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Monthly Weather Report
June 2019
Director General
Pakistan Meteorological Department
Prepared by: National Weather Forecasting Center
Islamabad
Contents
SUMMARY ....................................................................................................................................... 1
INTRODUCTION ............................................................................................................................... 2
FIRST DECADE OF THE MONTH ....................................................................................................... 3
SECOND DECADE OF THE MONTH ................................................................................................... 5
THIRD DECADE OF THE MONTH ...................................................................................................... 7
ACCUMULATIVE RAINFALL ........................................................................................................... 9
RAINFALL DEPARTURE ................................................................................................................ 10
TROPICAL CYCLONE TC 02A (VAYU) ....................................................................................... 11
TEMPERATURE ............................................................................................................................. 13
DROUGHT CONDITION .................................................................................................................. 14
WEATHER OUTLOOK FOR JULY ................................................................................................... 15
ACKNOWLEDGMENT .................................................................................................................... 16
REFERENCES ................................................................................................................................. 16
ANNEX I ........................................................................................................................................ 17
List of Figures Figure 1 Synoptic situation 1st to 9th June 2019. 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. ...................................................................................................... 3
Figure 2 Rainfall (mm) distribution on 1st to 10th June 2019. ........................................................ 4
Figure 3 Synoptic situation from 11th to 19th June 2019. 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 4 Rainfall (mm) distribution during 11th to 20th June 2019. ............................................... 6
Figure 5 Synoptic situation from 21st to 29th June 2019. 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 6 Rainfall (mm) distribution during 21st to 30th June 2019. ............................................... 8
Figure 7 Rainfall (mm) distribution during June 2019. ................................................................. 9
Figure 8 Rainfall departure in June 2019 ..................................................................................... 10
Figure 9 Spatial distribution of rainfall (mm) departure in June 2019 ........................................ 10
Figure 10 Track of Tropical Cyclone by Joint Typhoon warning center a) on 12th and b) 17th
June. .............................................................................................................................................. 11
Figure 11 EUMETSAT picture of Tropical Cyclone 02A (VAYU) on 14th June at 0600z. ....... 11
Figure 12 Temperature comparison between normal and June 2019 maximum temperatures. .. 13
Figure 13 Mean temperature anomaly in June w.r.t 1981-2010 .................................................. 13
Figure 14 Drought outlook during the month of June. ................................................................ 14
List of Tables Table 1 Forecast verification contingency table .......................................................................... 12
Table 2 Percentage accuracy of each spell ................................................................................... 12
1
SUMMARY
1. In June 2019 area weighted rainfall of the country remained close to normal at -1 %.
2. On regional basis rainfall was above normal in Gilgit Baltistan 292%, Balochistan +3%,
and below normal in Sindh -79%, Punjab -14%, Khyber Pakhtunkhwa -12%, and Azad
Jammu and Kashmir -2%.
3. Highest accumulated precipitation during the whole month was recorded in Astore, Gilgit
Baltistan, 112 mm.
4. Highest amount of rainfall during 24 hours was recoded in Astore, Gilgit Baltistan 65.2
mm.
5. Highest maximum temperature of 51.0℃ was recorded in Jacobabad on 1st and 2nd June.
2
INTRODUCTION
June is one of the hottest months in the country. During this month mean minimum temperature
varies from 11.0℃ in Astore to 30.7℃ in Sibbi. While mean maximum temperature ranges from
24.2℃ in Astore to 45.4℃ in Sibbi, Balochistan. Normal area weighted rainfall in June for
Pakistan is 18.6 mm. For Khyber Pakhtunkhwa 39.6 mm, Punjab 29.4 mm, Balochistan 9.0 mm,
Sindh 10.2 mm, Azad Jammu and Kashmir it is 25.9 mm and Gilgit Baltistan 13.6 mm. In June
2019 area weighted rainfall of Pakistan remained close to normal -1%. 1. On regional basis
rainfall was above normal in Gilgit Baltistan 292%, Balochistan +3%, and below normal in Sindh
-79%, Punjab -14%, Khyber Pakhtunkhwa -12%, and Azad Jammu and Kashmir -2%. In this
month highest maximum temperature of 51.0℃ was recorded in Jacobabad on 1st and 2nd June.
