Monday, April 30, 2018

Posted Monday 30th April:

In Pakistan, Nawabshah records 50.2c, Jacobabad 50.1c, Pad Idan 49.1c on Monday 30th April...so Nawabshah 50.2c is new Asia record for April.

(On 19th April 2017, first ever 50.0 c temperature in April in Asia has been recorded at Larkana (Sindh).


Sunday, April 22, 2018

Monsoon Watch - 2...2018 ....22nd April
Further Analysis of the parameters as discussed in MW-1... 

Position as on 21st April :
1.Cross Equatorial Winds:
Let me explain, that the winds on crossing the equator break into 2 branches. i) gushing into the Arabian Sea, and ii) moving into the Bay of Bengal. 
Normal April Winds





Current Winds


During Monsoon Watch 1 , the cross equatorial flow was not at all organised.

i) The cross equatorial wind flow, has yet to organise  up in the Western sector Southern Hemisphere. Winds, have not yet in the required SE direction off the East African Coast. The Northwards movement of the ITCZ will surely hasten and strengthen the winds.

ii) In the eastern sector, in the Bay Branch, the Cross equatorial winds are not organised Westwards towards the Sumatra Coast. Twin Lows at 5N and 5S above and below the Equator between 80E and 90E are kepping the cross flow winds dis organised. The winds hitting Sumatra coast are not Westerly (as required), and also need to gather strength soon.

And that is exactly where the start should be for the SWM to arrive at the Andamans. Upper winds at 100-400 hpa have just about vigorously starting in aiding the lower winds to attain the required direction and strength.

We prefer the Bay Branch to be better organised, as the SW Monsoon is normally expected there in 22-25 days…

Mascarene high pressure zones in the South Indian Ocean. Main High reading now 1027 mb and another one at 1018 mb has been observed between Madagascar and Australia.


The "Power House" of the Monsoon winds is slightly behind schedule, for this time of the season. But it is expected to strengthen fast with no tropical storms around.Hence would hasten the Cross Equtorial Wind flow.
Indicator : -ve

2. Seasonal Low: 
No meaningful Heat wave is currently observed in the Sub Continent. By Heat waves, we mean temperatures over 5-7c above normal..not the normal heat.


The core low formation region(Thar desert/Sindh) has heated up normally this summer . The highest in the region of Thar /Sindh/Rajasthan has been around 44c, and Vidharbha Chandrapur just about touched 45c on 18/19th April.
See the 7 days Max temperature annomolly 

In 2017, Barmer had approached 46 c and recorded min temp above 30 c. April heat records had tumbled at many locations in the subcontinent. On 19th April 2017, first ever 50 c temperature in April in Asia has been recorded at Larkana (Sindh).
Temperatures of more than 45 c had already been recorded in many states of India . Even at Srinagar (Kashmir),Shimla (Himachal) temperatures  approached around 29 c in April 2017 . Delhi AP was 44.9 c on 20th April 2017.

Last year , in 2017,  Most of India was in the 4-7c above normal range and pockets shooting to 15 c above normal ...

Earlier than normal,the night temperatures had also crossed the 30c mark ! Barmer in Rajasthan recorded 30.4c as minimum on 15th April ,Kurnool (Andhra) saw a low of 31 c on 19th morning and Jhansi (UP) saw a low of 31.6 c on 21st morning.
Jaipur,Kota,Bundi,Alwar,Bikaner,Churu,Pilani (Rajasthan), Cuddapah(Andhra) saw lows of/above 30 c on 21st April 2017 morning.

Comparison with previous years shows the difference this year. In 2010, the first 45c touched on 10th. April, and on the same day Nagpur was 44c, Delhi 42.8c. Soon on 15 th April 2010,  Nawabshah (Pakistan) soared to 47c, Simla to 28.2c on 16th, Ganganagar, Akola and Hissar to to 46c. 

But, in 2011, 2012, 2013 and 2014, till date, temperatures were  yet to reach 45c anywhere in the Sub-Continent . 

2015...Into the 3rd. week of April , we had seen 48c in Pakistan on 19th April in Larkana,and 46.5c in Moen Jo Daro. In India had just topped 44.6c in Barmer on 19th April.

