Monthly Weather Bulletin December 2007

December began and ended with

unsettled conditions, caused by

depressions off the northwest coast,

but high pressure near the country

around the middle of the month

brought mainly fair weather. Strong

winds were recorded at most stations

during the first week and again

between the 26th and 29th, but the

period around mid-month was

relatively calm. Rainfall totals were

highest over the western half of the

country, with heavy falls at times

between the 1st and 9th, occasionally

accompanied by thunder, and also

between the 23rd and 28th. Little or

no rain was measured at many

stations between the 10th and 21st,

however, and the total number of

wetdays during the month (days with

1mm or more rainfall) was close to

the normal range for December of

between 13 and 20. Most of the

month was mild, especially the first

week, but minimum temperatures fell

close to or below normal between the

17th and 25th, bringing widespread

ground frost. There was no air frost

during the month in most coastal

locations, while the total number of

air frosts recorded at the majority of

inland stations of between 4 and 6

Monthlyy Weather

Bulletin

N

No

o.. 2

26

60

0

DECEMBER 2007

Stormy weather at the beginning of the month brought exceptionally rough sea conditions along the west coast, with record high waves measured by Atlantic weather buoys- see page 2.

(picture: Irish Examiner)

INSIDE

INSIDE

on west coast- on west coast- page 2page 2

Wind &

Wind &

Elements ...

Elements ...

4

4

Marine &

Marine &

Pr

Pr

essur

essur

e ...

e ...

5

5

Agmet /La

Agmet /La

b

b

...

...

6

6

Diary ...

Diary ...

8

8

R

R

ainf

ainf

all ...

all ...

10

10

T

T

emper

emper

a

a

tur

tur

e ...

e ...

12

12

Sunshine ...

Sunshine ...

14

14

W

W

or

or

ld

ld

W

W

ea

ea

ther

ther

..

..

15

15

T

T

he W

he W

ea

ea

ther

ther

of

of

2007...

2007...

16

16

Warmest year on Warmest year on record in places record in places

Produced by Met Éireann, Glasnevin Hill, Dublin 9. Annual subscription 80 euro

For more information-tel: +353-1-8064260 fax: +353-1-8064216 [email protected] www.met.ie

Notes on the tables and map showing location of stations appear in each January issue

was only around half of the normal

number for December. An exception

was Mullingar, where 10 air frosts were

measured. Sunshine totals were above

normal in most places, especially in the

east; Dublin Airport’s total was more

than twice the amount recorded in

parts of the west and north.

2

WEATHER

A succession of Atlantic storms that passed close to Ireland in late November and early December 2007 generated unusually severe offshore conditions, with very high seas along the western seaboard. Between December 7th and 9th, a slow-moving depression of central pressure 966hPa (see image below) brought stormy conditions and exceptionally high waves of over 17 metres, as had been forecast by the numerical wave model from the beginning of the month. This model is driven by information from the network of weather buoys around the Irish coast operated by the Marine Institute, together with weather reports from Met Eireann and global wave model data from the US Navy forecast model FNMOC. Waves can be forecast up to 2 days ahead on the Irish model and up to 6 days ahead on the European global model. Shown on the right is the forecast chart from the Marine Institute-adapted wave model,

six days ahead of the weekend of the December 8th/9th, showing significant wave heights of between 14 and 16 metres anticipated off

Ireland’s west coast.This forecast was broadcast though the normal Met Eireann weather reports on both television and radio, alerting both commercial interests and the public to what was on the way.

The chart below shows data recorded by the M6 buoy, located approximately 300km west of the Galway coast, as the storm centre passed eastwards over Ireland. It shows that, just after midnight on the 9th, a significant wave height was recorded of 17.2m, with a period of 14 seconds; this was the highest wave ever measured by any of the Irish buoy network. Slightly further west, the U.K. moored buoy K3 (see chart left) recorded a wave of 18.3m at 2100UTC on the 8th, exceeding the previous record from a U.S. buoy of 17.9m, recorded in September 2004 during Hurricane Ivan. Wave heights at the Irish M3 buoy, off the southwest coast, reached 13.8m at 0500UTC on the 9th, exceeding the previous highest value there of 12.9m, recorded in January 2005(see also page 5).

R

R

ecor

ecor

d high w

d high w

a

a

v

v

es of

es of

f

f

Irish coast on 9th

Irish coast on 9th

0000UTC 1200 0000 1200 0000 1200 0000 7th 8th 9th

50

45

40

35

30

25

20

15

10

5

0

20

18

16

14

12

10

8

6

4

2

0 Wave Height

(metres) Mean windspeed

(knots)

Hourly windspeeds and wave heights between December 7th and 9th at M6 Buoy (53.06°N 15.93°W)

Six-dday forecast of significant wave heights for 0600UTC on December 9th

16 14 12 10 8 6 4 2 0 m

Infrared satellite image at 1800UTC on 8th, showing location of weather buoys

Δ MM66

M M33 _Δ K

1st to 9th: A series of deep Atlantic

depressions passed close to the northwest

of Ireland, with their associated frontal

systems bringing rain or showers each day,

accompanied by strong, mainly

southwesterly winds. Heaviest falls were

recorded on the 1st and 2nd in western

areas and more generally on the 6th and

8th; during this 10-day period, close to

100mm of rain was measured in parts of

the west and southwest, causing localised

flooding. Gales were frequent near Atlantic

coasts, generating a huge sea swell. A wave

measuring 17.2m was recorded at midnight

on the 9th by the M6 weather buoy,

located approximately 300km off the west

coast; this was the highest wave ever

recorded off the Irish coast (see page 2).

Temperatures during this period were well

above normal with no air frost.

10th to 21st: An anticyclone to the south

of Ireland moved slowly northeastwards to

become centred over the North Sea. This

period was dry apart from some light rain

or showers in western areas at first, with

heavy rain in the extreme southwest on the

12th. Daytime temperatures fell close to or

below normal, while ground frost became

more widespread and severe in some

midland and eastern areas between the

17th and 21st. Winds backed to a

southeasterly direction during the period,

becoming light to moderate generally.

22nd to 31st: Atlantic depressions again

moved close to the northwest coast,

bringing a return to wet and windy

conditions over Ireland. Heaviest falls were

in the period 27th/28th. Frost was

widespread early in the period, but milder

conditions returned by the end of the

month.

Wind and elements: Mean windspeeds

for the month of between 9 and 17 knots

(17 and 31km/h) were above normal

everywhere and were the highest for

December for between 8 and 24 years in

many places. The highest gust, 68 knots

(126km/h), was measured at Belmullet on

the 4th. Thunder was widespread over the

western half of the country on the 1st,

with isolated thunderstorms also on the

2nd, 5th, 7th, 9th and 28th. Hail was

recorded in the periods 1st to 2nd, 7th to

9th, on the 25th and between the 28th to

30th. The only report of snow was from

Knock Airport on the 28th. Fog was

observed in the periods 4th to 9th, 19th to

21st and 24th to 28th.

