Category Archives: Monthly Review

May 2018: warmth and thunderstorms

This May will probably be most remembered for the number of thunderstorms affecting the area. I recorded an unprecedented (in my memory) four consecutive days of thunderstorms.

convection
Convective clouds build over Wanstead Flats

It was also warm with a couple of days making the top 10 of hottest days since 1959. The mean temperature finished 15.1C, 2C warmer than average, the warmest May for seven years and the 8th= warmest since 1797.

Rainfall at 65.5mm was 128 per cent of average and slightly drier than last year.

Some 244hrs of sunshine were recorded, 134 per cent of average, making it the sunniest May for 7 years, and the 11th sunniest since 1881.

Spring finished with a mean temp of 11C, 0.8C above average, 1C cooler than last year. Rainfall at 181.9mm, was 135 per cent of average, making it the wettest spring for 10 years. Sunshine of only 411.2 hours made it the dullest spring since 2006.

The warmest day occurred on the 7th with 28.1C.

The wettest day occurred on the 29th with 29.8mm falling during a prolonged thunderstorm.

Air frosts: 0, Ground frosts: 0

This summer in east London is looking average with little to write home about weatherwise.

Summary for May 2018

Temperature (°C):
Mean (1 minute)  14.7
Mean (min+max)   15.1
Mean Minimum     9.0
Mean Maximum     21.1
Minimum          1.8 day 02
Maximum          28.1 day 07
Highest Minimum  15.7 day 31
Lowest Maximum   14.1 day 02
Air frosts       0
Rainfall (mm):
Total for month  65.5
Wettest day      29.8 day 29
High rain rate   60.4 day 28
Rain days        9
Dry days         22
Wind (mph):
Highest Gust     20.6 day 02
Average Speed    2.4
Wind Run         1808.0 miles
Gale days        0
Pressure (mb):
Maximum          1027.4 day 16
Minimum          1001.5 day 02
Days with snow falling         0
Days with snow lying at 0900   0

 

 

 

 

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April 2018: four seasons in one month

I normally headline these monthly reviews by referring to the most notable weather but this April, often a fairly non-descript mid-spring affair, offered pretty much every type of weather. bluebells

The mean temperature finished 11.7C, 1.9C above average and the warmest for four years.

Rainfall was 55mm, 129 per cent of average and the wettest for 6 years.

Sunshine was just 110 hours, the dullest for 40 years and the 16th dullest since 1881.

Hidden in the positive monthly anomaly was the warmest April day in a local record going back to 1959: 29.1C on the 19th – a figure that represents a positive anomaly of 14.9C and occurring at the start of the warmest April heatwave since 2011. It was remarkable that such an anomaly happened so close to a record negative anomaly the previous month.

Yet, just over a week later, temperatures lurched cold again with one of coldest last days of April on record. Though the 24hr record wasn’t broken the noon-6pm record going back 60 years was beaten.

The wettest day occurred on the 9th with 10mm falling.

Air frosts: 0, Ground frosts: 1

sunset 22nd

18th warmest

29.1

rainapril30
April 30th provided a timely reminder after the heatwave to ne’er cast a clout till May is out. A low pressure system in the North Sea brought a thoroughly miserable day though even more rain fell across the Channel.
april30
It was a month with some amazing sunsets. This one, on April 30th, happened just as the sky cleared before dusk

 

March 2018: cold, some snow and very dull

Though March is usually, meteorologically speaking, the first month of spring this year it felt more like an extension of winter.
Screen Shot 2018-04-01 at 11.09.47
This graph shows that the two visits from the “Beast From The East” were only enough to momentarily dent the average.

The mean temperature for March 2018 finished 6.3C, that’s 1.4C below the 1981-2010 average, the coldest for five years but still nearly 3C warmer than the exceptional March of 2013.