Highest accumulated precipitation during the whole month was recorded in Astore, Gilgit
Baltistan, 112 mm. While amount of rainfall during 24 hours was recoded in Astore, Gilgit
Baltistan 65.2 mm. For a better understanding of the weather situation during the month, it is
divided into three decades.
3
FIRST DECADE OF THE MONTH
Synoptic situation during 01st to 9th June obtained by NCEP/NCAR reanalysis dataset (Kalnay
1996) is shown in figure 1. During 3rd to 6th June a closed circulation was present at 850 hPa.
While a shallow westerly wave also persisted during 3rd to 7th June.
Figure 1 Synoptic situation 1st to 9th June 2019. 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.
4
Rainfall distribution during the first decade is shown in figure 2. During this time period rainfall
occurred in upper areas of the country and in isolated parts of southeastern Sindh. Most of the
southern parts of the country remained dry.
Figure 2 Rainfall (mm) distribution on 1st to 10th June 2019.
5
SECOND DECADE OF THE MONTH
Synoptic situation during the second decade of the month is shown in figure 3. Most parts of the
country remained predominantly in the grip of a westerly wave. While a cyclonic storm can be
seen brewing in the Arabian Sea. This cyclonic storm(02A) was named as “VAYU”. It latter
tracked northwards and fizzled out near the Indian Gujrat coast.
Figure 3 Synoptic situation from 11th to 19th June 2019. 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 of rainfall from 11th to 20th June 2019 is shown in figure 4. It shows that most
of central and northern parts of the country along with southeastern parts of of the country received
rainfall.
Figure 4 Rainfall (mm) distribution during 11th to 20th June 2019.
7
THIRD DECADE OF THE MONTH
The synoptic situation during the last decade is shown in figure 5. A westerly wave gripped most
parts of the country during the last decade. While a closed circulation was also present at lower
level from 27th to 30th June.
Figure 5 Synoptic situation from 21st to 29th June 2019. 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
Figure 6 represents the spatial distribution of rainfall during the time period. In this most parts of
the country except for western parts of Balochistan and some parts of upper Sindh remained dry.
A center of maximum rainfall is present over Islamabad.
Figure 6 Rainfall (mm) distribution during 21st to 30th June 2019.
9
ACCUMULATIVE RAINFALL
In June most parts of the country except for southwestern parts of Balochistan received rainfall.
Figure 7 represents the spatial distribution of rainfall during the month of June. The center of
maximum rainfall is around Islamabad. Details of rainfall are appended in annexure I.
Figure 7 Rainfall (mm) distribution during June 2019.
10
RAINFALL DEPARTURE
During this month area weighted rainfall of the country remained close to normal -1%. On regional
basis rainfall was above normal in Gilgit Baltistan 292%, Balochistan +3%, and below normal in
Sindh -79%, Punjab -14%, Khyber Pakhtunkhwa -12%, and Azad Jammu and Kashmir -2%.
(CDPC 2019) represented in figure 8. Figure 9 shows the spatial distribution of rainfall departure
in the month of June with respect to the base period of 1961-2010. It shows above normal rainfall
in parts of Gilgit Baltistan while rainfall remained deficient in most northeastern parts of Punjab
and Kashmir.
Figure 8 Rainfall departure in June 2019
Figure 9 Spatial distribution of rainfall (mm) departure in June 2019
11
TROPICAL CYCLONE TC 02A (VAYU)
A tropical cyclone 02A named as VAYU, (a Sanskrit word meaning wind) was formed over
Arabian Sea in June. Its genesis started, on 9th June at 2300 UTC as a cyclonic circulation near
10.5°N, 72.2°E off the Indian coast of Cochin, India. It intensified into a cyclonic storm on 10th of
June 2019. In the initial stages it was forecasted to track north-northeast wards towards the Indian
Gujrat coast and was expected to landfall there. However, in the latter stages it started drifting
northwestwards and then took a sharp turn towards north-northeast wards on 14th June. The system
latter weakened significantly and dissipated on sea near the Indian Gujrat cost by 17th June. Track
as depicted by Joint Typhoon Warning Center, USA on 12th and 17th June are shown in figure 10.