3

WEATHER

Right

Air temperatures were well above normal during the early part of the month, with both maximum and minimum values around five degrees higher than the December normal in the period between the 4th and 6th. Cork Airport’s maximum of 13.8°C on the 6th was the highest for December at the station since it opened in 1962, while Shannon Airport’s highest value of 15.3°C on the 4th was its highest December value since 1948. A maximum value of 15.8°C at the automatic station at Fermoy (Moorepark), Co. Cork, on the 6th, was the highest December value at the station since it opened in 1966. The highest ever December temperature in Ireland of 18.1°C was measured at Peamount, Co. Dublin, in 1948.

Kilkenny Shannon

Valentia

16

14

12

10

8

6

4

WIND & ELEMENTS

F

REQUENCY OF WIND DIRECTION

CO. CLARE

SHANNON AIRPORT 12.6 270° 42 7/01 270° 59 2/1348 4 14 103 0 0 5 1 2

CO. CORK

CORK AIRPORT 12.7 310° 36 9/14 310° 55 9/1414 1 14 110 0 0 0 0 5

CO. DONEGAL

MALIN HEAD 16.5 150° 38 13/08 150° 56 13/0743 6 22 230 0 0 4 1 0

220° 38 27/04 220° 56 27/0317

CO. DUBLIN

CASEMENT AERODROME 11.8 260° 34 8/14 250° 52 7/0032 1 16 99 0 0 0 0 0

DUBLIN AIRPORT 12.8 260° 38 8/14 260° 53 8/1357 3 13 100 0 0 0 1 2

CO. KERRY

VALENTIA OBSERVATORY 14.4 260° 43 9/02 250° 64 9/0050 4 16 182 0 0 2 1 0

CO. KILKENNY

KILKENNY 8.7 280° 27 2/12 260° 43 29/1055 0 10 26 n/a 0 --- n/a ---

CO. MAYO

BELMULLET 17.0 190° 43 4/19 190° 68 4/1939 8 23 274 0 0 7 1 0

KNOCK AIRPORT 12.6 250° 37 29/08 260° 50 8/1152 2 16 93 1 0 2 0 12

250° 50 29/0739

CO. MONAGHAN

CLONES 9.1 260° 26 1/18 270° 45 1/1755 0 9 17 n/a 0 n/a

---CO. OFFALY

BIRR 9.4 280° 24 2/15 280° 44 8/1353 0 10 20 n/a 0 n/a

---CO. WESTMEATH

MULLINGAR II 8.4 270° 22 2/13 250° 42 2/1138 0 5 10 n/a 0 n/a

---CO. WEXFORD

ROSSLARE 11.7 190° 28 4/23 220° 52 9/0252 0 16 118 n/a 0 n/a

---W

IND

((

KNOTS

))

E

LE

EME

ENTS

County /

Station

Valentia Observatory

Dublin Airport

N

NE

NW

NW

SW

SW

W

_W

SE

SE

NE

N

E

S

E

S

Calm: 0.0%

_{Calm: 0.1%}

0 1 2 3 4%

December 2007

Mean Max. 10-min. mean Max. Gust Days with Hours with

5

MARINE & PRESSURE

HHoouurrllyy w

wiinndd aanndd w

waavvee ccoonnddiittiioonnss aatt M

M33 ((5511°°1133’’NN,, 1100°°3333’’W

W))

Wind Direction

Wind Speed

Sea Temperature

Wave Height

dd

ee

gg

rree

ee

ss

ffrr

oo

mm

nn

oo

rrtt

hh

kknn

oo

ttss

°°CC

360 300

200

100

0

14

13

12

11

10

9 50

40

30

20

10

0

1 5 10 15 DATE 20 25 31

M

E

EA

AN

N

A

T

TM

MO

OS

SP

PH

HE

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C

P

R

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Mean sea level pressure values for the month ranged

from 1012hPa in the north and northwest to over

1017hPa in the southeast, around 4hPa above

normal for December. The early part of the month

was dominated by low pressure, however, as deep

Atlantic depressions passed close to or over Ireland.

Claremorris measured the lowest value of the

month, 967.7hPa on the 9th. Pressure rose sharply

thereafter and the month’s highest value, 1040.6hPa,

was measured at Malin Head on the 18th.

M

Meeaann ddaaiillyy M

Meeaann SSeeaa LLeevveell pprreessssuurree

mm

ee

ttrr

ee

ss

15

12

9

6

3

0

40˚N 50˚N 60˚N 70˚N

H 1028 H

1024

L 988

L 1017

1000 1000

1000

100 8

1008

1

1016

1016

1024

1024

1024

1024 December 2007

M

ARINE

O

BSERVATIONS FROM

I

RISH

M

ARINE

D

ATA

B

UOY

N

ETWORK

Monthly mean MSL pressure, based on 1200 UTC values

SSuum

mm

maarryy ooff M

Meeaann M

Moonntthhllyy VVaalluueess

M6



_M5

z

Malin Head

M4

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

M2

M3

_

Sea Mean Max. Mean Max.

Buoy surface wind 10-min wave wave temp. speed wind height height

(°C) (knots) (knots) (m.) (m.)

M2 11.4 20.9 38 1.8 3.9

M3 11.9 23.7 48 5.0 13.8

M4 11.1 23.0 39 4.5 10.2

M5 11.6 20.2 38 2.2 6.0

M6 12.8 23.4 49 5.8 17.2

Malin 9.3

Head

980 990 1000 1010 1020 1030 1040

6

AGMET / LABORATORY

CO. CLARE

SHANNON AIRPORT 6.7 7.3 8.1 CARRON 7.1 7.7

CO. CORK

FERMOY (MOORE PARK) 7.2 7.5 7.9 CORK AIRPORT 6.6 7.2 8.2 SHERKIN ISLAND 9.2 9.8 BALLINCURRIG (PEAFIELD) 6.3 7.0 7.4

CO. DONEGAL

MALIN HEAD 6.2 7.3 8.4 CO. DUBLIN

DUBLIN AIRPORT 4.7 5.3 5.9 CASEMENT AERODROME 4.6 5.2 6.5

CO. KERRY

VALENTIA OBSERVATORY 8.3 8.7 9.6 CO. KILKENNY

KILKENNY 5.3 6.0 6.7 CO. LIMERICK

MOUNT RUSSELL 6.8 7.2 CO. LOUTH

ARDEE (BOHARNAMOE) 5.8 5.4 5.9 CO. MAYO

BELMULLET 7.1 7.9 8.7 STRAIDE 6.7 KNOCK AIRPORT 4.4 5.2 6.4

CO. MEATH

WARRENSTOWN 4.6 5.5 6.2 CO. MONAGHAN

CLONES 5.0 5.6 6.3 CO. OFFALY

BIRR 5.4 6.6 7.5 CO. TIPPERARY

FETHARD (PARSONSHILL) 5.9 6.7 CO. WATERFORD

DUNGARVAN (CARRIGLEA) 7.6 7.9 CO. WESTMEATH

MULLINGAR II 5.1 5.7 6.4 CO. WEXFORD

JOHNSTOWN CASTLE 6.3 6.7 7.0 ROSSLARE 6.7 7.2 8.0 JOHN F. KENNEDY PARK 6.3 7.1 8.5 CLONROCHE (KNOXTOWN) 6.6 7.0 7.7

100mm 200mm 300mm County/

Station

Soil Temperatures at 0900UTC

Mean 100mm

Soil Temperatures (°C)

at 0900UTC

(difference from 1961-90 normals in brackets)

