Tuesday, October 31, 2006

The deep depression mentioned,progressed to the status of a cyclone(Ogni),and crossed the Andhra coast on Monday.But it has not progressed or moved much inland,due to the domineering upper westerly trough which did not allow it to move inland.In fact the sytem has already weakened.But the rain belt has moved away northwards.
Except for the IMD,no major international weather models has acknowledged the cyclone or registered it.This is because it has developed too near the coast,in fact "half over water and half over land".Only the cyclones with the required speed and intensity over international waters are likely to get the attention.

But the sytem has rained heavily over coastal Andhra,with Machlipatanam getting 34cms.in a day.

Scattered rain was also recorded in intereior Andhra and interior Maharashtra today.

Sunday, October 29, 2006

After pouring heavy rain over the Tamil Nadu coast,these rains will possibly move a little north.A deep depression that has formed off the Andhra Coast is likely to cross the coast of Andhra by Monday,and as a result bring heavy rain to Andhra,and later to interior Maharashtra.Areas of South Madhya Maharahtra and Marathwada will get some showers from Tuesday,and Mumbai also may see some rain in the next 48 hrs.

This will result in more sultry weather for Mumbai in the next 48 hrs.As a result,the night temperatures which had just started to drop in the Pune,Nasik,Aurangabad and M.P.region,will rise again,at least for a few days.

Another system seems to be forming in the S.Arabian Sea.It has to be observed,and the movement and development speed to be observed.

Both the above systems are formed as the ITCZ moves southwards seasonally.

Temperature wise,no sharp falls or abnormal temperatures recorded in the sub continent except for the severe heat in Mumbai,mentioned last week.The first below zero temperature of the season in the mid hills or plains(outside the higher reaches of Kashmir and H.P.),was -1.7°c at Kalpa(H.P.)recorded on 24th.October.

Sunday, October 22, 2006

For those who had decided to go to the hills for the Divali vacations,it was certainly a good choice.Divali day,Sunday 22nd.October was certainly a very hot day in Mumbai.It was second only to Hyderabad(Pakistan),in the entire sub continent region.Hyderabad(Pakistan)was 37°c,and Mumbai(Santacruz),Ahmedabad and Baroda were 36°c on Sunday.

The delay in the setting in of the westerly sea breeze is the cause of the heat in Mumbai.The winds were expected to change with the westward movement of the ongoing W.D.Otherwise,with the W.D.now moving away,temperatures have fallen by about 2-3°c in the North of Pakistan and India,thus being normal to 1°c below normal.

Thursday, October 19, 2006

ORIONID METEOR SHOWER: This weekend, a mild but pretty flurry of meteors will shoot out of the constellation Orion. The source is Halley's Comet. Although the comet itself is far away, ancient clouds of dust from the comet are nearby, and Earth is about to run through them. The best time to look is Saturday morning, Oct. 21st. Dozens of meteors might streak across the sky during the hours before sunrise. Dark skies are recommended!

If interested in more details,check at spaceweather.

Wednesday, October 18, 2006

With the monsoon gone, the winds have immedietly changed direction and are now, blowing from the north east, almost throughout the central parts of India.
The city of Mumbai has suddenly started heating up, taking the locals by surprise. This is due to the total absence of the westerly sea breeze which has kept the city cool for the last 5 months. Easterlies are now blowing over the city and thus keeping the temperatures high. This is expected to reverse in another 2 days,and temperatures are expected to fall in North India,Gujarat and North Maharashtra.In the picture above,notice the sudden rise in the temperature from 11th October,the day the rains stopped in Mumbai.
The South West Monsoon has been formally been announced as widhrawn from the sub continent as on 17th October. Overall, it was -1% for the country as a whole and excess in the central parts. Parts of the extreme south and North East were in the deficit.
I agree with Jim's blog of yesterday, that there are many factors that have a bearing on the final performance of the South West Monsoon. Starting with the temperatures of March in India to the sea temperatures off the coast of Sudan, a variety of parameters have been proved to have an effect on the rains. The building up of the heat low, and its timing have an important bearing on the time of arrival of the monsoon. Another far away factor, in fact the initial, is the cooling of the Southern Indian Ocean between Africa and Australia, to create the"high" there and shoot off the trade winds towards the equator. I think maybe we should leave this discussion for the next season.

