September 2023 Report – Temperature and Humidity in York

This is the next instalment of our hygrometer reports which we’re continuing to produce which, using our own bespoke remote monitoring equipment, we track a full month of weather focusing on the relative humidity and temperature in York, this time covering September 2023.

We detail, examine and compare indoor and outdoor hygrometer readings throughout this month in which summer ends and autumn starts. We analyse highlights, averages, highs and lows seen across the month. This is a month that people commonly put their heating on for the colder weather and may spot their boiler losing pressure after not being used for some time.

Historical reports we have produced are in a separate hygrometer section of our blog – you can see last month’s Temperature and Humidity in York – August 2023 report

Let’s start with the headline figures and a summary:

• September 2023 was cooler in York, with average outdoor temperature at 16.9°C
• This was more so later in the month, with average temperatures closer to 15°C
• The maximum outdoor temperature in York was 27.5°C and the minimum was 8.4°C
• This means an outdoor range (between the top and bottom) of 19.1°C
• The average indoor temperature was higher at 21.0°C
• The maximum indoor temperature in York was 25.7°C and the minimum was 18.1°C
• This gives an indoor range of just 7.6°C which is much narrower (as usual)

Hygrometer Temperature Trends – September 2023

The chart above shows the full, breakdown of trended readings across the whole month, from which the September 2023 highs, lows, range and averages were calculated. It demonstrated daily cycles of temperature variances with (as you would anticipate) highs during the day and lows during the night. As we covered earlier, from around the 12th September temperatures dropped.

On this graph, you can clearly see the outdoor temperature peak in York on 9th September in the afternoon. Equally, the lowest temperature late in the month on the morning of 22nd September.

You can see the indoor temperatures were on average slightly higher, especially when the weather got colder and that the trends of warmer and colder days in York the month generally follows for indoors and outdoors.

Humidity in York – September 2023

Here are the headlines from the humidity readings from York in September 2023:

• September 2023 had an average outdoor relative humidity of 77.6%
• This is noticeably higher than August, as we get into colder months
• The highest outdoor humidity in York was 94% and the minimum was 41°C
• This means an outdoor range (between the top and bottom) of 53%
• As seen before, lower humidity happened when temperatures were higher
• As we have covered previously, warm air has a higher capacity to hold moisture
• The average indoor relative humidity was lower at 64.0%
• The maximum indoor humidity in York was 75% and the minimum was 52%
• This gives an indoor differential range of just 23% which is less than outdoor

On the topic of temperatures and humidity, see our guide explaining what is condensation.

Hygrometer Humidity Trends – September 2023

The chart above shows the detailed data set from which September 2023 highs, lows, range and averages were derived. The outdoor relative humidity is higher in general in part because temperatures are lower but equally because it is more exposed to rain, which can additionally increase humidity levels also.

We reference this in some more detail in our interesting article explaining causes of mould on walls.

Temperature Ranges in York – September 2023

Above, we mentioned the comparison between indoor vs outdoor temperature ranges in September 2023 and the charts above help to demonstrate this. As you will notice, the outdoor (top chart) readings were in a much wider range than the equivalent indoor (bottom chart) readings, this is to be expected in a controlled environment.

The more detailed range graph below helps to explain this further:

As you can see, the indoor temperature readings taken from the hygrometer readings for September 2023 are more closely grouped with c.65% of the readings being at 18°C to 20°C (rounded to the nearest degree). In contrast, the outdoor readings are far more widely spread.

This is repeated similarly with the relative humidity readings:

Temperature and Humidity by Time of Day – September 2023

The final set of useful data for September ’23 compares at how different times of day affect indoor and outdoor readings taken by the hygrometer data loggers. The four familiar groups are:

• Morning – 6am to Noon
• Afternoon – Noon to 6pm
• Evening – 6pm to Midnight
• Night – Midnight to 6am

As you would predict, usually the afternoon was the warmer part of the day in York during September 2023 with the night being the coolest, morning and evening were fairly similar, with evening readings being fractionally warmer on average vs the morning. This was the inverse of relative humidity for the reasons covered earlier.

We can assist you with the following:

• Damage Management in York
• Damp and Mould Problems in York
• Flood Damage in York
• Water Damage Services in York
• Leak Detection in York

Temperature and Humidity Measurement – Other Useful Information

Here are a few other posts related to this particular subject that you may find useful to view:

• Bathroom Leaking – Most Likely Places
• Leak in Floor or Underground
• Plumbing Leak – Finding it
• Washing Machine Leaking Underneath
• Leak Under Sink in Kitchen

If you have a water leak contact and are interested in our trace and access services in Yorkshire our local friendly and experienced team for help.

At Rainbow Restoration – York & Yorkshire Coast we are experts in Leak Detection, including business water leaks, so if you need help finding a water leak or getting your property back to normal after a water damage or a flood, get in touch with our friendly local team who will be happy to help you with this. We are based in York and help with leak detection in York.

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