°C

Soil Moisture Deficits (mm)

10th of month / 31st of month

(0 represents field capacity, -10 saturation)

6.2

(+1.1)

4.4

5.0

(+0.5)

6.7

(+1.4)

8.3

(+1.7)

5.3

(+0.9)

6.7

(+0.9)

5.4

(+0.8)

6.6

(+1.0)

5.1

(+0.9)

4.6

(-0.1)

1/-2

0/-10

-1/-7

0/-7

0/-1

_0/0

1/1

0/1

0/-6

-1/-3

0/-1

0/1

7.1

(+1.1)

NO2-N   

SO2-S „ „ „

SO4-S z z z

(μgs/m3₎

electrical conductivity

(

μ

S/cm)

Chemical Analysis of Precipitation and Air Samples

at Valentia Observatory

Acid rain occurs when pollutants combine with moisture in the air to form sulphuric or nitric acid. pH is the simplest way of measuring the acidity of precipitation. Usually pH of 7.00 is considered neutral but this is not the case in rainfall samples. Pure water in the atmosphere has an equilibrium pH value of 5.65 at 20°C owing to carbon dioxide in the air dissolving to form carbonic acid. Any value below pH 5.65 is considered acid while any value above is considered alkaline.

Sulphur dioxide and sulphate in air contribute to the formation of sulphuric acid; nitrate in air contributes to the formation of nitric acid.

Conductivity measures the total ion activity in the rainfall, i.e. the higher the conductivity the greater the number of ions present.

pH

December 2007

data shown here are interim values and are subject to change 0 250 500 750 1000 3 4 5 6 7 PRECIPITATION

pH and electrical conductivity are not available on dry days (<0.2mm)

0 0.5 1 1.5 2 2.5

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31

AIR

7

AGMET

M

M

P

P

E

E

((P

P..E

E..))

ANNDD

S

S

M

M

County/ P.E. (mm) Soil Moisture (mm)

Station Period Amount Deficit Accum’ltd Deficit Surplus

M

M

E

E

((

))

C

C

A

A P

P

Rainfall (mm) Evaporation (mm) Clare Kilmaley 249.8 22.5

Cork Fermoy (Moorepark) 98.8 16.2

Kerry Valentia Observatory 189.5 53.6

Kildare Poulaphuca 101.6 15.2

Mayo Newport (Furnace) 205.5 0.1

Offaly Derrygreenagh 105.4 1.7

Waterford Dungarvan (Carriglea) 110.3 12.3

Wexford Johnstown Castle 88.5 18.7

P

P..E

E..

(Penman)

Station month (mm)

G

G

S

S

R

R

(MJ/sq. m.)

10-day totals Total for 1-10 11-20 21-end month

S

J

1-10 Valentia Obs. 11-20

21-end

month Co. Wexford

1-10 Johnstown Castle 11-20 21-end

month

16.9 - 0 65 10.9 - 0 22 11.1 - 0 67

38.9

6.2 - 0 46 8.3 8 8 -7.7 - 0 27

22.2

Co.Clare

Shannon Airport

Co.Cork

Cork Airport

Co.Donegal

Malin Head

Co.Dublin

Dublin Airport Casem’t Aerodrome Co Kerry

Valentia Obs.

Co.Kilkenny

Kilkenny

Co.Mayo

Belmullet Knock Airport

Co.Monaghan

Clones

Co.Offaly

Birr

Co.Westmeath

Mullingar

Co.Wexford

Rosslare

13

1

18

2 5

23

1

5 1

0

3

0

9

11.17 12.83 15.16 39.16

24.11 17.61 23.78 65.50

22.71 18.30 18.98 59.99

22.98 17.11 20.87 60.96

14.91 14.93 17.88 47.72

14.62 15.05 17.71 47.38

19.27 17.60 20.04 56.91 December 2007

Co. Cavan 1-10 89.8 - 9 8 10.4 3.9 7.2 - 0.6 10 0 31 4 -3.1 10 3 - - 12.8 - Cavan (Loreto) 11-20 0.3 - 1 0 8.4 2.1 5.3 - -2.2 17 4 18 0 -4.6 17 4 - - 10.3 - 21-end 57.2 - 9 7 10.0 1.1 5.6 - -5.0 22 4 27 2 -8.0 21 6 - - 13.8 -

month 147.3 - 19 15 9.6 2.3 6.0 - -5.0 22 8 75 6 -8.0 21 13 - - 36.9 -

Co. Cork 1-10 62.8 - 9 8 13.1 5.9 9.5 - 2.5 8 0 52 11 -3.1 10 4 8.2 8.9 17.2 - Fermoy 11-20 1.5 - 2 1 9.2 4.8 7.0 - -1.0 11 1 28 1 -6.0 11 5 6.9 7.5 5.8 -

21-end 34.5 - 9 8 10.6 4.2 7.4 - -1.7 23 2 38 4 -6.5 23 6 6.7 7.3 15.8 -

month 98.8 91 20 17 10.9 5.0 8.0 2.2 -1.7 23 3 118 15 -6.5 23 15 7.2 7.9 38.8 95

Co. Donegal 1-10 105.3 - 9 9 11.1 3.5 7.3 - 0.1 10 0 33 5 -1.9 10 2 - - - - Glenties 11-20 13.4 - 3 3 8.4 3.9 6.2 - -1.6 19 1 23 1 -3.1 19 5 - - - - 21-end 74.6 - 10 10 9.6 3.4 6.5 - -0.9 23 1 28 1 -2.5 23 7 - - - -

month 193.3 114 22 22 9.7 3.6 6.7 1.5 1.6 19 2 84 7 3.1 19 14

-Co. Kerry 1-10 74.9 - 9 9 12.7 6.4 9.6 - 4.6 1 0 52 9 -3.0 10 1 - - n/a - Ardfert 11-20 1.8 - 2 1 9.9 5.7 7.8 - 2.2 18 0 36 3 -5.0 18 7 - - n/a - 21-end 58.2 - 9 8 10.9 5.4 8.2 - 1.5 25 0 43 4 -5.5 25 7 - - n/a -

month 134.9 - 20 18 11.2 5.8 8.5 1.8 1.5 25 0 130 17 -5.5 25 15 - - n/a -

Co. Louth 1-10 38.9 - 7 6 10.5 4.7 7.6 - 1.8 8 0 34 5 1.0 1 0 6.8 7.1 - - Ardee 11-20 0.9 - 2 0 8.2 2.5 5.4 - -0.7 11 3 17 0 1.0 11 0 5.3 5.4 - -

