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Government of Pakistan
Pakistan Meteorological Department
Islamabad
Monthly Weather Report
January 2020
Director General
Pakistan Meteorological Department
Prepared by: National Weather Forecasting Center, Pakistan Meteorological
Department, Islamabad
1
Contents
1. SUMMARY ................................................................................................................................... 3
2. INTRODUCTION........................................................................................................................... 4
3. FIRST SPELL ............................................................................................................................... 5
4. SECOND SPELL ........................................................................................................................... 7
5. THIRD SPELL .............................................................................................................................. 9
5 FOURTH SPELL ......................................................................................................................... 10
5 ACCUMULATED RAINFALL ...................................................................................................... 12
6. RAINFALL DEPARTURE ............................................................................................................ 14
7. FORECAST VALIDATION ............................................................................................................ 15
8. TEMPERATURE ......................................................................................................................... 16
9. FOG SITUATION ........................................................................................................................ 17
10. SNOW .................................................................................................................................. 17
11. DROUGHT CONDITION .......................................................................................................... 19
12. ACKNOWLEDGMENT ............................................................................................................ 20
13. REFERENCES ......................................................................................................................... 20
ANNEX I ........................................................................................................................................... 21
2
List of Figures Figure 1 Synoptic situation 4th to 7th January 2020. Shaded portion represents the geopotential
height pattern at 500 hPa, solid line represents the geopotential height pattern at 850 hPa, while
arrows indicate 850 hPa winds. ......................................................................................................... 5
Figure 2 Rainfall (mm) distribution during 5th to 8th January 2020. ................................................. 6
Figure 3 Synoptic situation from 11th to 14th January 2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds. ........................................................................................ 7
Figure 4 Rainfall (mm) distribution during 12th to 14th January 2020. ............................................. 8
Figure 5 Synoptic situation from 19th to 22nd January,2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds. ........................................................................................ 9
Figure 6 Rainfall (mm) distribution during 19th to 22nd January,2020. .......................................... 10
Figure 7 Synoptic situation from 24th to 29th January,2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds. ...................................................................................... 11
Figure 8 Rainfall (mm) distribution during 25th to 29th January, 2020 ........................................... 12
Figure 9 Rainfall (mm) distribution during JA. .............................................................................. 13
Figure 10 Rainfall departure in January 2020 ................................................................................. 14
Figure 11 Spatial distribution of rainfall (mm) departure in January 2020 .................................... 14
Figure 12 Temperature comparison between normal and January 2020 minimum temperatures. . 16
Figure 13 Mean temperature anomaly in January w.r.t 1981-2010 ................................................ 16
Figure 14 Number of foggy days in January 2020.......................................................................... 17
Figure 15 Snowfall (ft) in Jan 2020 ................................................................................................ 18
Figure 16 Drought outlook during the month of January. .............................................................. 19
List of Tables Table 1: Rainfall Departure............................................................................................................... 4
Table 2 Forecast verification contingency table ............................................................................. 15
Table 3 Percentage accuracy of each spell ...................................................................................... 15
3
1. SUMMARY
Following are the main features of January 2020:
1. In January 2020 area weighted rainfall of the country remained above normal by 133%.
2. On regional basis area weighted rainfall was above normal in Khyber Pakhtunkhwa by 62%,
Punjab 186%, Azad Jammu and Kashmir 48%, Sindh 99%, Gilgit Baltistan 94%, and in
Balochistan 182%.
3. Foggy conditions were more prolonged in Upper & Central Punjab than other parts of the
country.
4. On all Pakistan basis near normal average minimum temperatures were recorded.
5. Mountainous areas of Pakistan received good snowfall.
4
2. INTRODUCTION
January is the coldest month in Pakistan with mean minimum temperature varying from -8.2℃
in Skardu to 13.8℃ in Jiwani. Normal area weighted rainfall in January for Pakistan is 19 mm,
For Azad Jammu and Kashmir it is 52.6 mm, Gilgit Baltistan 17.6 mm, Khyber Pakhtunkhwa
45.5 mm, Sindh 2.8 mm, Punjab 15.6 mm and Balochistan 18.1 mm. In January 2020 lowest
minimum temperature was recorded in Skardu (-21.6℃) on 19th of January. Highest accumulated
precipitation during the whole month was recorded in Malamjaba (223 mm). While highest
amount of rainfall during 24 hours was recoded in Rawalakot (86.6 mm) on 14th of January. In
January 2020 area weighted rainfall in the country remained above normal by 133 %. On regional
basis rainfall remained on higher side of above normal in Sindh 99%, Punjab 186%, Balochistan
182%, Khyber Pakhtunkhwa -62%, Azad Jammu & Kashmir 48% and Gilgit Baltistan 94%. The
details are given in table 1.
