; and again for dry-bulb, wet-bulb and dew-point temperatures separately. Total observations for these four items is also provided in two lines at the end of each tabulation table.
    NOTE: 1. A percentage frequency in this table of ".0" represents one or more occurrences amounting to less than one tenth but greater than zero "0".
    NOTE: 2. Wet-bulb temperature usually was not reported prior to 1946. Relative humidity usually was not reported prior to 1949, nor subsequent to June 1958; and was computed by machine methods for observations recorded during these periods. All values of dew-point temperature and relative humidity are with respect to water unless otherwise indicated.

TABLE 04 - AIR TEMPERATURE Versus WIND DIRECTION

    Percentage Frequency of Air Temperature versus Wind Direction. This tabulation is derived from hourly observations and is presented by month and annual, all hours and years combined. The main body of the summary consists of dry bulb temperatures spread vertically in five degree increments and horizontally by eight wind directions (plus calm).

TABLE 05 - DAILY MAXIMUM TEMPERATURE

    Cumulative Percentage Frequency of Occurrence of Daily Maximum Temperature. Derived from daily observations and presented by month and annual for all years combined. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data. These tabulations provide the cumulative percentage frequency to tenths of temperature by 5-degree Fahrenheit increments, plus mean temperature, standard deviation, and total number of observations.

TABLE 06 - DAILY MINIMUM TEMPERATURE

    Cumulative Percentage Frequency of Occurrence of Daily Minimum Temperature. Derived from daily observations and presented by month and annual for all years combined. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data. These tabulations provide the cumulative percentage frequency to tenths of temperature by 5-degree Fahrenheit increments, plus mean temperature, standard deviation, and total number of observations.

TABLE 07 - DAILY MEAN TEMPERATURE

    Cumulative Percentage Frequency of Occurrence of Daily Mean Temperature. Derived from daily observations and presented by month and annual for all years combined. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data. These tabulations provide the cumulative percentage frequency to tenths of temperature by 5-degree Fahrenheit increments, plus mean temperature, standard deviation, and total number of observations.

TABLE 08 - PRECIPITATION-DAILY AMOUNTS

    Percentage Frequency of Precipitation of Various Daily Amounts. Presented by month and annual for all years combined. The percentage of days with measurable amounts is also computed monthly and annually. Also shown are the monthly mean amounts, annual mean amounts (sum of monthly mean amounts), and the extreme monthly amounts (greatest and least). Values are computed from daily observations.

TABLE 09 - SNOWFALL - DAILY AMOUNTS

    Percentage Frequency of Snowfall of Various Daily Amounts. Presented by month and annual for all years combined. The percentage of days with measurable amounts is also computed monthly and annually. Also shown are the monthly mean amounts, annual mean amounts (sum of monthly mean amounts), and the extreme monthly amounts (greatest and least). Values are computed from daily observations.

TABLE 10 - SNOW DEPTH - DAILY AMOUNTS

    Percentage Frequency of Snow Depth of Various Daily Amounts. Presented by month and annual for all years combined. The percentage of days with measurable amounts is also computed monthly and annually. Values are computed from daily observations.

TABLE 11 - SKY COVER

    Percentage Frequency Distribution of Total Sky Cover. This summary is prepared from 3-hourly observations and is a percentage frequency distribution of total sky cover (see Note 3) and total number of observations. It is presented as follows: By month and annual - by standard 3-hour groups, and all hours combined.
    NOTE: 1. Sky cover (total cloud amount) was not reported by U.S. Services until mid 1945. Data, when available, were punched for Air Force stations beginning in 1946, but were not available for Navy stations until 1948 or 1949. NWS stations recorded total cloud amount in remarks beginning sometime in 1945, but few stations have punched data prior to 1948. This summary will, of course, be limited to period of available data.
    NOTE: 2. Some data sources used for this summary report cloud amounts in oktas. These have been converted to tenths prior to summarizing, and notation is made on the form to indicate that data were originally reported in oktas. The manner of conversion is given below:

    OKTAS / TENTHS

        0 / 0
        1 / 1
        2 / 3
        3 / 4
        4 / 5
        5 / 6
        6 / 8
        7 / 9
        8 (or obscured) / 10

