The latest update from IMD[i] on Very Severe Cyclonic Storm VAYU (issued at 0700 hrs on June 13, 2019) does not provide any specific risk of floods in any region, nor does it mention any possibility of persistent rainfall leading to risk of floods.
Another IMD update at 1200 hours on June 13, 2019[ii] says large parts of coastal Saurashtra may experience winds of 160 kmph starting June 13 afternoon, but there is no mention of risk of floods. It does give heavy rainfall warning: “Widespread rainfall with heavy to very heavy falls at few places and extremely heavy falls at isolated places in the coastal districts of Saurashtra” till 0830 hrs on June 15, 2019, in RED colour, the highest risk colour code used by IMD. Further this warning adds: “Flooding of escape routes. Minor disruption of railways, overhead power lines and signalling systems.” Among action suggested it lists: “Inundation of low lying areas along the above mentioned coastal districts due to heavy rainfall and storm surge… Evacuation from low lying areas of the above mentioned Districts, coastal Hutment dwellers, urban slum dwellers and people staying in unsafe house to safer places.” The Ministry of Earth Sciences also sends out these releases through PIB Press Notes as IMD functions under MoES.
IMD’s “All India Weather Warning Bulletin” for 0830 hrs on June 13[iii] too warns of possibility of heavy rains in Saurashtra on June 13 and 14, but Saurashtra, Kutch, Gujarat or Rajasthan does not figure in the list of risk areas for June 15, 16 or 17.
Central Water Commission’s flood forecasting website[iv], the only one in India forecasting floods, has no forecast of floods in Saurashtra or Kutch. In fact, the methodology that the CWC follows (forecasting floods based on water level at any given site crossing certain mark, leading to forecast for downstream sites) would not help. More over NONE of the locations in Kutch Saurashtra or Southern Rajasthan are in the list of CWC’s flood forecasting manual. There is thus no real hope that CWC would be helpful in such a situation.
According to private weather forecaster at 11.25 hrs on June 13[v], Gujarat “remains susceptible to heavy to very heavy rains along with damage potential winds. Areas such as Amreli, Gir Somnath, Diu, Junagarh, Porbandar, Rajkot, Jamnagar, and Dwarka would see widespread rainfall with heavy to very heavy rains. Few places might also see extremely heavy rains today leading to inundation in low lying areas… However, the very severe Cyclone Vayu is going to stay put for at least 2 days over the area before dissipating in the sea only. In this process, Karachi coast would see heavy rains on June 13 and 14. Meanwhile, rain in Gujarat would see a declining trend from June 14 but few places would continue with heavy to very heavy rains.” This is more or less in line with what IMD has said. Again the warnings do not go beyond 14th June.
Accuweather, another website (https://www.accuweather.com/en/weather-news/powerful-cyclone-vayu-to-pass-dangerously-close-to-gujarat-india/70008502) said: “Downpours can drop 25-75 mm (1-3 inches) across western Saurashtra through Friday, threatening to cause flash flooding in some communities. A Local Storm of 200 mm (8 inches) cannot be ruled out in the most persistent downpours.”
However, if we see another website, ventusky.com, we get a very different picture. The following screenshots from the prediction of rainfall due to VAYU shows that due to prolonged exposure of moisture laden winds, there is possibility of continued rainfall along coastal Saurashtra, Kutch and South Rajasthan, that may extend upto June 18. The predictions are available every three hours, but we have taken the screenshots for 11.30 am and pm on June 13 and 11.30 pm for June 14 to 18.
It seems from these screenshots that there is real possibility of heavy rainfall along coastal Saurashtra, Kutch and Southern Rajasthan that would extend beyond 14 June that IMD, Skymet and every other available forecasts are available and it may also result in flooding. The rains in these areas are welcome, but damaging floods are certainly not. Hope this helps creating better warning and preparedness and also reducing the possible damages. One also hopes that India’s flood forecasting capabilities become more accurate, advanced and specific.