OFFICIAL NOTICE & DISCLAIMER: South Island Meteorological Agency (SIMA) is an independent, private forecaster. SIMA is not a government agency and is not affiliated, connected, or partnered with MetService or Civil Defence (NEMA).
Our operational outlooks and regional insights do not constitute official government severe weather warnings. To view official New Zealand watches, warnings, and severe weather outlooks, please visit MetService Severe Weather Warnings.
About Us
South Island Meteorological Agency (SIMA) is a private, independent regional weather service dedicated to providing secondary weather guidance and localised insights across the South Island of New Zealand.
We provide specialised regional forecasts for high-impact conditions, including convective storm potential (StormCast), snowfall distribution (SnowCast), and long-range moisture trends (DroughtCast). Our team utilises open-access numerical models and localised geographic knowledge to provide accessible information for our community.
Significant Weather Criteria
Our Significant Weather Outlook maps outline the likelihood of notable weather events occurring across specific South Island regions over the next 5 days. Risk categories indicate our forecasting confidence and the localised probability of impactful weather.
| RISK LEVEL | LIKELIHOOD & EXPECTATIONS |
|---|---|
| Slight Risk |
Likelihood: Low probability (10% to 30% chance) of significant weather within the highlighted area. Conditions suggest isolated or weak activity is possible, but confidence remains low. General weather awareness is encouraged. |
| Enhanced Risk |
Likelihood: Moderate probability (30% to 50% chance) of significant weather within the highlighted area. Atmospheric conditions favour elevated activity. Localised impacts may occur across parts of the highlighted region. |
| High Risk |
Likelihood: High probability (greater than 50% chance) of significant weather within the highlighted area. Strong atmospheric confidence indicates a high potential for widespread or noticeable weather impacts. A Regional Weather Notice may be issued to provide detailed regional commentary and timeline context. |
Independent Status: South Island Meteorological Agency (SIMA) is an independent private entity. We are completely separate from MetService (Meteorological Service of New Zealand Limited) and the National Emergency Management Agency (Civil Defence). SIMA does not issue official government safety warnings or civil emergency directives.
Informational Purposes Only: All content, maps, graphics, and regional forecasts provided by SIMA are intended solely for general public information. While we strive for meteorological accuracy, atmospheric modelling is inherently uncertain and subject to rapid change.
Liability Release: SIMA assumes no legal liability or responsibility for any loss, damage, disruption, or injury resulting directly or indirectly from reliance on our forecasts or publications. Always consult MetService for official emergency watches and warnings, and follow instructions from local Civil Defence authorities during extreme events.
Copyright & Attribution: All original forecast graphics, maps, and commentary generated by SIMA remain the property of South Island Meteorological Agency unless otherwise noted.
