FIJI
METEOROLOGICAL
SERVICE
Private Mail Bag (NAP0351)
Nadi Airport, Fiji
Ph: +679 6724888, Fax: +679
6724050
Email: [email protected]
Also online at h p://
www.met.gov.
Issued: October 7, 2016
1.0
Fiji Climate Summary
ISO 9001:2008
certified Climate
Services
September 2016
Since : August 1980*
Volume 37 : Issue 09
IN BRIEF
September was considerably drier than normal, with all of
the rainfall reporting stations observing well below average
rainfall during the month, except for Rotuma.
New daily day time temperature records were established at
Laucala Bay (Suva) and Levuka on the 27th and 29th respectively.
All climate monitoring stations recorded less than 40% of
normal September rainfall with no rainfall recorded at Levuka and Nacocolevu. Significant number of stations received less than 20% of normal rainfall.
The cooler nights were generally experienced from the 6th
to 12th with the lowest night-time temperature of 13.0˚C,
recorded at Monasavu on the 22nd .
In contrast, Rotuma recorded 159% of normal rainfall this
month largely from the South Pacific Convergence Zone
and a trough of low pressure.
New monthly rainfall records were established at Nacocolevu and Levuka replacing previous records set in 2003.
Unusually hot days were recorded at Labasa Airport, Penang, Rarawai and Levuka with daytime temperatures exceeding 33.5˚C on 29th and 30th respectively (Table 2).
2.0
Sunshine was below average at Rotuma, near average at
Nacocolevu and Laucala Bay and above average at Nadi
Airport.
The 9am average relative humidity (RH) ranged from 62%
to 90% during the month (Table 2).
Radiation at Nadi Airport was normal compared to 30 year
average.
WEATHER PATTERNS
September was dominated by the broad southeasterly
winds, transient trough of low pressure and semi permanent
high pressure systems.
rection. The cool southwesterly winds coupled with the
minimal cloud cover at night caused the overnight temperature to drop.
From the 1st till 5th, a semi-permanent high to the south of
Fiji was directing a broad southeasterly wind flow over the
group. Showers, which were heavy at times was mostly
observed towards the windward side of the islands. Matei
Airport recorded 43.8mm on the 1st which was also the
highest 24 hour rainfall recoded for the month.
Monasavu recorded an overnight minimum of 13.0˚Con the
22nd which was also the lowest nigh-time temperature recorded for the month. The front weakened and cleared Fiji
later on the 23rd as the southeast winds temporarily prevailed over Fiji.
th
The southeast winds eventually weakened on the 6 as a
frontal system approached Fiji from the southwest. The
front moved onto Fiji overnight on the 7th and eventually
cleared the group on the 9th.
Another ridge extended onto Fiji on the 10th and directed a
very stable southeasterly wind flow over Fiji which prevailed till the 20th. With the exception of coastal showers
which occurred in the Eastern part of the islands, fine
weather prevailed over most places during this period.
The ridge receded overnight on 20th as another front approached Fiji from the southwest. As the frontal system
moved closer to Fiji, the winds turned to southwesterly di-
On the 26th, a trough of low pressure approached Fiji from
the southwest and moved onto the group on the 28th and
quickly cleared Fiji on the 29th. Cloudy skies with brief
showers was experienced over parts of Fiji.
Rotuma was affected by the South Pacific Convergence
Zone (SPCZ) and a trough of low pressure. Rotuma experienced some rain in the first week from the SPCZ. On the
11th, a trough of low pressure approached the Island from
the north and brought much needed rain. Rotuma received
82.6mm of rain from this trough and this was the most significant rainfall recorded for the month.
Overnight temperatures were below 23˚Cthroughout the
month at Rotuma.
*Previously known as the Fiji Islands Weather Summary and Monthly Weather Summary
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Fiji Climate Summary - September 2016
3.0
Volume 37 : Issue 09
RAINFALL
September was considerably drier than normal, with all
rainfall recording stations reporting well below average
rainfall, except for Rotuma, which recorded above average
rainfall. (Figures 1-4 & Table 2).
There were two new monthly rainfall records established
during the month. Nacocolevu and Levuka received no
rainfall for whole of September replacing the previous record of 4.6mm and 10.8mm, both established in 2003.
There was one major rainfall episode between the 6th to the
15th, which brought rain mostly in the Northern and Central
Divisions. This lead to more than 50% of the stations recording their maximum 24 hour rainfall during this period.
Koronivia recorded the highest number of rain days
(rainfall ≥0.1mm), with 27 days, followed by 20 days at
Rotuma, 14 days at Monasavu, 12 days at Nausori Airport
and Matei Airfield with 11days at Laucala Bay and Navua.