Table 1: Rainfall Departure
Four rainy spells entered Pakistan during this month. Their detail is appended below.
5
3. FIRST SPELL
Synoptic situation during the first spell of January as obtained by NCEP/NCAR reanalysis dataset
(Kalnay 1996) is shown in figure 1. During the first spell a western disturbance is seen that is
affecting western and some upper parts of the country.
Figure 1 Synoptic situation 4th to 7th January 2020. Shaded portion represents the geopotential
height pattern at 500 hPa, solid line represents the geopotential height pattern at 850 hPa, while
arrows indicate 850 hPa winds.
6
Spatial distribution from 5th to 7th January shows that most parts of the country receives rainfall but
some heavy downpours occurred in Balochistan, the upper parts also receive significant amount of
rainfall.
Figure 2 Rainfall (mm) distribution during 5th to 8th January 2020.
7
4. SECOND SPELL
Synoptic situation during the first spell from 11th to 14th January,2020 figure 3. A moderate western
disturbance can be seen in the charts and a component of moisture is available from the Arabian Sea.
Figure 3 Synoptic situation from 11th to 14th January 2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds.
8
Spatial distribution of rainfall from 12th to 14th January 2020 is shown in figure 4. It shows that most
parts of Pakistan receive rainfall with moderate to heavy falls Upper kp, some parts of South
Balochistan and Kashmir .
Figure 4 Rainfall (mm) distribution during 12th to 14th January 2020.
9
5. THIRD SPELL
The synoptic situation during the third spell from 19th to 22nd January,2020 is shown in figure 5. A
shallow western disturbance can be seen at the end of this decade.
Figure 5 Synoptic situation from 19th to 22nd January,2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds.
10
Figure 6 represents the spatial distribution of rainfall during the Third Spell from 19th to 22nd
January,2020. During this most parts of the country remained dry however some upper parts of the
country receive isolated moderate rainfall. and some traces in the western parts of Balochistan.
Figure 6 Rainfall (mm) distribution during 19th to 22nd January,2020.
5 FOURTH SPELL
The synoptic situation during the Fourth spell from 24th to 29th January,2020 is shown in figure 7. A
shallow western disturbance can be seen at the end of this decade
11
Figure 7 Synoptic situation from 24th to 29th January,2020. Shaded portion represents the
geopotential height pattern at 500 hPa, solid line represents the geopotential height pattern at 850
hPa, while arrows indicate 850 hPa winds.
12
Figure 8 shows spatial distribution during the fourth spell from 25th to 29th January, 2020.
Figure 8 Rainfall (mm) distribution during 25th to 29th January, 2020
5 ACCUMULATED RAINFALL
In January the whole country receive rainfall. The Upper KP, Kashmir and Islamabad receive very
heavy showers while Balochistan and some upper parts in the country also receive heavy rainfalls.
in the month. Details of rainfall are appended in annexure I.
13
Figure 9 Rainfall (mm) distribution during JA.
14
6. RAINFALL DEPARTURE
During this month area weighted rainfall of the country remained above normal 133%. On regional
basis rainfall was above normal in Sindh 99%, Punjab 186%, Gilgit Baltistan 94%, Balochistan
182%, Azad Jammu and Kashmir 48%, and Khyber Pakhtunkhwa 62% as represented in figure 10.
The Figure 11 shows the spatial distribution of rainfall departure in the month of December with
respect to the base period of 1961-2010. The spatial distribution of rainfall departure is shown in
figure 9 (CDPC 2019).
Figure 10 Rainfall departure in January 2020
Figure 11 Spatial distribution of rainfall (mm) departure in January 2020
15
7. FORECAST VALIDATION
An attempt is made to substantiate the accuracy of precipitation forecasts issued in January. This is
done by using the contingency table 1, for each of the three decades. This table is used to find out
the level of agreement between forecast and actual observation. The difference between forecast and
observation is the error. The lower the errors, the greater the accuracy.