Saturday, October 14, 2006

The W.D. I mentioned yesterday is quite active in the higher reaches and the Northern areas. The Dhauladhar ranges in Kangra district, Rohtang Pass, Saptrishi ranges and other peaks in tribal Lahaul and Spiti district and Saach Pass in Chamba district of Himachal Pradesh had a spell of intermittent snowfall, creating cold wave conditions in the region.Dharamsala and its adjoining areas received intermittent rains accompanied by strong winds while Dhauladhar ranges overlooking the Kangra valley, had snowfall since yesterday, the met department said.
The Rohtang Pass (13,050 ft) had moderate snowfall for second day on Saturday and 10 cm of fresh snow had accumulated on the pass till this evening.Shimla and its surrounding areas were lashed by icy winds, making people shiver during the evening hours.(Report from T.O.I.).

Reports from Pakistan also speak of a heavy and violent dust storm in Lahore,with 100kmph. winds.

Friday, October 13, 2006

Having pushed the South West monsoon down,the first W.D. of the winter has immiedietly arrived over the northern areas of Pakistan and India.The system is moderate and has poured fairly good amounts of rain over Pakistan today.Rawalpindi 43mm and other stations between 20-40mm.Srinagar had a cloudy day and the day temperature dropped from yesterdays 27° to 17° (-5°c below normal) today.Early arrival of a moderate W.D. will bring in the cooler climes to the Northern parts of the sub continent and drier air will push down over central India.

Meanwhile the rain figures for the monsoon season for some Maharashtra cities (with last years rain in brackets) are:

Mumbai Colaba: 2377mm (2316mm),Santacruz:3030mm (3321mm),Pune:1151mm (1260mm),Mahableshwar:8478mm (8628mm).

Thursday, October 12, 2006

Now, with the anticyclone well placed over the North and the west, it seems the monsoon has finally moved out and widhrawn from the peninsular, at least from above the 15°N. I say it seems as the IMD has not officially widhrawn the monsoon from below the 20°N. till 12th October. From my personal jottings, I read that one of the later dates of monsoon widhrawal for Mumbai, in the recent past was 17th October in 1983.

For the month of October, Mumbai (Colaba) has had 246mm of rain and Santacruz 200mm as on date. However, for the rcords, the wettest October for Colaba was in 1917, when the month had 507 mm.

With the monsoon now over from the major portion of North and central India, the temperatures are rising due to the absence of W.D. and cooler winds from the North West. Temperatures in most parts of India, except the South, are 3-5°c above normal. See map.

Also, most of the sub continent is quite (after4 months), and will remain so for a week at least, before the winter rains start in the south. There may be some precipitation in the extreme north due to the W.D. now over the middle east.

Tuesday, October 10, 2006

The off shore trough along the west coast persists,and continues to produce some pockets of heavy rain along the coast ,measuring 4-6cms,along the west coast,upto Mumbai.Mumbai had a a drizzle today morning with thunder and lightning.This trough will remain for another 24 hrs. before the anticyclone pushes down and drives the South West Monsoon away.The South West Monsoon has widhdrawn upto 20°N as on 9th.October.The North East Monsoon will then set in,as indicated by a few models.It is likely to set in by 14th./15th.
Just like a busy Pacific season had a favourable impact on the South West Monsoon,the development of the El Nino effect is to be watched on the Winter Monsoon in South India.

Saturday, October 07, 2006

The persistant remnant of 05B in the Arabian Sea has finally dissoved and is now converted to a trough of low presurre off the west coast.The trough should be active for another day or two and precipitate more rain in interior Maharashtra and may keep the widhrawal on hold for a couple of days. No major weather development may take place in the regions of Maharashtra,Gujarat and the central peninsular from the 9th.,resulting in the widhrawal of the monsoon.The developing low in the bay,will then move towards the South India coast and commence the North East Monsoon.

As mentioned,the temperatures in the areas devoid of the monsoon are high for this time with Turbat in Pakistan going to 44°c today,and Ganganagar in Rajasthan at 41°c.However the minimums are 1-2°c above the normal.

