Before going further, lets see the last two years August Rainfall in Coastal Karnataka and Kerala
Coastal Karnataka (Normal 756 mm)
2018 – 925 mm
2019 – 1376 mm
Kerala (Normal 420 mm)
2018 – 822 mm
2019 – 951 mm
As you can see how massive the rainfall was in the August month in the last two years and particularly the 2019, the rainfall shifted from drought to excess rainfall in such a short period and most of the dams started overflowing. The ghat areas of Idukki, Wayand, Kodagu, Chikmagalur, Mallapuram, Thrissur, Valparai, Nilgiris all rocked. Coming to 2020, the rains are poor till now in the above districts till now like 2019. But this is all going to change this August too with 1st proper low forming refer the windy map of 850 mb winds used for explanation.
Till date not even one single low pressure has formed in the core monsoon region and this is the 1st low pressure area which formed in North Bay and then moves into core monsoon zone. It will be followed by next low pressure in the 2nd week of August. Whenever a low forms the otherside and moves inland from Bay of Bengal via Odisha->Madhya Pradesh->Mahrashtra->Gujarat, this activates the monsoon winds in Arabian Sea side and creates strong offshore trough. The first low pressure lasts till 8/9th August followed by next low pressure which forms immediately.
1. Interior Tamil Nadu – Windy days ahead and reduced Veppa Salanam rains
When monsoon gets active, the Veppa Salanam rains in leeward side will reduce but with strong surge sometimes the clouds cross the mighty western ghat mountains and have given rains to dry places of Coimbatore, Erode, Palyamkottai and other areas close the mountains. You can see thee mighty monsoon winds is coming via palghat pass and some through the Sencottah pass. The winds also pass through Gulf of Mannar the other side. This means it will be super windy in coming days in Tiruppur, Karur, Erode, Namakkal, Thanjavur, Trichy, Nagapattinam etc and down south Madurai, Tirunelveli, Thoothukudi, Ramanathapuram, Sivagangai will all be super windy for 1st time this monsoon. There will be some veppasalanam rains here and there but it will be isolated ones.
2. One week of Continuous downpour ahead in West Coast / Ghats
Kerala
Starting from tomorrow, Idukki, Wayand, Mallapuram, Palakkad, Thrissur, Eranakulam, Kannur, Kasargode and Kozhikode needs to be in high alert and peak rains will happen between 5-8th August. These 4 days one should be in very high alert. Coastal belt will get rains too but this time the mountain Ghat will outshine the rains in coast.
- Peermede, Thodupuzha, Pambla Dam and Ponmudi in Idukki,
- Nilambur in Mallapuram
- Kuttiyadi and Kakkayam in Kozhikode
- Thariode, Vythri and Padinjarathara in Wayand
- Kakki Dam, Poringalathu and Lower Sholayar in Thrissur
- Neeriamangalam and Piravom in Eranakulam
Tamil Nadu
In Tamil Nadu, Nilgiris and Valparai will be the hot spot for rains for next one week.
- In Nilgiris – areas such as Pandalur, Devala, Gudalur, Naduvattam, Avalanche, Upper Bhavani, Parsons Valley, Mukurthy and Porthimund will get heavy rains.
- In Valparai – the areas such as Valparai Town, Sholayar, Chinnakallar, Lower Nirar, Upper Nirar, Manomboly and Cincona will get heavy rains. Pollachi will get moderate rains.
- In Theni – the rains will be confined to Periyar Dam-Thekkady belt. Other areas it will be light to moderate spill over monsoonish rains.
- Kanyakumari – Upper Kodayar belt will get heavy rains. While other areas such as Pechiparai-Perunchani
- Thenkasi will get moderate rains and there will be good flow in coutrallam falls.
- Nearby district such as Tiruppur and Coimbatore areas will get moderate when clouds cross western ghats.
- Chennai and KTC will get fast moving rains and we need to wait till next week before the next low forms for Damal Dumeel rains. Till then there will be chance for isolated fast moving rains. And windy days ahead.
Karnataka
- In Kodagu – Talacauvery, Bhagamandala, Naladi, Surlabhi will be the hotspots.
- In Chikmagalur – Kottigehera, Kerekatte and Kigga will get super rains.
- In Shimoga – Agumbe, Hulikal, Mastikatte, Yadur, Cogar, Megarvalli, Nagavalli and Nagara will be hotspots.
- In Udupi – Kollur belt will be the hotspot
- In Belgaum – Khanapur taluk will rock with rains in Amagaon, Gavali and Kanakumbi
- In Uttar Kannada – Nilkund, Gokrana, Castle Rock, Anasi and Gersoppa will rock.
- Other district such as Mangalore belt in DK, Hassan region of Sakleshpur will rock.
3. Mettur Dam
With massive rains expected in cauvery catchment areas of Kodagu and Wayand, the dams in Karnataka will get huge inflows. Kabini and Harangi will get filled up in 1st few days and by mid-august all dams will be full and huge water will released to Mettur Dam. So great days for Cauvery belt. The model output show, huge inflows with a once in 20 year event. Lets see how it unfolds.
