General October Weather

[Manukau heads obs]

well there you go
i thought those showers might have hail in them

[mattyj46]

Mildest night here in Invercargill, around 10C, no wind, could be worse for the out of control fire down near Tiwai (around 15km from here).

[mattyj46]

Not really weather related but interesting never the less, have to say alot of people headed down for a look, was an impressive sight, the fireline I'd say is stretched at least 1km.

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A fire on Tiwai Spit in Southland is burning less than four kilometres away from Tiwai Aluminium Smelter.

The Fire Service says the fire is covering 50 hectares and is burning uncontrolled.

However, Southern Fire Communications Shift Manager Andrew Norris says the fire is not threatening Tiwai Point Smelter at this stage but they are working hard to contain the blaze. Four helicopters and 60 firefighters are battling blaze.

Norris says the blaze started shortly before 5pm on Friday.

Southern Rural Fire District spokeswoman Sue Peterson says the fire is quite a sight.

She says they are not expecting to have it under control until Saturday.

The fire is believed to have been started accidentally.

http://tvnz.co.nz/national-news/fire-ti ... nd-3091225

[jamie]

umm im some what confused as to what would cause this spike in wind speed. could it have been a bird sitting on it? im baffled unless there was a spike in the wind speed to go from 0 to 50 then to 0.. but i highly doubt that. anyone had anything like this before?

[tgsnoopy]

Most anemometers have a magnet rotating with the cups (or blades), this magnet operates a magnetic reed switch. I know from experience with other similar speed sensing reed switches that they can at certain speeds stop operating at all or suddenly give more than one count as the magnet passes.

It's unfortunate and tricky to resolve at times. Sometimes it can be as easy as moving the magnet a little closer, other times replacing the switch.

My point, this can and does happen.

If it becomes frequent you may need to investigate, replacement of a reed switch could be a fix, but it may also be a loose connection etc.

It becomes obvious when you graph the wind speed changing and see repetitive spikes at certain apparent wind speeds. Checking previous days will indicate if this was an isolate instance or maybe there is a problem.

Best selection of reed switches I've found is Farnell.

[Manukau heads obs]

what can cause a problem with the Davis anenometer is a ground loop problem, i.e elctrical interference
grounding the mast and making sure the AC power to the consol is well grounded can help

did the gust show on the console though?

[jamie]

cheers guys. i am not at my parents so cannot tell you if it is on the console as well. It is a wireless one so power should not have had an effect. It has been recorded as a high average wind speed of 273km/h.... BUT not as a gust. the gust record is still as it should be. Looks like an isolated incident as there is nothing like it in the last 5 days. Ill do some investigating later this week if i get down to my parents.

[DT-NZ]

Well, I can only best describe and sum up this October 2009 day in one word really.

Windy.

[DT-NZ]

Well, I can only best describe and sum up this October 2009 day in one word really.

Windy.

and, lots of it... wind... blustery, gusty...

[Manukau heads obs]

June and October are traditionaly the windiest months

[Michael]

Reckon October sun should end up around average given the next couple of days are to be sunny.

[mikestormchaser]

October has been a very cold month! brrr what we have had this month should of been in August.
Its been, windy very wet and very cold.