Table 2 Forecast verification contingency table
Observed
Yes No Total
Fo
reca
st
Yes Hits False Alarms Forecast Yes
No Misses Correct Negatives Forecast No
Total Observed Yes Observed No Total
Hits means when the precipitation was forecasted and it occurred. Miss is used when the precipitation
was not forecasted and it occurred. False alarm means when the precipitation was forecasted and it
did not occur. Correct negatives are when the precipitation was not forecasted and also it did not
happen. Accuracy of forecast is calculated by using formula in equation 1. Table 2 describes the
accuracy in each of the spells
𝐴𝑐𝑐𝑢𝑟𝑎𝑐𝑦 = 𝐻𝑖𝑡𝑠 + 𝑐𝑜𝑟𝑟𝑒𝑐𝑡 𝑛𝑒𝑔𝑎𝑡𝑖𝑣𝑒𝑠/𝑇𝑜𝑡𝑎𝑙 (1)
Table 3 Percentage accuracy of each spell
Rainfall spells Percentage accuracy
First Decade 91.4
Second Decade 93.1
Third Decade 87.5
Average 90.74
16
8. TEMPERATURE
Figure 12 represents the comparison of January 2020 and mean minimum temperatures over the
country. During the month of January below normal minimum temperatures were recorded in
Pakistan. In all the provinces the below normal minimum temperatures were observed.
Figure 12 Temperature comparison between normal and January 2020 minimum temperatures.
Figure 13 Mean temperature anomaly in January w.r.t 1981-2010
-4
-2
0
2
4
6
8
10
Pakistan Punjab Kashmir-GB KP Sindh Balochistan
Jan_2020 Normal
Min Temperature comparison
17
9. FOG SITUATION
A graph representing number of foggy days is shown in figure 14 (FFD 2020). Hafizabad and
Narowal recorded maximum twenty-two foggy days in this month. In this month fog was more
persistent in upper Punjab as compared to other parts of the country as indicated by figure 14.
Some stations from upper Sindh also reported fog during the period.
Figure 14 Number of foggy days in January 2020
10. SNOW
In January good snowfall was reported from the mountainous areas of Pakistan. Murree received
almost 3.71 ft of snowfall. While maximum snowfall of almost 9.20 ft among 24 reporting
stations of PMD, was reported from Malamjaba. Snowfall in feet of some selected stations during
Jan 2020 is shown in figure 15.
18
Figure 15 Snowfall (ft) in Jan 2020
19
11. DROUGHT CONDITION
According to the latest drought analysis done by National Drought Monitoring Center of PMD,
Slightly Wet conditions prevailed over northern parts of the country and parts of southwestern parts
of Balochistan and some parts of Southeastern Sindh. Drought analysis results using different indices
are represented in figure 16.
Figure 16 Drought outlook during the month of January.
20
12. ACKNOWLEDGMENT
This work is the combined effort of all the forecasting team. Special thanks to Mr. Muhammad
Safdar, Sheeza Khan National Weather Forecasting Center (NWFC), Islamabad. Mr. Nadeem Faisal,
Climate Data Processing Center (CDPC), Karachi. Mr. Ibrar Qureshi, Flood Forecasting Division
(FFD), Lahore. Mr. Nassir Yaseen, National Drought Monitoring Centre (NDMC), Islamabad.
13. REFERENCES
CDPC, Pakistan Meteorological Department. 2019. “Winter Rainfall Update.” 2019.
http://www.pmd.gov.pk/cdpc/winter2019_rainfall_update.htm.
Kalnay, E. 1996. “The NCEP/NCAR 40-Year Reanalysis Project.” Bull. Am. Meteorol. Soc. 77
(3): 437–71. https://doi.org/10.1175/1520-0477(1996)077<0437:TNYRP>2.0.CO;2.
21
ANNEX I
Accumulative rainfall (mm) in January 2020 and their deviation from the normal rainfall.