    NOTE: 3. Beginning in 1981 the symbols of Clear, Scattered, Broken, Overcast, and Obscured were used as input for the Total Sky Cover. Following are the conversions:

    0/10 equates to clear
    1/10 to 5/10 equates to scattered
    6/10 to 9/10 equates to broken
    10/10 equates to overcast

TABLE 12 - RELATIVE HUMIDITY

    Cumulative Percentage Frequency of Occurrence of Relative Humidity. This summary is derived from hourly observations and presents the cumulative percentage frequency of occurrence of relative humidity by increments of 10% classes, plus the mean relative humidity and total number of observations. Presented by month and annual - by standard 3-hour groups, and all hours combined with the hour groups being the vertical argument. All years are combined for this summary. NOTE: Wet-bulb temperature usually was not reported prior to 1946. Relative humidity usually was not reported prior to 1949, nor subsequent to June 1958; and was computed by machine methods for observations recorded during these periods. All values of dew-point temperature and relative humidity are with respect to water, unless otherwise indicated.

TABLE 13 - WEATHER CONDITIONS

    This summary is a percentage frequency occurrence of various atmospheric phenomena and obstructions to vision, derived from 3-hourly observations. Presented by month, all years combined, by standard 3-hour groups and all hours combined. Occurrences of the various phenomena included in each category are listed below:

    (a) Thunderstorms - All reported occurrences of thunderstorm, tornado, and waterspout.
    (b) Rain and/or Drizzle - All liquid precipitation, falling to the ground, not freezing.
    (c) Freezing Rain and/or Freezing Drizzle (Glaze) - Precipitation falling in liquid form, but freezing on contact with an unheated surface.
    (d) Snow and/or Sleet - Included are snow, sleet, snow pellets (soft hail), snow grains, and ice crystals.
    (e) Hail - Occurrences of hail and small hail are included.
    (f) Percentage of Observations with Precipitation.
    Included in this category are the observations when one or more of the above phenomena occurred. Since more than one type of precipitation may be reported in the same observation, the sums of the individual categories may exceed the total columns. (g) Fog - Included are fog, ice fog, and ground fog.
    (h) Smoke and/or Haze - Occurrences of smoke, haze, or combinations of smoke and haze are included.
    (i) Blowing Snow - Occurrences of blowing snow also drifting snow when reported from non-WBAN sources.
    (j) Dust and/or Sand - Included are blowing dust, blowing sand, and dust.
    (l) Percentage of Observations with Obstructions to Vision - Included in this category are the observations when one or more of the above obstructions to vision occurred. Since more than one type of obstruction may be reported in the same observation, the sums of the individual categories may exceed the percentage total columns. Also, although precipitation may reduce visibility, it is not considered an obstruction to vision for purposes of this summary; therefore, the percentage total of obstructions to vision need not reflect the total observations with reduced visibility.

    NOTE: 1. The total number of observations may vary among tables within the same month and period. Percentages may not always equal 100.0 due to rounding practices.

    NOTE: 2. A day with rain and/or drizzle was not separately reported in WBAN data prior to January 1949. Therefore percentages in this column are restricted to the period January 1949 and later.

    NOTE: 3. A day with dust and/or sand was punched and included in this summary only when visibility was less than 5/8 mile.

TABLE 14 - WIND DIRECTION Versus WEATHER CONDITIONS

    This summary is a percentage frequency occurrence of various atmospheric phenomena and obstructions to vision, derived from 3-hourly observations, and is presented by month and annual, all hours and years combined, by wind direction. Occurrences of the various phenomena included in each category are listed below:

    (a) Thunderstorms. All reported occurrences of thunderstorm, tornado, and waterspout.
    (b) Rain and/or Drizzle. All liquid precipitation, falling to the ground, not freezing.
    (c) Freezing Rain and/or Freezing Drizzle (Glaze). Precipitation falling in liquid form, but freezing on contact with an unheated surface.
    (d) Snow and/or Sleet. Included are snow, sleet, snow pellets (soft hail), snow grains, and ice crystals.
    (e) Hail. Occurrences of hail and small hail are included.
    (f) Fog. Included are fog, ice fog, and ground fog.
    (g) Smoke and/or Haze. Occurrences of smoke, haze, or combinations of smoke and haze are included.
    (h) Blowing Snow. Occurrences of blowing snow also drifting snow when reported from non-WBAN sources.
    (i) Dust and/or Sand. Included are blowing dust, blowing sand, and dust.
    (j) Blowing Spray. This item if reported, is not shown in a separate category on this table but is included with blowing sand or dust.

