Wednesday, June 30, 2010

This write up is updated on 2nd. July @ Due to server difficulty, the blog is unable to post new updates directly in current dates. Hence it appears in the last blog dated 30th. June. I will update in this date, with a note till the difficulty is rectified.

The Upper Air Circulation which formed over the bay, has now, as an UAC, started moving inland. As seen in the clouding imagery, the system now seems to  be over the Chattisgarh/Vidharbh region. I am unable to locate this system as a low at MSLP.

TheThai MSLP map (as of Friday evening), nor the latest IMD map show anything in terms of the system coming to sea level as a low.

This (UAC) may move westwards across Central India, i.e. North Maharashtra and thence to Gujarat. Observing the moisture attracting capacity of this, we can expect very  good rainfall activity  from Friday thru Sunday over areas from Vidharbh to North Maharashtra, Gujarat and rest of central India.In fact regions of the Maharashtra section have recieved rains ranging from 30-80 mms.

On its path, i foresee an incursion of moisture from the Arabian Sea into Gujarat and onto the west coast north of Mumbai.South Coastal Gujarat regions, areas from Surat to Porbunder and the gulf of Cambay, could recieve rainfall upto 200-250 mms Saturday thru Sunday.
Good, heavy rains upto 100-125 mms, could be expected elsewhere in east Gujarat and Saurashtra, and in North madhya Maharastra and Marathwada regions.
A deficit Saurashtra could get good relief from this rainfall.

Mumbai, should get heavy rains on Saturday, as the UAC moves westwards. On Saturday, the city can expect rainfall at regular intervals, with some very heavy falls, throughout the day, with rainfall amounting to around 70-80 mms.Observing the movement of the circulation, I feel Mumbai rainfall will decrease from Sunday evening, about 25-35 mms on Sunday, as the system moves west, and weakens.

Just to mention, there have been 2/3 previous occasions in the last 9 years, when an upper air circulation at 850 hpa has been reported to stay put in Gujarat region for upto 5 days. Due to a sudden burst of moisture from the Arabian Sea, it maintained its strenght, and even continued to pour heavy rains in Gujarat and coastal regions.

However, advancement of monsoon beyond East Uttar Pradesh, even with the help of a predicted cyclonic circulation is doubtful.This system is short lived, and is expected to whizz past the central and western areas fast, within 3 days.

Highest, all India Rainfall from 1st.June-30th. June with deviations:

Cherrapunji: 3340 mm (+546)
Harnai: 1117 mm (+430)
Khozikode: 1016 mm
Passighat : 1014 mm (+165)
Lakhimpur: 1010 mm(+351)
Agumbe: 1093 mm
Goa: 981 mm (+112)
Mumbai Colaba: 947 mm (+396)
Mumbai S'Cruz: 712 mm (+168)
Mahableshwar: 577 (-289)*
* given bcoz it is supposed to be among the highs normally.

June 2010 is over and done with. The story of the Monsoon till end June is vague and haphazard. A stunted progress, and a completely distorted movement.
The monsoon set in over Kerala on May 31 and reached Mumbai on 11 June. A day early, and a date late to the normal dates.

It  covered the northeastern states slightly earlier than the normal time, but reached Kolkata only on June 13, about a week later than normal.

As of Tuesday, the monsoon has reached up to central and east India, as per the Monsoon limit line in the IMD map.
Rainfall activity  being reported from most of the areas covered are not too uniform, and are sporadic and scanty in the Gujarat region. (Shall put up the monsoon performance map/report till end June as soon as it is published by IMD).
Maharashtra is still on the "pre-monsoon " stage, with thundershowers developing, specially over North Mah. region, every afternoon,but pouring heavy rains in very isolated pockets, and clearing by the the morning.

Else, the rain accumalation map shows some precipitation along west coast, and in patches elsewhere.

But things do not differ much than what has been mentioned in my blog dated 22nd. June, from which I reproduce - "If, after this week, the axis of the monsoon shifts further north towards the Himalayas, and deepens,then the entire peninsula region is in for an unwanted "break". This may delay the monsoon progress into the Northern regions and subsequently into the North-West corner". Mentioned also in my footnote of the blog of 20th.
"The "interfering" monsoon axis has always been my main concern of worry, and has proved that it can create a sort of break monsoon.
My worst fears were that the monsoon would halt, and it sure did !  From the18th, its been stationary,  there has not been any advance of the monsoon over new areas since then.
There were many forecasts and "hopes" of the monsoon advancing, but as mentioned in "Vagaries", the MJO has been consistently negative for further advance since the last 12 days.Readers must have checked this point on the link provided in my blog dated the 22nd.

The 200 level jet streams are still stuck at 20N, and will allow the monsoon to progress only when it shifts Northwards.

Now, any further progress will be halted till the formation of a monsoon low pressure area/depressions over the Bay of Bengal.
Interestingly, the COLA has estimated an UAC to form over NorthMaharashtra/South 2nd, and the circulation is projected to move west. If so, then good and much needed rains could commence in Saurashtra on the weekend, as COLA estimates rainfall upto 100 mms in the region.
I will cautiously monitor the forming of the UAC.

Strong westerly flows, due to the axix position, over most parts of northwest/ central India and frequent western disturbances have disturbed the monsoon's smooth advance. And the W.D's are making "hay" due to the total absence of any systems from the bay. These are the days for the bay to dominate, not the W.D's.
Now, IMD has said in a special bulletin on Tuesday "that monsoon is unlikely to advance into the remaining parts of east and central India during the next four days.the remaining parts of central and east India are expected to be covered by the end of first week of July and the entire country by the middle of July".
Like i mentioned, nothing on the horizon till 5th. July at least. We preview and monitor again for any good developments each day.

Mumbai June report tomorrow.



Hello! I also write about weather..
check this blog
Mr.Ashok Patel had given your reference.

Anonymous said...

I checked the blog 'METD', although it's Nagpur specific and hence not easy to relate for someone who is in Mumbai, one must say that he does attempt to provide 'Now time' weather with all the updates. Also, I liked his one constant line "remove all electrical appliances" :-)

Keep the blog going

Anonymous said...

What is the forecast for Mumbai, haven't seen your forecast in the last couple of days

Outlook for 27th/28th/29th:(This week till Thursday/Friday) Mumbai: Partly cloudy with occasional rain showers. Warm in the day with period...