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The weather in March was mostly influenced by troughs of low pressure systems and the easterly trade winds. On the 1st, a frontal system lingered just south of Fiji until
the 3rd drifting northwards over the group on the 4th. Occa-
sional showers were experienced over the southern and eastern parts of the country. On the 5th, a trough moved
over the country from the north and directed a strong east-
erly wind flow together with continuous rain over the whole country until the 9th. On the 10th, a ridge of high pressure extended onto the
group from the south and displaced the trough back north-
wards, keeping the trade easterlies over Fiji until the 12th. This prevailing condition brought trade showers mainly
over the eastern parts and interior of the main islands while the northern and eastern parts of Fiji experienced occasion-
al showers. A moist easterly wind flow prevailed over Fiji for a couple
of days thereon. However, on the 15th, the trough that was
displaced to the northeast of the group moved back closer to Fiji and remained slow moving just northeast of Vanua
Levu. Meanwhile, a frontal system slowly approached Fiji from the south and moved over Kadavu on the 17th. An
intense high pressure system to the south eventually
*Previously known as the Fiji Islands Weather Summary and Monthly Weather Summary
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Fiji Climate Summary
March 2017
Issued: April 6, 2017 Since : August 1980* Volume 38 : Issue 03
pushed the front over the group causing rain and thunder-storms and strong southeast winds over the group. The
front gradually weakened on the 19th. A tropical disturb-ance developed along a pre-frontal trough on the 20th
which gradually moved southeastwards towards Tonga.
Cloud bands associated with the trough to the northeast of the group brought more rain over Fiji, especially over Va-
nua Levu. The continuous heavy rain resulted in flooding
in most parts of the Northern Division over this period. The rain eased over the group on the 22nd. Later on the 23rd, another trough to the west of Fiji slowly
approached the group and eventually moved over the coun-
try on the 25th. The trough affected most parts of the coun-try till the 26th with occasional showers being observed. On
the 27th, this trough weakened and moved north, away from Fiji allowing the moist easterlies to settle yet again
over the group. Generally fine conditions prevailed over
Fiji till month end even though a weak trough affected the eastern part of the country on the 28th and 29th. Rotuma’s weather was mainly affected by a series of troughs and the trade easterly wind flow during the month.
2. WEATHER PATTERNS
1. IN BRIEF ENSO neutral conditions persisted during March 2017. However, certain aspects of the atmosphere displayed some
weak La Niña characteristics. Rainfall during the month was average to above average
over most parts of the country, with 17 out of the 25 sta-tions recording average rainfall and six above average rain-
fall. The exception to this were Lakeba and Ono-i-Lau in
the Lau Group, where below average rainfall was received. The maximum air temperatures were generally normal to above normal during the month, with nine out of the 21 sta-
tions recording anomalies ≥0.5˚C, nine within ±0.5˚C and
three ≤-0.5˚C. The minimum temperatures were normal to above normal across the country, with 13 out of the 21 sta-
tions recording anomalies ≥0.5˚C and eight within ±0.5˚C.
The mean maximum air temperatures during the month ranged from 29.6°C to 32.5°C in the coastal areas of Fiji,
while Nadarivatu and Monasavu in the highlands recorded 25.6°C and 25.8°C, respectively. However, daily daytime
air temperatures as high as 35.2°C was recorded at Naco-
colevu on the 12th, followed by Rarawai Mill with 35.0°C on the same day. The mean minimum air temperatures ranged from 22.5°C to 25.2°C in the coastal areas, whilst at Nadarivatu and
Monasavu in the highlands, it was 19.6°C and 20.0°C, re-spectively. Most of the stations registered the coolest night-time temperatures between 17th and 20th, with Nadarivatu
recording 17.2°C on the 17th, followed by Monasavu with 17.5°C on the 20th.
