General May Weather

[David]

Not often you’d ever see Christchurch the hottest and coldest location in New Zealand at the same time!D68A6CA2-2BDB-48C3-AE6C-FF32E1F3166D.jpeg

Haha just came to post about this too. Now showing an even bigger difference, 2.3C vs 18.7C!

[Richard]

Not often you’d ever see Christchurch the hottest and coldest location in New Zealand at the same time!D68A6CA2-2BDB-48C3-AE6C-FF32E1F3166D.jpeg

Yes that is so interesting where the air is trapped under the warm wind. Unlike Friday night here the wind kept up with the odd gust

[tornado]

it still storming over fordland

[tornado]

]reports of a funnel cloud in rotorua

[NZstorm]

it still storming over fordland

Typical down there though. There will be intermittent lightning activity all week for the west of the SI.

Closer to Auckland, Tuesday and Friday look to be the days with medium thunder potential. Perhaps slight potential tomorrow with a warm front.

[tornado]

this upcoming week i am excited. there is some potential for auckland this coming week. winters waking uo now though

[cbm]

Crazy. Got a layer of dense fog up to 250m elevation today which is massively deep. With a really sharply defined ceiling. It's still 100m or less visibility in rural areas now, at 2:30pm. Yet the urban areas have managed to core punch through it, I have sunshine on my home cams now and see the same on the Hamilton traffic cameras. Even more confusing the temp drops 1C as you exit into the clear skies above. So not an inversion layer as such. Seems like have a much drier airmass layered on top.

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[Cyclone Tracy]

Crazy. Got a layer of dense fog up to 250m elevation today which is massively deep. With a really sharply defined ceiling. It's still 100m or less visibility in rural areas now, at 2:30pm. Yet the urban areas have managed to core punch through it, I have sunshine on my home cams now and see the same on the Hamilton traffic cameras. Even more confusing the temp drops 1C as you exit into the clear skies above. So not an inversion layer as such. Seems like have a much drier airmass layered on top.

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Just theorising and my 2 cents worth...… given the fog has continued so late into the day, the surface cooling overnight combining with the light moist easterly has created a localised advection fog scenario. The urban areas have heated during the day.

[tornado]

good risk for thunderstorms in auckland on tuesday and slight risk tommorow cant wait to hear more thunder as we only uad one thunderstorm day this year.

[NZstorm]

A number of airports from Kaitaia to Ashburton got to 20-21C today. But Hamilton airports high was only 11C due to fog.

Both Manapouri and Milford Sound airports reported thunder.

[cbm]

Crazy. Got a layer of dense fog up to 250m elevation today which is massively deep. With a really sharply defined ceiling. It's still 100m or less visibility in rural areas now, at 2:30pm. Yet the urban areas have managed to core punch through it, I have sunshine on my home cams now and see the same on the Hamilton traffic cameras. Even more confusing the temp drops 1C as you exit into the clear skies above. So not an inversion layer as such. Seems like have a much drier airmass layered on top.

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Just theorising and my 2 cents worth...… given the fog has continued so late into the day, the surface cooling overnight combining with the light moist easterly has created a localised advection fog scenario. The urban areas have heated during the day.

That seems possible. For the breeze to come in though it would have to via the Firth of Thames. Everywhere else is walled off by ranges. I confirmed that finding when drove back down from that Carpark on Mt Pirongia, the car thermometer went from 10C to 12C after dropped back down into the dense fog, given it was parked in the sun up there a false reading would do the opposite. Crazy how even a small urban area can put out enough heat to modify the local cloud cover.

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[talbotmj15]

Question people. Does Twizel average a single snow event yearly? Apart from the obvious altitude difference between Tekapo 700msl and Twizel 480msl, Are there any other factors that anyone is aware of that is behind the huge difference in snow amounts annually for Twizel? Just wondering as to why Twizel seems to get so little in terms of snowfalls compared to Tekapo. Also what are the ideal conditions for Twizel to get snow in terms of weather modeling?? Any info much appreciated.