21-end 27.2 - 8 6 9.7 1.2 5.5 - -4.1 22 5 26 2 1.0 31 0 5.2 5.2 - -

month 67.0 94 17 12 9.5 2.8 6.2 1.2 -4.1 22 8 78 7 1.0 1 0 5.8 5.9 - -

Co. Waterford 1-10 69.6 - 8 8 12.9 6.0 9.5 - 3.1 8 0 51 10 -0.4 10 1 - 8.9 24.1 - Dungarvan 11-20 0.0 - 0 0 9.7 5.3 7.5 - -2.4 11 1 33 1 -3.5 11 1 - 7.5 7.1 - 21-end 40.7 - 10 8 10.8 4.2 7.5 - -3.0 23 2 39 4 -4.3 23 3 - 7.5 11.9 -

month 110.3 - 18 16 11.1 5.1 8.1 1.9 -3.0 23 3 123 15 -4.3 23 5 - 7.9 43.1 97

Co. Wexford 1-10 46.6 - 9 8 11.7 5.6 8.7 - 2.3 3 0 44 7 -0.6 3 1 7.4 8.1 22.4 - Johnstown Castle 11-20 0.0 - 0 0 8.4 3.9 6.2 - 0.2 11 0 21 1 -4.0 11 5 5.2 6.3 15.9 - 21-end 41.9 - 9 7 10.5 4.3 7.4 - 0.3 23 0 36 3 -3.6 23 5 6.2 6.6 9.5 -

month 88.5 80 18 15 10.2 4.6 7.4 1.1 0.2 11 0 101 10 -4.0 11 11 6.3 7.0 47.8 102

S

Stta

attiio

on

n

period

R

T

S

(MM) (HOURS)

10-

A

S

Saturday 1st:It was a cold, windy day with scattered showers and some short sunny spells. Some of the showers were heavy and accompanied by thunder, with some wintry showers also. Continuing windy after dark with shower activity decreasing. Moderate to fresh and gusty southwesterly winds increased fresh to strong and very gusty during the day, with gales on Atlantic coasts. Rainfall: 2 to 19mm, heaviest at Shannon Airport, 2mm at Casement Aerodrome Temperature: max. 7°C to 12°C, min. 3°C to 6°C, ground temperatures

down to -1°C at Kilkenny

Sunshine: nil to 4 hours, sunniest at Rosslare, nil at Knock Airport

Sunday 2nd: Rain in the north and west spread eastwards during the

morning, giving some heavy falls. Showers followed from the west, affecting all parts during the day. Dry in most parts by evening except for the extreme west. Sunny in the east early in the day, otherwise generally cloudy. Winds were moderate southwesterly at first, turning westerly and increasing to near gale force with stronger gusts.

Rainfall: 3 to 16mm, heaviest at Valentia, 3mm at Rosslare

Temperature: max. 8°C to 14°C, min. 4°C to 8°C, ground temperatures down to -1°C at Claremorris

Sunshine: trace to 5 hours, sunniest at Kilkenny, trace at Knock Airport

Monday 3rd:Showers in western and midland areas during the morning. This

pattern continued through the day, with some showers reaching eastern areas also. Some periods of sunshine in places, particularly the south. Winds were west to southwesterly, moderate to fresh, reaching gale force in many areas. Rainfall: nil to 6mm, heaviest at Belmullet, nil at Rosslare

Temperature: max. 8°C to 13°C, min. 2°C to 9°C, ground temperatures down to -2°C at Johnstown Castle

Sunshine: 1 to 6 hours, sunniest at Cork Airport, 1 hour at Malin Head

Tuesday 4th:Some rain in the west during the morning, generally dry and

overcast elsewhere. More patchy rain and drizzle countrywide during the afternoon. Heavy rain in the west during the evening spread eastwards, clearing the east coast by dawn. Mild throughout the period. Winds were southwesterly, moderate to strong and gusty throughout.

Rainfall: 1 to 9mm, heaviest at Cork Airport, 1mm at Shannon Airport Temperature: max. 13°C to 15°C, min. 6°C to 13°C, no ground frost Sunshine: nil to trace generally, 1 hour at Dublin Airport

Wednesday 5th:Showers in all areas overnight, some heavy and prolonged.

Scattered showers continued through the day, heaviest and most frequent in the west and north, with only a few reaching the southeast. The shower activity decreased and gradually became confined to northern and western parts during the evening. Mild. Sunny spells in the southeast, duller further north. Winds were moderate to fresh southwesterly, near gale force at times.

Rainfall: trace to 11mm, heaviest at Knock Airport, trace at Casement Aerodrome Temperature: max. 11°C to 14°C, min. 7°C to 10°C, no ground frost

Sunshine: <1 to 4 hours, sunniest at Cork Airport, <1 hour at Clones

Thursday 6th:A dry start to the day in most parts. Rain reached the west

coast by early morning and spread quickly eastwards, giving some very heavy falls, clearing the east coast by late morning. Further heavy rain and showers crossed the country from the west during the afternoon. No sunshine, but remaining mild. Winds were southwesterly, moderate to strong and gusty. Rainfall: 8 to 34mm, heaviest at Shannon Airport, 8mm at Malin Head Temperature: max. 13°C to 15°C, min. 5°C to 10°C, no ground frost Sunshine: nil

Friday 7th:Showers overnight in all areas with clear spells also. The showers

continued throughout the day, with sunny spells at times. During the evening and night the showers died out and some ground frost developed in places. Winds were westerly, moderate to strong and gusty, easing by evening. Rainfall: nil to 8mm, heaviest at Belmullet and Shannon Airport, nil at Rosslare Temperature: max. 6°C to 12°C, min. 1°C to 8°C, ground temperatures down to -1°C at Kilkenny and Claremorris

Sunshine: 1 to 4 hours, sunniest at Rosslare, 1 hour at Clones

Saturday 8th:Heavy rain in the southwest moved quickly northeastwards,

reaching all areas by morning. Dull and wet in the northern half of the country. Clearer weather with scattered showers and short sunny spells in Munster and south Leinster in the afternoon, spread to the rest of the country in the evening. Winds were moderate southerly, increasing to fresh and gusty,

veering west to southwesterly, strong to gale force and very gusty. Rainfall: 12 to 29mm, heaviest at Knock Airport, 12mm at Casement Aerodrome Temperature: max. 10°C to 14°C, min. 1°C to 7°C ground temperatures down to -1°C at Kilkenny

Sunshine: nil to 3 hours, sunniest at Cork Airport

Sunday 9th: Early rain in the northwest and midlands moved quickly northeastwards. Heavy showers followed, affecting most parts of the country, although little rain fell in parts of the east, where there was also

most sunshine.Some slight ground frost after dark. Winds were northwesterly,

strong to gale force and very gusty.

Rainfall: 1 to 16mm, heaviest at Knock Airport, 1mm at Dublin Airport Temperature: max. 7°C to 12°C, min. 2°C to 8°C, ground temperatures down to -1°C at Clones

Sunshine: nil to 1 hour generally, 4 hours at Dublin Airport, 2 hours at Valentia

Monday 10th: A few showers in the southwest, otherwise dry with clear skies

in many areas. Sunny periods during the day in most areas, but cloudier in the west. Frost returning after dark to most areas, sharp to severe inland. Winds were variable or northerly, mainly light to moderate.

