--A good deal has been written about the recent severe flooding -- and the outburst of rain the triggered it -- in the United Kingdom. The meteorology truly is remarkable and is worthy of a few words on this page.

The site of a record-smashing rainfall was the Lake District highland of Cumbria, northwestern England. It is the country`s wettest corner and the site of dramatic contrast in climate over short distances. And it is from here that the runoff of the highest-ever measured rainstorm flowed to inundate a swath of river bottom right to the Irish Sea.

Blogging from Scotland, Mark Vogan has summarized some details relating to the rainstorm and weather records. Many interesting statistics. And this link to the UK Met Office.

The record in question, highest measured 24-hour rainfall (for Great Britain/United Kingdom), was rewritten in the wake of a 314-mm (12.4-inch) cloudburst at Seathwaite, Cumbria. The old record was that of 279 mm (11 inches) of rain at Martinstown, Dorset, on July 18, 1955.

The record in question is not only an all-time, nationwide record, but it is one for the nation with (I believe, anyways) the longest running history of weather records, as United Kingdom weather records reach back nearly 300 years to 1727.

More about Seathwaite itself. While I am unsure as to the exact location in this swatch of rugged landscape, it lies in the heart of the high fells -- hills -- of the heavily glaciated (in Ice Age times) Lake District. I understand it to be within Borrowdale, a hollow reaching into the highlands from the north. Nearby Scafell Pike ranks as highest hill in England. Anyways, the site of the weather station gets an average of about 3552 mm/140 inches of rain (another source says 3,300 mm/130 inches) yearly. It is the wettest inhabited site of record in England.

The reference also gives that nearby Sprinkling Tarn (tarn being a small mountain lake) has an average yearly rainfall of over 5,000 mm (200 inches). How striking the contrast in rainfall with that of Penrith, a town right outside the Lake District. Here, average yearly of only 870 mm/34 inches much more befits the Midland than rainy western Britain.

To the extent that I am aware of the outburst (I was away from the office at the time) the trigger for the flooding rain was a stream of heavy rain tracking northeastward, trainlike. Elements of heavy rain were driven, one after the other, off the Irish Sea and into both Cumbria and neighboring Dumfries and Galloway, Scotland. An uplift of the rain-bearing clouds into the highlands greatly bolstered rainfall. Then, too, a share of tropical moisture linked ultimately to Hurricane Ida could have "fattened" the rain output.

The rivers that flooded most severely, the Derwent and tributary Cocker, drain north from the Lake District including Borrowdale, site of the record fall of rain. These rivers transferred the overwhelming runoff into the towns of Cockermouth and Workington.

Image credit: NRLMRY

-Elsewhere, one thing that catches my eye is a gathering tropical depression south of Vietnam and east of the Malay Peninsula. This needs to be watched as a potential flood-maker for southern Thailand (Isthmus of Kra) in about five days.

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--October ended with a serious dearth of rain over southern India, most of all over that part normally watered by the North East Monsoon. Take Chennai, where the lack of the usual October cloudbursts left rainfall at only 16 percent of normal, or a skimpy 1.7 inches. Virtually all of that 1.7 inches fell during the last week of October; it proved to be a harbinger of things to come.

Things to come, indeed. Rains burst forth in a big way at the middle of last week along the southern east coast of India. Most hit Tamil Nadu, but a little did reach into southern Andhra Pradesh. The area was hit with heavy falls of rain daily through the end of the week, even into Monday. At Chennai, daily rainfall of 6-12 cm brought the monthly tally to about 45 cm as of Monday. For perspective, normal rainfall for all of October would be 25 cm, and for November, 30 cm. So Chennai has more than caught up with the normal seasonal (starting Oct. 1) rainfall to date.

Also seeing a big uptick in seasonal rainfall were a number of cities from southern Andhra to southern Tamilnad. Nellore, Karaikal and Cuddolore all had 25-40 cm (at least) within five to six days as of Monday. I have to believe that some falls have reached 50 cm or more during this stretch.