Some 61.5mm of precipitation fell, that’s 151 per cent% of average and the wettest for 10 years, pipping the wet March of 2016 by just 1.2mm. The 38th= wettest March since 1797.

 

Screen Shot 2018-04-01 at 11.17.13
The wet end to the month is shown on this graph.
Perhaps most notable in this region was the lack of sunshine. There was just 59.1hrs recorded, that’s just 54 per cent of the 1981-2010 average. The dullest March since 1984 and, more notably, the 5th dullest March back to 1881!
Though there were no notable night frosts, the coldest night fell to just -3.8C, the cold pattern was enough to create three new entries in the top 10 of coldest March days in Wanstead and further afield in the capital.
With 6 more days of ‘snow lying at 9am’ winter 2017-18, the snowfall season stretches from October to May, was boosted up to 20th place on my snow index.
Summary for March 2018
Temperature (°C):
Mean (1 minute)  6.1
Mean (min+max)   6.3
Mean Minimum     3.0
Mean Maximum     9.6
Minimum          -3.8 day 01
Maximum          15.3 day 27
Highest Minimum  8.0 day 15
Lowest Maximum   0.5 day 01
Air frosts       5
Rainfall (mm):
Total for month  61.5
Wettest day      9.0 day 30
High rain rate   12.1 day 12
Rain days        20
Dry days         11
Wind (mph):
Highest Gust     24.4 day 08
Average Speed    3.2
Wind Run         2411.5 miles
Gale days        0
Pressure (mb):
Maximum          1032.3 day 20
Minimum          983.3 day 11
Days with snow falling         4
Days with snow lying at 0900   6
Total hours of sunshine        59.1
snow mar 1
19th march snowmar 3 tree eng thawmar 3 thawmar 2 snowmar 2 roadsmar 1 rada

February 2018: cold, very sunny, snowy end

February 2018 saw the start of the first decent cold spell since 2013 with thick (by modern standards) snow cover, deep cold air and bitter winds.

Screen Shot 2018-03-03 at 15.50.35
February 2018 is marked by the steady downhill temperature trend from the 18th.

It was the coldest February since 1991, the mean temperature of 2.8C was just over 2.5C below average. The month was ‘cold’ though it was the 19th onwards that really dragged the value down.

Precipitation was just below average; just over 34mm is 87% of average.

It was a sunny month, the sunniest February since 2012 and the 12 sunniest in a local record going back to 1881. Some 87.9 hours were recorded, 120% of average. Of that top 12, eight have occurred since 1988! A mix of changes in weather patterns, industry and council action?

Air frosts: 16. Ground frosts: 19. Snow falling: 6 days. Snow lying: 3 days (greatest depth 8cm 28th)

Full stats for February here: http://1drv.ms/1rSfT7Y

settled snow 28th
The 28th dawned sunny with fresh snowfall after an hour long shower at 3am. Within hours more showers moved in.

December 2017: average temps, wet

December 2017 was a wet month. Just over 83mm of rain was recorded, 157 per cent of average, the wettest December since 2012 and the 38th wettest since 1797.

Screen Shot 2018-01-03 at 19.30.21
The snow depth on December 10th reached 5cm at its maximum

The monthly mean finished 5.6C, precisely average and the coolest December for five years.

Some 48 hours of sunshine were recorded, 120 per cent of average, slightly less than last year.

The most notable event was the on December 10th which produced the best snowfall in 5 years

Air frosts: 10. Ground frosts: 14. Snow falling: 2. Snow lying: 1.

January (on the 3rd) is looking like it may produce more snowfall events similar to December though, with models suggesting a build in heights to the north. A look at the output, including GFS and ECM, suggests the UK will be in a battleground between a cold airmass to the east and warm Atlantic air to the west.

It would seem to back up my winter forecast and also the December analogues with nothing warmer than average.

