Moist week with possible thunder, 7-Apr to 13-Apr

jamie · Unread post by **jamie** » Mon 07/04/2014 12:58

It looks like a very moist week ahead. Some very decent numbers being thrown out of the models at the moment.

Will we get consequtive thunder days? There is no upper level wind so these convergent heat showers are likely to be quite pulsy.

NZstorm · Unread post by **NZstorm** » Mon 07/04/2014 19:41

Yes, weak shear but high moisture so thunderstorms will be pulse type with lots of rain locally.

BOP tomorrow,

Waitomo and possibly Auckland/Northland Wednesday?

Tornado Tim · Unread post by **Tornado Tim** » Tue 08/04/2014 09:26

Wow the GFS looks nice for this afternoon in central Waikato....Looks like the models have pulled in the moisture a bit more inland.
Karipro right bang in the middle, I'll keep an eye out this afternoon to see if its worth chasing but the forecast sounding is good, though weak in upper flow.

Just have to watch for the incoming moisture and when it starts coming over the Kaimais.
Metservice have it more coastal for potential Severe Storms, I bet they will change it later on this morning or afternoon if moisture starts coming in.

The unusually high SFC forecasted temps in Waikato will certainly help things kick off.

Jamie, you will be in a better position than me to chase in Karipiro, hopefully if things go off you can go there

Metservice T-storm Outlook:

Metservice wrote: A low near East Cape this morning is forecast to drift westwards across Bay of Plenty today. The combination of moist air, onshore winds and daytime heating over the land is expected to produce heavy showers, with a moderate risk of isolated thunderstorms in Bay of Plenty this afternoon and early evening. Any thunderstorms that do form are likely to be slow moving and as a result have the potential to be SEVERE and capable of producing localised downpours exceeding 25mm/hr. There is a lower risk of thunderstorms this afternoon and early evening in a surrounding area including inland parts of Bay of Plenty, much of Waikato and Coromandel Peninsula.

No thunderstorms expected elsewhere. However, rain with some heavy falls will affect eastern areas between Gisborne and the Kaikoura Ranges today (including parts of Wellington) - see latest Severe Weather Warning and Watch.

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Metservice Thunderstorm Watch

Metservice wrote:Issued by MetService at 08:34 am Tuesday 08 April 2014
Valid until 08:00 pm Tuesday 08 April 2014
This watch affects people in the following weather forecast districts:
Bay of Plenty
Rotorua

This is an alert to the potential development of severe thunderstorms with very heavy rain.

The combination of moist air, onshore winds and daytime heating over the land is expected to produce heavy showers and isolated thunderstorms in Bay of Plenty and Rotorua this afternoon until early evening. Any thunderstorms that do form are likely to be slow moving and as a result have the potential to be SEVERE and capable of producing localised downpours of 25-40mm/hr.

Rainfall of this intensity can cause flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips. Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.

Note: A Severe Thunderstorm Watch means conditions are favourable for severe thunderstorms in and close to the watch area. People in these areas should be on the lookout for threatening weather conditions and be alert for possible Severe Thunderstorm Warnings.

Issued by: Chris Noble

This watch will be updated by: 02:00 pm Tuesday 08 April 2014

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jamie · Unread post by **jamie** » Tue 08/04/2014 09:37

Funnily enough Tim, i am at an event tonight in Karipiro so ill be there for sure!

Tornado Tim · Unread post by **Tornado Tim** » Tue 08/04/2014 09:40

jamie wrote:Funnily enough Tim, i am at an event tonight in Karipiro so ill be there for sure!

Lucky Bugger, LOL

jamie · Unread post by **jamie** » Tue 08/04/2014 10:49

I'm at ngatea at the moment. Plenty of moisture flowing over the mountains. But cloudy as a result.

spwill · Unread post by **spwill** » Tue 08/04/2014 11:07

I will keep a watch next few days, if anything develops nearer Auckland I will chase.

Humid conditions here today, dewpoint 18C, current temp 23C, some high cloud, light winds.

treetop · Unread post by **treetop** » Tue 08/04/2014 12:40

showers/light rain starting to intensify BOP . Nothing spectacular yet. Tomorrow looks better for Waikato with hopefully less high cloud and more moisture.

David · Unread post by **David** » Tue 08/04/2014 13:52

Another warm day, with 19C dewpoints! Mostly cloudy with a few spits around at the moment. We reached 24.5C, just 0.6 short of my April record.

Tornado Tim · Unread post by **Tornado Tim** » Tue 08/04/2014 14:08

Thought this would happen, they reviewed and brought the risk in for more inland areas

Outlook:

Metservice wrote:Updated 1:50pm to include eastern and southern Waikato in moderate risk area.