-The trigger for the big outburst of rain was a tropical weather system that may have been linked to the last Pacific typhoon, Mirinae, which broke up over eastern Indochina at the start of the month. I speculate that, following Mirinae's breakup, a low pressure wave hitched to high pressure and outflowing winds aloft made its way slowly westward over the southern Bay of Bengal to southern India and Sri Lanka. This would help to explain the rainy outbursts.

As of Monday, there have been some unusual November downpours on the west coast north to Karnataka, Goa and southern Maharashtra. Stray thunderstorms reached the northern Deccan, also in Maharashtra. These downpours strike me as further confirmation of a `ghost of Mirinae` theory.

-Now, as of Monday, tropical low pressure is organizing west of India. Satellite imagery...

...would have me believe these words to be understated--that this might be a tropical depression as of the time of this IMD (India Meteorological Department) satellite shot.

Anyways, this low is drifting to the west-northwest as I write. Numerical forecasts (ECMWF and GFS) would have this low veer towards the north and the northeast leading to a landfall upon the northern west coast of India two or three days hence. Could Mumbai see a rare November cyclone? The odds for this are measurable.

Cyclone or no cyclone, the atmospheric setting is a rather tropical one with southerly wind flow dominating the Subcontinent. This will lead to a late-season outbreak of showers and thunderstorms as far north as the Himalaya. Admittedly, coverage of rain will be spotty, but there will be some abnormal downpours from the northern Deccan right north to the Foothills.

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--Sorry, everyone, for my absence from this column. I have been otherwise occupied. I see I have missed out on a lot of comments. Some of them a bit wild. I would hope that it would not be personal.

--Questioners have asked as to the North East Monsoon--or lack thereof. October should be the time of rising pressure over the Subcontinent, more so to the north, the outcome being a reversal of winds over peninsular India. During and following this reversal, there comes a time of heightened rainfall over southeastern India to eastern Sri Lanka; it usually lasts well into December.

For whatever reason (I cannot cite any fundamental cause, only symptomatic signs) the NE Monsoon has been weak with little rainfall. As of Oct. 26, rainfall at Chennai was a mere fraction of a millimeter, whereas more than 20 cm should have already fallen, based upon historical data. A full month of rainfall would be about 27 cm.

Moreover, it has been a hot month--more than 2 degrees C above normal so far. Most of the Subcontinent has been warmer than normal, too--more so towards the northwest.

Whatever the underlying cause for the dearth of rain driven by the NE Monsoon, it would seem that meaningful rain lies "right around the corner" with rainy outbreaks as early as Tuesday. I see that the GFS numerical forecast is showing a fairly steady northeasterly surface wind over the Bay of Bengal--a hopeful sign in and of itself.

Anyways, the GFS "QPF" (quantitative precipitation forecast) shows meaningful rain on most days through at least the first of next week. Also, some kind of cyclonic whirl is forecast to ripple westward along the Inter Tropical Convergence to Tamil Nadu and Sri Lanka. This would tend to dry the coast ahead of it then bring some heavy falls of rain upon reaching land--were it to happen.

--Lupit, the former Super Typhoon, has nearly transformed into an extra-tropical storm in skirting southeastern Japan on Monday. Lupit will end up over far-northeastern Asia--maybe Chukotka--late in the week.

The soaking, windswept rain that pelted Greater Tokyo was anything but tropical in feel as the temperature slipped below the 15-degree mark late in the day. Lupit had simply strayed out of its natural environment and, rather than dissipating, began taking advantage of the north-south thermal gradient that normally powers mid-latitude (extra-tropical) storms.

--Another tropical storm has taken shape. And it is one that bears watching for the Philippines. Tropical Storm 23W will soon be sweeping through the southern Mariana Islands (Guam, Saipan). From there, it looks to be a westerly path over the open Philippine Sea with typhoon status at midweek. This storm could reach the Philippines from the east at the weekend.

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--Parma is nearing its end. As of 1200 UTC on Monday, Oct 10, this tropical storm was swirling over Hainan Dao aimed for the Gulf of Tonkin and eventual last landfall, this time upon northern Vietnam. Parma will leave behind a dramatic legacy, mostly out of northern Philippines, which bore the brunt of three landfalls.

