The feared "El Nino" - South West Monsoon killer is almost here !!
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Further warming of the central Pacific ocean has created a right scenario for El Nino in next 1 or 2 months. This parameter is really not good for our important South West Monsoon.
Here's the latest, 29-Apr-2015, report from BOM-Australia (www.bom.gov.au) ...
" ENSO indicators in the tropical Pacific are approaching El Niño levels. Sea surface temperatures now exceed El Niño thresholds and trade winds have remained weaker than average for several weeks. This suggests some coupling between the ocean and atmosphere may be occurring. If these patterns persist or strengthen, El Niño will become established. Based upon model outlooks and current observations, the Bureau's ENSO Tracker is at ALERT status. This indicates that there is triple the normal chance of El Niño in 2015."
The Indian Ocean Dipole (IOD) ...
" Climate models surveyed in the model outlooks favour a continuation of a neutral phase of the IOD over at least the next few months. Positive IOD events are more likely to occur in conjunction with El Niño, therefore climatologists will closely monitor the Indian Ocean for any early signs of a developing event. "
In fact, a positive IOD along with El Nino will actually counteract with the negative effect of the El Nino on SW Monsoon... click here for more on this
Central, N-W India Heat LOW
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As of today, 3-May-2015, the LOW pressure generated by HEAT over N-W, Central, East India is around 1006mb and this is HIGH at this time of year. It should be around 1000 / 1002mb.
Heating has just started over N-W, central, East India after a long wet April due to strong W.Ds.
This heating is further expected to be disturbed by more W.Ds from 6-May to 12-May. .
Sea Surface Temperature(SST) over Bay and Arabian sea
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SST over most of Bay is around or above 30 C, meanwhile there's almost NO reduction in SST seen along Somali seas, this is sign that less winds are reaching Somali coast from Mascarene HIGH pressure. Note, around 25-May, the SST along Somali coast should be around 20 C.
Bay LOW
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The expected Bay LOW during 2nd or 3rd week of April did not materialize and till now there's less signs of it. Today, a weak low-level circulation seen over S-W Bay and Srilanka, this is expected to persist and drift West into Gulf Mannar and S Tamilnadu during next 2 or 3 days. A Bay LOW is an important parameter before the onset of Monsoon winds into S,S-E Bay and S Andaman Islands.
Latest GFS run, suggests that Monsoon winds / Cross equatorial winds will reach S,S-E Bay by 16/17-May !
Mascarene HIGH pressure system and Cross Equatorial Winds
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A good high pressure system with pressure up to 1028mb is seen over South Indian Ocean, slightly East to the expected position, and this is OK at this point of time.
As of now very less winds are reaching the Horn of Africa, this is expected to pickup around or after 10-May-2015.
Long Range Forecast by JAMSTEC
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For your info, a Long range model of 24-Apr-2015 predicts a above normal rainfall for Kerala, Karnataka coast, Andaman Islands and East, E-central and N-E zones of India from June to August 2015.
------------------------------------------------------------------------------------------
Further warming of the central Pacific ocean has created a right scenario for El Nino in next 1 or 2 months. This parameter is really not good for our important South West Monsoon.
Here's the latest, 29-Apr-2015, report from BOM-Australia (www.bom.gov.au) ...
" ENSO indicators in the tropical Pacific are approaching El Niño levels. Sea surface temperatures now exceed El Niño thresholds and trade winds have remained weaker than average for several weeks. This suggests some coupling between the ocean and atmosphere may be occurring. If these patterns persist or strengthen, El Niño will become established. Based upon model outlooks and current observations, the Bureau's ENSO Tracker is at ALERT status. This indicates that there is triple the normal chance of El Niño in 2015."
" Climate models surveyed in the model outlooks favour a continuation of a neutral phase of the IOD over at least the next few months. Positive IOD events are more likely to occur in conjunction with El Niño, therefore climatologists will closely monitor the Indian Ocean for any early signs of a developing event. "
In fact, a positive IOD along with El Nino will actually counteract with the negative effect of the El Nino on SW Monsoon... click here for more on this
Central, N-W India Heat LOW
---------------------------------------------------
As of today, 3-May-2015, the LOW pressure generated by HEAT over N-W, Central, East India is around 1006mb and this is HIGH at this time of year. It should be around 1000 / 1002mb.
Heating has just started over N-W, central, East India after a long wet April due to strong W.Ds.
This heating is further expected to be disturbed by more W.Ds from 6-May to 12-May. .
Sea Surface Temperature(SST) over Bay and Arabian sea
------------------------------------------------------------------------------------
SST over most of Bay is around or above 30 C, meanwhile there's almost NO reduction in SST seen along Somali seas, this is sign that less winds are reaching Somali coast from Mascarene HIGH pressure. Note, around 25-May, the SST along Somali coast should be around 20 C.
Bay LOW
---------------------
The expected Bay LOW during 2nd or 3rd week of April did not materialize and till now there's less signs of it. Today, a weak low-level circulation seen over S-W Bay and Srilanka, this is expected to persist and drift West into Gulf Mannar and S Tamilnadu during next 2 or 3 days. A Bay LOW is an important parameter before the onset of Monsoon winds into S,S-E Bay and S Andaman Islands.
Latest GFS run, suggests that Monsoon winds / Cross equatorial winds will reach S,S-E Bay by 16/17-May !
Mascarene HIGH pressure system and Cross Equatorial Winds
------------------------------------------------------------------------------------------
A good high pressure system with pressure up to 1028mb is seen over South Indian Ocean, slightly East to the expected position, and this is OK at this point of time.
As of now very less winds are reaching the Horn of Africa, this is expected to pickup around or after 10-May-2015.
Long Range Forecast by JAMSTEC
-------------------------------------------------------
For your info, a Long range model of 24-Apr-2015 predicts a above normal rainfall for Kerala, Karnataka coast, Andaman Islands and East, E-central and N-E zones of India from June to August 2015.
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