2016....touched 46c in Bankura on 16th April...and was constantly hot in Eastern region with almost daily ,a place touching 46c.. Bhubaneshwar and Titlagarh in India and Dadu in Pakistan had touched 46c. Several large regions in Vidharbh, Telengana and MP were in the 44/43c range.

The seasonal Low, as a result of nominal heating, is shaping up "casually". It has shown slow progress after MW 1 when it was 1008 mb.

Last 2 days, the lowest pressure, in the core (Thar Desert) region was at 1006 mb.(Last year 998/1000 mb). (In 2011/2014 was 1006 mb, 2010/2012 was at 1002 mb this time. 2015/2016 it was at 1000-1002 mb). 
IMD Chart:
Lows over MP, Central India, should become less conspicuous because of the strengthening of the seasonal low over NW India.

As mentioned, it normally should reach a low nadir of 994 mb in June in the Thar Desert, and with 1008mb in the South Arabian Sea, a perfect gradient is created to attract the south -west winds towards the coast.

Thunderstorm activity in Southern Tibet is seen to be picking up. 



The Line of Wind Discontinuity should normally stabilise around Central India perpendicular down into the Southern Peninsula by mid April. 

This enhances the speed of the Seasonal Low formation. Normally is required to start taking shape for the monsoon by the second week of April.
LWD (trough) is currently near the Central-Southern region of the Peninsula…running roughly from Madhya Mah/Marathwada thru Karnataka towards the Kerala Coast. 
Pre –monsoon thunderstorm activity is seen in Interior Mah, Int  Karnataka and Kerala. Some activity seen in patches along Coastal A.P. and Odisha…..after  MW 1 release.

In reality, this LWD ( full formed) remains till June, in variable phases, and finally merges with the Monsoon trough (axis)/ITCZ  when the ICTZ moves towards the Sub Continent.
Indicator: -ve

3. ENSO: This year also, like last year, we also base our observations on the Multivariate ENSO Index (MEI).  An attempt is made to monitor ENSO by basing the Multivariate ENSO Index (MEI) on the six main observed variables over the tropical Pacific. 

These six variables are: sea-level pressure (P), zonal (U) and meridional (V) components of the surface wind, sea surface temperature (S), surface air temperature (A), and total cloudiness fraction of the sky (C). (Negative values of the MEI represent the cold ENSO phase, a.k.a.La Niña, while positive MEI values represent the warm ENSO phase (El Niño).The MEI is computed separately for each of twelve sliding bi-monthly seasons (Dec/Jan, Jan/Feb,..., Nov/Dec). 

Negative values of the MEI represent the cold ENSO phase, a.k.a.La Niña, while positive MEI values represent the warm ENSO phase (El Niño).

The updated (Mar/Apr) MEI is at -.502 (in Feb/Mar was -0.731), for a slightly decreased ranking.

SOI rises Sharply from =6.0 in February
30 day SOI has risen , and is now at  10.5 ( SOI of -7 to 7 is neutral. Above 7 is La Nina, and below -7 is El Nino ).

The Oceanic Nino Index (ONI) is based on SST departures from average in the Niño 3.4 region, and is a principal measure for monitoring, assessing, and predicting ENSO. After 5 overlapping seasons showing towards establishment of La Nina, we see a neutral turn. ONI latest is -0.77... ( ONI of -0.5 to 0.5 is neutral. Above 0.5 is El Nino, and below -0.5 is La Nina).
Indicator: heading towards Neutral.


4. The Bay has yet to host a pre monsoon low during  April. BB-1 had formed way too early in March.
As discussed, we should normally see a low sometime after the 15th of April. The high pressure region in the Bay, at sea level, no longer prevails. 

A strong MJO would hasten the favourable formations and lows, with enhanced precipitation. But the MJO, it seems will remain stalled (without eastward propagation) for the next 10 days .
Hence, not much progress is expected on this front during the next 10 days.

Another factor, which helps the winds gain strength, and bring more moisture into the Indian landmass, is the sea temperatures on both sides of the Peninsula. Optimum (warm) temperatures will hasten and create more clouds, and help in faster forming of the lows from the Bay. Currently , the sea temperatures on both sides of the Peninsula are normal/below normal.



