Bihar is a very drought-prone pocket, that observes frequent shortfalls during the Monsoon season. Only once in the last 10 years, that’s in 2011, the state had defied this trend and observed marginally above rainfall. Rest on all the other occasions, rains were below normal, of which on nearly 6 occasions the state had seen deficient Monsoon rainfall by more than 20%.
Monsoon rainfall in Bihar in the last 10 years (2009 to 2019):
Talking about this season, the month of June ended on a deficient note with 41%. July did see some significant showers, which helped the state to stand rain surplus at 20%, as per the rainfall data from July 1 to 31. The deficiency came down to zero.
However, August again changed the track and performed poorly to incur a rain deficit of 51%.
This rain deficiency on the first fortnight of September was reversed to the soaking spell in the second half to record an excess of 75%.
Looking at these figures, we can say that Monsoon rains haven’t followed any set pattern, rather it had defied all the previous rainfall patterns. The distribution and pace of rain have been vague this time. There have been more intense spells, heavy to very heavy in nature and a major amount of rainfall was recorded within a short duration.
If we talk in detail, the month of June ended on a deficient note and this deficiency continued until the first week of July. Cumulatively, until the first week of July (June 1 to July 7), rain deficiency was standing at 49%, which happens to be the highest figure for July month.
However, this scenario was changed in the second week of July, wherein flooding rain made an appearance over the state. The good amounts of rainfall covered the deficit rainfall and wiped out the deficiency completely by the end of July.
However, this did not last for long as again in August the state had to battle deficit rains. There had been hardly any significant spells, because of which the state had seen 51% less than the normal rainfall in the month. With this, the state was standing rain deficit at 18 % as per the data from June 1 to August 31.
This situation continued until the first half of September, with deficiency standing at 22% as per the rainfall data from June 1 to September 15. However, the tables were completely turned during the last week of September, wherein extremely heavy rainfall for 5 consecutive days had wrecked havoc.
In fact, in a span of just 5 days, Bihar had recorded 243 mm of rainfall as against the monthly average rainfall of 224 mm. With this, the state had witnessed surplus rainfall by 75% in the month of September.
The heavy rains completely flushed out the deficiency of previous months and as on September 30, the state was standing rain surplus at 3%. (rainfall data from June 1 to September 30). The situation resembles that of the year 2011.
Overall, we can say that the state had battled floods on mainly two occasions. First on July 2 that continued for a week and the other during the last week of September. In fact, Monsoon has not over and done yet over the state, as many districts are still struggling with flash floods, severe waterlogging, with rescue operations going on in a large part of the state.
Although during the last 24 hours, there has been some relief from heavy rains and a similar condition is likely during the next 24 hours as well, we fear that the next episode likely around October 4 may aggravate the situation further.
Although this time rains would occur with lesser magnitude, moderate rains with isolated heavy spells cannot be ruled out. Commencing from October 4, this spell may last for a week, wherein the second part of the week would observe more rains over East Bihar than the western districts.
Already due to heavy amounts of rain, the ground is saturated and there’s no enough capacity for further absorption. The major crops of the state too are bearing the brunt of the flood havoc. While floodwaters are still on the verge of receding, we fear that upcoming showers may worsen the situation further.
Image Credits – DNA India
Any information taken from here should be credited to Skymet Weather