Government of India India Meteorological Department (Ministry of Earth Sciences) Subject: Current weather conditions and forecast for next two weeks

Transcription

1 Government of India India Meteorological Department (Ministry of Earth Sciences) Press Release Dated 18 June, 2010 Subject: Current weather conditions and forecast for next two weeks Advance of monsoon During the week, Southwest monsoon advanced into remaining parts of Karnataka, Andhra Pradesh, Maharashtra, Orissa and West Bengal, some parts of south Gujarat & south Madhya Pradesh, most parts of Chhattisgarh & Jharkhand and some parts of Bihar. The Northern Limit of Monsoon (NLM) as on 18th June, 2010 passes through Lat.22.0 N/Long.60.0 E, Lat.22.0 N/Long.69.0 E, Rajkot, Ahmedabad, Indore, Seoni, Pendra, Ambikapur, Daltonganj, Gaya, Muzaffarpur and Raxaul. The map showing NLM is shown in the figure -1. Fig.1. Advance of southwest monsoon 2010

2 Rainfall during the week (10-16 June) During this week, monsoon was active/ vigorous over many parts of south peninsula, where the rainfall was above normal by 92%. However, rainfall over northeast India remained subdued during the week. Isolated heavy to very heavy rainfall was also experienced along the west coast during the week. The statistics of the weekly rainfall are given below: Regions Actual Rainfall (mm) Normal Rainfall (mm) % Departure from LPA Country as a whole Northwest India Central India South Peninsula North East India

3 Out of 36 meteorological sub-divisions, rainfall was excess in 12, normal in 04, deficient in 11 and scanty in 09 sub-divisions during the week. The monsoon rainfall activity and its distribution during the week are given below.

4 Seasonal Rainfall Scenario (1-17 June) The cumulative seasonal rainfall for the country as a whole during this year s monsoon has so far upto 17 June been 3% below the Long Period Average (LPA). Out of 36 meteorological subdivisions, the rainfall has been excess over 11, normal over 12 and deficient /scanty over 13 subdivisions. Details of seasonal rainfall over the four broad homogeneous regions of India are given below: Actual Rainfall (mm) `Regions % Departure from LPA 1-10 June 1-17 June 1-10 June 1-17 June Country as a whole Northwest India Central India South Peninsula North East India Current synoptic conditions 1) Strong pressure gradient is prevailing along the west coast. 2) An off-shore trough extends from south Gujarat coast to Kerala coast. 3) A shallow shear zone extends from east-central Arabian Sea to North Bay of Bengal. 4) A cyclonic circulation lies over Bihar and adjoining areas in lower tropospheric levels. Large scale features 1) The MJO signal continues to remain weak. 2) The forecast from statistical models are not indicating better OLR patterns during next one week.

5 Prognosis based on Numerical Weather Prediction (NWP) Models 1) Interpretation of numerical model outputs indicates that fairly widespread rainfall activity is likely the west coast and northeast India. 2) Subdued rainfall activity would occur over the rest of the country. 3) No formation of any low pressure area in Bay of Bengal during next one week. Forecast for next one week (18-24 June) 1. A temporary weakening of the monsoon current is likely during the week with subdued rainfall activity over most parts of country except along the west coast ( Konkan & Goa, Coastal Karnataka) and over northeastern States. 2. No major advance of southwest monsoon would occur over eastern and central India during next one week. 3. Fairly widespread rainfall activity would occur over northeastern States and along the west coast with isolated heavy to very heavy falls during first half of the week. 4. Fairly widespread rainfall activity would occur over West Bengal & Sikkim and scattered over Bihar, Jharkhand and Orissa. 5. Subdued rainfall activity would occur over interior peninsula and adjoining parts of the central India during the week. 6. Weather over Northwest plains would remain mainly dry except isolated thunderstorm activity. Outlook for next one week (25 June- 01 July) Strengthening of monsoon flow and its sustenance is expected from 25th onwards with likely formation of a Low pressure over North Bay of Bengal. This may lead to increase in the rainfall activity over East and Central India. Also the east-west seasonal trough may establish which is likely to increase the thunderstorm activity over Gangetic plains.