Rainfall: nil to <1mm generally, >1mm at Valentia

Temperature: max. 7°C to 10°C, min. -2°C to 5°C, ground temperatures below zero at most stations, down to -6°C at Kilkenny

Sunshine: 4 to 7 hours, sunniest at Cork Airport, 4 hours at Belmullet

Tuesday 11th:Very cold overnight. Temperatures rose only slowly in some

inland areas and, apart from patchy light rain in the south, it was a cold and mostly dry day with only short sunny spells in places. Slightly milder along Atlantic coasts. Light southerly or variable winds overnight gradually increased moderate to fresh and gusty and became southeasterly in direction.

Rainfall: nil to trace

Temperature: max. 9°C to 12°C, min. -3°C to 9°C, ground temperatures below zero at most inland stations, down to -6°C at Kilkenny

Sunshine: nil to 2 hours, sunniest at Rosslare

Wednesday 12th:It was a dull day generally with rain in the western half of

the country, while elsewhere there was very little rain and some short sunny spells in the afternoon. The rain was heavy and persistent in the southwest, becoming largely dry later in the evening. Winds were moderate to fresh and gusty, south or southeasterly generally.

Rainfall: nil to <2mm generally, 31mm at Valentia, 6mm at Cork Airport Temperature: max. 10°C to 13°C, min. 8°C to 10°C, no ground frost Sunshine: nil to 2 hours, sunniest at Casement Aerodrome

Thursday 13th:Cloudy and mild during the night with a strong southerly

wind. Continuing mild, breezy and cloudy during the morning. Rain reached the west coast during the morning and moved slowly eastwards, but eastern areas remained dry. Little or no sunshine. Winds were from a southerly direction, fresh to strong in many areas, particularly northern and northwestern regions, up to gale force at times with stronger gusts.

Rainfall: nil to 3mm, heaviest at Belmullet

Temperature: max.10°C to 12°C, min. 4°C to 10°C, no ground frost Sunshine: nil to <1 hour, sunniest at Casement Aerodrome

Friday 14th:Cloudy in the west overnight, with clear periods over the rest of

the country. The day was dry and mostly cloudy. Dry weather continued into the evening, with some ground frost developing in places. Winds were mainly southerly and strong and gusty at times, especially in the north and northwest. Rainfall: nil to trace generally, <1mm at Belmullet

Temperature: max. 8°C to 12°C, min. 1°C to 10°C, ground temperatures down to -3°C at Dublin Airport

Sunshine: nil to <1 hour, sunniest at Mullingar

Saturday 15th:Very cold overnight away from Atlantic coasts, with ground

frost in parts of the east. It was a cold, dry and mostly cloudy day with some patches of mist and little sunshine. Temperatures were generally below normal. Very cold again after dark. Light to moderate southeasterly winds were gusty at times, mainly in Atlantic coastal areas.

Rainfall: nil

Temperature: max. 6°C to 11°C, min. 2°C to 8°C, ground temperatures down to -5°C at Casement Aerodrome

Sunshine: nil to trace generally, <1 hour at Casement Aerodrome

Sunday 16th:It was a dry and cloudy day overall with very little sunshine. Cold with a moderate southeasterly wind giving a significant wind chill. Very cold again after dark, with slight to sharp ground frost in the east, while elsewhere the gusty southeasterly winds prevented any frost.

Rainfall: nil

Temperature: max. 6°C to 10°C, min. 1°C to 8°C, ground temperatures down to -5°C at Casement Aerodrome

Sunshine: nil to <1 hour, sunniest at Belmullet

Monday 17th:Very cold overnight with a sharp to severe ground frost.

Temperatures rose only slowly in the morning and it was a cold, dry day with sunny periods. Some mist patches at times inland. Very cold again after dark with ground frost developing inland. Light to moderate and sometimes gusty southeasterly winds were fresh at times on northern coasts.

Rainfall: nil

Temperature: max. 5°C to 10° min. -2°C to 6°C, ground temperatures below zero at most inland stations, down to -8°C at Casement Aerodrome Sunshine: 5 to 7 hours, sunniest at Mullingar, 5 hours at Clones

Tuesday 18th:Dry overnight with some mist in places and a slight ground

frost in parts. Dry and mostly cloudy throughout the day, apart from the northwest where sunny spells developed. Remaining dry during the evening and night with some ground frost. Winds were light to moderate easterly. Rainfall: nil

Temperature: max. 4°C to 8°C, min. 1°C to 5°C, ground temperatures down to -3°C at Belmullet

Sunshine: nil to 5 hours, sunniest at Belmullet

Wednesday 19th:After a misty start there were long sunny spells almost

everywhere. Cold throughout. Clear skies again after dark with frost returning in the afternoon, particularly in the midlands. Winds were generally light easterly.

Rainfall: nil

Temperature: max. 4°C to 8°C, min -1°C to 5°C, ground temperatures below zero at most inland stations, down to -7°C at Birr

Sunshine: nil to 6 hours, sunniest at Rosslare, nil at Cork Airport

Thursday 20th:Misty during the day with long sunny spells in many places

apart from the east and midlands. Cold throughout. Clear skies again after dark with frost returning during the evening, sharp in the midlands. Misty at times. Winds were light to moderate southeasterly.

Rainfall: nil to trace

Temperature: max. 5°C to 12°C, min. -2°C to 6°C, ground temperatures below zero at most stations, down to -7°C at Belmullet

Sunshine: nil to 5 hours, sunniest at Rosslare

Friday 21st:It was a dry, cold and misty day generally with sunny spells in

places. Afternoon temperatures were a degree or two below normal in most parts. Temperatures fell quickly in north Leinster, Ulster and parts of Connacht after dark, cloudier and milder elsewhere with rain and drizzle affecting Atlantic coasts by evening. Winds were light to moderate, southeasterly in direction. Rainfall: nil to trace

Temperature: max. 3°C to 12°C, min. -6°C to 9°C, ground temperatures below zero at most inland stations, down to -10° at Casement Aerodrome Sunshine: nil to 6 hours, sunniest at Dublin Airport, nil at Cork Airport

Saturday 22nd:A narrow band of heavy rain crossed the country overnight,

clearing the east coast by mid-morning. Generally dry for the rest of the day, apart from some heavy showers in the northwest. Sunny spells everywhere. Winds were light to moderate southeasterly, veering westerly and easing later. Rainfall: 1 to 7mm, heaviest at Belmullet, 1mm at Dublin Airport

Temperature: max. 7°C to 11°C, min. -2°C to 4°C, ground temperatures down to -6°C at Kilkenny

Sunshine: 2 to 6 hours, sunniest at Mullingar, 2 hours at Malin Head

Sunday 23rd: Drizzle and light rain reached the west coast during the late morning and extended slowly eastwards to most parts by midnight. Sunny spells, mainly in the east. Winds were southerly in direction, increasing during the period to reach gale force in most places, with stronger gusts. Rainfall: nil to 14mm, heaviest at Valentia

Temperature: max. 8°C to 13°C, min. -4°C to 7°C, ground temperatures down to -8°C at Kilkenny

Sunshine: nil to 5 hours, sunniest at Dublin Airport, nil at Valentia

Monday 24th:Rain in the west early in the period, spreading eastwards

overnight, heavy in places. Rain along the east coast early in the morning, dry further west with some sunny spells. The afternoon was dry with some spells, mainly in the west. Winds were light and generally variable in direction. Rainfall: trace to 11mm, heaviest at Cork Airport, trace at Belmullet Temperature: max. 8°C to 11°C, min. -1°C to 6°C, ground temperatures down to -7°C at Birr

