PLEASE NOTE: The file format described below refers to the Met Office Land Surface data (1900-2000) dataset which has been superseded by the Met Office MIDAS dataset (1853-present) at the BADC.
A list of UK stations for which the BADC holds .hwx files is available (.hwx stations).
The file name convention is (STATION_NAME)(YEAR).(MESSAGE_TYPE).(FILE_EXTENSION)
-999 indicates a missing value.
The first line of the data file is the fields headers (which are
detailed in the table below).
The fields in the .hwx data files are :
| HEADER | PARAMETER | FIELDS | COLUMNS | UNITS | COMMENTS |
|---|---|---|---|---|---|
| ID | Station Ref. Number | 1 | 1-8 | - | Station identification |
| IDTYPE | - | 2 | 9-17 | - | Station identification |
| MET_DOM | Meteorological Domain | 3 | 18-28 | - | Message types |
| YEAR | Year | 3 | 29-35 | - | 4 characters |
| MON | Month | 4 | 36-43 | - | 1 or 2 characters (from 1 to 12) |
| DAY | Day | 5 | 44-51 | - | 1 or 2 characters (from 1 to 31max) |
| HOUR | Hour | 6 | 52-59 | - | Hour of observation from 0 to 2300 |
| DIR | 10 minutes wind direction | 7 | 60-67 | Degree true | From 0 to 360 degrees, clockwise. Note that zero values in both wind speed and wind direction fields indicate that there was no wind blowing at the time of observation. See Met Office documentation |
| SPEED | 10 minutes wind speed | 8 | 68-75 | Knots | NB. A mean wind for the hour up until the reporting time. Note that zero values in both wind speed and wind direction fields indicate that there was no wind blowing at the time of observation. See Met Office documentation |
| PRST | Present weather | 9 | 76-81 | WMO Code | See Met Office documentation |
| PAS1 | Most significant Past weather | 10 | 82-87 | WMO code | See Met Office documentation |
| PAS2 | Least significant Past weather | 11 | 88-93 | WMO code | See Met Office documentation |
| TCA | Total cloud amount | 12 | 94-98 | WMO code | See Met Office documentation |
| LCT | Low cloud type | 13 | 99-103 | WMO Code | See Met Office documentation |
| MCT | Medium cloud type | 14 | 104-108 | WMO Code | See Met Office documentation |
| HCT | High cloud type | 15 | 109-113 | WMO Code | See Met Office documentation |
| CBA | Cloud base amount | 16 | 114-118 | WMO code | See Met Office documentation |
| CBH | Cloud base height | 17 | 119-126 | DAM | DAM = Decameters See Met Office documentation |
| VIS | Horizontal visibility | 18 | 127-133 | DAM | DAM = Decameters See Met Office documentation |
| MSLP | Mean Sea Level Pressure | 19 | 134-146 | 0.1 mb | Atmospheric pressure is expressed in millibars (1 millibar = 100 pascals = 100 newtons per square metre). Precision aneroid barometers are now in general use for measuring pressure and a correction for altitude is applied to obtain the value at mean sea level (MSL). |
| CA1 | Cloud amount - level 1 | 20 | 147-151 | WMO code | See WMO documentation |
| CT1 | Cloud type - level 1 | 21 | 152-156 | WMO code | See WMO documentation |
| CB1 | Cloud base - level 1 | 22 | 157-164 | DAM | DAM = decameters See WMO documentation |
| CA2 | Cloud amount - level 2 | 23 | 165-169 | WMO code | See WMO documentation |
| CT2 | Cloud type - level 2 | 24 | 170-174 | WMO code | See WMO documentation |
| CB2 | Cloud base - level 2 | 25 | 175-182 | DAM | DAM = Decameters See WMO documentation |
| CA3 | Cloud amount - level 3 | 26 | 183-187 | WMO code | See WMO documentation |
| CT3 | Cloud type - level 3 | 27 | 188-192 | WMO code | See WMO documentation |
| CB3 | Cloud base - level 3 | 28 | 193-200 | DAM | DAM = Decameters See WMO documentation |
| CA4 | Cloud amount - level 4 | 29 | 201-205 | WMO code | See WMO documentation |
| CT4 | Cloud type - level 4 | 30 | 206-210 | WMO code | See WMO documentation |
| CB4 | Cloud base - level 4 | 31 | 211-218 | DAM | DAM = Decameters See WMO documentation |
| VVIS | Vertical visibility | 32 | 219-226 | DAM | DAM = Decameters See Met Office documentation |
| TEMP | Dry-bulb air temperature | 33 | 227-234 | 0.1 Degrees Celsius | See Met Office documentation |
| DEW | Dew-point temperature | 34 | 235-242 | 0.1 Degrees Celsius | The dew point temperature (in degrees Celsius) is the temperature to which the air must be cooled to produce saturation with respect to water at its existing atmospheric pressure and humidity.See Met Office documentation |
| WETB | Wet-bulb temperature | 35 | 243-250 | 0.1 Degrees Celsius | The web-bulb temperature is the lowest temperature (in degrees Celsius) that can be obtained by evaporating water into the air. It measures the humidity of the air.See Met Office documentation |
| STNP | Station level pressure | 36 | 251-262 | 0.1 mb | Atmospheric pressure (in mb) as measured at the station level. Correction for altitude is not applied. |
| ALTP | Altimeter pressure | 37 | 263-270 | mb | - |
| SOG | State of ground | 38 | 271-275 | WMO Code | - |
| MGS | 10 minutes maximum gust speed | 39 | 276-283 | knots | See Met Office documentation |