We prefer the Bay parameters to show progress faster , as the SW Monsoon is expected there in 22-25 days…
Indicator: -ve

5. To bring the existing SE winds above the equator (as SW), the ITCZ should move northwards. Around 1st. of May, this should cross the equator. The ITCZ should now come back to its Northward position, as the effective "Lows" created by the Rossby Wave are reducing. 
ITCZ is just south of the equator (1 s).
Indicator: Normal


So, overall, we can summarise as:
Parameter:    1) -ve   2) -ve  3) Neutral   4) -ve   5) Normal.

Summary : Three parameters is -ve as of today . Parameters have not improved compared to MW 1 .
We will put up the estimated date of arrival in the MW-3.

But, situations can change fast, and by the time we discuss the next MW, some factors can suddenly become +ve or -ve. So, MW discusses and follows the developments as they emerge, and discuss the parameters as is where is. 

No model can commit  today when the Monsoon can arrive. 
Quantum of rain forecasting in April for June right through September is an impossible task. Things get clearer by last week of April. Vagaries' (in MW) normally remains true to estimates around early May. 

Next MW up on 3rd May with Dates of Monsoon Arrival.

Thursday, April 19, 2018


Posted Thursday Night 19th April

Arctic Sea Ice Volume Surges 3 TRILLION Cubic Meters Since Early March!


Media claims of “unprecedented” sea-ice melt in the Arctic are just simply not true.
Using data from the Danish Meteorological Institute (DMI) for a comparison, Japanese skeptic blogger Kirye at KiryeNet drives home how “the real Arctic sea ice volume is much higher than in 2008.”
It totally defies the panicky claims of a “melting” Arctic, she tweeted.
Here’s a screen shot from April 7th of this year. Note that sea ice extent is far, far greater than at the same time in either 2017 or 2016.
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Sunday, April 15, 2018

Posted 15th April Sunday :
Some parts of NW India had above normal temperatures on Sunday...But no heat waves as such. 



Compare this with the report of 19th April 2017..below
"Heat wave is currently on across North, Central,Western India.
The core low formation region(Thar desert/Sindh) has heated up early this summer . Barmer has approached 46 c and recorded min temp above 30 c. April heat records have tumbled at many locations in the subcontinent. On 19th April 2017, first ever 50 c temperature in April in Asia has been recorded at Larkana (Sindh).
Temperatures of more than 45 c have already been recorded in many states of India . Even at Srinagar (Kashmir),Shimla (Himachal) temperatures have approached around 29 c in April . Delhi AP was 44.9 c on 20th April 2017.

The current temperature anomaly. Most of India is in the 4-7c above normal range and pockets shooting to 15 c above normal ...
Earlier than normal,the night temperatures have also crossed the 30c mark ! Barmer in Rajasthan recorded 30.4c as minimum on 15th April ,Kurnool (Andhra) saw a low of 31 c on 19th morning and Jhansi (UP) saw a low of 31.6 c on 21st morning."

Minimums this year, 2018,  (on the higher side) is around 26/27c. Maximum Have not crossed 43/44c as yet anyplace in the Sub continent.

Friday, April 13, 2018

Posted Friday 13th April:
For the follow up of the development of the Seasonal Low and consequently the cross equatorial winds, we are observing the temperatures across the sub continent... No major Heat waves seen ...But Core Seasonal Low seen at 1004 mb...(Please see April 14th & April 17th Vagaries Posts of 2017 to compare last year's Heat to this year [as yet])








Mumbai will be partly cloudy this weekend. Days will be around 34c and night 23/24c. 
Pune also will be partly cloudy with days rising to 38c and nights around 20/21c.

Tuesday, April 10, 2018

Monsoon Watch - 1... 2018....10th April 


These reports are my personal views, study and observations. Estimates and forecasts are also my own calculations and views, and may/may not tally with any other estimates. This may not be used for commercial purposes. The author is not responsible for any commercial loss from this article, or this series of articles.

The Monsoon developments, as they unfold, will be analysed and discussed and explained in Vagaries. 

The South West Monsoon is just about 35 days away from its normal date of arrival from the shores of India ! Yes ! its just 35 days from the First touch of shores...Southern most point of India on the South Andaman Islands, Indira Point, where the normal arrival date is 15th May.
And its about time we start the follow up of its progress and monitor its developments. 