Sunshine: nil to 4 hours, sunniest at Knock Airport

Tuesday 25th:Around dawn a line of heavy showers moved into the west,

slowly crossing the country through the afternoon and clearing the east coast by early evening. Sunny at first in the east and south, cloudier further west. Winds were light southerly, veering southwesterly and increasing moderate. Rainfall: trace to 7mm, heaviest at Valentia, trace at Johnstown Castle Temperature: max. 6°C to 10°C, min. -3°C to 5°C, ground temperatures

down to -7°C at Birr

Sunshine: trace to 5 hours, sunniest at Dublin Airport, trace at Knock Airport

Wedneday 26th:A dull day generally with some morning sunshine in the east

and southeast. Outbreaks of light rain in many places during the afternoon. Becoming milder during the evening. Some heavy rain in the northwest during the night. Winds were southwesterly, moderate to strong and very gusty. Rainfall: nil to 9mm, heaviest at Knock Airport

Temperature: max. 10°C to 13°C, min. 1°C to 9°C, ground temperatures down to -3°C at Kilkenny

Sunshine: nil to 2 hours, sunniest at Rosslare

Thursday 27th:Showers in the midlands moved eastwards during the early

hours, giving some heavy falls. Rain arrived in the southwest by late morning and spread eastwards, affecting all areas throughout the day. Virtually no sunshine. Winds were southwesterly, moderate to strong and gusty, easing later. Rainfall: 2 to 27 mm, heaviest at Valentia, 2mm at Rosslare

Temperature: max. 10°C to 13°C, min. 6°C to 11°C, no ground frost Sunshine: nil generally, <1 hour at Dublin Airport

Friday 28th:It was a mild, windy day with scattered showers and sunny spells.

Some of the showers were heavy and prolonged. Cold after dark with the showers continuing; some were wintry along Atlantic coasts. Winds were southwesterly, fresh to strong and gusty, up to gale force on exposed coasts. Rainfall: 4 to 18mm, heaviest at Cork Airport, 4mm at Birr

Temperature: max. 10°C to 13°C, min. 1°C to 6°C, ground temperatures down to -1°C at Kilkenny

Sunshine: trace to 4 hours, sunniest at Dublin Airport

Saturday 29th:Very heavy showers overnight, particularly heavy along

Atlantic coasts. A heavy burst of thundery rain affected most of Ulster before dawn. A few sunny spells in most areas. Further showers during the afternoon, most parts dry by evening. Winds were very strong with violent gusts, strongest along the northwest and west coast.

Rainfall: <1 to 10mm, heaviest at Malin Head, <1mm at Cork Airport Temperature: max. 8°C to 10°C, min. 2°C to 5°C, ground temperatures down to -1°C at Birr and Kilkenny

Sunshine: nil to 4 hours, sunniest at Belmullet, nil at Shannon Airport

Sunday 30th:Mild during the day with just the odd shower or a few patches

of light drizzle, but mainly dry. This pattern continued during the evening while remaining very mild. A few brief sunny periods. Winds were mainly southerly in direction, light initially but strengthening during the evening in northwestern regions.

Rainfall: nil to 1mm, heaviest at Belmullet

Temperature: max. 8°C to 12°C, min. 4°C to 7°C, no ground frost Sunshine: nil to 1 hour, sunniest at Shannon Airport, nil at Valentia

Monday 31st:Overnight rain in the west spread gradually eastwards, resulting

in a mild, dull and damp day generally. Just a few sunny spells in the northwest in the afternoon. Continuing mild after dark with the rain and drizzle becoming more patchy. Winds were southerly, moderate and gusty, fresh at times on northwest coasts, easing slightly during the day.

Rainfall: nil to 10mm, heaviest at Belmullet, nil at Dublin Airport Temperature: max. 10°C to 13°C, min. 7°C to 11°C, no ground frost Sunshine: nil to trace

9

Rainfall totals for the month

were very variable across the

country. While it was a wet

month in western areas, totals

were below normal over much of

Leinster, particularly along

eastern and southeastern coasts.

Totals ranged from 51mm at

Dublin (Merrion Square) to

315mm at Maam Valley, Co.

Galway, with percentage of

normal values between 64% at

Rosslare and 173% at Ballygar,

Co. Galway.

The period around the middle of

the month was mostly dry, with

little or no rainfall measured

between the 13th and 21st. Rainfall

was recorded on every other day of

the month, however, and the

number of wetdays during the

month (days with 1mm or more

rainfall) was generally in the normal

range for December of between 15

and 19, although there were fewer

than this in the east and more in

parts of the west. The wettest spell

of the month over most of the

country was between the 6th and

8th, with heavy falls also in many

places on the 27th. Shannon

Airport’s fall of 33.5mm on the 6th

was its highest daily fall for

December since 1975. The highest

daily fall of the month, 44.8mm,

was recorded at Carron, Co. Clare,

on the 27th.

10

RAINFALL

CO. CAVAN

CAVAN (LORETO COLLEGE) 147.3 22.2 27 19 15

CO. CLARE

SHANNON AIRPORT 163.4 165 33.5 6 18 15 CARRON 243.2 148 44.8 27 22 18

CO. CORK

FERMOY (MOORE PARK) 98.8 91 19.7 7 20 17 CORK AIRPORT 134.3 98 20.6 7 19 18 SHERKIN ISLAND 120.9 94 22.2 7 19 18 BALLINCURRIG (PEAFIELD) 129.0 20.4 7 20 17

CO. DONEGAL

MALIN HEAD 109.4 106 19.4 8 20 19 BALLYSHANNON (CATHLEEN’S FALL) 147.1 137 22.3 6 22 19 GLENTIES 193.3 114 20.2 6 22 22

CO. DUBLIN

DUBLIN (PHOENIX PARK) 64.9 79 9.5 1 17 13 DUBLIN AIRPORT 64.1 11.8 7 16 12 CASEMENT AERODROME 67.5 91 10.1 6 16 13 DUBLIN (MERRION SQUARE) 50.9 70 6.4 1 18 13

CO. GALWAY

GALWAY (UNIV.COLL.) 198.6 164 32.2 27 21 18 MAAM VALLEY 315.4 39.4 7 24 23 CONNEMARA NATIONAL PARK 221.2 137 25.1 7 25 25 BALLYGAR 178.0 173 38.5 27 22 17

