Weather-normalized values aren't showing, your data coverage drops when you enable weather normalization, or your degree days look wrong? This article walks you through the most common issues — including why you can have 100% data coverage without weather normalization but not with it.

Why is data coverage lower with weather normalization than without?

This is the most common question and has a straightforward explanation. A weather-normalized series depends on four data streams — if any one of them is missing for a given period, there is no normalized value for that period:

1. Energy values from the meter (your regular meter readings)
2. Degree days for the property's location (fetched from Degreedays.net or SMHI)
3. Normal year data for the location (the reference period used for comparison)
4. Hot water proportion / base load (if you have configured this on the meter)

Without weather normalization, coverage is calculated only on the energy series, which you may have fully. With normalization enabled, degree day data directly affects coverage. If Degreedays or SMHI is missing values for a given month or location — or if degree days have not yet been fetched — coverage drops for that period.

Expected behavior: it is normal for coverage to be somewhat lower with weather normalization, especially for recently added locations or current months where degree days have not yet been delivered by the source.

Troubleshooting checklist

Work through these steps in order:

1. Verify that zip code and country are filled in on the property — without these, the system cannot fetch degree days. Go to Edit on the property level and check these fields.
2. Verify the meter's usage type — degree days are only fetched automatically for meters with a usage type set to Heat or Cooling.
3. Verify that the meter has energy readings — the degree day calculation requires energy values to normalize against.
4. Check data coverage for the normalized series — go to the Data Coverage & Alarms report → Report settings → Calculations → Weather normalization. Here you can see coverage for the combined series (energy + degree days). Note that you must have Heat (or Cooling) enabled in report settings for this series to appear.
5. Check that you are at the right level in the structure — weather-normalized reports should be run at property or meter level, not at group level. At group level, the system averages degree day locations, which gives misleading results when properties are in different cities.
6. Check hot water / base load settings — if you have configured a hot water proportion, verify it is entered correctly under Meter settings → Calculations.
7. Verify the location has sufficient history on Degreedays — locations must have data from at least 2005. Search for your location on degreedays.net and hover to see the available period.

Degree days have never been fetched — what should I do?

For cooling meters, degree days are not activated automatically. Contact your Customer Success Manager or Mestro support to enable this.

For SMHI degree days, the customer must order a subscription directly from SMHI. Once SMHI confirms the subscription, contact support to activate it in Mestro.

Want to change your degree day location? Contact support with the desired location — changes are usually possible if the location has data from 2005 or earlier.

Degree days look incorrect

Degree days are delivered by external sources (Degreedays.net or SMHI) and it may take time after publication before they are loaded into Mestro. The timing depends on when the source system delivers data and the size of the processing queue. Mestro processes all incoming data as quickly as possible.

Contact support@mestro.com or your Customer Success Manager if you suspect degree day data is incorrect after working through the checklist above.