The Sub-Continent is eagerly awaiting its share of 2018 monsoon rains !

This annual series is a follow up and chasing of the South-West Monsoon. 

Every article in this series explains the synoptic situation as it actually is, and based on the day's position, the date and quantum of rains as on THIS CURRENT SITUATION.

It is very important to firstly estimate the date of arrival of the S W Monsoon, as year to year, variations in dates of onset of the monsoon can occur and there have been several occasions in the past when the monsoon arrived over certain parts of the country about a fortnight earlier or later than the normal dates. The SWM has the  weatherman tearing at his hair for the exact date or time, extent and progress. This is never 100 per cent sure though various weather models are used to calculate this event.
Initially, in the first few articles, of this series will be chasing and closely following up the actual developments of the monsoon parameters, and analysing its progress regionally for calculating and estimating the arrival date. 

We are not yet contemplating the quantum of rains or the monsoon strength as yet. 

There are 2 parts to this article:
A)-This is the Ideal Conditions  During SWM Onset in Early June.  


and 
B)below indicates the actual situation of the parameters situation today (9th April).

A)
Very very briefly, let  us first understand, that the "power house" of our SWM is actually based far away in the southern Hemisphere. The main "generating factory" is the Mascarene Highs, between SE of the Madagascar coast and Australia. The SWM is born down South, 4000 kms from the Indian Mainland !

The proper formation of these high regions,(1032/1034 mb at least) will boost and create proper SE winds to lash the East African Coast near the Equator, and then turn perpendicular towards SW in the Northern Hemisphere. 

And the formation of the "Tibetan High" is another factor. An anti-cyclone in the upper atmosphere over the Tibetan Plateau. During the formation stages, there will be thunderstorm activity in the SE parts of Tibet during the months of April and May.

To generate a powerful SW wind, the cross equatorial flow must be strong and gusty. SW winds (ultimately upto 600 mb levels) then are capable of riding on the warmer Arabian Sea waters (Arabian Sea Branch of SWM) and bring cloud masses towards the West Coast of India. In the Bay, similar SW winds are generated (Bay branch of SWM), but from SE winds below the equator, just below Sri Lanka.

And to attract the SW winds, again, we need a good proper "seasonal low" to develop in the Sub-Continent. This seasonal low, normally should start forming around Barmer, Rajasthan, by mid April, and at its peak stretch upto Arabia. Seasonal low at its peak, in June, should normally be around 994 mb, and the ridge around Kerala should be 1008/1010 mb. This enables a good gradient to pull the SWM Northwards and inland.

B)-In this initial stage, we will observe the basic root and foundation, the initial 4 parameters only, and the initial seed of the monsoon. From these parameters, later a few more develop.
1. Cross Equatorial Winds from Southern Hemisphere.
2. Seasonal Low over India/Pakistan.
3. ENSO Status.
4. Pre Monsoon Low in the Bay.

Position as on 9th April:
1. Cross Equatorial Winds:
The Mascarene Highs are the main "Power House" of the South -West Monsoons. This generates the South -East winds, which after gaining strength, cross the equator and become south west. For a proper High to form in the South Indian Ocean, the cyclone season (Low pressures) should completely die down from that region.

As on date today, the Mascarene Highs is forming in the required region. A small High at 1031 mb.  Four "weak" Lows are tracking in the region. We have to wait for these "lows" to dissipate.


But things are unorganised  below the Equator.( Wind Chart Below)
Cross Equatorial Winds should start forming, and taking shape from mid -April, especially in the South Indian ocean region. 
Initial forming of SE winds off the East African Coast has not started from below the equator. Weak  Easterly  flow below Sri Lanka (in the Southern Hemisphere) can be see, though a bit dis-organised.


ITCZ:This Seasonal trough passes from the South  Arabian Sea to Andaman sea after the withdrawal of SWM in Oct. Shifts further south in Dec. Moves North during SWM
Now near the equator.

Today, the winds  North of the Equator are Northerly (around a "high") in the Arabian Sea, ... and are Easterly in the  South of the Arabian Sea. 
As the Monsoon strikes the Andaman Sea by mid May, developing wind currents ( Westerly) are required to be observed initially near the Eastern side of the Southern Indian Ocean, and this is not  forming as of today, Southerly flows are required to strike Sumatra.