CO. KERRY

VALENTIA OBSERVATORY 189.5 119 29.6 27 22 21 ARDFERT (LISCAHANE) 134.9 20.7 1 20 18

CO. KILKENNY

KILKENNY 90.7 103 14.7 6 18 12

CO. LIMERICK

MOUNT RUSSELL not available

CO. LOUTH

ARDEE (BOHARNAMOE) 77.0 94 15.2 27 16 11

CO. MAYO

BELMULLET 145.7 122 19.4 6 22 19 STRAIDE 178.6 137 21.4 8 21 18 KNOCK AIRPORT 170.5 19.5 8 21 18

CO. MEATH

WARRENSTOWN 90.8 101 15.8 7 17 12

CO. MONAGHAN

CLONES 111.2 124 17.5 7 18 16

CO. OFFALY

BIRR 107.2 137 18.3 6 17 15 DERRYGREENAGH 105.4 118 18.7 7 18 15

CO. SLIGO

ARDTARMON 130.4 28.9 6 23 18

CO. TIPPERARY

FETHARD (PARSONSHILL) 128.7 18.6 6 18 14

CO. WATERFORD

WATERFORD (TYCOR) 80.6 76 16.9 7 18 15 DUNGARVAN (CARRIGLEA) 110.3 23.0 7 18 16

CO. WESTMEATH

MULLINGAR II 119.5 130 26.7 27 19 16

CO. WEXFORD

JOHNSTOWN CASTLE 88.5 80 16.4 7 18 15 ROSSLARE 62.6 64 14.0 7 15 14 JOHN F. KENNEDY PARK 91.2 87 15.5 7 18 16 CLONROCHE (KNOXTOWN) 105.1 18.2 7 19 15

County/

Station

Total % of

Number of

Amount 1961-90 Most in

Raindays Wetdays

(mm) average a day / date (>0.2mm) (>1mm)

Wetter than normal

generally,

especially in west,

but dry in east

11

RAINFALL

TToottaall rraaiinnffaallll ((m

mm

m))

PPeerrcceennttaaggee ooff nnoorrm

maall rraaiinnffaallll

00 55 1100 1155 2200 2255

11 22 33 44 55 66 77 88 99 1100 1111 1122 1133 1144 1155 1166 1177 1188 1199 2200 2211 2222 2233 2244 2255 2266 2277 2288 2299 3300 3311

Valentia Observatory

Dublin Airport

Clones

Daily 0-24h rainfall values (mm)

December 2007

12

TEMPERATURE

Most of the month was mild with little or no

frost, but there was a short spell of colder

weather between the 19th and 25th, when frost

became widespread. Mean air temperatures for

the month were between one and two degrees

above normal and it was the warmest December

for between 13 and 19 years in parts of Munster

and Connacht. Mean values ranged from 5.2°C at

Derrygreenagh, Co. Offaly, to 9.8°C at Sherkin

Island, Co. Cork.

The early part of the month was exceptionally mild,

with both daytime and nightime temperatures well

above the December normal (see page 3). The highest

value, 15.8°C, was measured at Fermoy (Moorepark),

Co. Cork, on the 6th, the highest December value at

the station since it opened in 1966. There was no air

frost recorded in most coastal locations, while at

many inland stations there were between 2 and 6 air

frosts, compared with the normal range for

December in these areas of between 9 and 11; an

exception was at Derrygreenagh, where as many as 12

air frosts were recorded. The lowest air temperature

of the month, -6.4°C, was measured at Casement

Aerodrome on the 21st, while the lowest grass

minimum value, -10.5°C, was recorded at

Warrenstown, Co. Meath, also on the 21st.

Warmer than normal for

most of month

-55 00 55 1100 1155

11 22 33 44 55 66 77 88 99 1100 1111 1122 1133 1144 1155 1166 1177 1188 1199 2200 2211 2222 2233 2244 2255 2266 2277 2288 2299 3300 3311

00 55 1100 1155 2200

11 22 33 44 55 66 77 88 99 1100 1111 1122 1133 1144 1155 1166 1177 1188 1199 2200 2211 2222 2233 2244 2255 2266 2277 2288 2299 3300 3311

Daily 0-24h maximum temperatures

(°C)

Daily 0-24h minimum temperatures (°C)

‹

Valentia Observatory

Dublin Airport

Clones

‹

Valentia Observatory

Dublin Airport

Clones

M

Meeaann TTeem

mppeerraattuurree

(difference from 1961-90 normals)

SCALE +1.0°C

+1.0°C

-1.0°C

+1.2°C +1.6°C

+1.3°C

+1.3°C +1.1°C

+1.8°C

+1.2°C

+1.5°C +2.1°C

+1.4°C

13

TEMPERATURE

CO. CAVAN

CAVAN (LORETO COLLEGE) 9.6 2.3 6.0 14.4 4 -5.0 21 22 -8.0 21 8 13

CO. CLARE

SHANNON AIRPORT 10.7 5.4 8.1 1.8 15.3 4 0.5 25 -2.3 18 0 8 CARRON 9.8 4.3 7.1 1.9 14.1 4 0.0 25 -6.5 25 0 15

CO. CORK

FERMOY (MOORE PARK) 10.9 5.0 8.0 2.2 15.8 6 -1.7 23 -6.5 23 3 15 CORK AIRPORT 9.9 5.0 7.5 1.5 13.8 6 -0.4 25 -4.8 25 1 5 SHERKIN ISLAND 11.9 7.6 9.8 2.2 14.5 6 1.0 23 -2.2 23 0 4 BALLINCURRIG (PEAFIELD) 10.0 3.7 6.9 14.2 6 -1.8 25 -5.1 11 4 9

CO. DONEGAL

MALIN HEAD 9.5 5.0 7.3 1.0 14.0 4 1.5 19 -4.0 17 0 9 BALLYSHANNON (CATHALEENS FALL) 9.9 4.5 7.2 1.5 14.8 4 0.7 22 0 GLENTIES 9.7 3.6 6.7 1.5 14.7 4 -1.6 19 -3.1 19 2 14

CO. DUBLIN

DUBLIN (PHOENIX PARK) 9.8 2.4 6.1 0.8 14.8 4 -5.2 21 -9.7 21 9 19 DUBLIN AIRPORT 9.7 3.0 6.4 14.7 4 -3.7 22 -8.1 21 6 12 CASEMENT AERODROME 9.9 3.0 6.5 1.2 14.4 6 -6.4 21 -10.2 21 5 12 DUBLIN (MERRION SQUARE) 10.2 4.6 7.4 0.7 15.4 6 -0.7 21 2

CO. GALWAY

GALWAY (UNIV.COLL.) 11.0 4.4 7.7 1.4 15.0 31 -2.0 20 21 -5.5 20 5 10 MAAM VALLEY 11.0 5.6 8.3 15.3 4 0.8 20 -3.3 25 0 5 CONNEMARA NATIONAL PARK 10.5 5.7 8.1 13.9 4 -0.5 19 2 BALLYGAR 9.6 3.3 6.5 14.0 4 -1.6 21 25 -5.0 23 25 5 14

CO. KERRY

VALENTIA OBSERVATORY 12.0 7.4 9.7 2.1 14.6 4 6 1.9 19 -3.5 23 0 4 ARDFERT (LISCAHANE) 11.2 5.8 8.5 1.8 15.1 4 1.5 25 -5.5 25 0 15