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3. RAINFALL
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
Normal: Long term average from 1971 to 2000 Average: Rainfall between 80 to 119% Well Below Average: Rainfall less than 40% of normal Above Average: Rainfall between 120 to 199% Below Average: Rainfall between 40 to 79% Well Above Average: Rainfall greater than or equal to 200% of normal Rain Day: Rainfall ≥ 0.1mm
Figure 1
Rainfall during March was generally average to above av-
erage over the Fiji Group. The exceptions to this were
Lakeba and Ono-i-Lau where below average was recorded. Seventeen sites recorded average rainfall, six above aver-
age rainfall and two below average rainfall. Notable rainfall episode was experienced during the first
week of March with all the stations recording significant amounts of rainfall. Majority of the stations, particularly
the Western Division recorded their 24-hour maximum rainfall during this period. Significant maximum 24-hour rainfall greater than 100mm was recorded at a number of sites during the month with
202.6mm recorded at Tokotoko on the 16th, followed by 148.5mm at Nadarivatu, 132.5mm at Tavua and 122.4mm
at Rarawai Mill all on the 6th, 118.9mm at Laucala Bay on
the 23rd, 104.0mm at Korolevu on the 6th, 102.5mm at Ro-tuma on the 19th, 101.0mm at Lomaivuna on the 2nd and
100.5mm at Yaqara on the 6th. Ono-i-Lau received the least rainfall during the month with
143.4mm, followed by Lakeba with 175.1mm and Yasawa
with 196.6mm. On the other hand, Tokotoko was the wet-test station with 623.3mm followed by Nabouwalu with
590.6mm, Nadarivatu with 539.0mm and Nadi Airport with 509.8mm. The number of rain days (rainfall ≥0.1mm) during the month ranged from 16 to 31 days. Monasavu recorded the
greatest number of rainy days with rainfall recorded on eve-
ry day of the month, followed by 26 days at Seaqaqa, and 25 days at Udu Point, Dreketi, Koronivia and Nabouwalu. No new rainfall record was established during March.
3
Note: All comparisons in this summary are with respect to “Climatic Normals”. This is defined to be the average climate con-
dition over a 30-year period. Fiji uses 1971-2000 period as its “climatic normal” period, unless otherwise stated.
5. WATER LEVELS DURING MARCH 2017
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
4. AIR TEMPERATURES
A. Maximum Daytime Air Temperatures Generally normal to above normal daytime temperatures were recorded during the month. Nine out of the twenty
one sites recorded anomalies within ±0.5˚C, 9 sites record-ed anomalies ≥0.5˚C and 3 sites recorded temperature
anomalies of ≤-0.5˚C (Table 2 & Figures 2-5). The warmest days on average was at Rarawai Mill with
32.5˚C, followed by Labasa Airport with 32.1˚C and Na-
cocolevu and Rotuma with both 32.0˚C. On the other hand, Nadarivatu recorded the coolest maximum temperature on
average, with 25.6˚C, followed by Monasavu with 25.8˚C. The highest daily daytime temperature of 35.2˚C was rec-
orded at Rarawai Mill on the 12th, followed by 35.0˚C at Nacocolevu on 12th and 34.2˚C at Labasa Airport on the
29th. On the other hand, the lowest daytime temperature
was recorded at Nadarivatu with 21.8˚C on the 5th, fol-lowed by Monasavu with 22.1˚C on the 21st. The greatest mean monthly anomaly of +1.4˚C was ob-
served at Rotuma, followed by +1.2˚C at Nabouwalu,
+0.9˚C at Nacocolevu and Vunisea, and +0.8˚C Viwa and at Penang Mill. On the other hand, the greatest negative
anomaly of –0.9˚C was recorded Tokotoko, followed by –0.6˚C at Udu Point. No new maximum temperature record was set in March 2017.
B. Minimum Night-time Air Temperatures The night-time temperatures were normal to above normal, with 8 sites recording anomalies within ±0.5˚C and 13 sites
recorded anomalies ≥0.5˚C (Table 2 & Figures 2-5).