Average: 33%
Rather cold: 17%
Cold: 17%
Very cold: 0%
Severe: 33%

Screen Shot 2018-01-03 at 19.29.51

Full stats for December here:http://1drv.ms/1rSfT7Y

Summary for December 2017
Temperature (°C):
Mean (1 minute)  5.8
Mean (min+max)   5.5
Mean Minimum     2.8
Mean Maximum     8.3
Minimum          -3.7 day 11
Maximum          14.2 day 30
Highest Minimum  9.8 day 21
Lowest Maximum   2.4 day 10
Air frosts       10
Rainfall (mm):
Total for month  83.7
Wettest day      14.6 day 10
High rain rate   12.1 day 31
Rain days        21
Dry days         10
Wind (mph):
Highest Gust     25.1 day 30
Average Speed    3.5
Wind Run         2570.0 miles
Gale days        0
Pressure (mb):
Maximum          1036.4 day 22
Minimum          970.3 day 10
Days with snow falling         3
Days with snow lying at 0900   1
Total hours of sunshine        48.3 (120%)
Screen Shot 2018-01-03 at 19.30.41

November 2017: below average, dry

November 2017 was another dry month. Just over 33mm of rain was recorded, the driest November since 2011 and the 40th driest since 1797.Screen Shot 2017-12-02 at 17.23.28

The monthly mean finished 7.1C, 1C below average and only the fourth cooler than average month this year.

Some 71 hours of sunshine were recorded, 122 per cent of average – the sunniest November since 2007.

Air frosts: 6, Ground frosts: 17, snow falling: 1 (just a few flakes on the 30th, the first November snow in years.)

The start of December looks like it start mainly dry, an anticyclone over the Atlantic that has brought respite from last week’s cold weather will pull away into the continent to be replaced by low pressure. This depression will track across northern England gradually pulling cold, Polar air across the UK on Thursday.

The models go against what has followed dry Novembers in the past – patterns overwhelmingly suggest that December will be average to rather mild and on the dry side. Winter is looking average overall.

Here follows the full weather diary for November…Full stats for the month here:http://1drv.ms/1rSfT7Y

Summary for November 2017
Temperature (°C):
Mean (1 minute)  7.4
Mean (min+max)   7.1
Mean Minimum     3.5
Mean Maximum     10.6
Minimum          -2.7 day 24
Maximum          15.5 day 22
Highest Minimum  12.3 day 21
Lowest Maximum   3.7 day 30
Air frosts       6
Rainfall (mm):
Total for month  33.3
Wettest day      8.5 day 10
High rain rate   12.1 day 22
Rain days        14
Dry days         16
Wind (mph):
Highest Gust     22.1 day 23
Average Speed    2.7
Wind Run         1952.8 miles
Gale days        0
Pressure (mb):
Maximum          1029.6 day 17
Minimum          985.2 day 22
Days with snow falling         1
Days with snow lying at 0900   0
Total hours of sunshine        71.2
Screen Shot 2017-12-02 at 17.24.28

October 2017: warm, very dry and dull

October 2017 was a very dry month. Just 12.6mm of rain were recorded, the driest October since 1995 and the 11th driest since 1797.

The monthly mean finished 13.1C, 1.3C above average and the seventh warmer than average month this year.

Some 81 hours of sunshine were recorded, 76 per cent of average – the 4th duller than average month in a row. Just three months have been sunnier than normal in 2017!

Air frosts: 0, Ground frosts: 2

The first half of November looks like it will be predominantly anticyclonic. Expect lots of calm weather with the usual frost and fog.

