Government of Nepal Ministry of Science, Technology and Environment

Department of Hydrology and Meteorology

Babarmahal, Kathmandu, Nepal

PRELIMINARY WEATHER SUMMARY OF NEPAL

January 2013

MAIN HIGHLIGHT

Large parts of the country remained warmer than normal. Western parts received more rainfall than the

eastern parts.

Fog and cold wave gripped the southern plains (Terai) of Nepal until third week with spatial and temporal

variation in severity (Images 1 & 2).

SYNOPTIC SEQUENCES:

Weather systems and rainfall activities over Nepal in January were mainly affected by western disturbances

(WDs) as upper air troughs and upper air cyclonic circulations (UACCs). Though many western disturbances as

upper air troughs influenced north Pakistan & adjoining Jammu & Kashmir and western Himalayan region,

only one of them in third week influenced the weather systems over Nepal and produced some rainfall

mainly in the western parts of the country which contributed to the overall January rainfall.

Along with WD, three UACCs in the first three weeks also affected the weather over Nepal.

PRECIPITATION DISTRIBUTION:

Western half of the country received more rainfall than eastern half. Least rainfall (below 20 mm) was

received in Eastern Region (ER), Central Region (CR) and some parts in Western Region (WR) and Mid

Western Region (MWR) (Figure 1). Most parts of the ER, CR and southern parts of WR and (MWR) remained

drier than normal. Bajura recorded the highest 24 hour rainfall of 76.6 mm on 19th January with the highest

monthly total rainfall of 135.0 mm. Jumla received the highest percent of rainfall 352.8 % (100.3mm). Rainfall

was received only on 18th and 19th of the month.

TEMPERATURE PATTERN:

Large parts of the country remained warmer than normal during this month. Mean temperature was

however below 1 °C in most of southern parts of Tarai region because of the cold wave condition associated

with fog, whereas northern parts of the country remained warmer than normal along with some of the

isolated patches in the southern parts of WR and MWR (Figure 4) warming by more than 1 °C.Tansen, in the

WR recorded the highest positive temperature anomaly of 1.9 °C whereas Taulihawa, in the WR recorded the

highest negative temperature anomaly of -2.6 °C. The mean temperature in January varied between less than

6 °C in the northern parts of Mid-western region and adjoining parts of Western Region to above 18.0 °C in

the southeastern parts of Eastern Region in Dharan bazar. (Figure 3, Table 1). The highest maximum

temperature of 31.2 °C was recorded in Surkhet on 22nd January while the lowest minimum temperature of –

10.1 °C was recorded in Jumla on 8th January. The intermittent fog episode which started from the mid of the

second week of December 2012 in the southern Terai plains lasted until third week of January 2013 (Figure 5,

Image 1, Image 2). However, fog episode was variable on tempo-spatial scale. Due to the cold wave condition

associated with the fog, the day time maximum temperature in the affected areas plummeted down by more

than 10 °C and even up to 13 °C (on 8th January in Simara) than normal (Figure 6). Minimum temperature also

plummeted upto -6.9°C than normal in Biratnagar on 9th January. Fog covered the whole Terai Region on 8th

January. Fog episode was relatively more intense this year than in 2012.

The preliminary weather data for January 2012 is presented in Table 1.

Image 1 Image 2

Image 1: Visible band of Kalpana Satellite showing Indian subcontinent on date 8th January 2013, 4:30z

Image 2: Visible band of Kalpana Satellite showing north east sector of Indian subcontinent on date 8th

January 2013, 4:30z

Remarks: Normal Rainfall (Gray colour) = 100 ± 10 %

Normal Temperature (Gray colour) = 0 ± 0.2 °C

27

28

29

30

Dadeldhura

Dhangadhi

Jumla

Surkhet

Nepalgunj Dang

Bhairahawa

Pokhara

Simara

Kathmandu

Okhaldhunga

Dhankuta

Biratnagar

Taplejung

Dipayal

-5 20 45 70 95 120

Bajura

0

80 81 82 83 84 85 86 87 88

27

28

29

30

Dadeldhura

Dhangadhi

Jumla

Surkhet

Nepalgunj Dang

Bhairahawa

Pokhara

Simara

Kathmandu

Okhaldhunga

Dhankuta

Biratnagar

Taplejung

Dipayal

-2.8 -1.8 -0.8 -0.2 0.2 1.2

27

28

29

30

Dadeldhura

Dhangadhi

Jumla

Surkhet

Nepalgunj Dang

Bhairahawa

Pokhara

Simara

Kathmandu

Okhaldhunga

Dhankuta

Biratnagar

Taplejung

Dipayal

-20 50 90 100 110 190 260 3300

Fig.1: Total Precipitation (mm) January 2013

Fig.2: Percentage of Normal Precipitation(%) January 2013

Fig.3: MeanTemperature(°C) January 2013

Fig.4:Departure of Mean Temperature from Normal(°C) January 2013

Eastern

Central

Western

Mid-western

Far-western

27

28

29

30

Dadeldhura

Dhangadhi

Jumla

Surkhet

Nepalgunj Dang

Bhairahawa

Pokhara

Simara

Kathmandu

Okhaldhunga

Dhankuta

Biratnagar

Taplejung

Dipayal

4 6 8 10 12 14 16 18

Figure 5: Temperature anomaly during January, 2013 in (a) Dhangadhi (b) Bhairahawa (c) Simara and (d)

