Tawa’s climate during December 2007 was calmer and drier than last year, with temperatures similar to 2003 and 2005.
December 2003 started unremarkably until the air grew heavy and humid late on the 5th, with blustery northerlies increasing to strong gusty nor’easters on the morning of the 6th. Steady rain fell on the 7th, easing to periods of drizzle. Humid conditions on the 12th and 13th hid the hills in fog until the gusty north-east wind cleared the air a little on the 14th. Warm gusty northerly winds arrived on the 25th and increased to gale force the following day while the hills were wreathed in mist. Rain commenced late on the 27th and the 28th was a wild day of thunder, lightning, strong wind gusts with intermittent downpours causing house guttering to overflow. Calm conditions returned on the 29th, and steady rain fell on the 30th as temperatures plummeted to the low teens. Whilst the 31st was sunny, the overnight low of 8 °C was a shock.
December 2004 started with mild conditions, but a strong northerly on the 3rd changed to a southerly gale on the 5th and brought steady rain. Sunny, calm days returned until the 9th when showers of rain fell and overnight temperatures fell into single digits amid cold, damp showery conditions. A clearance late on the 11th saw the overnight low drop even lower to 6 °C.
A northerly gale on the 13th was accompanied by a sickly yellow dusk. Thereafter conditions improved until the 16th, when heavy rain fell. A strong westerly on the 17th brought a sickly yellow dusk again but then cleared the air and was followed by steady rain and strong, cold southerly winds on the 18th and 19th. Calm returned until late on the 23rd when a gusty northerly brought showers which eased to drizzle the next day.
New Zealand had a close call when the strongest earthquake for 2004, a magnitude 8.1 quake, struck west of the Auckland Islands on the 24th. This event was quickly overtaken by news of the even larger Boxing Day earthquake and the associated tsunami which caused much devastation in the Indian Ocean. Weatherwise, the remainder of the month was unremarkable apart from strong nor’westers on the 26th, the commissioning of the automatic weather station at Tawa on the 29th and steady rain on the 30th.
December 2005 began in a fashion similar to the previous year, being calm on the 1st with a gusty northerly arriving on the 2nd, rising to gale force on the 3rd and bringing low cloud and strong gusts on the 4th. The gusty wind changed to the north-west on the 5th, and a spectacular thunderstorm entertained commuters stuck in traffic jams on State Highway 1 and 2 due to a northbound truck which crashed through into southern lanes on Wellington’s motorway at Aotea Quay on the morning of the 6th. Morning commuters were still stuck in the traffic at 10 a.m. as the thunderstorm and its associated downpours eased, allowing heavy lifting gear to clear the motorway lanes.
Milder conditions set in, and fog swathed the vale of Tawa for much of the 13th. Still conditions prevailed until the 19th, with fog closing Wellington International Airport on the 17th, and lurking about the hills of Tawa on the 18th. A gusty northerly brought steady rain on the 20th but eased back late the following day. Misty, showery days predominated until the 26th and the remainder of the month was calm and still apart from gusty northerlies on the 30th.
December 2006 began with dismal cold showers and alternating southerly and northerly winds. A strong northerly blew on the 7th, rising to gale force with showers the next day. As dusk approached on the 8th, a cold southerly change brought a spectacular thunderstorm which could be seen from Tawa. The storm was located in the Tasman Sea just west of Nelson and local residents marvelled at the lightning display which could be seen through the gathering clouds to the west. Children shrieked at the flashes and intermittent booms from the distant storm, but were inside at 9:25 p.m. when another thunderstorm passed overhead.
The cold southerly change brought steady rain and hail fell briefly on the evening of the 9th, before the winds eased overnight. Still conditions applied until a strong northerly arose on the 12th, easing overnight. Gusty northerlies returned on the evening of the 15th, rising to gale force the following day, bringing steady rain on the 17th as they eased. Sunny, still days put in an appearance until steady rain early on the 20th was followed by a northerly gale that evening. Another thunderstorm and a heavy downpour announced the change to a cold southerly just after midnight and conditions eased as the 21st progressed.
Manual observations ceased as Christmas duties intervened until the 29th. The 30th dawned dry but conditions deteriorated as a cold southerly change brought showers during the morning. The southerly became stronger making the 31st as cold, wet and windy as a mid-winter’s day as locals scrabbled in cupboards for heaters that had been “parked up” for the summer season.
December 2007 started with a continuation of November’s fair weather, and a 22-day dry spell wasn’t broken until showers arrived on the 9th, despite a brief period of drizzle the previous day. Temperatures had been cool, with the relatively calm conditions allowing them to fall into the low teens overnight, and a cold southerly dragging them lower on the 6th.
Sunny calm days dominated again, with a brief period of showers on the 13th and steady rain on the 18th, following a change to gusty nor’westers the previous day. A southerly change brought low cloud and periods of steady rain until early on the 20th when the sun returned amid light winds. Strong nor’westerlies on Christmas Eve brought 19 mm of rain overnight and kept most people indoors on Christmas Day.
Boxing Day saw a cold southerly arrive and feeble attempts at a thunderstorm during the afternoon. The sun broke through briefly the next day but a strong northerly arrived that night and the 28th was a drizzly showery day of low cloud and mist in the valley of Tawa. Sunny, calm days then held sway until the 31st, when a strong southerly arrived.
Automatic and manual readings taken at Tawa since 2003 can be summarised as follows:
The lowest December temperatures were 8 °C (2003), 6 °C (2004), 9 °C (2005), 7 °C (2006), 6.5 ºC (2007).
The average daily low temperatures were 14 °C (2003), 11 °C (2004), 15 °C (2005), 11 °C (2006), 13 ºC (2007).
The highest December temperatures were 24 °C (2003), 26 °C (2004), 27 °C (2005), 23 °C (2006), 27.7 ºC (2007).
The average daily high temperatures were 21 °C (2003), 19 °C (2004), 24 °C (2005), 19 °C (2006), 22 ºC (2007).
Average temperature: 18.2°C (2005), 14.4°C(2006), 16.7 ºC (2007).
Average humidity: 81% (2005), 79% (2006), 76% (2007)
Days with frost: none (2003), none (2004), none (2005) none (2006), none (2007).
Days with rain: 16 (2003), 15 (2004), 13 (2005), 14 (2006), 11 (2007).
Days with thunderstorms: 1 (2003), none (2004), 1 (2005), 2 (2006), 1 (2007).
Days with hail: none (2003), none (2004), none (2005), 1 (2006), none (2007).
Days with strong winds: 8 (2003), 8 (2004), 10 (2005), 13 (2006), 5 (2007).
Rainfall: 46 mm (2005), 69 mm (2006), 60 mm (2007).