The coolest night on average was at Nadarivatu with 19.6˚C, followed by Monasavu with 20.0˚C and Labasa
Airport with 22.5˚C. In contrast, the warmest average night
-time temperature of 25.2˚C was observed at Rotuma, Viwa and Udu Point, followed by 25.0˚C at Matuku. The coolest daily night-time temperature was registered at Nadarivatu with 17.2˚C on the 17th, followed by 17.5˚C at
Monasavu, 19.0˚C at Rarawai Mill, 19.3˚C at Nacocolevu and 19.9˚C at Nausori Airport , all on the 20th. On the contrary, warmest night was observed at Viwa, Ro-tuma and Matuku with 27.0˚C on the 31st, 30th and 12th,
respectively, followed by 26.9˚C at Udu Point and Nabouwalu on 10th and 12th, respectively, 26.8˚C at Laucala
Bay on 16th and 26.5˚C at Matei Airfield and Vunisea on
10th and 14th, respectively. The greatest positive mean monthly night-time air tempera-
ture anomaly of +1.4˚C was recorded at Tokotoko, fol-lowed by +1.2˚C at Vunisea and +0.9˚C at Laucala Bay and
Savusavu Airfield. No significant negative departure was recorded.
Water levels in all major rivers were mostly average to above average. Sigatoka, Labasa and Rakiraki recorded average levels, Rewa and Navua recorded average to above average whilst Tuva recorded above average. The maximum water level was recorded at Rewa bridge station (2.14m), while Navolau station recorded second highest water level (1.94m), followed by Sabata station (1.74m) in the Rewa and Navua catchment. The least monthly water
level was recorded at Yavuna (0.18m), followed by Wairikicake recorded (0.33m).
4
TABLE 2. DAILY CLIMATE REPORTING SITES: SUMMARY FOR MARCH 2017
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
RAINFALL AIR TEMPERATURES SUNSHINE TOTAL RAIN MAX. AVERAGE DAILY EXTREME TOTAL * DAYS FALL MAX. # MIN. # MAX. MIN. * MM % + MM ON C C C C C ON C ON HRS % NADI AIRPORT 510 150 22 76 4 30.9 -0.4 23.5 0.7 33.6 13 21.5 20 177 92 SUVA/LAUCALA BAY 383 102 23 119 23 30.5 -0.4 24.8 0.9 32.4 9 23.4 1 117 69 NACOCOLEVU 246 93 18 57 4 32.0 0.9 22.9 0.4 35.2 12 19.3 20 175 115 ROTUMA 328 90 20 103 19 32.0 1.4 25.2 0.5 33.3 15 22.2 14 188 114 VIWA 286 118 16 70 17 31.8 0.8 25.2 0.0 33.1 8 23.5 23 UDU POINT 296 93 25 63 11 30.1 -0.6 25.2 0.8 31.3 28 23.4 22 SAVUSAVU AIRFIELD 270 95 20 59 19 30.1 -0.5 24.5 0.9 32.6 29 23.3 19 LABASA AIRFIELD 437 117 20 61 7 32.1 0.6 22.5 0.2 34.2 29 21.5 29 NABOUWALU 591 176 25 91 25 31.3 1.2 24.7 0.4 33.6 9 23.0 25 KORONIVIA 374 97 25 74 3 30.8 0.3 23.5 0.6 32.3 9 20.0 26 NAUSORI AIRPORT 313 82 22 62 8 30.6 0.1 23.9 0.7 32.3 27 19.9 20 NAVUA/TOKOTOKO 624 151 28 203 16 30.1 -0.9 23.0 1.4 32.0 9 20.1 8 MONASAVU 497 80 31 72 2 25.8 0.4 20.0 0.8 28.6 9 17.5 20 LAUTOKA AES 370 120 18 78 5 31.2 0.2 24.0 0.2 32.8 31 20.8 25 BA/RARAWAI MILL 430 118 16 122 6 32.5 0.5 22.9 0.6 35.0 12 19.0 20 PENANG MILL 440 104 23 214 5 31.3 0.8 24.5 0.7 32.7 27 23.3 6 MATEI AIRFIELD 336 88 24 81 19 30.8 0.5 23.9 -0.3 32.0 2 22.0 19 VANUABALAVU STATION CLOSED LAKEBA 175 60 19 45 3 30.7 0.4 24.6 0.6 32.8 11 23.1 6 LEVUKA AWS U/S VUNISEA 303 100 17 96 2 30.9 0.9 24.7 1.2 32.9 4 23.0 22 MATUKU 241 95 17 72 1 30.1 -0.3 25.0 0.4 32.0 9 22.0 18 ONO-I-LAU 143 57 16 58 1 29.6 0.3 24.3 -0.1 31.7 9 21.5 18 