[snowstormwatcher]

Question people. Does Twizel average a single snow event yearly? Apart from the obvious altitude difference between Tekapo 700msl and Twizel 480msl, Are there any other factors that anyone is aware of that is behind the huge difference in snow amounts annually for Twizel? Just wondering as to why Twizel seems to get so little in terms of snowfalls compared to Tekapo. Also what are the ideal conditions for Twizel to get snow in terms of weather modeling?? Any info much appreciated.

Twizel is more sheltered than Tekapo. In my experience most of the heavy rain/Snow events that effect the Mackenzie area tend to come from the East or Southeast and are normally warm advective and often snow will only fall as low as 500-600m. Also positioning of low pressure systems tends to mean areas further North seem to get far more rain/snow, There are many low level snow events that simply bypass South Canterbury and only effect areas north of the Rangitata.

[Orion]

Interesting and beautiful red reflections of sunrise on clouds here just at the moment.

[Chris W]

Beautiful NW arch and a moderate wind in Amberley, nice and warm for late May.

[spwill]

The end of the long dry pattern for Auckland now, a lot of unstable weather/heavy showers heading our way next 10 days.

The Ski fields will start picking up snow from later in the week.

[midgrove]

Crazy. Got a layer of dense fog up to 250m elevation today which is massively deep. With a really sharply defined ceiling. It's still 100m or less visibility in rural areas now, at 2:30pm. Yet the urban areas have managed to core punch through it, I have sunshine on my home cams now and see the same on the Hamilton traffic cameras. Even more confusing the temp drops 1C as you exit into the clear skies above. So not an inversion layer as such. Seems like have a much drier airmass layered on top.

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That could be what is known as "wet bulb effect" when the temperature sensor has moisture and encounters dry air, the moisture evaporating from the sensors cools it briefly. When I was doing upper air flights we often saw this effect when the radiosonde went from a moist layer to dry air

[cbm]

Crazy. Got a layer of dense fog up to 250m elevation today which is massively deep. With a really sharply defined ceiling. It's still 100m or less visibility in rural areas now, at 2:30pm. Yet the urban areas have managed to core punch through it, I have sunshine on my home cams now and see the same on the Hamilton traffic cameras. Even more confusing the temp drops 1C as you exit into the clear skies above. So not an inversion layer as such. Seems like have a much drier airmass layered on top.

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That could be what is known as "wet bulb effect" when the temperature sensor has moisture and encounters dry air, the moisture evaporating from the sensors cools it briefly. When I was doing upper air flights we often saw this effect when the radiosonde went from a moist layer to dry air

Sure that effect does occur at times. However as I said in a later post I saw the difference again when drove back down into the dense fog, the temperature went up by 2 degrees. Normally with a car parked in sun and some heat from the engine you see the car thermo over read when first start, then drop as get some airflow on the sensor. The fact I saw the opposite suggests it was a real temperature difference.

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[NZstorm]

A cold front will be moving into the west of the North Island Thursday evening with some thunderstorm potential. Looks like the 500mb -19C will make it to western areas which will be cold enough for lightning given the moisture. If Auckland gets a storm from this front it will be early Friday.

[mattyj46]

https://www.odt.co.nz/news/dunedin/autu ... est-record

[NZstorm]

Thunderstorms starting to line up out in the Tasman! Taranaki looks high risk this evening with isolated severe rain/hail/wind/tornado. Lightning probabilities spreading north with the front overnight.

Cold system really starts moving into the North Island later tomorrow. Will keep a watch out for thunderstorms lining up Friday evening with a front. Will depend on moisture though.

[Orion]

Strong winds and north-west rain through the night, various thumps and bangs audible, hope no damage done as the wind sounded worse than I've heard for some time.

[tornado]

taranaki could have a possible tornado as thunderstorms move in their region tonight. taranaki is new zealands tornado alley. auckland tommorow could see thunderstorms as well. possible hail on saturday according to weatherwatch.nz winter is waking up. warm going away. cold coming in

[Thunder081]

Got sea sprays and whirlwinds on Wellington's harbour

[Razor]

Output from the Severe Warned TS around Hokitika last night about 8pm. From the West Coast Civil Defence facebook page