Here follows the full weather diary for October…Full stats for the month here:http://1drv.ms/1rSfT7Y

Summary for October 2017
Temperature (°C):
Mean (1 minute)  13.2
Mean (min+max)   13.1
Mean Minimum     9.7
Mean Maximum     16.6
Minimum          0.9 day 29
Maximum          22.2 day 16
Highest Minimum  15.8 day 13
Lowest Maximum   11.3 day 30
Air frosts       0
Rainfall (mm):
Total for month  12.6
Wettest day      2.8 day 18
High rain rate   12.1 day 11
Rain days        8
Dry days         23
Wind (mph):
Highest Gust     23.5 day 02
Average Speed    3.4
Wind Run         2495.1 miles
Gale days        0
Pressure (mb):
Maximum          1034.0 day 27
Minimum          996.3 day 19
Days with snow falling         0
Days with snow lying at 0900   0
Total hours of sunshine        0.0

 

September 2017: average temps, rain. Dull

The first month of autumn continued in the same vein as the last month of summer .

The mean temperature finished 14.8C, 0.6C below average and very similar overall to September 2013.Screen Shot 2017-10-02 at 09.34.34

Some 53.5mm of rainfall was recorded, 103% of the 1981-2010 average. Some 114 hours of sunshine were recorded, 81 per cent of average, so on the dull side.

Overall the month was typical for early autumn – though possibly felt more autumnal because it was around 3C cooler than September 2016 and much wetter and duller than that month.

As usual at this time of year there is already much speculation about how cold the coming winter may, or may not, be. Winter has arrived over Siberia and early season snow cover is predicted to increase over the next week. However, the factor of early snow over Siberia being a sign of a cold winter to come in NW Europe is is only one piece of the jigsaw and I have seen it proved wrong a few times.

 

Summary for September 2017
Temperature (°C):
Mean (1 minute)  14.4
Mean (min+max)   14.8
Mean Minimum     10.7
Mean Maximum     18.9
Minimum          5.3 day 21
Maximum          22.7 day 04
Highest Minimum  16.7 day 04
Lowest Maximum   15.2 day 19
Air frosts       0

Rainfall (mm):
Total for month  53.5
Wettest day      16.1 day 27
High rain rate   16.1 day 13
Rain days        19
Dry days         11

Wind (mph):
Highest Gust     28.9 day 12
Average Speed    2.3
Wind Run         1670.8 miles
Gale days        0

Pressure (mb):
Maximum          1022.7 day 01
Minimum          989.1 day 12

Total hours of sunshine        114 (81%)

To view full stats follow this link:http://1drv.ms/1kiTuzv

Screen Shot 2017-10-02 at 09.01.01

 

July 2017: wettest since 1960

July 2017 was the wettest since 1960. Some 92.3mm of rain were recorded which is 212 per cent of the 1981-2010 average.finger cloud on 7th

Although the opening third of the month saw a continuation of the June heatwave temperatures gradually returned to normal values to leave the mean for the month at 19.2C, that’s 0.7C above average.

With all the rain sunshine totals were down. Some 167 hours were recorded, that’s 87% of average.

Though the rainfall total was impressive it is well short of the record of 164.2mm set in 1834, and is only 35th in the list going back to 1797.underlit

Summary for July 2017

Temperature (°C):
Mean (1 minute) 18.9
Mean (min+max) 19.2
Mean Minimum 14.7
Mean Maximum 23.7
Minimum 9.4 day 12
Maximum 30.5 day 07
Highest Minimum 18.3 day 06
Lowest Maximum 19.0 day 24
Air frosts 0

Rainfall (mm):
Total for month 92.3
Wettest day 30.8 day 11
High rain rate 56.4 day 29
Rain days 10
Dry days 21

Wind (mph):
Highest Gust 17.4 day 27
Average Speed 2.9
Wind Run 2163.5 miles
Gale days 0

Pressure (mb):
Maximum 1024.2 day 16
Minimum 996.8 day 31

Total hours of sunshine 167

In terms of the rest of the summer a look at the ECMWF control run out to 10 days suggests an unsettled start to August with the jetstream centred right over the top of the UK. Things may improve as the Azores high attempts to exert more influence – so perhaps more in the way of sunshine than of late. In terms of heatwaves it is impossible to tell at this range.mid level

