Saturday, November 22, 2014

RAINFALL CLASSIFICATIONS IN INDIA

FORECAST CATEGORY [IMD LEGEND]

1. WIDE SPREAD                          (most places)               76 - 100 %

2. FAIRLY WIDE SPREAD           (few many places)        51 - 75%

3. SCATTERED                             (few places)                 26 - 50%

4. ISOLATED                                 (one or two places)     01 - 25%

24 HOURS accumulated rain means rainfall accounted from 0830 hrs IST of today to 0830 hrs IST of tomorrow.  That is rainfall ending at 0830 hrs IST [03Z] of date.
The rainfall is reported in mm correct to first decimal. Standard raingauge in India is Fibre glass reinforced Polyester type raingauge of diameter=159.6mm [collector area =200 sq.cm] with relevant measure glass 20mm

[a] heavy rainfall      ::::::::::::::: Greater than or equal to  65.0 mm

[b] very heavy rainfall :::::::::::Greater than or equal to  125.0 mm

[3] extremely heavy  ::::::::::::: Greater than or equal to  250.0 mm