The highest monthly rainfall of 379.3mm was recorded at
Rotuma followed by Nasinu with 96.0mm, Koro Island
with 92.5mm, Monasavu with 78.0mm and Laucala Bay
(Suva) with 56.9mm. The rest of the stations recorded less
than 50mm of monthly rainfall.
On the three month (3months) timescale, Matei Airport,
Udu Point and Rotuma are in meteorological drought
whilst Dobuilevu, Ono-i-Lau and Penang are in meteorological drought warning stage and Lakeba in meteorological drought watch.
Significant twenty four (24) hour rainfall of 82.6mm was
observed at Rotuma on the 10th, followed by 34.1mm at
Laucala Bay on the 6th, 50.0mm at Nasinu and 43.5mm at
Koro Island on the 6th. Other stations recorded less than
30.0mm of twenty four hour rainfall.
Figure 1
Normal: Long term average from 1971 to 2000
Well Below Average: Rainfall less than 40% of normal
Below Average: Rainfall between 40 to 79%
Rain Day: Rainfall ≥ 0.1mm
Average: Rainfall between 80 to 119%
Above Average: Rainfall between 120 to 199%
Well Above Average: Rainfall greater than or equal to 200% of normal
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Fiji Climate Summary - September 2016
4.0
Volume 37 : Issue 09
AIR TEMPERATURES
A.
Maximum Daytime Air Temperatures
The average day time temperatures varied across the country, with 10 out of the 21 stations recording anomalies ≥
±0.5˚C, 11 within ≥0.6˚C and 1 ≤ -0.6˚C (Table 2 & Figures 2-5).
B.
Minimum Night-time Air Temperatures
The average night-time temperatures at various climate
stations also varied around average with 10 out of the 21
stations recording anomalies ± 0.˚C, 5 within ≥ +0.6 and 6
within ≤ -0.6. (Table 2 & Figures 2-5).
The warmest days on average was at Rarawai Mill (Ba)
with 31.2˚C, followed by Rotuma with 30.5˚C and Viwa
with 29.5˚C. On the other hand, the coolest maximum temperature on average was registered at Monasavu with
22.6˚C.
The coolest nights on average was at Monasavu with
15.4˚C, followed by 17.6˚C at Labasa Airport and 19.0˚C
at Nacocolevu. Conversely, the warmest night on average
was experienced at Rotuma with 24.4˚C, followed by Viwa
with 22.8˚C and Udu Point with 22.4˚C.
On the daily temperatures, more than 80% of the stations
recorded their daily maximum temperature between the
26th to 30th. The highest daily maximum temperature of
33.9˚Cwas recorded at Rarawai Mill (Ba) on the 30th, followed by 33.7˚Cat Levuka on the 29th, which also happened to be a new daily day time September record for
Levuka.
Significantly cool conditions were experienced on the 6th,
11th to 12th and during the last week of the month, with the
lowest night-time temperature of 13.0˚C, recorded at
Monasavu on the 22nd , followed by 14.6˚Cat Labasa Airport and 14.9˚Cat Rotuma, both on the 6th.
On the other hand, the coolest daily day time temperature
was recorded at Monasavu with 16.8˚C on the 01st, followed by Nausori Airport with 22.1˚C on the 11th, and Ono
-i-lau with 22.4˚C on the 11th.
The greatest positive mean monthly day time temperature
departure from the normal was recorded at Levuka, with
+1.4°C, followed by +1.3˚Cat Viwa and +1.2˚Cat Rotuma.
On the other hand, the most significant negative anomaly
was observed at Udu Point with –0.9˚C.
On the other hand, Rotuma recorded night-time temperature as high as 26.5˚C on the 20th, followed by 25.1˚C at
Savusavu Airport on the 30th and 25.0˚C on the 28th at
Viwa.
The most notable positive mean monthly night-time air
temperature departure from the normal of +1.7˚C was recorded at Navua, +1.0˚C at Vunisea (Kadavu) and Laucala
Bay (Suva).
No new night-time temperature record was established this
the month.
There were three daily day time temperature records established during the month. Levuka recorded a new high of
33.7˚C on the 29th, 32.5˚Cat Laucala Bay (Suva) on the
27th and 32.2˚C at Nausori Airport on the 29th.
