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Forecast for Unknown Site (4.895 E 52.370 N)


Icon Definition

Icon Technical Definition
Octet-gram of cloud cover, blue is for clear while white is for cloud. e.g. the "cake" on the left is 0% cloud while the one on the right is 100% cloud.
Astronomical seeing. From left to right: <0.5", 0.5"-0.75", 0.75"-1", 1"-1.25", 1.25"-1.5", 1.5"-2", 2"-2.5", >2.5". In short, the smaller/bluer, the better the seeing condition is.
Atmospheric transparency. From left to right: <0.3, 0.3-0.4, 0.4-0.5, 0.5-0.6, 0.6-0.7, 0.7-0.85, 0.85-1, >1 (unit: mag per air mass). In short, the fewer bars/bluer, the better the transparency is.
Chances of rain/snow.
Atmospheric instability. From left to right: lifted index between 0 to -3, -3 to -5, and below -5.
Humid weather warning. From left to right: relative humidity between 80%-90%, 90%-95%, and over 95%.
Windy weather warning. From left to right: sustained wind speed between 8.0-10.8m/s (fresh), 10.8-17.2m/s (strong), and over 17.2m/s (gale or above).

For more details, please refer to the corresponding chapter in the Documentation.



Application Programming Interface (API)

Graphical API

The graphical API will display the forecast diagram as seen at the 7Timer! website, this is useful for website makers who wish to include the forecast diagram in their websites. The graphical API address for this location would be

http://www.7timer.com/v4/bin/astro.php?lon=4.895&lat=52.37&lang=en&ac=0&unit=metric&tzshift=0

The graphical API, when properly called, will return a PNG-type image, so you may use <img> tag to include the forecast diagrams in your website.

Machine-readable API

The machine-readable API will produce a set of data that can be used directly by application. We now offer API in both Extensible Markup Language (XML) and JavaScript Object Notation (JSON) standard. The API address for this location is:

XML: http://www.7timer.com/v4/bin/api.pl?lon=4.895&lat=52.37&product=astro&output=xml
JSON: http://www.7timer.com/v4/bin/api.pl?lon=4.895&lat=52.37&product=astro&output=json

A brief explanation of the parameters is given below:

lon, lat – Geographic coordinates of the specified site.
ac – Altitude Correction, only applicable in ASTRO forecast. Should be 0 (default), 2 or 7. Not applicable to the machine-readable APIs.
lang – Language. Not applicable in METEO forecast and the machine-readable APIs..
unit – Metric or British. Not applicable to the machine-readable APIs.
output – should be xml or json (for machine-readable APIs).
tzshift – Adjustment of timezone. Not applicable to the machine-readable APIs.
product – Product selection for machine-readable APIs. Should be astro, civil, civillight, meteo or two.

A successful call of the API will return sets of values. For exact meaning of these values, please refer to the corresponding chapther in Documentation.


Term of Use

You may use these data freely as long as the purpose is noncomercial. Program developers are asked to notify me when using the service so I can track the server workload. Please remember that weather forecast is one of the most highly challenging problems in our times, so using these data is at your own risk.


Find a Location by Coordinates

If you have already know the geographic coordinates of a location, you may enter them to get forecast. Coordinates must be input as "dd.ddd/-dd.ddd", like "113.190,23.094 or -113.190,-23.094", with precision up to 0.001.

Longitude: Latitude:

7Timer! is proudly supported by Chinese Network for Astronomy Popularization at Shanghai Astronomical Observatory, Chinese Academy of Sciences.