DREKETI 428 134 25 79 4 SEAQAQA 466 116 26 92 7 YASAWA-I-RARA 227 83 14 51 5 DOBUILEVU 326 76 22 59 2 YAQARA 253 72 13 101 6 TEMPERATURE( C)HUMIDITY WIND SUN RAD DRY WET RH% VP %OF MJ/ MEAN (AVERAGE AT 9AM) KT POS SQ.M NADI AIRPORT 27.2 28.1 24.9 77 29.0 7.9 45 15.6 SUVA/LAUCALA BAY 27.7 27.7 25.4 83 30.7 30 17.5 NACOCOLEVU 27.5 28.5 25.8 80 31.0 45 20 ROTUMA 28.6 29.7 27.6 85 35.2 2.6 51 21 VIWA 28.5 29.2 26.6 81 32.7 5.5 UDU POINT 27.6 28.0 26.0 85 32.2 5.5 SAVUSAVU AIRFIELD 27.3 28.0 25.7 83 31.3 LABASA AIRFIELD 27.3 28.5 25.8 80 31.1 NABOUWALU 28.0 28.4 26.1 83 32.0 7.9 KORONIVIA 27.1 27.8 25.6 83 31.1 NAUSORI AIRPORT 27.3 27.5 25.4 84 30.7 2.7 NAVUA/TOKOTOKO 26.6 26.5 25.0 88 30.4 MONASAVU 22.9 22.5 21.3 90 24.5 LAUTOKA AES 27.6 29.4 25.9 75 30.7 BA/RARAWAI MILL 27.7 28.1 25.5 81 30.6 PENANG MILL 27.9 27.9 25.5 83 30.9 MATEI AIRFIELD 27.3 28.3 26.1 83 32.0 VANUABALAVU STATION CLOSED LAKEBA 27.6 28.6 26.0 81 31.5 6.0 LEVUKA AWS U/S VUNISEA 27.8 27.8 25.7 84 31.5 5.5 MATUKU 27.5 28.1 25.3 79 30.0 4.8 ONO-I-LAU 27.0 27.9 24.9 78 29.1 8.0 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 LONG-TERM AVERAGES. BLUE FONT– MISSING RECORDS OF LESS THAN OR EQUAL TO 5 DAYS.
5
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
Figure 2
Figure 3
Figure 4
6
observed on the 2nd , 5th and 21st with nil hours of bright sunshine. The total monthly bright sunshine at Nacocolevu was
174.7 hours, with a daily mean of 5.6 hours. The station’s
highest daily bright sunshine of 10.5 hours was recorded on the 14th, followed by 10.0 hours on the 19th. Rotuma recorded 188.4 hours of total monthly bright sun-shine, with a mean of 6.3 hours/day. The longest duration
of bright sunshine was 10.4 hours on the 2nd, followed by 10.1 hours on the 28th. Overcast condition was observed on
the 19th with nil hours of bright sunshine.
The Outgoing Longwave Radiation (OLR) map on Figure 11 shows normal cloud cover within our region during the
month. Consequently, Nacocolevu, Rotuma, Nadi Airport, and Laucala Bay recorded 115%, 114%, 92% and 69% of
the normal bright sunshine hours during the month, respec-
tively (Table 2). Nadi Airport recorded 177.2 hours of the total bright sun-
shine, with a mean of 5.7 hours/day. The station recorded more than 10 hours of sunshine from 12th to 15th. On the
other hand, overcast conditions were observed on the 5th and 25th, with nil hours of bright sunshine. Laucala Bay (Suva) recorded 116.8 hours of total monthly bright sunshine, with a mean of 3.8 hours/day. The longest
duration of bright sunshine was 10.3 hours on the 14th, followed by 8.2 hours on the 27th. Overcast condition was
6. RELATIVE HUMIDITY AT 0900HOURS
7. SUNSHINE
The 9am average relative humidity (RH) ranged from 75% to 90% during the month (Table 2). Generally normal RH
was observed during the month with anomalies ranging within ±4%. The Western Division stations recorded daily average RH
values between 75% and 83%. The RH departures during
the month ranged from –2.0% to +1.3%. Negative depar-tures of –2.0%, –1.9% and –1.1% was recorded at Naco-
colevu, Lautoka Mill and Rarawai Mill, respectively, while positive departure of +1.3% was observed at Viwa.