TABLE 1. CLIMATE RECORDS ESTABLISHED IN SEPTEMBER 2016
Element
Station
Observed
(record)
On
Rank
Previous
(record)
Year
Records
Began
Monthly Total Rainfall
Levuka
0mm
-
New Low
10.8mm
2003
1984
Monthly Total Rainfall
Nacocolevu
0mm
-
New Low
4.6mm
2003
1926
Daily Maximum Temperature
Laucala Bay, Suva
32.5°C
27th /
New High
28th
32.1°C
1943/
2014
1942
Daily Maximum Temperature
Levuka
33.7°C
29th
New High
33.0°C
2002
1984
Daily Maximum Temperature
Nausori Airport
32.2°C
27th
New High
31.8°C
1986
1956
Note: All comparisons in this summary are with respect to “Climatic Normals”. This is defined to be the average
climate condition over a 30-year period. Fiji uses 1971-2000 period as its “climatic normal” period, unless otherwise stated.
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Fiji Climate Summary - September 2016
Volume 37 : Issue 09
TABLE 2. DAILY CLIMATE REPORTING SITES: SUMMARY FOR SEPTEMBER 2016
RAINFALL
TOTAL RAIN MAX.
* DAYS FALL
MM
% +
MM ON
NADI AIRPORT
SUVA/LAUCALA BAY
NACOCOLEVU
ROTUMA
VIWA
UDU POINT
SAVUSAVU AIRFIELD
LABASA AIRFIELD
NABOUWALU
KORONIVIA
NAUSORI AIRPORT
NAVUA/TOKOTOKO
MONASAVU
LAUTOKA AES
BA/RARAWAI MILL
PENANG MILL
MATEI AIRFIELD
VANUABALAVU
LAKEBA
LEVUKA
VUNISEA
MATUKU
ONO-I-LAU
7 10 2
57 32 11
0
0 0
379 159 20
4
6 1
42 38 7
44 33 7
8 11 2
6
34
0
83
4
30
28
6
AIR TEMPERATURES
SUNSHINE
AVERAGE DAILY
EXTREME
TOTAL
MAX. #
MIN. #
MAX.
MIN.
*
C
C
C
C
C ON
C ON HRS
%
27 29.0 -0.3 19.7 0.4
6 27.4 0.2 22.0 1.0
0 28.2 0.3 19.0 0.6
10 30.5 1.2 24.4 0.3
27 29.5 1.3 22.8 0.1
11 27.7 -0.9 22.4 -0.1
28 27.0 -0.3 22.1 0.9
11 31.3 1.1 17.6 -1.7
MISSING OBSERVATION
6 27.4 0.5 20.0 0.2
12 26.9 0.3 20.2 0.2
19 26.9 -0.5 19.8 1.4
7 22.6 0.3 15.4 -0.5
9 29.3 0.6 20.2 -0.5
27 31.2 0.8
4 29.1 1.1 20.4 -0.8
11 28.0 0.5 21.2 -0.6
50 29 27
22
26 16 12
7
41 18 11
9
78 29 14
17
3
4 1
3
12 16 3
10
1
1 2
1
14
9 12
5
STATION CLOSED
3
3 2
3 12
0
0 0
0 0
22 16 8
8 6
5
5 5
2 14
24 22 6
17 27
27.9
28.5
27.3
26.7
26.3
1.0
1.4
1.2
0.3
0.9
20.7
21.1
20.8
19.3
19.9
-0.7
-0.7
1.0
-1.5
-0.5
32.6
32.5
31.3
32.0
32.7
30.0
30.8
33.9
30
27
29
24
27
27
28
29
16.3
19.6
14.9
18.5
20.5
18.5
19.9
14.6
18
6
6
30
24
12
6
6
31.0
32.2
31.5
28.1
31.6
33.9
33.7
30.7
27
27
27
26
27
30
30
28
17.2 6
17.2 6
16.5 6
13.0 22
17.5 19
31.3
33.7
30.3
29.3
30.7
28
29
27
27
26
17.5
18.8
17.6
15.3
18.0
245 116
142 104
164 96
156 87
15.7 23
18.4 4
26
12
23
11
11
TEMPERATURE( C)HUMIDITY WIND SUN RAD
DRY WET RH% VP
%OF MJ/
MEAN
(AVERAGE AT 9AM)
KT POS SQ.M
NADI AIRPORT
24.4 25.9 21.0 63 21.1 7.0 71 19.2
SUVA/LAUCALA BAY
24.7 25.0 21.5 72 22.9
41 17.5
NACOCOLEVU
23.6 24.4 21.4 76 23.2
48 17
ROTUMA
27.4 27.9 26.8 91 34.3 4.3 45 18
VIWA
26.1 27.1 23.3 72 25.8 7.0
UDU POINT
25.0 25.7 22.7 76 25.2 7.9
SAVUSAVU AIRFIELD 24.6 25.4 21.6 75 24.6
LABASA AIRFIELD
24.4 27.2 22.8 67 24.4
NABOUWALU
MISSING OBSERVATION
KORONIVIA
23.7 25.0 21.8 74 23.6
NAUSORI AIRPORT
23.5 24.4 21.4 76 23.3 4.3
NAVUA/TOKOTOKO
23.4 23.9 21.4 79 23.5
MONASAVU
19.0 18.7 17.0 84 18.0
LAUTOKA AES
24.7 26.7 21.9 64 22.6
BA/RARAWAI MILL
26.5 21.4 62 21.5
PENANG MILL
24.7 26.2 22.0 68 23.3
MATEI AIRFIELD
24.6 25.9 22.7 75 25.2
VANUABALAVU
STATION CLOSED
LAKEBA
24.3 25.9 22.5 74 24.7 6.8
LEVUKA
24.8 25.3
VUNISEA
24.0 24.4 21.6 75 23.4 10.7