While figure 11 shows EUMETSAT picture of Tropical Cyclone 02A (VAYU) on 14th June at
0600z
Figure 10 Track of Tropical Cyclone by Joint Typhoon warning center a) on 12th and b) 17th June.
Figure 11 EUMETSAT picture of Tropical Cyclone 02A (VAYU) on 14th June at 0600z.
a) b)
12
FORECAST VALIDATION
An attempt is made to substantiate the accuracy of precipitation forecasts issued in June. 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 1 Forecast verification contingency table
Observed
Yes No Total
Foreca
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 2 Percentage accuracy of each spell
Rainfall spells Percentage accuracy
First Decade 92
Second Decade 79
Third Decade 79
Average 83
13
TEMPERATURE
During the month of June slightly below normal maximum temperatures were recorded in
Pakistan. Maximum temperatures in Gilgit Baltistan and Azad Jammu Kashmir remined below
normal. Sindh recorded slightly above normal maximum temperatures while in Balochistan,
Punjab and Khyber Pakhtunkhwa maximum temperatures remained close to normal. Figure 12
represents the comparison of June 2019 and mean maximum temperatures over the country. Spatial
distribution of anomaly of mean temperature is shown in figure 13. It Indicates that northern most
parts of the country remained cooler than normal in the month of June While parts of Sindh and
northeastern Punjab were warmer than normal.
Figure 12 Temperature comparison between normal and June 2019 maximum temperatures.
Figure 13 Mean temperature anomaly in June w.r.t 1981-2010
14
DROUGHT CONDITION
According to the latest drought analysis done by National Drought Monitoring Center of PMD,
Wet conditions prevailed over most of the northern most parts of the country. During the month
of June, rains in the agricultural plains of Khyber Pakhtunkhwa and Punjab gave relief to the crops.
Some districts in Sindh are under Moderate drought conditions due to no or very less precipitation
and persistent dry conditions over there. Drought analysis results using different indices is
represented in figure 14.
Figure 14 Drought outlook during the month of June.
15
WEATHER OUTLOOK FOR JULY
Global Climate indicators such as El-Nino Southern Oscillation and Indian Ocean Dipole (IOD)
are expected to remain in positive phase during the month. On the basis of prevailing global
atmospheric and ocean conditions, Following are the main features of weather outlook for the July
2019;
• Below normal rainfall is expected in the country during the month.
• Two to three spells of rainfall, embedded with isolated extreme precipitation events, are
expected in the northern half of the country during the period.
• Mean temperature is likely to remain 1-2°C above normal during the month.
• Due to above normal temperature, snow and glacier melt contribution in the flow of
Indus River will be enhanced during the month.
16
ACKNOWLEDGMENT
This work is the combined effort of all the forecasting team. Special thanks to Mr. Farooq Dar,
Ms. Ruqiya Mehmood and Mr. Muhammad Safdar, 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
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.
17
ANNEX I
Accumulative rainfall (mm) in June 2019, and their deviation from the normal rainfall.