The Central Division stations recorded daily average RH values between 83% and 88%. Generally normal RH were
observed throughout the Division, with anomalies within
±1% except at Tokotoko, where the departure was +4%.
Northern Division stations recorded daily average RH from 80% to 85%. Positive RH anomalies of +3.5%,
+2.7%, +1.9% and +1.1% was observed at Udu Point, Nabouwalu, Matei Airfield and Savusavu Airfield, corre-
spondingly. Labasa Airport was the lone site to record neg-
ative departure of –2.8%.
The mean monthly RH in the Eastern Division ranged from
78% to 84%. Positive departures of +2.7% and +1.9% was observed at Vunisea and Lakeba, respectively, while
anomaly of –1.6% was observed at Ono-I-Lau. The daily average RH at Monasavu was 90% with anomaly
of +2.7% , while at Rotuma it was 85% with anomaly of +4%.
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
Figure 5
7
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
8. WIND SUMMARY
Figure 6(b) Surface Wind Speed for Nadi Airport, Fiji. (WMO 91680 Lat
17°°°°45'35"South Long 177°°°°26'42"East Height above MSL 22m) Figure 6(a) Surface Wind Direction for Nadi Airport, Fiji. (WMO 91680
Lat 17°°°°45'35"South Long 177°°°°26'42"East Height above MSL 22m)
Figure 7(b) Surface Wind Speed for Nausori Airport, Fiji. (WMO 91683
Lat 18°°°°02'47"South Long 178°°°°33'33"East Height above MSL 3m) Figure 7(a) Surface Wind Direction for Nausori Airport, Fiji. (WMO
91683 Lat 18°°°°02'47"South Long 178°°°°33'33"East Height above MSL 3m)
by light breeze accounting for 18.5% of the occasions and gentle breeze with 14.9% (Figure 7(b). The wind anomalies map on the NOAA website show per-
sistence of easterly winds of up to 2m/s 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
The 10-minute average wind statistics recorded every three hours at Nadi Airport in March showed that easterly winds
were predominant, accounting for 37.1% of the total obser-vations, followed by westerly with 16.1% and north-easterly with 14.1% (Figure 6(a)). Calm conditions were
recorded on 6.0% 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 60.5%
of the three hourly observations, followed by easterly winds with 14.9% and south easterly winds with 11.7%
(Figure 7(a)). Mostly calm winds were experienced at
Nausori Airport with 60.5% of the observations, followed
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10. RADIATION
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
9. EVAPORATION
Figure 10: SSTs were near nor-
mal in the Fiji region
during March 2017
(base period: 1981-2010). http://www.esrl.noaa.gov/
psd/map/clim/sst.shtml
The total monthly raised pan evaporation at Nadi Airport was 145.0mm, while Laucala Bay recorded 88.6mm. Nadi Air-port recorded the highest daily evaporation of 11.6mm on the 7th. Laucala Bay registered the highest of 8.0mm on the
15th.
11. SEA SURFACE TEMPERATURE (SST)
Figure 9: The mean daily solar radiation at Nadi
Airport during
March 2017 was 15.6MJ/m2, com-
pared to 18.9MJ/m2
over 30 year average (1971-2000).
Figure 8
9
14. WIND ANOMALIES
13. SEA LEVEL
12. CLOUD COVER
Fiji Climate Summary - March 2017 Volume 38 : Issue 03
Figure 13: Reanalysis data show south easterly wind
anomalies of up to 2m/
s persisted in the Fiji region during March
2017 (Fiji: ~17ºS,
180º) (base period: 1981-2010). http://
www.esrl.noaa.gov/
psd/map/images/rnl/
sfcwnd_30a.rnl.gif
Figure 12: Below normal sea level continues to per-
sist in the Fiji waters,
with –5 to –10cm anomalies (base peri-
od: 1981-2010). http://
www.cpc.ncep.noaa.g
ov/products/
analysis_monitoring/
ocean/
weeklyenso_clim_81-10/wksl_anm.gif
Figure 11: OLR anomalies indi-cate presence of nor-
mal to 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