Here follows the full weather diary for July. To view full stats follow this link:http://1drv.ms/1kiTuzv

1st: Cloudy but with sunny spells developing, these growing longer in length by evening.
2nd: Sunny with just a few light cumulus.
3rd: Sunny start though with plenty of cloud around, this tending to thicken after lunch with odd spot of rain.
4th: Sunny and very warm early then tended to cloud over before sun returned in the late afternoon and evening. Some very unstable low to mid level cloud.
5th: Sunny with just a few cirro-cumulus. Feeling very warm with cloud bubbling up in the evening, however forecast storms failed to materialise.
6th: Sunny with cirrus and dotted cumulus. This tended to thicken late morning though sun stayed out and became hot and humid.
7th: Sunny with lots of high-level cirrus and cumulus most of the day.
8th: Bright but mostly cloudy start, the cloud tending to vary through the day. Sunny after 4pm. Warm overnight.
9th: Bright but mostly cloudy start, the cloud tending to break and vary through the day.
10th: A mostly sunny morning and lunchtime until 2pm when it clouded over.
11th: Cloudy with some bright breaks at first. Cloud thickening with rain by noon, this falling sporadically before getting going after 5pm and stopping by 3am.
12th: Cloudy, damp and close start.
13th: Sunny with variable cloud until noon when there were just bright spells.
14th: Cloudy but with a few breaks around mid morning. Turning cloudy again before sunny spells in the evening.
15th: Cloudy with some sporadic rain as warm front blew through and close. Very limited brightness.
16th: Cloudy with some bright spells. Feeling warm and humid.
17th:Sunny with just a few cirrus drifting around. Feeling hot, cloud thickened from the west in the late afternoon.
18th: Sunny with variable cirrus and cirro cumulus through the day. Feeling very warm. Storms began building with supercell to west of London and over Chilterns.
19th: Cloudy, dull start and very humid with heavy mist – the cloud tended to lift to give sunny spells in the afternoon.
20th: Drizzle after shower before obs time, then showers through to 1pm.
21st: Cloudy start but with sunny spells developing. Clouded over in evening with intermittent heavy rain at 11pm and through the early hours.
22nd: Cloudy but with sunny intervals developing around noon. Heavy showers developing with thunder at 2.30pm and 3.07pm.
23rd: Bright with variable cloud
24th: Cloudy with light, showery rain from northerly airstream that originated in the Med.
25th: Cloudy with light rain just after obs time.
26th: Cloudy with occasionally rain. Feeling warm and a late clearance. Breezy and chilly overnight.
27th: Cloudy but bright and sunny spells developing. A very heavy shower at 1pm.
28th: Bright start but clouding over.
29th: Sunny start with cloud increasing after noon to leave overcast before patchy rain moved in. This falling more heavily at 5pm before clearing to further showers. More rain overnight before a strong squall arrived at 2.45am and lasted an hour with further bursts of rain through the night –  two claps of thunder and lightening during squall.
30th: Sunny with variable cloud through the day. Very warm in the sunshine
31st: Sunny with variable cloud throughout the day.

June 2017: very warm

June 2017 has been a month of real contrasts. A thundery deluge on the 2nd was followed by conditions typically brought by the European monsoon.

rainfall
24hr rainfall totals

Warm weather followed in the second week before a full-blown heatwave arrived bringing the hottest June spell since 1976.

The mean temperature for the month finished at 18.9C, that’s 2.8C above average. It was the second warmest June in a local record going back to 1797. Though it was only 0.4C cooler than 1976 it was also much wetter than that very dry month.

Though it appeared a wet month, over two-thirds of the recorded rain fell in two episodes.

Sunshine for the month was 202.3hrs, 114% of average.

In terms of the rest of the summer you would be forgiven for thinking that we have already had more than our fair share of good weather. One way of looking at it is to count the number of days the mercury rises above 25C with 10 hrs of sunshine. Since May that has happened on 13 occasions – far higher than anything in the past four years.june heat

It will be interesting to see if July and August, normally the months where we get most of our summery weather are as good as June.

