Bobgram

Bob McDavitt’s ideas for sailing around the South Pacific. Disclaimer: Weather is a mix of pattern and chaos; these ideas are from the patterned world. Compiled 23 August 2026 Next three months outlook The latest edition of official Island Climate update is now available from Earth Science niwa.co.nz/climate-and-weather/island-climate-update Basically it says that due to el Niño the south Pacific convergence zone is shifting north and east of its normal position. Another website ( tropicaltidbits.com) shows the 3sep/oct/nov expected rain anomaly A huge dry zone from New Guinea to Niue The averaged weather map over next three months has southwesterly isobars over New Zealand, reasonable SE winds over Tonga to Queensland and a large subtropical ridge with light winds in the Tasman Sea The only spots with lower than normal pressure are out to the northeast of Samoa and to SE of New Zealand. Public holidays One of the yachts I’m forecasting for have had their weather plans upset by a Public holiday in Fiji on Monday (Mohammed’s Birthday). There are lots of public holidays around the various Island sin the South Pacific, several which can catch first-timers out so here is a lit for reference, going roughly from east to west (and ignoring Christmas/Boxing): French Polynesia : 1 Nov: All Saints Day 11 Nov: Armistice Day Cook Islands: 26 Oct: Gospel Day Niue: 19 Oct (likely) Constitution Day Tonga: Thursday 17 Sept: Crown Prince Birthday 2 Nov: National Day 7 Dec: King’s Day America Samoa 7 Sep : Labor day 12 Oct Columbus day/Discovers’ day 11 Nov Veterans’ Day Thu 26 Nov Thanksgiving Samoa 12 Oct: Lotu a Tamaiti/ Kids Day (Mondayisation of White Sunday) Fiji 24 Aug Mohammed’s Birthday 10 Oct Fiji Day 9 Nov Diwali Vanuatu: 5 Oct Constitution Day 29 Nov Unity Day New Caledonia 24 Sep National day 1 Nov : All Saints Day 11 Nov: Armistice Day Norfolk Island Wed 25 Nov Thanksgiving (started by an American whaler there in the 1890s) New Zealand: 26 Oct: Labour Day: Australia Labour day is held on 5 Oct in New South Wales (2 March in WA, 9 March in VIC and TAS, 4 May in Queensland): TROPICS • Hurricane Lala skirted Hawaii, with squalls from its outer bands leaving at least one person dead, roads destroyed and around 100 homes damaged. Lala brought Hawaii some of its most severe tropical cyclone impacts since Category-4 Hurricane Iniki devastated Kauai in 1992. • MOKE is travelling west to south of Hawaii • NARRA , GAENARI and SAUDEL, along with a couple of tropical depression are congregating around China. WEATHER ZONES Weather Zones Mid-week GFS model showing isobars, winds, waves (purple), rain (red), MT (Monsoonal trough), STR (Subtropical Ridge), SPCZ (South Pacific Convergence Zone) CZ (Convergence Zone) SPCZ is north of its normal position High H1 is moving northeast from Tasman Sea around the north of the north island. Then east along 30 to 35S. The squeezes the isobars in the trade winds on its northern side making a SQUASH ZONE between Cook Islands and Tonga by mid-week. Avoid. Low L1 over south Australia is expected to move southeast and cross the south Tasman Sea mid-week then bring troughy conditions to New Zealand by end of the week. Avoid. High H2 is expected to travel east along 30S across Australia reaching Alice by Wednesday then fading as it moves northeast onto Queensland It is expected to be followed by a weak trough and then a large 1036hPa High in the Aussie Bight. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> If you would like more details about your voyage, check metbob.com Or Facebook at /www.facebook.com/metbobnz/ Weathergram with graphics is at metbob.wordpress.com (subscribe/unsubscribe at bottom). Weathergram archive (with translator) is at weathergram.blogspot.co.nz. Contact is bob@metbob.com or text 64277762212. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>