Indicator: -ve

2. Seasonal Low: Now, this year, the heating in the sub continent has started from March , with  Heat Waves in Maharashtra, Gujarat, Central India and parts of NW India.. The above normal heating in many parts continues in April. 
On an average, March has registered normal temperature (average day and night),  

and, with below normal rainfall...-48%. These are a points in the formation, or a quicker formation of one of the important pre monsoon weather requirement, the seasonal low.


In June,the seasonal low, which stretches to Arabia from India, normally starts forming in the Barmer and adjoining regions in the second week of April. 

Today, the MSL is around 1008 mb in the North Rajasthan/Sindh region. There is a isobar of 1010/1008 mb covering almost the entire Indian region. In the "core seed" area, it is 1006 mb. (The ultimate low in the core, in June when ready, should be 994mb.). This progress is bit tardy. 


The current Line of Wind Discontinuity (weak in S.Madhya Mah Region) should stabilise around Central India perpendicular down into the Southern Peninsula. This enhances the speed of the Seasonal Low formation. Normally is required to start taking shape for the monsoon by the second week of April. 
Indicator: -ve

3. ENSO is on way to a Neutral Stage. 
This year also, like last year, we also base our observations on the Multivariate ENSO Index (MEI).  An attempt is made to monitor ENSO by basing the Multivariate ENSO Index (MEI) on the six main observed variables over the tropical Pacific. 

These six variables are: sea-level pressure (P), zonal (U) and meridional (V) components of the surface wind, sea surface temperature (S), surface air temperature (A), and total cloudiness fraction of the sky (C). (Negative values of the MEI represent the cold ENSO phase, a.k.a.La Niña, while positive MEI values represent the warm ENSO phase (El Niño).The MEI is computed separately for each of twelve sliding bi-monthly seasons (Dec/Jan, Jan/Feb,..., Nov/Dec). 

Negative values of the MEI represent the cold ENSO phase, a.k.a.La Niña, while positive MEI values represent the warm ENSO phase (El Niño).

The updated (Feb/Mar) MEI has changed to -.502 (in Jan/Feb was -0.731), for a slightly decreased ranking, now moving towards neutral stage. 

SOI is falling, and is now at  + 12.4.
Sustained positive values of the SOI above +7 typically indicate La Niña while sustained negative values below −7 typically indicate El Niño. Values between +7 and −7 generally indicate neutral conditions.

The Oceanic Nino Index (ONI) is based on SST departures from average in the Niño 3.4 region, and is a principal measure for monitoring, assessing, and predicting ENSO.  ONI latest is -0.9... Just marginal, could get lower in the coming months...But at this stage, it cannot be surely mentioned, that an neutral stage could fully develop by June, the onset time of our South West Monsoon.
( 0.5 - -0.5 is neutral. Above 0.5 is El Nino, and below -0.5 is La Nina).
La Niña conditions are present.
* Equatorial sea surface temperatures (SSTs) are below average across the central and eastern Pacific Ocean. A transition from La Niña to ENSO-neutral is most likely during the March-May season, with neutral conditions likely to continue into the second half of the year.
Indicator: Heading towards Neutral.

4. Another pre monsoon seasonal normal requirement is the creation of an initial low in the Bay by the second week of April. This is necessary to trigger off the flow and formation of lows from the bay.
Progress this year is bad, (With BB-1 having already been formed prematurely) as the Bay shows no signs today. No forecast of any low as of now. (in 2009,a low formed by the 12th. of April, and later it intensified into cyclone "Bijli", 2010 had no low till 3rd week of April).
Today, we have East winds in the Bay. The required SW winds may not yet form at least for the next 4/5 days.
Indicator: -ve

Summary for arrival Date: Parameter 1). -ve   Parameter 2). -ve,  Parameter 3). Neutral Parameter  4). -ve.
Summary: Tilted towards slightly Negative, as of 10th April. Parameters analysed as of now show slow progress for Monsoon Advance on time.


New Readers, please note, These initial Parameters are normally (every year) considered in MW Series to gauge and estimate the arrival date of SWM, not strength. Time of arrival normally indicated in MW-3, and strength after 27th April. There are more parameters are to be considered, as and when they are developed and to be taken into consideration.

