Forecast Model Options Follow

WeatherFlow-Tempest Forecast Models 

WeatherFlow-Tempest Lifestyle apps (iKitesurf, iWindsurf, SailFlow, Fishweather, WindAlert) deliver accurate forecasts globally. We utilize weather prediction models from NOAA and other government agencies (e.g EMWF) and also run high resolution models ourselves in many key areas, often enhanced with machine learning and other forms of AI.

Generally, we try to show by default the model that has proven most accurate over time in a given region, while reflecting the subscription status of a user.   Some models are only available to Plus and Pro subscribers.  

We make available several model choices since different forecast models often emphasize different atmospheric processes and come with unique biases. By comparing several models, you capture a range of possible outcomes and may better gauge uncertainties in your area.  While generally the default model will be most helpful on average, if you embrace being a power user you may find that comparing models best meets your needs—whether you’re tracking local winds for today’s time on the water or large-scale weather patterns for a long-term outlook.
 

iKitesurf WRF 26 - iKitesurf WRF AI Enhanced High-resolution Weather Forecast Model v2026

The iK WRF 26  is our constantly improving proprietary model foundationally built on the Weather Research and Forecasting (WRF; pronounced “wharf”) state of the art mesoscale numerical weather prediction system.  WRF can be run across multiple scales and we now enable our version at a minimum of 3km. In most places across the continental US and Europe (coming July 2026) it is available at 1km resolution.  Our system updates every hour in many locations and every four hours at the least

Our current version of this model offering (v26) combines the best of many of our past efforts. It includes new leading edge IP and represents a significant breakthrough in our product offering.  We expect to continue to release improvements in the current and future years and welcome all feedback.  The foundational elements of our WRF 1km model have long been a valuable resource for our customers and forecasters. It takes into account the effects of terrain, bodies of water, observation data and other factors that contribute to the complexity and nuances of local weather conditions more than any other model. We will continue to perfect our enhanced WRF model through substantial investment in this resource.

Note to CA subscribers -   iK WRF 26 represents a milestone in an effort that was heightened over the past two years.  Some of you have previously discovered and utilized our WRF (beta) model which offered the key attributes of WRF 26 but often failed to run consistently.  The reliability issues should now be behind us and best of our modeling expertise presented in new model runs and the “beta” tag is in the past.
 

Regional NWP Models

HRRR - High Resolution Rapid Refresh

The HRRR is National Oceanic and Atmospheric Administration (NOAA) & National Centers for Environmental Prediction (NCEP) operational weather prediction system comprised of a numerical forecast model and an analysis/assimilation system to initialize the model. It is run with 3 km resolution over CONUS every hour, and the high temporal and spatial resolution often yields the best available output for TRRM in certain locations.

ARW 5km - Hawaii Model
This model run from UCAR incorporates codes from several different NWP models in an attempt to get better accuracy in Hawaii and Alaska than is attainable with the Global Models. The 5km resolution enables the model to incorporate the intricacies of islands and varying topography.

NAM - North American Mesoscale Model

The North American Mesoscale Forecast System (NAM) is one of the National Centers For Environmental Prediction’s (NCEP) major models for producing weather forecasts. Based on WRF code, NAM runs 4 times per day and generates multiple grids of weather forecasts over the North American continent at horizontal resolution ranging from 3km to 12km depending on location.  It has proven to be quite accurate over the first 48 hours in areas where spatial resolution is high, and therefore may be selected as the base model for TRRM in some circumstances.

RRFS - Rapid Refresh Forecast System

The Rapid Refresh Forecast System will be replacing the NAM in September 2026. The RRFS is NOAA’s next-generation, rapidly updating, high-resolution weather model. It is run with 3km resolution over CONUS every hour. 

BLEND - Blend of Models

This model combines short and long-range NWP forecast model output for a complete forecast table that extends for 14 days. The BLEND uses the best available high-resolution, hourly updating NWP computer model when available  for forecasting the next 48 hours and blends that output with coarser resolution data for an extended forecast.  With a single data set, BLEND allows you to view both short and long term forecasts, while bringing the accuracy only available in short-term NWP model output.

Global NWP Models

Global NWP Models are characterized by lower spatial resolution but as the name implies these models provide forecast data for the entire globe.   In remote areas this is often the only data available.  Global NWP models are also integral in the initialization of higher resolution models over targeted geographic areas.

ECMWF -  European Centre for Medium-Range Weather Forecasts primary global model

ECMWF’s global forecasts are generally recognised as the most skilful of the global models in predicting weather phenomena over the medium term. 

GFS - Global Forecast System
The GFS is run four times a day by NOAA and produces forecasts up to 16 days in advance.  It is run at roughly 50km resolution.  However, the spatial and temporal resolution is reduced as the model is further out in time.  It produces a forecast for every 3rd hour for the first 180 hours. 
 

CMC - Environment Canada Global Model
This is another model which will give you a forecast for all points on the globe. The resolution is approximately 100km resolution and runs out 138 hours. 

TRRM - Tempest Real-time Refresh Model (not currently offered to consumer subscribers)

The Tempest Real-time Refresh Model (TRRM), WeatherFlow-Tempest’s first premium weather forecasting product.  The TRRM 25 model has largely been supplanted by iK WRF 26 as our most accurate wind prediction model over a time scale of 1 hour to 36 hours.  TRRM 26/27 is currently undergoing a redesign process which will enhanc it’s unique path combining the best-available numerical weather prediction models (NWP) for a given point with well-tuned/trained AI modeling. The TRRM model leverages high-density weather station datasets curated from the WF-ProNet, Tempest networks and other weather station networks. This rapidly growing set of observation data is a powerful tool for training the AI model for areas rich with this data.