Stormy weather - Prapiroon - due for 3-5 August

It looks possible that an area of low pressure east of the Philippines will head to S China Sea and intensify into a tropical storm/typhoon. HK Observatory forcast for Sat 5th and Sun 6th Aug is: "CLOUDY TO OVERCAST WITH OCCASIONAL HEAVY RAIN AND SQUALLS." European Centre for Medium-Range Weather Forecasts (ECMWF) seems to reckon a typhoon possible; tho perhaps it will pass westwards to the south of HK. Image from a forecast for Saturday (evening HK time); too early to be sure this will be correct of course, but worth watching situation develop.

Post edited by: Martin, at: 2006/08/01 09:34

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Prapiroon now named, in South China Sea, and on the move and intensifying.

Forecasts not yet in great agreement, but perhaps likely to head towards Hainan, passing to the south of Hong Kong; Hong Kong Observatory forecasting "EAST TO SOUTHEAST FORCE 5, OCCASIONALLY FORCE 6 OFFSHORE." for Friday, as well as similar for Thursday, with winds strengthening late tomorrow (Wed), and winds weaker but still showers for the weekend.

ECMWF, by contrast, has storm coming v close to Hong Kong during Friday.

Watched the lightening strikes last night, associated with outer rain bands of typ. Wind picking up ever so slowly. Seas in messy state of Sai Kung, but reckon things might change in next couple of days. Good chance for some ocean mixing for HK waters as the thermocline has been very pronounced (24C at 25 m, 27C on surface).
Thats the news from E Hong Kong...

HK Obs radar showed a small flurry of rather wicked looking rainstorms pass westwards over area just north of HK yesterday evening. Now - earlier than HK Obs had forecast yesterday - rain from Prapiroon starting to affect Hong Kong. Winds picking up, albeit Number 3 signal still some time away (hours?) Still variations in forecast tracks, but landfall over or a little east of Hainan looking most likely - as in current compilation of forecasts from MIT

Easterlies from Prapiroon sending fair waves to Cheung Chau's east beach (Tung Wan). This taken at around 2pm - shortly before period of rain. IMAGE(<a href="">

Prapiroon now a typhoon; and (from around 4.20pm) Number 3 signal hoisted. Still seems headed towards Hainan/western Guangdong, but seems to have intensified faster, moved nearer Hong Kong today, than some forecasts - inc HK Observatory - predicted. Looks to be rather indistinct eye in latest satellite images.

Cheung Chau's main waterfront - on west of the island - sheltered from the easterlies, but rainy this aft; albeit rain not bothering everyone. IMAGE(<a href="">

also cc; the lights of the island's police car seem bright on dark aft: IMAGE(<a href="">

rainwater drops from cafe shelter, and umbrellas: IMAGE(<a href="">

Radio reporting on tree falling on road to Sai Kung; here on Cheung Chau, looks like there's an umbrella shortage... IMAGE(<a href="">

Up early, finding powerful winds blowing over Cheung Chau (my place sheltered just now, happily); gusts ripping across surface of sea below. Checking realtime weather info for Cheung Chau on HK Observatory site, wind speed at CC has been continually increasing, but jump in last hour or so to around 85-95km/h, which is gale force 9, almost 10 Iyes folks, if signals applied to Cheung Chau, and not Victoria Harbour, the Number 8 would be up now, and HK would about grind to a halt; as it is, I guess ferries from CC could be halted). 

- quick look at other weather stations that maybe exposed, and seems CC has strongest winds just now, beating even Waglan [which recording small jump in wind speed as I write this, to 80-85km; cc winds up a little too]. Via Obs main page, Prapiroon was lately around 310km ssw of Hong Kong, and still on track towards Hainan/w Guangdong (other forecasts agreeing with this track, so no surprise shifts in last few hours [tho to my eyes, satellite animation seems to show eye collapsing, then system reforming with jump towards north; 10-minute average winds recorded Cheung Chau now to over 100km/h; note that 118km/h sustained wind is hurricane force, so winds here indeed strong]).  [it's now 6.44am]

Post edited by: Martin, at: 2006/08/02 22:44

Went out this morning, to have a look on Cheung Chau as Prapiroon passes by.