CO. KILKENNY

KILKENNY 10.1 2.9 6.5 1.3 15.1 6 -4.3 23 -7.5 23 8 21

CO. LIMERICK

MOUNT RUSSELL 10.4 5.8 8.1 13.3 3 3.4 1 0.8 8 0 0

CO. LOUTH

ARDEE (BOHARNAMOE) 9.5 2.8 6.2 1.2 14.6 6 -4.1 22 8

CO. MAYO

BELMULLET 10.5 5.5 8.0 1.4 14.3 4 -1.4 20 -7.0 20 2 7 STRAIDE 9.8 3.9 6.9 1.2 14.0 4 5 -3.3 25 -7.3 25 4 14 KNOCK AIRPORT 8.2 3.0 5.6 12.7 5 -1.0 21 -1.7 23 5 7

CO. MEATH

WARRENSTOWN 9.5 2.9 6.2 1.2 14.1 5 6 -5.9 21 -10.5 21 6 15

CO. MONAGHAN

CLONES 8.9 2.8 5.9 1.1 14.1 4 -3.1 22 -7.3 21 6 16

CO. OFFALY

BIRR 10.0 3.9 7.0 1.6 15.2 4 -1.1 19 20 -7.6 19 3 14 DERRYGREENAGH 9.3 1.1 5.2 0.6 14.1 4 6 -4.8 22 -9.1 21 12 23

CO. SLIGO

ARDTARMON 9.7 5.0 7.4 13.4 4 1.7 22 25 -2.5 25 0 9

CO. TIPPERARY

FETHARD (PARSONSHILL) 9.4 3.5 6.5 14.0 6 -0.2 25 -2.7 20 25 2 9

CO. WATERFORD

WATERFORD (TYCOR) 11.3 5.0 8.2 2.1 14.4 6 -1.3 25 1 DUNGARVAN (CARRIGLEA) 11.1 5.1 8.1 1.9 15.5 6 -3.0 23 -4.3 23 3 5

CO. WESTMEATH

MULLINGAR II 9.2 2.7 6.0 1.3 13.9 4 -2.3 21 -7.0 21 9 14

CO. WEXFORD

JOHNSTOWN CASTLE 10.2 4.6 7.4 1.3 14.3 2 0.2 11 -4.0 11 20 0 11 ROSSLARE 10.5 5.9 8.2 1.2 13.6 4 5 1.7 23 -1.7 11 0 3 JOHN F. KENNEDY PARK 10.2 4.2 7.2 1.4 14.8 6 -2.1 25 -5.2 25 2 14 CLONROCHE (KNOXTOWN) 9.6 3.3 6.5 15.0 6 -2.9 23 -6.0 23 5 12

Mean/ deviation

Mean Mean from 1961-90 Highest Lowest Lowest Days with max. min. average max./date min./date grass min./date air frost ground frost

County/

Station

14

SUNSHINE

CO. CAVAN

CAVAN (LORETO COLLEGE) 1.19 16 5.1 10 17

CO. CLARE

SHANNON AIRPORT 1.27 89 16 5.7 17

CO. CORK

FERMOY (MOORE PARK) 1.25 95 16 4.2 10

CORK AIRPORT 1.61 103 20 7.0 10

SHERKIN ISLAND 1.78 133 23 6.3 10

BALLINCURRIG (PEAFIELD) 1.63 6.2 10

CO. DONEGAL

MALIN HEAD 1.08 120 15 5.7 21

BALLYSHANNON (CATHALEENS FALL) 1.19 121 16 5.9 17

CO. DUBLIN

DUBLIN AIRPORT 2.27 138 30 6.9 17

CASEMENT AERODROME 1.92 128 25 6.3 17

CO. GALWAY

GALWAY (UNIV.COLL.) 1.42 121 19 6.5 17

CO. KERRY

VALENTIA OBSERVATORY 1.17 100 15 5.2 10

ARDFERT (LISCAHANE) not available

CO. KILKENNY

KILKENNY 1.66 112 22 6.7 10 17

CO. MAYO

BELMULLET 1.35 125 18 6.2 17

KNOCK AIRPORT 1.05 6.4 17

CO. MONAGHAN

CLONES 1.12 99 15 5.7 19

CO. OFFALY

BIRR 1.56 112 20 6.5 17

CO. WATERFORD

DUNGARVAN (CARRIGLEA) 1.39 97 18 6.0 10

CO. WESTMEATH

MULLINGAR II 1.86 122 25 6.9 17

CO. WEXFORD

JOHNSTOWN CASTLE 1.54 102 20 5.5 17

ROSSLARE 2.12 121 27 6.7 10

JOHN F. KENNEDY PARK 1.73 119 22 5.7 10

CLONROCHE (KNOXTOWN) 1.75 6.7 10

Sunnier than normal

almost everywhere

Sunshine totals for the month were above

normal almost everywhere. They ranged

from 33 hours at Knock Airport to 70

hours at Dublin Airport, with percentage

of normal values between 89% of normal

at Shannon Airport and 138% at Dublin

Airport.

Although the period between the 13th and

21st was dry almost everywhere, it was also

dull until the 17th, when most stations

recorded their highest daily totals. The 10th

was also a sunny day generally, especially in

the south; Cork Airport’s value of 7.0 hours

on this day was the highest of the month.

Global solar radiation totals were also higher

than normal in most places, varying between

98% of normal at Birr and 127% at Dublin

Airport.

Daily mean % of % of Most in (hours/day) average possible a day/date

County/

Station

00 22 44 66 88

11 22 33 44 55 66 77 88 99 1100 1111 1122 1133 1144 1155 1166 1177 1188 1199 2200 2211 2222 2233 2244 2255 2266 2277 2288 2299 3300 3311

Daily sunshine values (hours)

Valentia Observatory

Dublin Airport

Clones

TToottaall SSuunnsshhiinnee

(difference from 1961-90 normals)

SCALE 150%

50%

99%

89%

128% 122%

125%

110%

120%

103% 100%

121% 112%

15

WORLD WEATHER

Global weather

highlights of

the month

December 2007

DECEMBER RAINFALL

(percentage of

1961-1990 normal)

DECEMBER MEAN TEMPERATURE

(difference from

1961-1990 normal)

Data supplied by NOAA Climate Prediction Centre, US Department of Commerce

%

200

150

125

100

75

50

0

+5

+3

+1

-1

-3

-5

°C

A severe winter storm affected much of the U.S. during the week of the 10th. Freezing rain and snow left a covering of thick ice in many midwestern states, causing the deaths of 36 people and leaving more than 800,000 homes without power. The same system moved towards the northeast, bringing heavy snow; Boston received 25cm of snow on the 13th, more than the city typically gets during the entire month of December.

Tropical storm Olga developed in the western Atlantic as a sub-tropical storm on the 10th, after the official end of the Atlantic hurricane season. It moved westwards along the northern coast of Puerto Rico with sustained winds of 75 km/h, producing torrential rainfall of over 200mm in the interior of the island. The storm reached its peak intensity of 93km/h on the 11th, just before making landfall in the eastern coast of the Dominican Republic. Here, the release of water from the Tavera Dam for fear of its collapse inundated seven towns. In total, Olga affected more than 34,000 people, killing 20 and damaging nearly 7,000 homes.

According to the World Meteorological Organisation, sea levels continue to rise at rates substantially above the average for the 20th century of about 1.7mm per year. Satellite measurements show that since 1993, the global-averaged sea level has been rising at about 3mm per year, while the 2007 level is about 20cm higher than the 1870 estimate.