Biratnagar Airport.

Temperature Monitoring in Terai Region

-14

-12

-10

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Maximum temperature anomaly Dhangadhi

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Minimum temperature anomaly

-14

-12

-10

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Maximum temperature anomaly Simara

-10

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Minimum temperature anomaly Simara

-12

-10

-8

-6

-4

-2

0

2

4

6

8

1-J

an

5-J

an

9-J

an

13-J

an

17-J

an

21-J

an

25-J

an

29-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Maximum temperature anomaly Biratnagar

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Minimum temperature anomaly Biratnagar

Dhangadhi

-16

-14

-12

-10

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Maximum temperature anomaly Bhairahawa

-8

-6

-4

-2

0

2

4

6

8

1-J

an

6-J

an

11-J

an

16-J

an

21-J

an

26-J

an

31-J

an

Tem

pera

ture

anom

aly

(°C

)

Day (Month)

Daily Minimum temperature anomaly Bhairahawa

Table 1

≥ 1

.0 m

m

≥ 1

0.0

mm

≥ 2

5.0

mm

≥ 5

0.0

mm

Avera

ge M

ax

Dep

art

ure

fro

m t

he

no

rmal

Hig

hest

Max &

Date

Avera

ge M

in

Dep

art

ure

fro

m t

he

no

rmal

Lo

west

Min

& D

ate

Mo

nth

ly M

ean

Dep

art

ure

fro

m t

he

no

rmal

DADELDHURA 113.2 264.4 2 2 2 1 68.3/19 15.3 1.3 18.2/30 3.0 -1.1 0/7 10.0 1.0

SUNDARPUR 58.5 208.1 2 2 2 0 29.5/18 M M M M M M M M

DARCHULA 77.2 166.5 4 2 2 0 40.6/19 20.0 1.1 23.5/31 3.7 -1.0 0.6/8 12.8 0.9

CHAINPUR(WEST) 116.7 237.1 2 2 2 1 72.2/19 19.0 0.7 22.2/13 1.7 -1.7 -1.2/8 11.5 0.7

BAJURA 135.0 233.6 2 2 2 2 76.6/19 16.0 - 18.5/15 1.3 1.3 -1.5/8 10.0 -

DHANGADHI 53.4 187.9 2 2 1 0 33.1/19 17.6 -3.2 25.7/17 7.0 -0.1 0.5/10 11.9 -2.1

DIPAYAL (DOTI) 98.6 256.2 3 2 2 1 54.2/19 22.1 -0.1 26.4/17 4.2 -0.6 0.2/8 14.6 1.0

JUMLA 100.3 352.8 2 2 2 1 51.2/18 14.7 0.8 19.5/1 -6.3 -1.3 -10.1/8 5.2 0.8

SURKHET 44.1 128.4 2 2 1 0 28.7/19 22.7 2.9 31.2/22 4.0 -1.4 -0.7/9 14.3 1.7

NEPALGUNJ AIRPORT 3.6 12.3 1 0 0 3.6/18 18.3 -1.4 26.2/30 6.8 -0.9 -0.3/9 12.3 -1.4

LIBANG GAUN 5.3 17.8 2 0 0 0 3.1/18 17.7 - 21.5/17 7.4 7.4 3.5/1 14.1 -

CHAUR JHARI TAR 37.0 110.2 2 1 1 0 32.4/19 17.8 -2.8 21.2/31 5.4 0.1 2.4/10 11.6 -1.3

GHORAI (DANG) 8.6 30.8 2 0 0 0 4.6/18 21.1 1.1 25.5/17 4.8 -1.1 1/8 14.1 1.1

JOMSOM 10.5 142.8 1 1 0 0 10.5/19 10.4 -0.3 14.5/11 -2.3 -0.1 -6.4/10 4.9 0.7

