--This is no news flash to anyone following the story of a would-be Arabian Sea cyclone. It became clear late last week that this was not going to happen. It took some time for the foremost cause of this none-happening to show. The culprit? A "Western Disturbance," which is another name for a short-wave trough in the westerlies. Anyways, this western disturbance was not indicated at the time that numerical forecast were showing a tropical cyclone (low) off western India., which is consistent inasmuch as the northern system (of the strength it happened to be) would be expected to preclude a tropical cyclone over the northern Arabian Sea.
The western disturbance that blocked any Arabian Sea cyclone dipped out of Afghanistan and into Pakistan during the weekend. In so doing, it set up southerly steering wind flow over much of the Subcontinent. Enter a tropical wave drifting west from the Bay of Bengal. The shift to southerly steering winds veering this wave northward along a path to the east of the Western Ghats.
Ironically, the western disturbance was the spark for rain in Pakistan rather than any tropical low, but the rain happened far to the north as thunderstorms along the northern edge of the plains. As had been forecast, offshore wind flow and blazing sun put Karachi on the "hot plate" with four-straight, 100-degree days. Hottest were Friday (107 F/41.8 C) and Saturday (106 F/40 C).
-Rain-wise, India did well by this tropical weather system. Indeed, "too well" in areas of Karnataka that were swept by major flooding unleashed by its rain. There was an unbroken swath of heavy to very heavy rain across the mid-south of India, especially over Andhra Pradesh and Karnataka into Maharshtra. Kurnool, Andhra, was hit hard.
Now, with the tropical wave winging northward for the Himalaya, Mumbai has picked up 16 cm of rain within 48 hours. All of October has had, on average, only about 6 cm. Also doused during the last few days have been areas of Madhya and Uttar (14 cm at Agra).
-Looking forward, the word for the Subcontinent is that "it is not over" -- yet. The tropical wave is slowly tracking towards the north and the northeast. The steamy tropical settle that surrounds the wave (still a part of the SW Monsoon, I would say) will help to instigate further local heavy to very heavy falls between north-central India and the middle and eastern foothills. The last of the heavy rain will fall along the eastern foothills late in the week.

(NRLMRY image)
--Typhoon Parma struck storm-weary Luzon Island late last week. Landfall was over the northeast, where wind damage was severe. However, I believe that highest rainfall has happened over the northwest of the island: Laoag City, Vigan and even as far south as the highland city of Baguio. Best that I can tell, based upon our database here at AccuWeather.com, rainfall has topped 80 cm at Laoag with nearly 70 cm pelting Vigan. Both Vigan and Baguio claimed 50-cm falls of rain during their respective wettest 24-hour spans.
-Trouble with Parma (as of 1800 UTC, Monday, a strong tropical storm roughly between Luzon and Taiwan) is that it is stuck in a region of light steering winds. Which means that it will spin for a few days off northern Luzon (or maybe southern Taiwan) unleashing even more extremely heavy rainfall. It was a typhoon last summer that unloaded about 2.5 meters of rain upon some highland site in Taiwan. Parma could potentially double the rain amounts already received over northwestern Luzon.

(JTWC image)
--Melor has been a dramatic super typhoon over the open Philippine Sea following its crossing of the Mariana Islands late last week. Anatahan, the whole island a volcano, took a direct hit from Melor.
-Melor will veer northward and northeastward east of the Ryukyu Islands (Okinawa among them) on Tuesday and Wednesday. It will then track over, or barely south of, the southern Japan mainland on late Wednesday to Thursday. Looks as though it will still be a typhoon, albeit a weakening one. This also looks like a potentially devastating storm wielding torrential, flooding rain and destructive wind. A cold front settling southward into the path of the typhoon will work to shunt its path eastwards while also greatly bolstering rainfall to its north.
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