First thing - a tree down near my place

Went out this morning, to have a look on Cheung Chau as Prapiroon passes by. First thing - a tree down near my place IMAGE(<a href="">

to Tung Wan - normally placid, as Cheung Chau is sheltered by various islands; today relatively large waves. Just after taking this, had message from Charlie Frew: gusts on Cheung Chau to 130 km/hr. Certainly powerful gusts as I took this. IMAGE(<a href="">

Along south coast, waves larger, and gusts ripping spray from the sea. IMAGE(<a href="">

Also s coast Cheung Chau; while I was taking shots here, my umbrella got blown or washed away - just vanisthed. IMAGE(<a href="">

Meanwhile, back on the main Praya - in lee of main winds - some folk drinking coffee, others working, or heading to ferries IMAGE(<a href="">

east-west running street acting like a wind tunnel; brolly carriers beware IMAGE(<a href="">

Tho "only" Number 3 signal up, winds recorded at Cheung Chau have been storm force - 10-minute average in range 85-105 km/hr - for much of this morning. - while chart for Ngong Ping shows sustained winds of over hurricane force (ie over 118 km/hr - actually reaching over 130 km/hr for 10-min average); Charlie Frew has emailed re gusts there reaching 176 km/hr IMAGE(<a href="">

Post edited by: Martin, at: 2006/08/03 12:39

During the afternoon, HK Obs radar showed rain bands towards centre of Prapiroon were close to western HK. Here, not too much rain CC waterfront, but dark beyond the typhoon shelter - the heavy rain indeed closing in. Rather dark at the time, as clouds thickening overhead. IMAGE(<a href="">

And a little before 5pm, heavy rain indeed falling, with great gusts sweeping across rooftops, through streets, and sending spray scudding across the typhoon shelter (which indeed relatively sheltered from predominantly easterly winds). IMAGE(<a href="">

Not too many people roaming the Praya at this time!

[img width=600]

fishing boats huddled together in the typhoon shelter, as squalls blast across Cheung Chau IMAGE(<a href="">

Back on Internet, on HK Observatory site: 10-minute average winds at Cheung Chau peaked at 115 km/hr at 5pm - just short of hurricane force. While at Ngong Ping, 10-min average winds rose to around 170 km/hr, and then no more weather data: gotta suspect the equipment got wrecked by the winds (here, at least Category 2 on hurricane scale, tho this for 1-min average I think).

Post edited by: Martin, at: 2006/08/03 18:48

Ngong Ping station went dark around 4:30pm this afternoon. Gusts were registering over 200 km/h for about the hour before that.

Downed trees, broken limbs, and the like here on Peng Chau. One of the trees fell on a house.

Thankfully the wind changed directions around 5:30pm from the East to SouthEast, so Peng Chau's Tung Wan will be quieter tonight.

South China Morning Post is among media with questions re whether HK Observatory was correct to only issue Number 3 signal yesterday, when west of Hong Kong experiencing storm and even hurricane force winds, and there were gales blowing in the harbour. Does seem a grave error, apparently making a mockery of the signals. (It may not have been crucial to close down the city, but there were dangerous winds. Perhaps the outmoded signalling system is at least partly to blame; also HK Observatory being rather stick in the mud, or even erring on side of caution with regard to effect on business.

In email re this, Roger Kendrick suggests "Surely with the level of technology now available it is easier to be more specific with regard to warnings." Much discussion of this on Weather Underground forum; one post making a point I'd noticed: bulletin(s) from HKO mentioned winds at, say, Waglan - but not Cheung Chau, where winds far more powerful; was this partly to cloud the issue, make it seem more reasonable to not issue Number 8?

I earlier (2004) had email discussion with KY Yeung of HK Observatory, regarding my impression that Number 8 signal is not great: are times when it is issued and looks like could be far worse than gales to come, other times when gales are all that appear likely: in first case, closing down Hong Kong seems wise, while shutting much of the city for gales not so wise. I'd suggested having two different signals for these situations (tho Number 9 - increasing gale or storm signal - could play stronger role here). Yesterday was perhaps one of the more borderline cases: the eye was virtually certainly missing Hong Kong, by fair distance; yet there were gales and even stronger winds. No need, then, to close all Hong Kong, yet should have warned of dangers, and regional variations. People living on Cheung Chau, say, maybe should not have had to take ferries to jobs in the city. Hong">]Hong Kong Number 8 tropical cyclone warning needs revamping?