| Resource | time |
| Command Line | -ft=time |
| Environment Variable | wxptime |
| Default Value | User prompt |
This resource is used to specify the forecast time. This is often used with model data but can be used with observed data to specify a range of time or accumulation. There are several ways to specify the forecast time. The syntax is:
time[-range][type]
You can specify a time by using entering the time and its units:
| Value | Description |
| init | Initial time |
| anal | analysis |
| 12hr | 12 hour forecast |
| h12 | 12 hour forecast |
| 2day | 2 day forecast |
| d2 | 2 day forecast |
| 4.5day | 4 1/2 day forecast |
| e4 | 4 1/2 day forecast |
| time | use the value of the time resource (useful in var files) |
| miss | missing value, take first available |
The range is an hour range which is followed by the type of range. The types of ranges are:
| Value | Description |
| rng | range |
| avg | average |
| acc | accumulation |
| dif | difference |
This leads to several possible combinations:
| Value | Description |
| anal-12acc | 12 hour accumulation up to analysis time or 12 hour observed accumulation. |
| anal-24dif | 24 hour difference between current and previous 24 hours. |
| 24hr-12acc | 12 hour accumulation up to the 24 hour forecast time. |
| time-12acc | 12 hour accumulation up to time specified in time resource (used in var files). |
Often gridded model data is specified with a complex time. The time and range syntax is a way of solving the problem of accessing these grids. A simpler way is to specify only the valid time.
-ft=24hr
-ft=24hr-12acc
The GRIB search algorithm will find the first grid with that valid time. The more verbose method will also work if there is more than one grid matching the same valid time.
For further information about WXP, email technical-support@weather.unisys.com
Last updated by Dan Vietor on July 30, 1998