Daily Data for Each Month of 1999

1999- Warm, quite sunny, above average convective activity

1999 was another very warm year- the third in succession, the mean just sneaking above 10.0C for the first time.  With thunder heard on 13 days it was the most thundery year since I began recording.  Like most recent years, snow and frost were well below average, but the frequency of hail was slightly above average.  There were no days of 25C or above during the summer quarter, then September had three such days.

Winter 1998/99 was warm and dominated by westerly winds, but occasional northerly outbreaks brought snow with them, and as a result the frequency of snow was close to the 1971-2000 average.  Most of these snowfalls were coastal, and inland parts of the region had much below average snow.  Spring 1999 was warm and wet (but not quite as wet as 1998) and the summer was modestly warm with close to average sunshine and rainfall.  The summer, however, was notable for a relative lack of North Sea murk, and also for the way it continued well into September.  Autumn 1999 was another warm one- until 2006 it was the warmest recorded- with a memorable summer-like September which was actually warmer than August had been.  December 1999, in contrast to most of the rest of the year, was cold, and it was also exceptionally sunny.

January 1999- Warm, changeable, quite sunny, with a wintry spell in the second week

January 1999 began with a very warm first week, with an emphasis on bright showery weather.  There was a weak northerly outbreak in the second week, but it was cold enough for snow, with some hail and sleet showers late on the 8th which gave a dusting, and a few snow flurries on the 9th.  Moderate snow accumulated overnight 10th/11th, and although the wind picked up off the North Sea on the 11th bringing a sleety shower, the snow cover lasted until late on the 12th.  From then until the 27th, south-westerly winds prevailed and brought a large number of sunshine-and-showers days, but the last four days were dry and cloudy.  Overall, it was the warmest January since 1993.

February 1999- Alternating warm and cold spells, very sunny at times

The 1st was a sunny day, but it was cloudy from the 2nd to 4th.  It turned sunny again on the 5th, and then much colder weather swept down from the north.  Heavy snow showers fell overnight 8th/9th, and there were a few snow showers also on the early morning of the 10th.  The 9th and 10th had sunshine all day, resulting in a partial thaw of the snow cover.  It turned cloudy and mild in the second week, followed by another northerly on the 16th/17th with some wet snow during the intervening night.  Heavy showers with hail, and eventually sleet, fell on the 21st.  The last week was very sunny, dry until the 25th, with some showers on the 26th, 27th and 28th.

March 1999- Exceptionally wet first third, then warm and changeable

The theme of modest but consistent monthly warmth continued.  It started with a low pressure system stalling out in the North Sea and the first third was exceptionally dull and wet.  Rain turned sleety at times on the 4th and 5th.  The middle third of the month was mostly warm and sunny, with a notably high maximum of 16.4C on the 17th.  The last week was changeable with temperatures mostly near or above normal.  There was a showery day with hail on the 26th, followed by the month's only air frost on the 28th.  The month ended very warm with southerly winds.  Overall, this was the wettest March recorded with more than twice the normal rainfall, but sunshine was close to normal.

April 1999- Generally warm, showery and quite sunny, but with a potent Arctic outbreak midmonth

The month began warm and sunny for the most part, but low cloud from the North Sea was an occasional nuisance.  It turned showery early in the second week, then a northerly outbreak commenced on the 12th with a dramatic hailstorm whitening the ground.  The 13th had outbreaks of snow, and the maximum of just 4.5C was the lowest recorded for April- as was the subsequent night's minimum, -3.8C.  Snow showers fell on the 14th and early on the 15th also, then it became less cold with sunshine and showers every day, except for a one-off dull wet day on the 20th.  It turned much warmer from the 21st, remaining showery for a time, then cloud and drizzle arrived, then the last few days were sunny and dry.

May 1999- Very warm, cloudy, some dramatic convective storms in the second week

May 1999 began settled, dry and cloudy.  It turned cloudy and wet between the 6th and 9th, then a very dramatic spell of convective weather arrived between the 10th and 13th, with frequent hail and thunder and a fair amount of sunshine in between the showers.  TV forecasters lauded an “improvement” in the weather as it turned mainly dull and drizzly for a week afterwards.  The last week was mainly changeable and quite warm at times with mostly westerly winds, and a brief southerly incursion brought some thunderstorms early on the 28th.  Overall, this was about as warm as the exceptional May 1998 and the warmth was consistent rather than outstanding.

