Summer for travellers

The early golden weather has come exactly on time and in accordance with predictions that were made in our almanac 2012 and in our online articles.

Between now and around about this time in January, Auckland and the top half of the North Island can expect less than a handful of serious rain days.

The hottest temperatures of the season may also occur in this time frame.

It means summer season has effectively arrived, as expected due to the moon method of longrange forecasting.

Travellers are beginning to consider where to book their trips away over the season. In NZ, Hawkes Bay is the most affected dry region this time, receiving little or no rain until 20 January with the exception of one day around 1 December.

For them it may be a difficult summer, with substantial rain relief not until February, then April.

In December, from 4th-22nd is mainly fine for the North Island, followed by the interval 4-18 January.

The next extended completely dry interval for Auckland is over the last week of February.

In Wellington and lower North Island only 3 or 4 rain days are expected for December, then the region is mainly dry for the last 10 days in January and the second half of February.

In Christchurch the second half of January and both the first week and the second half of February are settled, and in Dunedin the second half of December is mostly looking good, also the last 10 days of February.

The far South looks set to enjoy the last 10 days of January and the first and last weeks of February, and some districts may receive less than 6 rain days between mid January and mid March

There are, of course reasons why summer is this side of the season this year, which was the reverse of the situation when summer was a washout for many in 2009-10.

The engine of summer is the way the perigee and apogee (distance of moon from the earth), combines with the dates of full or new moons.

When these are closer in summer months the season tends to be drier, and when perigee alone is closer we get warmer summers.

For those planning to visit Australia over coming months, one might avoid Brisbane in the last days of November, and give Melbourne a miss around 9-10 December.

About 11-13 December rain affects the whole Queensland southeastern coastline.

A tropical low begins to build in the Coral Sea about the 9 December and slowly works its way south, affecting Queensland's North, South and Sunshine Coasts, especially around 13-14 December.

From the 17 December on, this system drifts east and then south, with parts of it extending across to Tonga and adversely affecting all islands between, reaching NZ around the 21st to deliver a pre-Xmas two-day dent to the North Island's long spell of fine summery weather.

After these unsettled pre-Xmas showers, inclement weather for NZ does not return until the end of December, at the same time as Melbourne receives rain from a low and associated cold front that comes through the Bight.

Around 7-8 January dark clouds in the form of a tropical low threatens Brisbane, but will likely be a false alarm, as it gets carried south by the south-trekking moon to threaten the top half of NZ about the mid month.

Meanwhile a tropical cyclone builds in the NW of Australia and drifts down the west coast during January’s third week, bringing rain there and also to most of coastal Queensland and NSW.

In the last days of January a severe storm affects Melbourne and a tropical cyclone forms in the Coral Sea, bringing a swathe of destruction across the Pacific.

No cyclones are expected around Australia during February

In the Pacific islands, the current tropical depression will move further south and dissipate by 24 November, whilst a convergence zone forms from the Solomon Islands to Futuna around 25 November, which should become a fairly intensive and widespread low pressure system about Nuie and Southern Cooks around 26 November.

At the same time a tropical cyclone brews off Brisbane which should proceed south, reaching the south west coast of NZ around 5 December, just as a large low pressure system forms and builds between the Solomon Islands and Vanuatu 4-6 December.

From then to 9 December a low extends from Vanuatu to the Solomons and then builds in strength to become seriously menacing around 15 December, centered on Fiji and likely to bring thunderstorms, destructive kingtides and strong winds, enough to warrant the battening down of hatches.

It is also a possible earthquake risk time in the Pacific seismic zone.

As this system declines it splits into two separate systems around 17 December, centered around both New Caledonia and Kermadecs.

The next destructive system for the Pacific is around the end of January

Travellers to the US may wish to avoid the floods that are expected between 25-29 November in Arkansas, Mississippi, and Ohio, and a possible storm around Florida in the last days of November associated with the near or lunar eclipse.

There may also be more flash flooding from New York to West Virginia.

Next the danger is around the middle of the month, 13-16 December, with severe thunderstorm activity affecting southern states due to a 'phantom' eclipse i.e. moon and sun both near the true node, whilst no eclipse and near perigee.

In December's third week a storm may affect North and South Carolina.

As a result of latent hangover from the eclipse configuration, the next threats will be 11-14 January in the northwest and Texas.

The heaviest snow in February for the US will be in the west and eastern states, and most of the snow in March is in the west, with snowfalls petering out about mid April.

Ken Ring of www.predictweather.com is the author of Weather Almanac for NZ for 2013, published by Random House.