MW-2 on 22nd. April.

While IMD still defers its forecast, IMD should have taken up this job in right earnest much earlier. Vagaries had mentioned this earlier here.. http://rajesh26.blogspot.in/2012/03/importance-of-monsoon-forecast-for.html....March 19th 2012

Sunday, April 08, 2018

Monsoon Watch-1, Vagaries' annual Monsoon Chase and follow up, will be published on 10th April ( 11 pm IST)....on Due date !

Thursday, April 05, 2018

Posted Thursday 5th April Night:

Weekend Forecast:

Mumbai: Friday will be partly cloudy. Clouds forming by afternoon.
Saturday will be cloudy. Light rains possible in parts of city. Cooler day time temperatures but warmer night.
Sunday will be partly cloudy and windy.

Pune: Rain, light to moderate , expected on Friday and Saturday. Saturday will be windy with light rains. Sunday also will be cloudy with light rains.




Tuesday, April 03, 2018

La Nina is Doomed

It has become increasingly clear that our current La Nina is doomed and that next winter we will probably be in a Neutral or "La Nada" situation.  Maybe even a weak El Nino.

As you will remember, La Ninas are associated with cooler than normal sea surface temperatures in the central and eastern tropical Pacific.  Here are the temperatures for the Nina 3.4 area that meteorologists love to use as a key marker of La Nina/El Nino activity. Blue indicates colder than normal.   Still in a La Nina.

La Nina's are generally associated with high pressure out in the eastern Pacific and cool/wet conditions over the Northwest, particularly after the new year. And we have had that situation in spades the last month.

Here are the anomalies (differences from normal) for the heights (like pressure) at 500 hPa (around 18,000 ft) for the past month.  A trough over us (blue colors) and a ridge (red colors) south of the Aleutians.  This pattern is why we have had so much snow the last month or so, since the cool, wet trough is favorable for mountain snows in our area.

But things are changing.  The cold water in the Pacific is being eroded from below as warmer water moves in.  This figure shows the heat anomaly (difference from normal) under the surface at the equator.  It is now warmer than normal beneath the surface.  The grim reaper for La Ninas is preparing the final end.
Various groups run prediction models for La Nina and El Nino, using both full physics and statistical approaches.  As shown in the following figure, nearly all the models show a weakening of La Nina (with temperatures going form below normal to near normal...or even above normal).  At the very least that implies Neutral (or normal conditions).  And maybe even a weak El Nino for next winter

The Climate Prediction Center even gives probabilities for the upcoming months.
They suggest we will rapidly go into Neutral territory by late spring and stay there into early next winter, with a nearly equal chance of being in a weak El Nino.

Article Courtesy: Cliff Mass Weather and Climate Blog

Monday, April 02, 2018

Posted 2nd April Monday:

As mentioned on 11th  March in this blog, after the initial rains we had also mentioned more rains in April:
"2nd week April will see good pre Monsoon Thunder Showers in the Interiors of Maharashtra and Interior Karnataka."

Rain or thundershowers are possible in North and South Madhya Maharshtra and N.I. Karnataka on 6th and 7th April. 
Pune and districts in Madhya Mah. and Marathwada can expect thundershowers on the 6th and 7th. Hot days on 3rd and 4th April in Madhya Maharashtra.

Mumbai: Thunder clouds can drift over Mumbai, over parts of Mumbai on 7th April. Light rains possible.

Mumbai Water Supplying Lakes Position as on 2nd April 2018:
Lake Levels in Metres with overflow levels in brackets.
Modak Sagar = 154 (163)  Tansa  122.94 (128.63 ),  Vihar  76.98 ( 80.12),  Tulsi    135.47 ( 139.17),  Upper Vaitarna   597.05  (603.51), Bhatsa  122.6 (142),  Middle Vaitarna   278 (285).

Thus the total supply available is approximately 670 Mcum. At 4 Mcum /day consumption for Mumbai , The city has approximately 5.5 months available stock.
Lakes Information : Courtesy Vagarian Jayesh Mehta

Posted Wednesday Morning With the arrival of J-4 by 19th, and which is fairly intense, we can expect widespread rain/snow in the North. N...