Punjab
Stations Jan-20 Normal Deviation
BAHAWALNAGAR 42.92 11.4 31.5
BAHAWALPUR,CITY 27.41 7.4 20
BAHAWALPUR,AIRPORT 37.7 ** **
BHAKKAR 41.3 ** **
CHAKWAL 52.81 ** **
D.G.KHAN 18.72 ** **
FAISALABAD 54.81 11.1 43.7
CHAKLALA AIRBASE 98.14 56.2 41.9
ISLAMABAD,ZEROPOINT 111.64 59 52.6
ISLAMABAD, AIRPORT 143.82
**
JHANG 74 ** **
JOHARABAD 28.52 ** **
JHELUM 87.64 40.4 47.2
KASUR 60.62 ** **
KHANPUR 16.02 5 11
KOT ADDU 25.83 ** **
KAMRA AIRBASE 85.01 55.1 29.9
LAHORE, AIRPORT 66.92 22.7 44.2
LAHORE,CITY 64.63 23.2 41.4
LAYYAH 42.53 ** **
MANDIBAHAUDDIN 88.72 ** **
MIANWALI AIRBASE 22.04 23.8 -1.8
MULTAN 28.04 7.6 20.4
MANGLA 105.71 ** **
MURREE 136.21 131.9 4.3
NOORPUR THAL 27 ** **
OKARA 74.6 ** **
RAHIM YAR KHAN 32.01 ** **
GUJRANWALA 98.81 ** **
GUJRAT 94.61 ** **
SAHIWAL 52.02 ** **
SHORKOT AIRBASE 38.02 18 20
SARGODHA AIRBASE 20.43 9.3 **
SARGODHA CITY 23.23 41.4 -18.2
22
SIALKOT CANTT 69.13 ** **
SIALKOT AIRPORT 87.14 ** **
T.T. SINGH 47.21 ** **
HAFIZABAD 93.01 ** **
KHANEWAL 34.03 ** **
NAROWAL 91.42 ** **
ATTOCK 91.8 ** **
Gilgit Baltistan & Azad Kashmir
Stations Jan-20 Normal Deviation
ASTORE 0 43.9 -43.9
BUNJI 21.02 6.4 14.6
BAGROTE 44.54 ** **
CHILAS 14 11.3 2.7
G.DOPATTA 125.4 114.6 10.8
GILGIT 6.93 3.9 3
GUPIS 19 8.8 10.2
KOTLI 105.3 73.9 31.4
MUZAFFARABAD AIRPORT 179 99.3 79.7
MUZAFFARABAD CITY 153 ** **
RAWALAKOT 177.45 ** **
HUNZA 0.8 ** **
SKARDU 60.33 31.4 28.9
Khyber Pakhtunkhwa
Stations Jan-20 Normal Deviation
BALAKOT 105.6 91.4 14.2
BANNU 20 23.3 -3.3
CHERAT 68 47.7 20.3
CHITRAL 66.81 47 19.8
D.I.KHAN 32.73 10.9 21.8
DIR 177.5 112.5 65
LOWER DIR 91 ** **
DROSH 77 49.8 27.2
KAKUL 97.71 69.8 27.9
KALAM 198 ** **
KOHAT AIRBASE 32.01 34.6 -2.6
MALAMJABBA 223 ** **
MIRKHANI 66.8 ** **
PARACHINAR 116 55.9 60.1
PESHAWAR AIRBASE 42.04 40.9 1.1
23
PESHAWAR CITY 47.22 ** **
PATTAN 116.4 ** **
RISALPUR 66.03 45 21
SAIDU SHARIF 89 82.6 6.4
TAKHT BAI 64.4 ** **
Sindh
Stations Jan-20 Normal Deviation
BADIN 0.01 1.2 -1.2
CHHOR 1 0.8 0.2
HYDERABAD 0 1.4 -1.4
JACOBABAD 11.04 3.1 7.9
KARACHI A/P 0.01 8.4 -8.4
LARKANA 13.6 3.3 10.3
MITHI 2 ** **
SH.B.ABAD 7 2.5 4.5
PADIDAN 10.4 2.9 7.5
ROHRI 19.02 4.1 14.9
SUKKUR 14.01 3.5 10.5
M.JO.DARO 11.01 2.6 8.4
THATTA 0 ** **
DADU 10 ** **
MIRPUR KHAS 1 ** **
TANDO JAM 1 ** **
SAKRAND 5.01 ** **
Balochistan
Stations Jan-20 Normal Deviation
BARKHAN 33.02 12.1 20.9
DALBANDIN 72.22 17.3 54.9
GAWADAR 16.6 ** **
JIWANI 55 24.2 30.8
KALAT 129.51 40.9 88.6
KHUZDAR 46.9 18.4 28.5
LASBELA 16 5.6 10.4
NOKKUNDI 48.9 8.7 40.2
PANJGUR 46 13.1 32.9
PASNI 61 24.4 36.6
QUETTA (SH MANDA) 88.61 ** **
QUETTA (SAMUNGLI) 101.07 55.3 45.8
SIBBI 36.01 10.7 25.3
TURBAT 90.4 15.5 74.9
24
ORMARA 72 10.4 61.6
ZHOB 23.01 15.1 7.9