    NOTE: 1. The total number of observations may vary among tables within the same month and period. Percentages may not always equal 100.0 due to rounding practices.

    NOTE: 2. A day with rain and/or drizzle was not separately reported in WBAN data prior to January 1949. Therefore percentages in this column are restricted to the period January 1949 and later.

    NOTE: 3. A day with dust and/or sand was punched and included in this summary only when visibility was less than 5/8 mile.

TABLE 15 - DRY BULB TEMPERATURE

    Means and Standard Deviations of Dry Bulb Temperature. These tabulations are derived from hourly observations and present the mean, standard deviation, and total number of observations for the eight standard 3-hour groups, by month and annual and again at the bottom for all hours combined. Records for all years available are combined.

TABLE 16 - WET BULB TEMPERATURE

    Means and Standard Deviations of Wet Bulb Temperature. These tabulations are derived from hourly observations and present the mean, standard deviation, and total number of observations for the eight standard 3-hour groups, by month and annual and again at the bottom for all hours combined. Records for all years available are combined. Wet-bulb temperature were usually was not reported prior to 1946. NOTE: Wet-bulb temperature usually was not reported prior to 1946. Relative humidity usually was not reported prior to 1949, nor subsequent to June 1958; and was computed by machine methods for observations recorded during these periods. All values of dew-point temperature and relative humidity are with respect to water, unless otherwise indicated.

TABLE 17 - DEWPOINT TEMPERATURE

    Means and Standard Deviations of Dewpoint Temperature. These tabulations are derived from hourly observations and present the mean, standard deviation, and total number of observations for the eight standard 3-hour groups, by month and annual and again at the bottom for all hours combined. Records for all years available are combined.

    NOTE: Wet-bulb temperature were usually not reported prior to 1946. Relative humidity usually was not reported prior to 1949, nor subsequent to June 1958; and was computed by machine methods for observations recorded during these periods. All values of dew-point temperature and relative humidity are with respect to water, unless otherwise indicated.

TABLE 18 - SEA LEVEL PRESSURE

    Sea Level Pressure in Millibars. Presented are the means, standard deviations, and total number of observations of sea level pressure by month and annual for the local hourly observations corresponding to the eight 3-hourly synoptic times UTC. The same computations are also provided at the bottom of the page for all hours combined. All years of data available are combined in the table.

TABLE 19 - STATION PRESSURE

    Station Pressure in Inches of Mercury. Presented are the means, standard deviations, and total number of observations of station pressure by month and annual for the local hourly observations corresponding to the eight 3-hourly synoptic times UTC. The same computations are also provided at the bottom of the page for all hours combined. All years of data available are combined in the table.

TABLE 20 - FLYING WEATHER

    Flying Weather Expressed in Percent of Hours. Contained are subtables expressing monthly and annual percent of hours for various bi-variate and tri-variate threshold by three hourly and all hours combined of various flying weather conditions.

TABLE 21 - EXTREME PRECIPITATION AND SNOW AMOUNTS

    Precipitation, snowfall, and snow depth by individual month and day for the entire period of record available. Daily, monthly, and annual statistics are displayed.

TABLE 23 - EXTREME MONTHLY PRECIPITATION AMOUNTS

    Provides individual year and month extreme daily amounts and the means and standard deviations for each month and annual for all months combined. Values are computed from daily observations.

TABLE 24 - EXTREME MONTHLY SNOWFALL AMOUNTS

    Provides individual year and month extreme daily amounts and the means and standard deviations for each month and annual for all months combined. Values are computed from daily observations.