Parma began as a tropical storm during the last days of September. As it spun away from Yap Islands, Parma wrapped into a super typhoon with winds of Category 4 intensity by the start of October. Shortly thereafter, Typhoon Parma still packed a devastating punch as its eye crossed northeastern Luzon Island.

Had Parma simply kept on tracking toward the north and west, it would have been yet another strong, destructive storm to strike the most cyclone-prone nation on Earth. There were the usual flooding rains along with destructive winds. However, thanks to interaction with the even mightier Typhoon Melor, which was working its way towards Japan, a much weakened, downgraded Parma stalled and then backed southeastward, landing once again in northern Luzon. Flooding rains, though not severe winds, returned to the area.

Parma actually slipped off northeastern Luzon long enough to claim a third landfall at about the middle of last week. Then, at last, Parma drifted westward to the South China Sea and away from Luzon on Friday.

In its wake it left more than two meters of rain (about 87 inches, by my best reckoning) over the highland city of Baguio. Half of this fell within about 30 hours ended on Friday, local time. Near to west shore of Luzon, Parma also left about one meter of rain at Vigan with nearly as much striking nearby Laoag City. And Parma dealt out half a meter of rain in Dagupan.

The above are merely climatological statistics; cold hard numbers. But the cloudbursts of rain that they bespeak unleashed devastating floods and suffering for many, many people.

--Things have really quietened over the Subcontinent now that the abortive tropical cyclone has long since died out. A segment of the Westerlies has taken hold far to the north and has flushed the northwestern half of the Subcontinent with dry air. The IMD have adjusted the line of Monsoon withdrawal well southward, albeit still short of the average alignment for the time of year.

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Image credit: Navy Research Lab Monterey -- NRLMRY

--Typhoon Melor in making its last dash for southern Japan. Latest word from the JTWC has Melor ranked as a Category 1 storm; however, the JMA still have Category 2 status for the typhoon.

It is clear to me that transformation from true tropical to extra tropical in nature on the part of Melor has begun based upon the asymmetry of its cloud shield. Moreover, surface air temperature and dew point over southern Japan is too low to qualify as tropical.

At the time of the above satellite shot (Wednesday night, local time), the storm center was plotted directly south of the Kii Peninsula on southernmost Honshu Island. Latest JTWC and JMA movement was northeastward at 25 knots/45 kph. Meaning that landfall over southern Honshu will happen within a few hours after this posting.

The relative coolness of air over Japan suggests to me than Melor will track somewhat to the right of that indicated by the aforesaid agencies, but I believe more likely north and west of Tokyo. The answer will be known within several hours, one way or another.

This storm is going to pour 10-20 cm of rain over much of Japan, the far southwest and far north being the primary exceptions. Amounts above 30 cm, maybe even 50 cm, will happen in southern Honshu. The area of Owase on the southeast-facing Kii Peninsula is ideally located for extreme falls of rain in storms like Melor.

Melor will sweep out to sea east of northern Honshu as a tropical storm during Thursday afternoon and evening, local time.

--Tropical Storm Parma has become stuck, all-but dead in the water in and about northern Luzon Island, Philippines. The latest plot of Parma's center had it a bit east of Iligan Point. Weak steering winds that have virtually becalmed Parma will keep it parked in the area of northern Luzon for another day or two.

The latest on Parma has it a minimal tropical storm with 35-knot/65-kph highest sustained winds. Owing to proximity to rugged northern Luzon, Parma is bound to weaken further and lose, at least temporarily, tropical storm status.

-Whether storm or depression, Parma will pose further serious flood threat to northern Luzon, the northwest most of all. This area has seen widespread 30-90 cm falls of rain owing to Parma. At Baguio, 36-hour rainfall ended Wednesday evening, local time, was near 40 cm. Thus, Parma's output in the highland city has reached one meter, or 40 inches.

-Numerical forecast models still show Parma leaving to the west of northern Luzon late in the week. Its forecast track over the open South China Sea could see a return to tropical storm status ahead of a landfall upon south China.

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