The Forecast is based on the Barometric Pressure reading, among other factors. In order for the Barometric Pressure reading and the Forecast features to be accurate, the display requires the completion of a Learning Mode.

The Learning Mode algorithm begins with global average pressure (29.92 inHg). The weather station then takes 4,000 readings at 12-minute increments to calculate a running average and compute the barometric pressure for your exact location.

The pressure accuracy of AcuRite self-calibrating forecasters increases with each new reading over the Learning Mode time period. After 14 days, the Learning Mode icon disappears from the weather station screen. At this point, the self-calibrated pressure is reasonably accurate (although the algorithm continues to run; 4,000 readings = 33.33 days).

The Forecast icon predicts conditions for the next 12 to 24 hours, not current conditions.

If the Barometric Pressure or Forecast is inaccurate:

1. Please allow up to 33 days for the pressure to calibrate itself to your location.
2. If the display has been powered on for 33 days and has not been reset within the learning mode, perform a factory reset of the display. Most displays will have a reset button located in the battery compartment. If the display does not include the reset button feature, remove the batteries and/or power adapter for 2 minutes to reset the display. 
3. Please allow the display to complete its full 33-day Learning Mode for a second time after a reset before assessing the accuracy of the Barometric Pressure or Forecast.

If your unit continues to read inaccurately, please consider if you may live in a microclimate. Some examples of a microclimate are being “cooler by the lake”, in a deep shaded valley, close to the ocean or lake, on the side or top of a mountain, or in places that have daily winds that might switch directions from day to night. If you live in such a unique climate, the changes in temperature and pressure can cause the forecast to read incorrectly. This only affects a small number of our users.

*Most AcuRite products can measure Barometric Pressure down to 17.7 inHG. You may see inaccurate readings at higher altitudes or if the Barometric Pressure is below this measurement.