    NOTE: Hail was included in snowfall occurrence in the summary of the day observation prior to Jan 1956, and after Dec 1979.

TABLE 25 - EXTREME MONTHLY SNOW DEPTH AMOUNTS

    Provides individual year and month extreme daily amounts and the means and standard deviations for each month and annual for all months combined. Values are computed from daily observations.

    NOTE: Snow depth was recorded and key punched at various hours during the period available from U.S. operated stations. The periods and hours used in the snow depth summary vary by service and period as follows: U.S. Navy and Weather Bureau Stations: From beginning of record thru Jun 52: Snow depth at 0030 UTC; Jul 52 - May 57: Snow depth at 1230 UTC; Jun 57 - present: Snow depth at 1200 UTC

TABLE 27 - PEAK WIND GUSTS

    Extreme Values of Daily Peak Wind Gusts. Presented by speed in knots and direction from which the gust occurred by month and annual elements. Peak gust with direction, mean speed and standard deviation and total number of years of data are included. Values are computed from daily observations. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

TABLE 29 - DAILY AVERAGE AND EXTREME TEMPERATURES

    Derived from summary of the day observations and presented for each month and day for entire period of record available are average temperature, average and extreme maximum temperature, average and extreme minimum. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

TABLE 30 - EXTREME MAXIMUM TEMPERATURE

    Derived from daily observations with extreme value given for each year and month of record available. Extremes are provided for a month if all days for a month contain valid observations. All months for a year must have valid extremes before the ANNUAL value is selected for that year. Means and standard of daily extreme temperatures are presented. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

    NOTE: A supplementary list also provides extreme temperatures when less than a full month is reported.

TABLE 31 - EXTREME MINIMUM TEMPERATURE

    Derived from daily observations with extreme value given for each year and month of record available. Extremes are provided for a month if all days for a month contain valid observations. All months for a year must have valid extremes before the ANNUAL value is selected for that year. Means and standard of daily extreme temperatures are presented. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

    NOTE: A supplementary list also provides extreme temperatures when less than a full month is reported.

TABLE 32 - HEATING DEGREE DAYS

    Heating Degree Days from Daily Observations. Based on deviation from 65 degrees fahrenheit. Presented are monthly and annual values for individual years during the period of record. Values are computed from daily observations. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

TABLE 33 - COOLING DEGREE DAYS

    Cooling Degree Days from Daily Observations. Based on deviation from 65 degrees fahrenheit. Presented are monthly and annual values for individual years during the period of record. Values are computed from daily observations. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

TABLE 34 - MEAN TEMPERATURE

    Monthly and Annual Mean Temperatures. Presented are mean monthly and annual temperature values in fahrenheit for individual years during the period of record. Values are computed from daily observations. Telecommunications Summary version utilizes reported hourly values to compute extremes as daily values are unavailable in telecom data.

TABLE 35 - TOTAL PRECIPITATION

    Monthly and Annual Total Precipitation. Presented are total monthly and annual precipitation values in inches for individual years during the period of record. Values are computed from daily observations.

TABLE 36 - ATMOSPHERIC PHENOMENON

    This summary is a presentation of the percentage of days with occurrences of various atmospheric phenomena. The descriptions of the phenomena in the Weather Conditions Summary above also apply for the categories summarized in these tabulations. However, it should be noted that in this summary the columns headed "% OF OBS WITH PRECIP" and "% OF OBS WITH OBST TO VISION" show the percentage of days rather than percentage of observations. Since more than one type of precipitation or more than one type of obstruction may occur in the same daily observation, the sum of the values in the individual columns may not equal the total columns. This presentation is by month with annual totals, and is prepared with all years combined. Occurrences of the various phenomena included in each category are listed below:

    (a) Thunderstorms - All reported occurrences of thunderstorm, tornado, and waterspout.
    (b) Rain and/or Drizzle - All liquid precipitation, falling to the ground, not freezing.
    (c) Freezing Rain and/or Freezing Drizzle (Glaze) - Precipitation falling in liquid form, but freezing on contact with an unheated surface.
    (d) Snow and/or Sleet - Included are snow, sleet, snow pellets (soft hail), snow grains, and ice crystals.
    (e) Hail - Occurrences of hail and small hail are included.
    (f) Percentage of Observations with Precipitation. Included in this category are the observations when one or more of the above phenomena occurred. Since more than one type of precipitation may be reported in the same observation, the sums of the individual categories may exceed the total columns.
    (g) Fog - Included are fog, ice fog, and ground fog.
    (h) Smoke and/or Haze - Occurrences of smoke, haze, or combinations of smoke and haze are included.
    (i) Blowing Snow - Occurrences of blowing snow also drifting snow when reported from non-WBAN sources.
    (j) Dust and/or Sand - Included are blowing dust, blowing sand, and dust.
    (l) Percentage of Observations with Obstructions to Vision - Included in this category are the observations when one or more of the above obstructions to vision occurred. Since more than one type of obstruction may be reported in the same observation, the sums of the individual categories may exceed the percentage total columns. Also, although precipitation may reduce visibility, it is not considered an obstruction to vision for purposes of this summary; therefore, the percentage total of obstructions to vision need not reflect the total observations with reduced visibility.

    NOTE: 1. The total number of observations may vary among tables within the same month and period. Percentages may not always equal 100.0 due to rounding practices.

    NOTE: 2. A day with rain and/or drizzle was not separately reported in WBAN data prior to January 1949. Therefore percentages in this column are restricted to the period January 1949 and later.

    NOTE: 3. A day with dust and/or sand was punched and included in this summary only when visibility was less than 5/8 mile.

TABLE 37 - STATION CLIMATIC SUMMARY

    A variety of temperature, wind, and atmospheric phenomena statistics are presented for monthly and annual values. Monthly data for the period of record are combined to produce annual values. Temperature values are in degrees fahrenheit. Precipitation values are in presented in inches. Wind speeds are in knots. Sky cover conditions are based on clear, scattered, broken, and overcast conditions converted from 10th of sky cover for domestic (AIRWAYS) reporting stations and 8th of sky cover for foreign (METAR) reporting stations.

    NOTE: Detailed explanations on statistical computations and data limitations of individual elements are contained in individual table descriptions.

TABLE 40 - PSYCHROMETRIC STATISTICAL DATA

    Statistical Data for the Individual Elements of Relative Humidity, Dry-bulb, Wet-bulb, and Dew-point Temperatures. This tabulation is derived from 3 - hourly observations and is presented by month and annual, all hours and all years combined. Shown in the section at the bottom left of each page are the sum of squares ( X ), sums of values ( X), means ( X ), and standard deviations ( X ). The number of observations used in the computations for each element is also shown.

    NOTE: Wet-bulb temperature usually was not reported prior to 1946. Relative humidity usually was not reported prior to 1949, nor subsequent to June 1958; and was computed by machine methods for observations recorded during these periods. All values of dew-point temperature and relative humidity are with respect to water, unless otherwise indicated.

TABLE 42 - FOREIGN STATION CLIMATIC SUMMARY

    A variety of temperature, wind, and atmospheric phenomena statistics are presented for monthly and annual values. Monthly data for the period of record are combined to produce annual values. Temperature values are in degrees fahrenheit. Precipitation values are not presented. Only precipitation probabilities are presented. Wind speeds are in knots. Sky cover conditions are based on clear, scattered, broken, and overcast conditions converted from 10th of sky cover for domestic (AIRWAYS) reporting stations and 8th of sky cover for foreign (METAR) reporting stations.

    NOTE: Detailed explanations on statistical computations and data limitations of individual elements are contained in individual table descriptions.

TABLE 43 - HISTORICAL OCCURRENCE OF DAILY / WEEKLY / SEMI-MONTHLY PRECIPITATION

    This table provides a monthly historical summary, by day, week, and semi-monthly of mean precipitation, percent occurrence of days with precipitation, maximum and minimum precipitation amounts and number of occurrences. Mean precipitation is for days when precipitation occurred.

TABLE 44 - STATION CLIMATIC NARRATIVE

    This table provides a brief overview of selected observation station climatic influences.