Punjab
Stations Jun-19 Normal Deviation
Murree 83.74 142 -58.3
Lahore, Airport 71.63 54.5 17.1
Noorpur Thal 69.21 ** **
Kot Addu 66.02 ** **
Faisalabad 55.01 43.8 11.2
Multan 53.62 13.1 **
Joharabad 43.51 ** **
Narowal 42.61 ** **
Mangla 40.34 ** **
Kasur 40.03 ** **
Islamabad, Zeropoint 31.03 78.2 -47.2
Layyah 30.21 ** **
T.T. Singh 29.1 ** **
Lahore, City 28.54 55.1 -26.6
Attock 27.04 54.7 **
Bahawalpur, City 26.81 16.2 10.6
Bhakkar 26.5 ** **
D.G.Khan 26.01 ** **
Jhelum 24.54 57 -32.5
Islamabad, New Airport 23.21 **
Jhang 22.82 ** **
Bahawalpur, Airport 19.5 ** **
Khanewal 19.02 ** **
Gujrat 18.7 ** **
Sargodha A/P 17.03 **
Mandibahauddin 16.56 ** **
Khanpur 15.41 6.5 8.9
Okara 15.41 ** **
Sargodha City 15.06 26.8 **
Islamabad, Old Airport 13.83 75.3 **
Shorkot 11.04 40 **
Sialkot Cantt 10.03 64.1 -54.1
Gujranwala 7.62 ** **
18
Bahawalnagar 6.01 39.2 -33.2
Sahiwal 6.01 ** **
Sialkot Airport 4.45 ** **
Chakwal 2.25 ** **
Mianwali 1.05 41.5 **
Hafizabad 0.03 ** **
Rahim Yar Khan 0.01 ** **
Gilgit Baltistan & Azad Kashmir
Stations Jun-19 Normal Deviation
Astore 112.03 28.8 83.2
Muzaffarabad 106.21 115.9 -9.7
Garidopatta 83.6 112.3 -28.7
Bagrote 67.41 ** **
Skardu 54.48 10.1 44.4
Rawalakot 54.22 ** **
Kotli 49.06 80.9 -31.8
Chilas 34.62 13.9 20.7
Gilgit 33.38 11.8 21.6
Bunji 32.46 13.3 19.2
Gupis 20.7 21.7 **
Hunza 7.5 ** **
Khyber Pakhtunkhwa
Stations Jun-19 Normal Deviation
Abbottabad 93.82 88.9 4.9
Dir 91 56.4 34.6
Malamjaba 77 ** **
Kohat 70.04 31.7 **
Kalam 55.8 ** **
Balakot 54.31 92.9 -38.6
Pattan 37 ** **
D.I.Khan 33.02 21.7 11.3
Mirkhani 26 ** **
Parachinar 17 52.5 -35.5
Saidu Sharif 15.5 57.5 -42.0
Cherat 15 25.6 -10.6
Peshawar City 14.04 ** **
19
Drosh 13.4 24.5 -11.1
Peshawar A/P 10.04 20.4 **
Risalpur 9.06 21.3 **
Chitral 8.74 12.2 -3.5
Bannu 7 28.8 -21.8
Lower Dir 1 ** **
Sindh
Stations Jun-19 Normal Deviation
Mithi 14 ** **
Badin 9.02 9.6 -0.6
Sukkur 2 4.5 **
Karachi A/P 1.6 10.8 -9.2
Chhor 0 16.3 -16.3
Hyderabad 0 4.4 -4.4
Jacobabad 0 3.2 -3.2
Larkana 0 8.5 -8.5
Shaheed Benazirabad 0 5 -5.0
Padidan 0 4.2 -4.2
Rohri 0 6.4 -6.4
Mohenjo-Daro 0 2.5 -2.5
Thatta 0 ** **
Dadu 0 ** **
Mirpur Khas 0 ** **
Tando Jam 0 ** **
Balochistan
Stations Jun-19 Normal Deviation
Barkhan 69.01 47 22.0
Zhob 34 19.8 14.2
Sibbi 18 13 5.0
Lasbela 10.01 10 0.0
Khuzdar 9 13.5 -4.5
Kalat 1 8.9 -7.9
Dalbandin 0 4 -4.0
Gwadar 0 ** **
Jiwani 0 9.9 -9.9
Nokkundi 0 2.6 -2.6
20
Panjgur 0 6.4 -6.4
Pasni 0 8.5 -8.5
Quetta 0 ** **
Quetta Airport 0 2.8 **
Turbat 0 18.5 -18.5
Ormara 0 22.5 -22.5
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