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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 30 August 2026 Ocean warmth breaks to 70degrees F barrier Full story is at climate.copernicus.eu/copernicus-daily-global-sea-surface-temperature-breaks -2024-record Note that an August maximum is usually lower than the March maximum. Not this year. And this El Nino is expected to get stronger next few months Of particular interest in our region is the moat of cooler than normal sea between New Guinea and Niue . The South Pacific convergence zone has shifted well north and east, and Fiji/Tonga are approaching drought conditions. Logically the cyclone risk this season is also likely to shift north and east. More on that later in September. As for how this impacts the Island hoppers from Tonga to Tahiti: Well, this coming week shows a typical el Nino pattern over the South Pacific , with strong west to southwest winds south of 30S, an expansive subtropical ridge between 20 and 30S, thundery squalls north of 15Sz. Also there is a tendency for secondary lows to form on fronts as they cross New Zealand (as happened 29 Aug and may happen on 11 Sep. And a tendency for tropical lows to form on the NW shoulder of the migratory Highs as may happen around 6 September rover Austral Islands TROPICS . Downpours from Tropical Storm Narra battered northern Vietnam and China's Guangxi region with floods and landslides. . Typhoon Saudel drenched some of Japan's southernmost islands before taking aim on coastal China. . Passing Tropical Storm Moke brought locally heavy rain to Hawaii while Iselle and Julio spun up to the east, followed by Karina and Lowell. WEATHER ZONES SPCZ is north of its normal position High H1 is moving east along 30S south of French Polynesia. L1 belongs to a broad trough that crossed NZ last few days. A following trough is expected to cross the south of NZ on Monday with strong southerly winds and snow to low levels. High H2 over Tasmania tonight is expected to travel northeast into the Tasman Sea /30S region by Wednesday. L2 follows on the south side of H2, and is likely to broaden outwards into three different troughs crossing NZ on 6, 8, and 11 Sept. There is a chance of a secondary forming over North Island on 10 Sept. Avoid arriving in NZ on the day of a passing trough. Low L3 is expected to start forming on Friday near Rarotonga. It may deepen quickly near 30S as it moves off to the southeast and produce a zone of light winds on its northern side. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

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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. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

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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 16 August 2026 Lala land Rare Hawaiian cyclone. Cyclone Lala earlier today just missed Hawaii's Big Island Cyclone Hernan is closely following. . Typhoon DOLPHIN: After traveling 3,700 miles across the Pacific over two weeks, former Category-5 Typhoon Dolphin roared ashore in China's Zhejiang province, just south of Shanghai. The storm prompted mass evacuations and disrupted travel before carrying heavy rainfall well into the interior of China. . Tokyo and other parts of central Japan were raked by Tropical Storm Chan-hom. . Tropical Storm Cristobal formed in the Atlantic, west of the Azores. . LALA travelled westwards towards Hawaii, followed by Herman. WEATHER ZONES SPCZ is returning to a more normal position between Solomon Islands and Samoa. There is a weak low L1 lingering to the northeast of the Solomon Islands, but not doing much. Associated convergence zone/trough tonight southwest of Fiji and over Tonag is expected to cross Niue /southern Cooks next few days. After that there seems to be a good period for Island-hopping westwards. Low L2 east of the North Island is spreading a southerly burst northward towards Tonga next few days. High H1 over Tasmania up to 1040hPa on Monday is expected to cross the south Tasman by mid-week then go northeast and be north of Northland by week's end. This is looking good for anyone planning to sail westwards across the Tasman sea. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