MATUKU
23.0 24.6 20.8 70 21.7 11.8
ONO-I-LAU
23.1 24.4 20.7 71 21.6 11.2
MEAN TEMPERATURE IS (MAX+MIN)/2;
WIND IS MEAN SPEED AT 06,12,18,24 HOURS.
$ :SOLAR RADIATION CALCULATED FROM SUNSHINE DURATION. # :DEPARTURE FROM LONG-TERM
AVERAGES (1971-2000). + :NUMBER OF DAYS WITH 0.1 MM OR MORE RAIN. * :PERCENT OF LONGTERM AVERAGES. MISSING DATA WITH LESS THAN FIVE DAYS.
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Fiji Climate Summary - September 2016
Volume 37 : Issue 09
Figure 2
Figure 3
Figure 4
5
Fiji Climate Summary - September 2016
Volume 37 : Issue 09
Figure 5
5.0
RELATIVE HUMIDITY AT 0900HOURS
The 9am average relative humidity (RH) ranged from 62%
to 90% during the month (Table 2).
The Western Division stations recorded daily average RH
values less than 65%. All of the stations recorded negative
mean monthly RH departures from the normal with the
greatest negative departure observed at Penang Mill
(Rakiraki) with -12.9%, followed by –7.9% at Rarawai
(Ba) and –5% at Lautoka Mill.
The Central Division stations recorded daily average RH
values between 72% and 79%. Negative anomalies were
also recorded at the stations, with the negative departure
of –6.8% recorded at Laucala Bay (Suva), followed by
–5% at Navua, while Nausori and Koronivia recorded departures of –5%.
6.0
Northern Division stations recorded daily average RH
from 86% to 94%. Generally negative mean monthly RH
departures from the normal were registered across the Division, with the most significant anomaly of –4.5% recorded at Labasa Airport, followed by –3.7% at Savusavu Airport and –2.6% at Matei Airport.
The mean monthly RH in the Eastern Division ranged from
70% to 75%. Negative anomalies from normal were recorded throughout the division, with the most significant
departure of –3.4% at Matuku, followed by –2.8% at Ono-i
-Lau and –1.3% at Vunisea (Kadavu).
The daily average RH at Monasavu was 84% and 91% at
Rotuma.
SUNSHINE
Rotuma, Nacocolevu, Laucala Bay and Nadi Airport recorded 87%, 96%, 104% and 116% of the normal bright
sunshine hours during the month, respectively (Table 2).
Nadi Airport recorded 245.0 hours of total bright sunshine,
with a mean of 8.2 hours/day. The longest duration of
bright sunshine at the station was 11.2 hours on the 22nd.
On the other hand, extended period of overcast conditions
persisted on the 12th, with no bright sunshine.
Laucala Bay recorded 141.7 hours of total monthly bright
sunshine, with a mean of 4.7 hours/day. No bright sunshine was recorded on a number of days due to overcast
conditions on the 9th and from 11th to 13th. On the other
hand, the longest duration of bright sunshine was 10.8
hours on the 22nd.
The total monthly bright sunshine hours at Nacocolevu was
164.3 hours, with a daily mean of 5.5 hours. The station’s
highest daily bright sunshine of 9.1 hours was recorded on
the 29th , with no overcast conditions recorded at the station.
Rotuma recorded 155.7 hours of total bright sunshine, with
a mean of 5.2 hours/day. The longest duration of bright
sunshine hours at the station was 10.8 hours on the 27th,
while overcast conditions were recorded on the 2nd , 9th and
11th. More than 10.0hours of sunshine were also recorded
on the 5th, 26th and 28th.
