Your Calendar Pollen Forecast
The ITV Weather Pollen service has now ended and will return in 2025.
For a daily pollen forecast, check the Met Office website.
Local Pollen information for the Calendar region:
From the end of May to the beginning of August, Yorkshire experiences a relatively shorter grass pollen season compared to southern regions of the UK. However, grass pollen counts can still be high in inland lowland areas, leading to fairly severe seasons. Lincolnshire and Derbyshire, being further south, have higher pollen counts in general through the grass pollen season.
Lower Pollen Count Areas
Upland Areas: Regions such as the Yorkshire Moors typically have low grass pollen counts due to the types of vegetation present, which produce less grass pollen.
Coastal Areas: While coastal areas generally have lower pollen counts, the prevailing westerly winds can bring pollen from inland areas, making the pollen counts higher compared to coastal regions of northwest England.
High Pollen Count Areas
Lowland Areas Inland: All lowland areas, particularly those with uncut grass verges, can experience high pollen counts.
Urban Areas: Large built-up areas like Leeds, Sheffield or Bradford often have higher pollution levels, which can exacerbate hay fever symptoms.
What is pollen?
Pollen is a very fine powder produced by the male parts of trees, flowers, grasses and weeds to fertilise other plants of the same species. Many people have an adverse immune response when they breathe in pollen.
The immune system normally defends the body against harmful invaders, such as viruses and bacteria, to ward off illnesses.
Some people's immune system mistakenly identifies harmless pollen as a threat to the body and tries to fight it by releasing a chemical. We call this an allergic reaction, which can lead to a number of irritating symptoms such as:
sneezing
stuffy nose
watery eyes
The Pollen Count
A pollen count is generated by measuring the number of pollen grains in a given volume of air, using a pollen trap. This information is collected by the Met Office and added to weather forecasts to provide the pollen forecast.
What effect does time of day and weather have on pollen count?
The pollen count changes hour by hour but there are two distinct times of the day when pollen is considered at its peak.
Most pollen is released in the morning. As the air warms, pollen is carried higher in the atmosphere as the warm air warm rises.
In the evening when the air is cooling, pollen sinks back closer to the surface, so you may notice if you are in your garden in the evening your hay fever may get worse.
How does different weather affect pollen?
Sunny days favour higher pollen counts. On a cloudy day, pollen builds up only to be released on the next sunny day.
Morning rain causes the pollen count to remain lower through the day as wet conditions are not optimum for pollen to be released.
On the other hand, if the onset of rain is later in the day, pollen can hang around for a good portion of the day as the rain droplets keep the dispersed pollen closer to the surface.
Windy weather tends to quickly disperse pollen and make for a more comfortable day for hay fever sufferers.
Interestingly there is research looking at the effects of thunderstorms and the impact they have on people who have respiratory issues in the immediate few hours after a thunderstorm.
Scientists are looking at how pollen may burst open in changes in pressure along with updrafts and downdrafts produced by thunderstorms. This may be partially responsible for a local spike in respiratory problems observed by hospitals and doctors in the vicinity of a storm.
How is pollen different in rural and urban areas?
In rural areas, the evening peak tends to occur between 6pm and 9pm.
Meanwhile in urban areas, where the air stays warmer for longer, the pollen descends later and levels tend to peak between 9pm and midnight or even later, which is why you may wake up sneezing in the night.
Is climate change impacting pollen?
Climate change is leading to more frequent intense weather events due to man made activity, as a result native plants will have to adapt.
Pollen is forecast to become more extreme and there is the potential for foreign species to take hold which are more allergenic and this could become a problem in the future.