June 1999- Cool cloudy first half, warm sunny second half

June began with a dry sunny day, then a dull wet day followed with a little thunder.  The rest of the first week was mostly cool and cloudy with winds swinging around to the north, but there was a climatic day on the 5th with sunshine and showers and some large hail in the early afternoon.  Cloudy drizzly weather persisted until the 12th, then around midmonth it turned sunny and warm.  Two showery days followed on the 20th and 21st, then the morning of the 22nd had a small tornado just to the west, then the showers cleared by lunchtime.  The last week was often sunny and warm, with some heavy showers and a distant rumble of thunder on the 28th.  Overall this was a statistically near average June.

July 1999- Warm, sunny and dry

It began warm and humid, with distant thunder on the 2nd, then turned bright and showery on the 4th.  Thunder was heard from a cumulonimbus to the south on the 5th, but no showers came overhead.  There was a big cloudburst late on the 6th.  Dry, sunny weather persisted during the following week, right through until midmonth.  The third week was dominated by sunshine and showers and westerly winds, and a frontal system featured a gush of hailstones on the 19th.  The 21st and 22nd were cloudy, but it became mainly sunny again towards the end of the month- except for the 30th when sea fog rolled in.  Unusually for a warm sunny dry month, the positive temperature anomaly was as large by night as by day.

August 1999- Cloudy humid first third, often showery around midmonth, dull wet 18th-20th, cool sunny last third

August began with three warm dry sunny days, but it turned cloudy and humid from the 4th-6th, and then the 7th-9th were dull, cold and drizzly.  The weather became warm and sunny later in the second week, and then the 14th-17th were dominated by sunshine and showers, with thunder on the 17th.  The 18th was extremely cold and wet, the rain eased slowly on the 20th, and there was an exceptionally cold night on the 21st/22nd.   A sunny, cool spell followed.  There was a thunderstorm late on the 25th followed by two showery days.  Moderately warm, humid weather ended the month.  Overall, this was the wettest August since before 1993 but it has been exceeded a few times since.  It was also rather cool- the coolest since 1994.

September 1999- Exceptionally warm and sunny, frequent convective storms in the second half

 The first half of September contained some of the hottest and sunniest weather of the entire year.  There was an exceptionally warm night on the 1st/2nd and the temperature nudged 27C during the day.  The 6th was almost as warm, and it got up to 24C on the 11th.  There was an abrupt change to unsettled conditions in the second half, and persistent southerly winds brought a continuation of above-average temperatures together with showers and occasional thunder, but also some generous sunny periods.  The thunderstorms on the evenings of the 22nd and 26th were quite severe.  The 20th and 27th were the only dull wet days.  September was both warmer and sunnier than August had been.

October 1999- Slightly warmer, drier and sunnier than average, not a memorable month

The first week began with four showery days, and as the northerly flow slackened, two notably cold nights followed, with the 6th coming extremely close to recording an air frost.  It was warm but cloudy around the 10th.  A few days of dry sunny weather followed, then easterly winds persisted until the 22nd bringing warm nights and a lot of cloud.  The 21st-24th were very wet.  The last week had changeable south-westerlies but it was often quite sunny.

November 1999- Warm and cloudy, a not-very-potent northerly outbreak in the third week

The first week was warm and changeable with westerly winds.  The 4th was very warm with 16C, then the 5th was a very wet day.  A large anticyclone reigned from the 8th, which brought dry sunny weather initially but then a prolonged spell of anticyclonic gloom set in.  It turned brighter and colder on the 16th, heralding the start of a northerly outbreak.  It was quite a feeble northerly, with showers on the 18th and 19th falling mainly as rain and hail, except for a heavy lunchtime shower on the 18th that turned briefly to snow.  However, it was notable for squally winds and intense downpours.  Warm, changeable south-westerlies returned for the last week. 

December 1999- Quite cold, changeable, exceptionally sunny

December began with a very warm day but it soon turned colder with north-westerlies and a couple of sleet showers on the 4th.  A warm spell with sunshine and blustery showers followed, followed in turn by a gradual drop in temperature.  There was a sharp frost early on the 14th, then a strong north-easterly brought a barrage of hail and sleet showers, and even some thunder on late evening.  Early on the 15th, there was snow cover just 1 mile further inland but Cleadon only had a smattering of hail cover.  Light snow fell frequently on the 18th but failed to produce any meaningful accumulations, and light snow flurries early on the 19th produced the same result.  The night of the 19th/20th was notably cold..  After a gale on Christmas Eve, a showery Christmas Day contained a very unexpected flurry of wet snow.  Bright frosty weather followed.  Sunshine may well have approached twice the normal this month- the lack of dull days was remarkable.