AccuWeather.com

Mumbai Crosses 100-Inch Rain Threshold

Aug 30, 2010; 10:08 AM ET

EARLIEST FIRST 100 INCHES OF MONSOON RAINFALL?

Rains at Mumbai last week hiked rainfall in the city to more than 100 inches. Since the first of June, no less!

Rajesh alerted me last week that his city was having one of its wettest Monsoon seasons in its recorded history.

As of Aug. 29, our AccuWeather.com database has Mumbai-Santa Cruz Airport tallying 2,608 mm (103 inches) of rain since June 1. The actual number may be rather different owing to the method of encoding/decoding rainfall and that heavy rain was (and still is) pelting the city.

Further outbursts have heaped onto this tally another 15 cm or so.

For the Colaba site (actual site of record?), according to the IMD, rainfall as of Aug. 25 was 2,642 mm (104 inches), or 50 percent above normal (1,763 mm).

*Update*

I found the IMD page with up-to-date data. It shows, as of today, Aug. 30, that rainfall at Santa Cruz has reached 2,900 mm, or 114 inches, of which 138 mm fell within the last 24 hours.

As for Colaba, rainfall as of the same time has reached 2,783 mm (109.5 inches). New rainfall at Colaba is 69 mm.

These are all merely figures to someone nearly halfway around the world. I have to "wrap my mind" about the fact that this 2,900 mm--114 inches--has all happened since June 1. Three short months.

Here, in the green and moderately well-watered middle of Pennsylvania, it normally takes about three YEARS to collect 114 inches of rain.

And the wettest year ever registered in State College (1996) had 1,500 mm.

MUCH DIFFERENT STORY FOR MAHABALESHWAR

The crest of the Western Ghats, 1,000 or more meters above the sea, is the place to see the SW Monsoon in action.

The uphill climb of water-laden winds wrings out far more rain from the heavy Monsoon clouds than what happens on the west coast.

Mahabalaleshwar must be the spot to see the whole show unfold, being as how the town site lies along the crest of the Ghats about 1,380 meters above sea level.

IMD give normal rainfall to date (Aug. 30) to be 4,954 mm (195 inches) at Mahabalaleshwar. Rainfall, rather than being above normal, has been 3,514 mm for a shortfall of 1,440 mm, or 29 percent.

Why the contrast between well above normal and well below normal across the roughly 150 km between the two sites?

I do not know.

MORE RAIN ON THE WAY

I do know that numerical forecasts are showing more west coast rain (and locally elsewhere) with some heavy falls through at least the end of this week.

STATUS OF PAKISTAN FLOODING

The last three days have been nearly rain-free throughout Pakistan. That is good news for a flood-weary nation which still has a rain-swollen river stream right through its very heart.

However, the Indus River remains dangerously high along its lowermost reaches in Sindh.

At the last gauging site along the lower Indus at Kotri (near Hyderabad), the flow rate is lessening as of Monday.

According to the PMD, inflow at Kotri has slipped to 866 thousand cubic feet per second (cusecs). This is down from 950,000 cusecs as of Aug. 28, and from 965,000 cusecs near the time of highest flow on Aug. 27.

The PMD show that the two upstream gauges (Guddu and Sukkur), show high flow that is nearly stable as of Aug. 30. This is in the range of 550,000 to 575,000 cusecs--still a high rate of flow.

So, while its flood crest will pass out to sea and into history, the Indus River in Sindh will stay high for the next week and beyond.

WESTERN PACIFIC LIGHTS UP

Three named tropical cyclones are churning the western North Pacific Ocean where as recently as Saturday there were none.

Typhoon Kompasu is strongest of the three at this time, and it its aimed squarely for the islands of Okinawa.

A sweeping curve over the East China and Yellow seas is likely to lead to landfall on the western Korean Peninsula.

Tropical Storm Lionrock is located between Hong Kong and the island of Taiwan. This storm is forecast to hook northwest into southeastern China within about the next two days.

A third storm, wedged between the other two, has been dubbed Namtheun. It boggles my mind to believe that these three named storms can share as relatively small swath of ocean and hold storm (or typhoon) status for any substantial span of time.