The last leg of Mercury-Venus closeness in 2023 started late on 23rd December and is due to end on 26th February 2024. Generally, such a closeness period is said to bring rainfall but in non-rainy season starting from the end of December and January, this closeness is found to be associated with very cold days and dense fog. The rain from Western Disturbance is also realized in this period. Of these features, the occurrence of fog is a garbottam factor indicating rainfall later.
The dense fog for prolonged hours and repeating for many days, in my understanding, could result in cloudburst causing severe damage to life and property. Therefore, I decided to document this year’s foggy days and cross check whether this brings devastating rainfall later.
Let me reproduce the table of Mercury- Venus closeness for the year Shobhakrit (2023-24)
The last row shows the closeness period in late December that is going up to the end of February. Expectedly this period witnessed intensely foggy days in North India and in Chennai too.
The IMD report says that dense fog which was witnessed in isolated regions in Punjab and on 21st and 22nd December 2023, started to appear in most of the places of North India by the 23rd of December, the day the closeness of Mercury and Venus started. The intensity was high on 26th and 27th December.
Click to access 20231228_pr_2720.pdf
Once again, the 30th and the 31st of December witnessed severe fog.
30th December 2023
31st December 2023
Incidentally, these days were almost like the days mentioned by Lakshmana in Valmiki Ramayana, on the morning of a day in Hemanta ritu (Margashira and Pushya / Margazhi and Thai) while he along with Rama and Sita was walking towards the river Godavari on a pre-dawn morning. In that talk, Lakshmana described the dense fog in the night that was getting over. In that context he talked about the rise of the star Pushya after sunset and how the sky was blanketed with tawny dew that the Pushya star could not be seen as though it had gone to sleep. After it reappeared from the dew cover, the chillness continued for three Yaama by which time the pre-dawn was set and the three were walking to the river.
The verse is given here:
निवृत्त आकाश शयनाः पुष्यनीता हिम अरुणाः |
शीता वृद्धतर आयामः त्रि यामा यान्ति सांप्रतम् (3-16-12)
This can be illustrated as follows:
Pushya is in the sign of Kataka (cancer). In the month the sun rises in Sagittarius (Margazhi), the sunset will be in Gemini (Mithuna). If the sun was in the middle of Sagittarius, say at 15th / 16th degree (30th and 31st December), the sunset will happen after around ten and a half hours at the beginning of Gemini (due to shorter days) and Pushya will rise 33 degrees after sunset, i.e., well after 2 hours after sunset.
Two hours after sunset fog started enveloping the sky. This was stated by Lakshmana by the description of Pushya star going into sleep. After some time, the fog cleared but chilly weather continued for three Yaama-s. The Yaama gives the clue that there was indeed foggy weather in the early part of night some time after sunset.
One Yaama is equal to 2 hours and 24 minutes. Three Yaama-s make 7 hours and 12 minutes. Assuming that the sunset was around 6 pm in their location in Panchavati, Pushya must have risen after 8 pm. But by then it became foggy. Assuming that the fog cover was seen from 8 to 10 pm when Pushya’s sign of Kataka was rising, it is indicative of Mun-pani season, i.e., early night fog. It would clear soon, and the night would continue to be cold. Suppose the early night fog cleared by 10 pm, then for the next 7 hours and 12 minutes there was chill weather. By 5-30 am, it was pre-dawn and Lakshmana, Rama and Sita had woken up and started walking to the river. On this walk, Lakshmana was describing how foggy it was that they could not see Pushya rising and how cold it was for the rest of the night.
Similar kind of foggy night and chillness was experienced throughout North India on the days when Pushya was rising two hours after sunset. I could not help thinking about this verse when those foggy nights were reported by IMD and many news outlets.
“There were 20 days in these two months (December and January) when a dense layer of fog covered the Capital. In 2014-15, there were 174 hours of dense fog, while in 2013-14, it was 160 hours,” said RK Jenamani, scientist at IMD. In January 2024 alone, according to IMD data, there have been 14 days of dense fog, with about 88 hours of recorded fog, reported Hindusthan Times.
Very dense fog started after midnight and continued till 9-30 am on some days. In December such dense fog was reported in Northwest India but in January East and North Indian States and the Himalayan and sub-Himalayan regions were covered in fog for long hours. These days are to be counted as Garbottam days with potential to cause heavy rainfall from cloudburst and landslides in the Himalayan regions (or vulnerable regions).
When I checked the two years mentioned in the above report from Hindusthan Times, the corresponding month in 2014 did see cloudbursts in Uttarakhand and landslides in other places. For 2015, I don’t have data.
The corresponding dates of rainfall for certain foggy dates of 2023-24 noted in the IMD report:
23rd December 2023 – 2nd July 2024
26th December 2023 – 5th July 2024
30th December 2023 – 8th / 9th July 2024
31st December 2023 – 10th July 2024
Most days in January were foggy, extending the heavy rainfall period throughout July in those parts where fog was reported.
Interestingly, daily garbottam for Chennai showed continuous rainfall almost throughout July.
That assessment will be posted next.
PS: The above observation on fog is in theory. This year being foggy for many days and with greater intensity, this data is taken as test case. If it tallies with the results, this will be considered as one of the main factors for predicting cloudbursts, landslides due to intense rainfall.
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