An interesting development is the returning trend of the El Nino.
NASA satellites indicate El Nino has returned to the tropical Pacific Ocean, although in a relatively weak condition that may not persist.
During the past several weeks, satellites have observed a general warming of ocean temperatures. However it still weak and the progress has to be monitored.

Friday, October 06, 2006

With the monsoon still hovering over peninsular India, the advent of winter conditions seem to be somewhat halted, at least in Northern most parts of India and North West India. The day temperatures are above normal over the northern parts as is apparent from this map. The maximum temperatures elsewhere in Middle east are also still high with Makkah at 43°c, Sharjah and Nawabshah at 42°c and Muscat Airport and Dubai at 41°c. With the advent of a W.D. (not yet in formation), the winter temperatures may start falling. Daytime highs in Pakistan and India are 41° to 40° at their highest now.

Elsewhere in U.K. the scene is similar, with above normal temperatures. An interesting write up in the BBC on 3rd, produced below, says it all.
"Two countries on opposite sides of the world have experienced the warmest September for almost a century. Both the UK and parts of Australia have been basking in unseasonably warm weather, with temperatures several degrees above the average. Some western parts of Victoria, Australia, have recorded the warmest September since 1907. In Horsham the average maximum temperature for September worked out to be 20.4C (69F), almost 3C above what it should be in September. This is also just 0.5C below the all time record for the warmest September, which was 20.9C in 1907. Temperature records have also been smashed here in the UK. September 2006 has proved to be the warmest September since records began. Both day-time and night-time temperatures averaged out at 15.4C (60F), which is 3.1C above the long term average. This smashed the previous record of 14.7C (58F), which was set in 1949. Night-time minimum temperatures were the main contributor to this record breaker. The average minimum temperature across the UK calculated to be 11.5C (53F), which is almost 1C above the previous record of 10.6C (51F), also set in 1949. This record breaking month follows ‘hot’ on the heels of the all-time warmest month on record, which was July 2006. The average daily temperature (both day and night) was 17.8C (64F), and the average maximum temperature was 23.1C (74F)."

Tuesday, October 03, 2006

October began damp and unexpectedly wet for coastal Mahatashtra,and specially Mumbai.The depression 05B fizzled out over interior Maharashtra,but not before dumping record rains over Mumbai.

For Mumbai,the 1st.day of October was wet,thundery and squally.High velocity NorthWesterly gusts swept the city,(anti clockwise movement of the system),and with extremely violent thunder and lightening,the parting monsoon was unleashing all its energy over the city.

On the 1st.,between 08.30hrs. and 20.30hrs.,the city had recorded 81mm and between 20.30hrs. and 08.30hrs. of the 2nd. Mumbai recorded another 114mm.So in the 24hr. period of recording, Mumbai had 194.4mm of rain.This is a record for Mumbai for a 24 hr.period for October.The previous record was way back on 5th.October 1917,when 148.6mm of rain was measured.This is against an average of 65mm expected in October.And all this on the first day of the month.

Coastal areas too had heavy rain.The Maharashtra weather report for 2nd.October gives the rain figures of the other places.Note that the first 10 places mentioned in the rainfall list are on the west coast.

With the system waning now,the monsoon too may start loosing intensity.But there is an odd chance of another system developing in the Bay.It has to be watched initially,though it is likely to move North.

Sunday, October 01, 2006

The month of September over and the rain fall figures are back to normal for the country as a whole. The monsoon has withdrawn from the North and North West only. And West U.P., Haryana, Delhi and the N.East top the rain deficit list. Rest of India is excess or normal. There is an odd chance for the N.East to recover if a low from the Bay recurves and drifts North.

With the Monsoon still active in Maharshtra, the figures are: Mumbai Colaba 2131mm(+106), Santa Cruz 2830 mm (+566), Mahableshwar 8316 mm (+2735), Pune 1104 mm (+550).

With another low expected in the bay by 4th.Oct, we will have to watch its movement to forecast its strenght and course. Only hint we have is that the sea temperature of the bay is now moderate, and is seen here.

Weather forecast from Saturday 13th to Tuesday 16th April - Active pre-monsoon thunderstorm activity across the country The ongoing rain/thu...