A low has moved westwards across Bay of Plenty today, with winds turning onshore there. The combination of moist air, onshore winds and daytime heating has produced scattered showers throughout Bay of Plenty also inland parts of Waikato and Waitomo. These showers are expected to become heavier this afternoon, with a moderate risk of isolated thunderstorms developing in Bay of Plenty and eastern and southern parts of Waikato. Any storms that do form are likely to be slow moving and as a result have the potential to be SEVERE and capable of producing localised downpours exceeding 25mm/hr. There is a lower risk of thunderstorms this afternoon and early evening in a surrounding area as indicated on the chart.

No thunderstorms expected elsewhere. However, rain with some heavy falls will affect eastern areas between Gisborne and the Kaikoura Ranges today (including parts of Wellington) - see latest Severe Weather Warning and Watch.

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Watch:

Metservice wrote:Issued by MetService at 01:42 pm Tuesday 08 April 2014
Valid until 08:00 pm Tuesday 08 April 2014
This watch affects people in the following weather forecast districts:
Waikato
Bay of Plenty
Rotorua

This is an alert to the potential development of severe thunderstorms with very heavy rain.

The combination of moist air, onshore winds and daytime heating over the land is expected to produce heavy showers and isolated thunderstorms in Bay of Plenty, Rotorua and eastern and southern Waikato this afternoon until early evening. Any thunderstorms that do form are likely to be slow moving and as a result have the potential to be SEVERE and capable of producing localised downpours of 25-40mm/hr.

Rainfall of this intensity can cause flash flooding, especially about low-lying areas such as streams, rivers or narrow valleys, and may also lead to slips. Driving conditions will also be hazardous with surface flooding and poor visibility in heavy rain.

Note: A Severe Thunderstorm Watch means conditions are favourable for severe thunderstorms in and close to the watch area. People in these areas should be on the lookout for threatening weather conditions and be alert for possible Severe Thunderstorm Warnings.

Issued by: Chris Noble

This watch will be updated by: 08:00 pm Tuesday 08 April 2014

Tornado Tim · Unread post by **Tornado Tim** » Tue 08/04/2014 14:12

24-26 Degrees around inland Waikato under mostly cloudy conditions, quite amazing.....
Wouldn't be surprised if showers started popping up quite soon.

jamie · Unread post by **jamie** » Tue 08/04/2014 14:46

no sign of showers yet. Car showed 27 all the way from Ngatea to home. About to now head to Karipiro where hopefully ill catch some action.

treetop · Unread post by **treetop** » Tue 08/04/2014 16:21

Just stratiform cloud today, not a CB in sight, looks like a fizzer better luck tomorrow, dont waste your fuel this arvo !

spwill · Unread post by **spwill** » Tue 08/04/2014 16:47

Little in the way of sunshine/heating down there today.

A warm night on the way, currently 22C, dp 18C with medium level cloud cover moving in.

NZstorm · Unread post by **NZstorm** » Wed 09/04/2014 06:26

Some good low level convergence showing up on the gfs over inland North Island today. Today should see some cb development unlike yesterday.

Overnight min at Auckland airport was 19C with dp 17C.

treetop · Unread post by **treetop** » Wed 09/04/2014 06:52

The key trigger now will be for the low cloud to burn off. Is there any high cloud around today ? I am in the murk here, definitly killed it yesterday.

David · Unread post by **David** » Wed 09/04/2014 06:52

NZstorm wrote:Overnight min at Auckland airport was 19C with dp 17C.

Think you mean 18C min? Howick was 17C, more than warm enough

Manukau heads obs · Wed 09/04/2014 07:01

18c here this morning and almost mist in the air and low cloud

David · Unread post by **David** » Wed 09/04/2014 11:06

GFS shows good Lifted Index and CAPE numbers right up to Northland tomorrow, but Metservice outlook has no risk above North Waikato

NZstorm · Unread post by **NZstorm** » Wed 09/04/2014 11:17

David wrote:GFS shows good Lifted Index and CAPE numbers right up to Northland tomorrow, but Metservice outlook has no risk above North Waikato

Will be a fresher NE tomorrow which may make it harder to get good convergence. But the risk is not nil.

spwill · Unread post by **spwill** » Wed 09/04/2014 11:25

Any heating tomorrow will increase the chance of some west coast convergence, Auckland/Northland

Current weather here, cloudy, light winds, 22C, dewpoint a stuffy 18C.

Tornado Tim · Unread post by **Tornado Tim** » Wed 09/04/2014 13:17

Completely Overcast in Raglan, Light showers developing central Waikato according to the BOP Radar.

spwill · Unread post by **spwill** » Wed 09/04/2014 16:00

Sunshine cloud mix for Ak, towering Cu to the SE

jamie · Unread post by **jamie** » Wed 09/04/2014 16:09

Metservice cant make up their mind today. They had a thunder outlook for today thismorning which was very similar to last nights. Then during the day they canceled it saying there was not enough heating. Now they have thunder on the cards again.

spwill · Unread post by **spwill** » Wed 09/04/2014 16:22

Isolated thunderstorms have occurred

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