Summary for June 2017
Temperature (°C):
Mean (min+max)   18.9
Mean Minimum     13.8
Mean Maximum     23.9
Minimum          9.9 day 12
Maximum          31.5 day 21
Highest Minimum  21.1 day 21
Lowest Maximum   16.7 day 28
Air frosts       0
Rainfall (mm):
Total for month  71.1 (138.9%)
Wettest day      31.2 day 02
High rain rate   108.4 day 02
Rain days        8
Dry days         22
Wind (mph):
Highest Gust     27.3 day 05
Average Speed    3.5
Wind Run         2550.5 miles
Gale days        1
Pressure (mb):
Maximum          1025.0 day 16
Minimum          984.2 day 05
Total hours of sunshine        202.3
Here follows the full weather diary for June. To view full stats follow this link:http://1drv.ms/1kiTuzv

1st: Sunny with scattered cumulus through the morning, the cloud thicker during the day.
2nd: Cloudy start though brightening up with long sunny spells. Cloud bubbled up and a heavy thunderstorm moved in at 3.15pm and lasted an hour. Sunny again by 6pm.
3rd: Bright start with decreasing cloud.
4th: Sunny start though cloud bubbling up late morning into early afternoon. Cloudy and breezy with a few spots of rain at dusk.
5th: Cloudy and very breezy start. Bright at times.
6th: Rain and very windy to start with gale force 9 in Channel. Rain lasted into the early afternoon before clearing to bright spells. Odd shower overnight but remained blustery with a few trees down. Flowering cherry fell at mum’s at 6.30pm.
7th: Sunny with long sunny spells. An area of rain after dark then overcast through the night.
8th: Cloudy and breezy, a shower at noon and some bright spells at 1pm.
9th: Sunny though breezy with lots of cloud. Spots of rain in the wind.
10th: Sunny and warm start with lots of sunshine. Very breezy.
11h: Sunny and feeling very humid but breezy. Alternating between very warm sunshine and cloud. Very brief few drops of rain at dusk then mostly cloudy night.
12th: Sunny periods throughout the day. Cloudier at times. Clear overnight with warm, sunny start.
13th: Sunny, clear start and feeling warm early.
14th: Sunny most of the day with odd cumulus. Very warm though turning a bit fresher overnight.
15th: Sunny morning though with more cloud than yesterday. A fresh breeze developing.
16th: Sunny with variable cloud. Warm.
17th: Sunny though lots of hazy cumulus.
18th: Sunny though much cloud amid the humidity. Felt airless with only limited breeze. Oppressive overnight.
19th: Sunny with cloud decreasing
20th: Bright start though cloud breaking at 11am to leave clear afternoon with just a couple of cumulus.
21st: Sunny and hot all day with patchy cirrus. Warmest June day since 1976 at Heathrow 33.9C. Warm overnight but more of a breeze. Sunny early.
22nd: Very brief rain shower at obs time then sunny intervals. Cooler but still humid. Very breezy overnight.
23rd: Long sunny spells with hazy cumulus. Although cooler still hot in the sunshine. Cooler overnight and breezy.
24th: Mostly cloudy though bright. A sharp shower in the evening.
25th: Bright though mostly cloudy. A couple of bursts of drizzle but then sunny spells late evening.
26th: Sunny with lots of cirrus, cirrocumlus and a fallstreak hole in the sky. Warm but low humidity.
27th Sunny start though sun becoming scarce. Patchy light rain at 10.30am and thunder then a heavy shower at 3.45pm. Rain in the evening that lasted into the early hours.
28th: Cloudy and very dull at times with very light drizzle. Humid.
29th: Cloudy though bright with some sunny intervals.
30th Sunny though with lots of cloud. Decreasing cloud in the afternoon and a pleasant evening.