These Canterbury Floods are moving in to Otago.
Here is a wider view. This will definitely continue through a fair bit of the night. Question is now how long will it continue tomorrow? The forecast models showed the plume you see coming in from the right sort of petering out and disengaging and tracking north.
A wider view.
These images show where the most recent global models thought it would be at the moment (6pm today). In order ECMWF, GFS, Access-G and CMC.

According to the models the rain band should start moving back to the north again about now, but this time with much less rain. ImageImageImageImage
Here are two versions of the next 48 hours. This is the latest GFS Version.
And the latest GFS version.... basically identical.

Bear in mind that each frame is 6 hours apart and in many ways the most important point in this drama is right now as the source of moisture begins to pull away to the East.
A close look at the satellite images suggests this storm has stopped tracking south and has been stationary from 3.40pm to 5.40pm NZT.

If the predictions are correct - as it seems they are - it should start moving northwards fairly soon. Back into @grenow territory, Waipara.
And the good news is that as this happens this should also happen. I.E. it should get both weaker and accelerate as it moves north. I.E. in theory the vast bulk of the heavy rain has already fallen.
This animation begins with rain over the last 6 hours (1st frame - forecast not actual) then what is forecast the next 48 hours.
I.E. if you subtract what you see in this first picture from the 2nd. that will give you a rough estimate of what remains. In the red areas that is about 30-40mm & maybe 30mm more in the dark patch.

Also Note: This is not a forecast & I am not a meteorologist. ImageImage

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More from @althecat

1 Jun
Well its hard to know where to begin with today's #MiddleEast and #HornOfAfrica rainfall forecasts.

The action is now further north, and west. Here we see the consequences of the first phase of what appears to be becoming a continuous #WesternSaharaPlume. Image
An bit of a battle us underway between a high pressure system over Northern Erope and the plume which is entering at the bottom left in this image of Jetstream level 250Hpa 11km high winds. Image
While the model forecasts remain optimistic that an orderly jetstream may eventually appear, so far this has not happened. And in the meantime these winds are picking up moisture in the tropics and taking it in large quantities to places where its not expected.
Read 26 tweets
30 May
A big day for #WestAfricaMonsoon observation.

A full plume event is becoming obvious in central & eastern Europe + Russia. We also have thunderstorms over the Red Sea, and a low circulation heading towards a collision with water vapour over Israel.

Today's forecasts follow.
Visually speaking this is the most extraordinary looking satellite observation of the day.

Now into its sixth day the #EastAfricaWaterPlume has been generating lots of rain over the Red Sea, both last night and today, & right now just off the coast of Jeddah. @Arab_Storms
Here we see a wider view while it is not that obvious in this view, the stream of water vapour heading up the Western Sahara coast is running fast and hot. Later I will post an initial post tracking its impact in Europe. But for now its worth looking closer at North Africa.
Read 27 tweets
30 May
Upstream flow gauges in Temuka, Rangitata, Rakaia & Waimakariri appear to be peaking or in the case of the Waimakariri close to peaking.

Meanwhile the official ECAN alerts page seems to not be freaking out, so that's all good >> ecan.govt.nz/home/flood-war….

Steady as she flows. ImageImageImageImage
"Breakouts" in the Ashburton vicinity & inland, are the major concern at present. But whatever "breakouts" are they sound a lot less alarming than floods and evacuations.

Also no alarm around the major rivers, yet. Also good.

Alerts here >> ecan.govt.nz/home/flood-war… Image
The remaining concern will be river mouth flood/tide collisions. High tide timing today is around 6.30am near Timaru, 7.50am at the Rakaia and around 8.30am in Christchuch and at the Waimakariri river mouth. ImageImageImage
Read 6 tweets
29 May
It appears this pretty looking storm is doing some serious damage. Stay safe Ōtautahi. Image
And we have a live report from north Canterbury.
NOTE: This is not an official forecast. But it is alarming. It seems that that peculiar cloud formation is special in a number of rather alarming ways. [Image: @NOAA's GFS model forecast, latest run.]
Read 13 tweets
25 May
With Cyclone #Yaas soaking up all the moisture east of the #MiddleEast and #HornOfAfrica it was a relatively calm day. Albeit not without another intense set of storms along the Red Sea Coast in the Jinzan mountains.

Today's rainfall forecasts follow.
The days began relatively quiet on the #WestAfricanMonsoon front thanks to Cyclone #Yaas. This image shows a strip from the Libyan Coast across the Sahara down to the Congo.
And it remained fairly quiet over the great forests of equatorial Africa today. But further West over the Ivory Coast and the West Sahara the #WestAfricaWaterPlume continued to pump water vapour across the Sahara into Europe.
Read 16 tweets
25 May
Here is the continuation of the #WestAfricaWaterPlume transformation of European weather this morning into something which is both unpredictable and not particularly nice, i.e. windy wet and cold.
The following three animations are offered to help Europeans who are curious to understand what is going on. Our weather reports tend to be geographically confined in a manner that obscures the bigger picture.
The first shows the water vapour picture over 84 hours till Friday arpund midday. The #WestAfricaWaterPlume can be seen coming in bottom left over Algeria. simultaneously another storm is coming in at speed into the British isles. Hence all the rain.
Read 6 tweets

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