April 2003

1st to 3rd An active front swept south-east bringing sunny spells and blustery thundery showers on the 1st, thereafter sunny periods and warmer, with mostly light scattered showers.

4th to 9th Mainly dry as an anticyclone over the UK migrated north-east to Scandinavia, later extending a tongue south-westwards towards the region. It became sunny and warm or very warm inland during the 4th and 5th but colder after with overnight frost, though still mostly sunny. The 9th saw some patchy sleet in places.

10th to 12th Cold especially at first with widespread overnight frost, a band of light sleet and snow affected southern England during the 10th. At Hawarden near Chester -7.5 °C was recorded. Mostly sunny by the 12th after clearance of early morning mist and fog patches.

13th to 18th Mainly dry, sunny and very warm as the Scandinavian high became the dominant feature of the weather. Some light rain in southern areas on the 14th left dust deposits. Southerly winds brought extremely high temperatures inland, with Wolverhampton reaching 27.3 °C on the 16th. This was the highest April temperature in the UK since 16 April 1949. Records were broken in many places. Some areas had moorland and heather fires, while a stiff easterly breeze from the 17th fanned outbreaks in west Surrey and Hants during the 18th.

19th to 23rd More changeable as a shallow low from the south brought cloud and lower temperatures. Forest and moorland fires affected parts of Wales, Cornwall and Dorset on 20th. Thundery showers broke out early in the south-east on the 21st, giving a second dust fall in places, thundery rain also affected Cumbria and north-west England. Dry sunny and warm weather returned on the 22nd and 23rd, however rain moved into the south-west later.

24th to 30th Mostly unsettled and sometimes windy as low-pressure systems from the North Atlantic tracked close by or over the UK. Bands of rain and showers, often heavy with thunder, affected many parts especially in the west and north-west of the region. There was rain on the 25th, with a few thundery showers in the south on the 26th, and this was followed by widespread wind and heavy rain later on the 27th and into the 28th. There were locally heavy thundery showers in the north on the 29th, while more thundery outbreaks affected western and southern areas during the 30th.

The remarkably dry, warm and sunny weather experienced for much of March continued until the last week of April, when there was a complete change to a cyclonic weather type with rain and showers.

A brief break in the long fine spell occurred at the beginning of the month, when a strong, cold and showery north-westerly airstream blew across Scotland. However, high pressure soon built from the west, with warm air circulating around it. The 3rd to the 5th were warm with sunny periods in the south, although it was rather cloudy in the north.

From the 6th to the 10th the high pressure was centred to the east, and most places were dry with a good deal of sunshine. Colder air advanced from the east, with the temperature falling to -6 °C at Aboyne on the 10th.

The weather became less settled from the 11th to the 13th as pressure fell and sunshine was interrupted by showers in a few places.

A heat wave occurred from the 15th to the 18th as the anticyclone over Scandinavia returned westward and warm southerly winds blew across Scotland. It was sunny everywhere, and the temperature reached 26.9 °C at Lochcarron on the 17th. This set a new record April temperature for Scotland, beating the previous highest of 26.7 °C at Dollar in April 1870.

Falling pressure on the 19th and 20th brought strengthening easterly winds and lower temperatures, but the weather remained dry and sunny. A trough crossing Scotland from the south brought rain and showers on the 21st and 22nd, but fair weather returned on the 23rd and 24th.

The final six days of April were cyclonic, with bands of rain or showers affecting all parts.

Conditions proved rather warm throughout April, with both day and night-time temperatures recording values above average. This was a sunny month, with total sunshine durations greater than expected for time of year, indeed many areas recorded up to 27 days with measurable sunshine. April was a dry month with most areas recording below average values. With the exception of the 13th, most areas recorded little or no measurable rainfall between the 3rd and 20th of the month.

1st to 3rd Conditions at the start of April were unsettled, as a frontal weather system tracked quickly across the province. This brought moderate to heavy showers on the 1st, which were at times wintry in nature. Thunder and hail also accompanied some of the showers. Mainly light showers followed into the 2nd and 3rd, but it was generally warm over these two days, with good spells of sunshine. Winds were initially fresh to strong in strength and blowing from a mainly west to north-westerly direction but they eased to become gentle to moderate by the 3rd.

4th to 12th An elongated area of high pressure extended over the British Isles during much of the period, giving a period of mostly dry and sunny weather to all areas. However the 12th was a dull day everywhere as cloudier conditions developed. Temperatures were above average by day, but clearing skies by night allowed values to fall below normal giving rise to air frosts on the 9th, 11th and more locally on the 10th. Widespread ground frosts were recorded between the 5th and 11th, with many areas recording moderate to severe frosts on the 11th. Early morning fog affected many regions on the 4th, while persistent mist was recorded on the 7th and again on the 8th, but it was patchier in nature.

13th to 20th Once again a predominantly high pressure weather system dominated over this time and with the exception of the 13th, very dry, very sunny and very warm conditions for April prevailed. A frontal system tracked across the province on the 13th and brought dull, cloudy conditions with mainly light rain to many areas. However more persistent, moderate rain was recorded in the extreme south-east region of Co Down on this day. During the period between the 15th and 20th many areas recorded over 10 hours of sunshine on each of these days alone. While the 16th and 17th were very warm days everywhere with day-time temperatures recording values around 10 °C above the average for this time of year. Indeed some areas broke their highest maximum temperature record for April on the 17th. The highest recorded daytime temperature of 22.8 °C was recorded in the north at Portrush on the 17th.

21st to 23rd More changeable weather developed as low pressure moved up from the south. This brought cooler and duller weather, with moderate to heavy rain and/or showers, with some heavier outbreaks affecting many areas on the 21st. However drier, sunnier and warmer weather once again returned across the province for a short time on the 22nd and 23rd.

24th to 30th A succession of low pressure weather systems tracked quickly north-eastwards bringing more unsettled weather throughout Northern Ireland. During this period temperatures remained above normal in a southerly airflow. Moderate and at times heavy rain and showers, interspersed with good spells of sunshine were recorded on each of these days. Thunder and hail occurred in many areas on the 30th. No sunshine was recorded anywhere on the 28th.