BAGLUNG M M M M M M M 19.6 -1.9 22.1/29 4.8 -1.7 1.7/11 13.4 -0.6

BENI BAZAR 27.9 185.0 2 1 0 0 22.2/19 20.4 0.2 23/20 5.9 -0.7 3/10 14.5 1.1

KUSHMA M M M M M M M 22.1 1.2 24.5/17 4.7 -2.7 0.5/3 14.2 0.1

TANSEN M M M M M M M 19.5 1.9 22.5/30 7.2 -0.5 3.8/10 14.5 1.9

BHAIRHAWA AIRPORT 17.4 98.2 2 1 0 0 15/19 17.9 -3.1 24.9/18 7.6 -1.2 2.8/10 13.0 -2.0

TAULIHAWA M M M M M M M 17.9 -3.8 25.2/31 6.9 -2.0 1.7/10 12.7 -2.6

TAMGHAS M M M M M M M 14.7 -0.5 20/17 4.0 -0.6 1.5/10 10.1 0.2

KHUDI BAZAR 28.9 112.6 3 1 0 0 21.8/19 21.1 1.0 24.5/29 6.4 -0.2 2.5/6 15.2 1.8

POKHARA AIRPORT 17.6 76.1 3 1 0 0 14.6/19 20.1 0.4 22.8/29 6.2 -0.9 2.4/10 13.9 0.5

SYANGJA 22.8 103.8 3 1 0 0 19.5/19 20.4 0.3 23.4/31 4.8 -1.3 0.5/10 13.3 0.2

GORKHA 13.8 62.6 1 1 0 0 13.5/19 21.2 2.1 24.2/29 6.7 -1.6 2/9 14.6 1.0

LUMLE 37.8 116.5 2 1 1 0 34.4/19 M M M M M M M M

KHAIRINI TAR 14.9 74.6 2 1 0 0 11/19 22.5 1.1 25.9/31 6.3 -2.0 1.4/10 13.9 -0.9

SIMARA AIRPORT 4.2 29.1 1 0 0 0 4.2/19 20.6 -0.9 27.5/4 5.6 -2.2 2/6 12.6 -2.1

GODAVARI 16.3 85.7 1 1 0 0 16.3/19 17.6 2.3 20.8/17 0.5 -2.7 -3.1/9 10.1 0.8

KATHMANDU AIRPORT 11.5 80.0 1 1 0 0 11.3/19 18.9 -0.2 25/31 1.6 -0.8 -2/9 11.2 -1.7

JIRI 10.5 89.9 1 1 0 0 10.5/19 14.5 0.3 19.2/17 -2.2 -0.6 -5.7/8 6.8 0.4

SINDHULI GADHI* 2.2 13.2 1 0 0 0 2.2/19 23.1 1.8 25.5/30 6.5 -1.4 4/26 15.1 0.4

JANAKPUR AIRPORT 10.5 89.9 1 1 0 0 10.5/19 19.9 -2.3 27/2 7.3 -1.8 0.5/9 13.2 -2.4

OKHALDHUNGA 7.2 61.7 1 0 0 0 7.2/19 16.7 1.7 20.2/18 2.6 -3.1 -1.5/8 10.0 -0.4

LAHAN M M M M M M M 21.9 -0.5 26.5/21 7.2 -2.2 2.2/9 14.7 -1.2

RAJBIRAJ M M M M M M M 20.1 -3.8 25/2 8.4 -1.4 2/9 14.8 -2.0

CHAINPUR (EAST) 4.2 34.6 1 0 0 0 4.2/19 19.3 1.0 21/30 4.7 -2.3 2.2/9 12.5 -0.2

DHANKUTA 8.6 114.7 1 0 0 0 8.6/19 21.1 3.3 24.2/18 5.7 -1.4 2.5/9 14.0 1.6

DHARAN BAZAR 5.5 43.8 1 0 0 0 5.5/19 22.5 - 26.8/18 11.2 - 4.1/9 18.3 -

BIRATNAGAR AIRPORT 18.0 153.4 1 1 0 0 18/19 22.0 -0.7 27.6/2 7.5 -1.4 2/9 15.0 -0.8

TAPLEJUNG 7.7 41.8 1 0 0 0 7.7/19 15.8 1.8 22.2/12 2.6 -1.6 0/7 9.5 0.4

PHIDIM (PANCHTHER) M M M M M M M 22.0 2.6 24.7/18 6.6 -0.1 4.3/9 14.8 1.7

Remarks: -- = Normal not available M = Data not available * = Rainfall station

PRELIMINARY MONTHLY WEATHER DATA

Month,year

Rainfall recorded on a day is the total 24 hour rainfall from the previous day 8:45 am till 8:45 am of that day.

TEMPERATURE

No. of Rainy Days

24h

rs E

xtr

em

e R

ain

fall

& D

ate

Maximum ( °C ) Minimum ( °C ) Mean ( °C )

Stations

PRECIPITATION

To

tal (m

m)

% o

f N

orm

al