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Fiji Climate Summary - September 2016
7.0
Volume 37 : Issue 09
WIND SUMMARY
The 10-minute average wind statistics recorded every three
hours at Nadi Airport in September showed that easterly
winds were predominant, accounting for 43.8% of the total
observations, followed by westerly with 17.9%, southeast
with 13.8%, and northeast with 6.7% (Figure 6(a)). Calm
conditions were recorded on 6.3% of the occasions. The 10
-minute average wind speeds were light to gentle breeze in
strength (Figure 6(b)).
At Nausori Airport, calm conditions accounted for 31.3%
of the occasion followed by southeast winds with 30.4%,
winds from east with 16.7% and from south with 12.9%
(Figure 7(a)). The wind speeds ranged from light to moderate in strength (Figure 7(b)).
The wind anomalies map on the NOAA website suggest
north-westerly wind anomalies of 1.5m/s persisted in the
Fiji region (Figure 13)
Note:
light air: 1-3 knots, light breeze: 4–6 knots, gentle breeze: 7-10 knots,
moderate breeze: 11-16 knots, fresh breeze: 17-21 knots, strong breeze: 22
-27knots, near gale: 28-33 knots; gale: 34-40 knots; strong gale: 41-47
knots
Figure 6(a) Surface Wind Direction for Nadi Airport, Fiji. (WMO 91680 Figure 6(b) Surface Wind Speed for Nadi Airport, Fiji. (WMO 91680 Lat
Lat 17°
°45'35"South Long 177°
°26'42"East Height above MSL 22m)
17°
°45'35"South Long 177°
°26'42"East Height above MSL 22m)
Figure 7(a) Surface Wind Direction for Nausori Airport, Fiji. (WMO Figure 7(b) Surface Wind Speed for Nausori Airport, Fiji. (WMO 91683
91683 Lat 18°
°02'47"South Long 178°
°33'33"East Height above MSL 3m) Lat 18°
°02'47"South Long 178°
°33'33"East Height above MSL 3m)
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Fiji Climate Summary - September 2016
8.0
Volume 37 : Issue 09
EVAPORATION
Figure 8
The total monthly raised pan evaporation at Nadi Airport was 162.4mm, while Laucala Bay recorded 113.0mm. Nadi Airport’s highest daily evaporation was 7.6mm on the 2nd and 4th, while Laucala Bay recorded the highest of 7.4mm on the
15th.
9.0
RADIATION
Figure 9:
The mean daily solar
radiation at Nadi Airport during September
2016 was 19.2MJ/m2
compared to 19.1MJ/m2
over 30 year average.
SEA SURFACE TEMPERATURE (SST)
Figure 10:
SST anomaly within the
Fiji region were around
normal in September 2016
(base period: 1981-2010).
http://www.esrl.noaa.gov/
psd/map/clim/sst.shtml
8
Fiji Climate Summary - September 2016
Volume 37 : Issue 09
CLOUD COVER
Figure 11:
OLR anomalies indicate
presence
of
slightly
above normal cloud cover
in the Fiji region (Fiji:
~17ºS, 180º) (base period:
1981-2010).
http://www.esrl.noaa.gov/
psd/map/clim/olr.shtml
SEA LEVEL
Figure 12:
Negative sea level anomalies continues to persist
in the Fiji waters, ranging
from –5 to –10cm (base
period: 1981-2010).
http://
www.cpc.ncep.noaa.gov/
products/
analysis_monitoring/
ocean/
weeklyenso_clim_81-10/
wksl_anm.gif
WIND ANOMALIES
Figure 13:
Reanalysis data suggest
north-westerly
wind
anomalies of 1.5m/s persisted in the Fiji region
(Fiji: ~17ºS, 180º) (base
period: 1981-2010).
http://www.esrl.noaa.gov/
psd/map/images/rnl/
sfcwnd_30a.rnl.gif
This Summary is prepared as
soon as ENSO, climate and oceanographic data is received from recording stations around Fiji and Meteorological Agencies around the World.
Delays in data collection, communication and processing occasionally arise. While every effort is made to verify observational data, the Fiji Meteorological Service does not guarantee the accuracy and reliability of the analyses presented, and accepts no liability for any losses incurred
through the use of this information and its contents. The information can be freely disseminated provided the source is acknowledged.
For further information, contact: The Director of Meteorology, Fiji Meteorological Service, Private Mail Bag NAP0351, Nadi Airport,
9