Saturday, 1 July 2017

Weather log June 2017

Pertinenet daily notes June 2017

Key LL = Long Lawford; CL Church Lawford, Warwickshire; MH Milford Haven, Pembrokeshire

Changeable start to June:

Sat 3rd ground frost parts of Wales (Llanwnnen 1.4c, Swyddfynnon 1.9c) cf quite a mild showery night Midlands (e.g. Coventry min 10.5c)

Sun 4th probable ground frost at Llanwnnen (air min 2.5c) about the only spot as next lowest min Shobdon 4.4c (grass min +1c)

Then a proper unsettled spell:

Mon 5th cool, dull and wet in many places, much of Wales having a very wet day with over an inch widely, and over 100mm for Snowdonia and some other high ground (Capel Curig 49mm 12 hours to 1800), parts of the Midlands having only small amounts though during the day (Nottingham & Pershore 3mm 06-1800). Llanwnnen max 13.9c was cooler than any day in May; other maxima Capel Curig 13.3c, Pembrey Sands 15.0c, Hereford & Pershore 16.0c). The low responsible was centred over Wales by evening, pressure dropping to 988mbar at Llanwnnen lowest since March.

Tue 6th WW had further overnight rain with large totals the north in particular  (Capel Curig 83mm and Whitechurch c. 81mm in 24 hours to 0400). At Llanwnnen 50.5mm fell in 25 hours to 0600, with 40.0mm for the rain day, the wettest since May 14th 2013 and it was the second wettest June day here (42.0mm 6-6-09). Other totals Coventry 27.0mm rain day; 06-0600 totals Mona 50mm, Trawsgoed 46mm, Aberporth 40mm; Long Lawford 14mm 0830-0830. Another cool windy day, although only a few showers WW (Capel Curig 12.3c, Valley 16.3c, Pershore 16.6c)

Turned drier and warmer mid month:

Wed 14th warm generally with sunny periods, especially Midlands (Pershore 25.9c, Shobdon 13.3 hrs)

Then a notable June heatwave:

Sat 17th unbroken sunshine in many areas, warm to very warm WW and a hot June day much of Midlands where widely above 27c, usual cooler exposed exceptions (Pershore 29.2c, Llanwnnen 26.1c, Aberdaron 15.8c)

Sun 18th hot and sunny in many places, very hot in some (Hereford 30.2c, Church Lawford 29.7c, Llanwnnen 28.6c, Aberporth 21.8c)

Mon 19th hot to very hot inland, very warm even for many coasts. Hottest June day on record here at Llanwnnen max 29.7c; other readings Pershore 31.9c, CL 30.8c, Trawsgoed 28.3c, MH 27.7c, Aberdaron & Valley 24.0c)

Tue 20th warm sultry night away for many (min Mumbles 19.4c, Coventry 17.5c, Mona 11.4c). Very warm to very hot; Llanwnnen very sultry max 30.1c, again a new June record and a first 30c plus for the month, with dew points as high as 21.2c. Wales and the Marches seeing the highest readings while a weak cold front brought much lower temps to the NE Midlands (Porthmadog c. 30c, Trawsgoed 28.0c, Pembrey Sands 27.3c, Hereford 28.6c, Nottingham max 18.9c). At midnight temps still at 23c or 24c over much of the Midlands!

Wed 21st culmination of the heatwave, more cloud with hazy sunny spells, very hot and humid widely. Overnight low 16.1c here at Llanwnnen a new record. By day many places very hot and humid, a few thundery showers affected WW. Again the June temperature recored broken max 30.6c at Llanwnnen, while dew point attained 22.4c, second highest to last July (22.5c) Other maxima Wellesbourne 32.2c, Pershore 31.8c, CL 30.0c, Trawsgoed 30.2c, Aberporth 28.7c, MH 24.1c. Heathrow max 34.5c was the highest UK reading in June since 1976.

Thu 22nd another warm night much of Midlands above 16c (CL min 17.2c). Much cooler by day though, by over 10c in places, a few brief thundery showers over the Midlands with thunder heard LL early morning (Pershore 22.1c, Pembrey 20.0c, Aberdaron 16.1c)

Fri 23rd rain affected much of Wales, much of Midlands escaped mostly dry (Gogerddan 18.8mm wettest in UK)

Midlands tending to miss the rain next few days too:

Sat 24th rather warm with sunny intervals Midlands, rather cloudy and near average WW (Wellesbourne 25.0c)

Unsettled and very cool end to month:

Wed 28th cool, overcast and damp (Nottingham max 12.6c, Capel Curig 13.0c, Llanwnnen & Pembrey 16.8c, Pershore 15.3c; Ross-on-Wye 31mm)

Thu 29th notably cool late June day for many areas and in particular WW.  Llanwnnen max 12.7c was the lowest such reading for so advanced into Summer (cf 12.6c 25/06/07 and 13.7c 02/07/12). Other maxima Aberdaron 11.3c, Aberporth 11.7c, Coton-in-the-Elms 13.2c, Wellesbourne 15.4c.

Fri 30th very cool/ cool with some drizzle WW and Marches, nearer average rest of Midlands (Aberdaron max 12.3, Aberporth 12.6c, Mumbles 15.8c, Shawbury 16.0c, Pershore 20.8c; Scolton Country Park, Pembs 26.2mm wettest in UK)

June 2017 summary

Midlands warm with near average rainfall and sunshine

WW generally wet or very wet, quite warm, rather dull, rainfall aberage parts of South Wales

June rainfall totals

Valley 129.8mm (251%)

Capel Curig 251.0mm (180%)

Llanwnnen 121.3mm (178%)

Pembrey Sands c. 85mm
Llanelli 63.2mm
Mumbles 62.2mm (97%)

Shawbury 46.0mm (86%)

Hereford 37.6mm (83%)
Pershore 33.4mm (66%)

Long Lawford 48.7mm (98%)

Church Lawford 50.2mm (90%)
Coventry, Bablake School 64.0mm
Daventry c.38mm
Crick c. 38mm


Valley 155.7 hrs (86%)

Aberporth 171.6 hrs (88%)
Llanwnnen 128 hrs estimated (79%)

Bablake 163.6 hrs