Weather Warnings

All weather warning parameters are inspired by the descriptions of the DWD.

Frost Warning

The frost parameter depicts whether the temperature at a height of 2 meters falls below 0 degrees Celsius.

The frost warning corresponds to the US freezing warning, which is issued when surface temperatures are expected to drop below freezing (32 degrees Fahrenheit). The US frost definition corresponds to the definition of ground frost, which describes the formation of thin ice crystals on the ground or other surfaces when the temperatures of the Earth's surface falls below 32 degrees Fahrenheit.

frost_warning_<interval>:idx

Available intervals: 1h, 2h, 3h, 6h, 12h, 24h

Warning	Description	Temperature Limits
0	No frost	> 0°C
1	Frost	≤ 0°C and > -10°C
2	Severe Frost	≤ -10°C

Example:

Surface temperature along with the frost warning index for the end of March/beginning of April, 2020 in St. Gallen:

Current Situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-22T00:00:00Z:PT1H/frost_warning_1h:idx,t_0m:C/47.412164,9.340652/html

Heavy Rain Warning

This parameter indicates if any heavy rain events will occur in a given time interval.

heavy_rain_warning_<interval>:idx

Available intervals: 1h, 2h, 3h, 6h, 12h, 24h

Warning	Description	Limits for `1h`	Limits for `6h`
0	No severe rainfall	< 15mm	< 20mm
1	Heavy Rainfall	15mm to 25mm	20 mm to 35mm
2	Severe Heavy Rainfall	25mm to 40mm	35 mm to 60mm
3	Extreme Heavy Rainfall	> 40mm	> 60mm

Example:

Severe heavy rainfall in St. Gallen on August 2^nd, 2018:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-20T00:00:00Z:PT6H/heavy_rain_warning_6h:idx,precip_6h:mm/47.4245,9.3767/html?source=mix

Incessant Rain Warning

This parameter indicates if any incessant rain events will occur in a given time interval. A rain event is defined incessant if it lasts for at least 60 minutes.

incessant_rain_warning_<interval>:idx

Available intervals: 12h, 24h, 48h, 72h

Warning	Description	Limits for `12h`	Limits for `24h`	Limits for `48h`	Limits for `72h`
0	No incessant rainfall	< 25mm	< 30mm	< 40mm	< 60mm
1	Incessant Rainfall	25mm to 40mm	30mm to 50mm	40mm to 60mm	60mm to 90mm
2	Severe Incessant Rainfall	40mm to 70mm	50mm to 80mm	60mm to 90mm	90mm to 120mm
3	Extreme Incessant Rainfall	> 70mm	> 80mm	> 90mm	> 120mm

Example:

Severe incessant rainfall in St. Gallen on June 12^th, 2019:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-20T00:00:00Z:PT12H/incessant_rain_warning_12h:idx,precip_12h:mm/47.4245,9.3767/html?source=mix

Snow Warning

This parameter indicates if any severe snow fall will occur in a given time interval.

snow_warning_<interval>:idx

Available intervals: 1h, 2h, 3h, 6h, 12h, 24h, 48h

Warning	Description	Limits for `1h`	Limits for `6h`	Limits for `12h`	Limits for `24h`	Limits for `48h`
0	No severe snowfall	< 1cm
1	Snowfall	< 1cm	< 5cm	< 10cm	< 15cm	< 20cm
2	Snowfall	below 800m: 1cm to 2cm above 800m: 1cm to 4cm	below 800m: 5cm to 10cm above 800m: 5cm to 20cm	below 800m: 10cm to 15cm above 800m: 10cm to 30cm	below 800m: 15cm to 30cm above 800m: 15cm to 40cm	20cm to 50cm
3	Heavy Snowfall	below 800m: 2cm to 4cm above 800m: 4cm to 6cm	below 800m: 10cm to 20cm above 800m: 20cm to 30cm	below 800m: 15cm to 25cm above 800m: 30cm to 50cm	below 800m: 30cm to 40cm above 800m: 40cm to 60cm	50cm to 70cm
4	Extreme Heavy Snowfall	below 800m: > 4cm above 800m: > 6cm	below 800m: > 20cm above 800m: > 30cm	below 800m: > 25cm above 800m: > 50cm	below 800m: > 40cm above 800m: > 60cm	> 70cm

Example:

Severe snow fall event on Säntis on October 6^th, 2019:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-20T00:00:00Z:PT1H/snow_warning_1h:idx,fresh_snow_1h:cm/47.249349,9.342348/html?source=mix

Wind Warning

This parameter indicates if any dangerous wind speeds will occur in a given time interval. Wind speeds are considered dangerous if they exceed 50 km/h.

wind_warning_<interval>:idx

Available intervals: 1h, 2h, 3h, 6h, 12h, 24h

Warning	Description	Limits
0	No severe wind conditions	< 50km/h
1	Wind Gusts	50km/h to 64km/h
2	Squall	65km/h to 89km/h
3	Severe Squall	90km/h to 104km/h
4	Violent squall	105km/h to 119km/h
5	Gale-Force Winds	120km/h to 139km/h
6	Extreme Gale-Force Winds	> 140km/h

Example:

Severe wind speeds with a warning of 5 at the North Sea on February 9^th, 2020:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-20T00:00:00Z:PT1H/wind_warning_1h:idx,wind_gusts_10m_1h:kmh/53.711657,7.889181/html?source=mix

Fog Warning

This parameter indicates if any fog will occur in an interval of one hour.

fog_warning_1h:idx

Warning	Description	Criteria
0	No fog
1	Fog	The visibility has been less than 150 m in the past hour

Example:

Fog warning around Cremona, Italy on November 3^rd, 2023:
https://api-mm.ncm.gov.sa/2023-11-02T00:00:00Z--2023-11-02T10:30:00Z:PT1H/fog_warning_1h:idx/45,10/html?source=mix

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-22T00:00:00Z:PT1H/fog_warning_1h:idx/45,10/html?source=mix

Example:

Fog warning for Northern Europe on the 7^th of March, 2024 plotted with MetX.

Thunderstorm Warning

This parameter indicates if any thunderstorms will occur in a given time interval.

tstorm_warning_<interval>:idx

Available intervals: 1h, 2h, 3h, 6h, 12h, 24h

Warning	Description	Criteria
0	No thunderstorms
1	Thunderstorm	Occurrence of electric discharge
2	Heavy thunderstorm	Occurrence of electric discharge in combination with strong gale, heavy rain or hail
3	Severe thunderstorm	Occurrence of electric discharge in combination with strong gale, heavy rain or hail where at least on accompanying feature has warning level
4	Severe thunderstorm with extreme squalls and heavy rainfall	Occurrence of electric discharge in combination with strong gale, heavy rain or hail where at least on accompanying feature has alerting level

Example:

Thunderstorm warning of 4 around Munich with corresponding lightning strikes on June 22^nd, 2019:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z--2025-07-22T00:00:00Z:PT1H/tstorm_warning_1h:idx,precip_1h:mm/47.412164,9.340652/html?source=mix

Satellite-based Thunderstorm Warning

Satellite-based parameter for detection of thunderstorms. The index provides values between 0 and 3:

sat_storm_warning:idx

Value	Meaning
0	No storm cells present
1	Storm cells present
2	Heavy thunderstorms
3	Severe thunderstorms

Example:

Thunderstorm warning on April 9^th, 2021:

Current situation:
https://api-mm.ncm.gov.sa/2025-07-17T00:00:00Z/sat_storm_warning:idx/60,-12_35,30:0.05,0.05/html_map