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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 09 August 2026 Cauldron boil .. Sea surface temperatures as El Nino warms the Pacific.. Cauldron bubble ---- Cyclones spin around each other .. As seen at cyclocane .com The Northwest Pacific is having a busy time with 3 cyclones circling each other at present. An incoming positive phase of MJO is expected to bring extra bubbly clouds (blue) to the NW Pac over the next few weeks TROPICS . Former Category-5 Typhoon DOLPHIN passed directly over remote and uninhabited North Iwo Jima, the first time an eye of a typhoon was ever observed making landfall there. The storm later raked Okinawa and other southern Japanese islands, and was taking aim at China's Zhejiang coast. . CHAN-HOM is heading westwards for Japan but spinning to the left under influence of DOLPHIN . Slowly moving Tropical Storm KUJIRA drenched the northern Philippines and is now travelling to northeast, but spinning to the left under influence of CHAN-HOM. WEATHER ZONES SPCZ is north of normal. Low L1 near Kermadecs on Monday is expected to travel northeast along with Highs to north and south of it. This is expected to produce an enhancement in the trade winds over Austral and Cook Islands for a few days.... a squash zone. Wait for it to ease off before Island hopping. Low L2 is has brought ample rain recently to SE Australia, followed by cold southerlies, and is crossing Tasmania tonight. It is expected to unravel in the Tasman Sea and associated front should cross NZ on Wednesday/Thursday--- This trough is expected to stall near Northland this weekend. Take care. HIGH H3 approaching Perth by Wednesday is expected to travel ESE along Aussie coast and reach Tasmania by end of the week. Tropical Low L3 may form off east end of Solomon Islands by this weekend and travel slowly south producing a squash zone of wind and rain over Vanuatu by weekend and maybe over Fiji next week (they can do with some rain). >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>

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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 02 August 2026 A review of last month's weather Here is a link to a YouTube clip giving an animated loop of the isobars and streamlines For last month is at youtu.be/rB2Adl_wxt0 Most of the month brought winter anticyclones to New Zealand, but a cold pool produced a deep fast-moving low on the 7th. Notice the lows forming near the equator and in mid -Pacific.. This is consistent with the rapidly intensifying El Nino. In an El Nino the Walker Circulation over the Pacific equator shifts so that its rising pillar gets close to 180deg/ Kiribati. The 500hPa heights and anomalies shows that prolonged upper low over Tasman sea late in the month can be seen at http://www.cpc.ncep.noaa.gov/products/intraseasonal/z500_sh_anim.shtml Sea Surface temperature anomalies from psl.noaa.gov/map/clim/sst.shtml El Nino 's warmth in the eastern equatorial pacific is intensifying , and that cooler patch on its southwest side over Southwest pacific is bringing intensifying dry conditions . The march towards El Nino in the Equatorial Eastern pacific may be seen in a Time /Long plot for 7 degrees around the equator The equatorial current has turned into an east-going river up to 3kt in places. Average isobars for past month (below) The Indian Monsoon stuttered a bit last month and accumulated a 15% deficit in rainfall in the season-to-date. The subtropical ridge has weakened a lot between Tahiti and Chile. Pressure anomalies for past two months (below) The anomaly pressure pattern for last month shows a low breeding area northeast of New Zealand extending to Easter Island. This is an indicator that French Polynesia may have periods of unsettled weather over the next few months Previous month below Last month above The 1020 isobar is in much the same place as last month over Australia but has retreated westwards over New Zealand, and disappeared further east. TROPICS . Typhoon Noul: After leaving three people dead in the far northern Philippines, Typhoon Noul lashed Hong Kong and China's Guangdong province with sustained winds of up to 101 mph, downing trees and utility lines. . Hurricanes Fausto and Genevieve passed westward across the eastern Pacific without directly affecting any land areas. . Super Typhoon Dolphin intensified to Category 5 force over the open waters of the central Pacific, north of the Marshall Islands. WEATHER ZONES Low L1 near Kermadecs tonight is expected to travel southeast and associated front/convergence zone should cross Niue /southern Cooks /Society Islansd s next few days--- not much in the way of showers but a wind change to NE then S/SE and an increase in southerly swells. Low L2 is expected to travel to NE east of NZ next few days, shovelling southerly chilled air northwards. This makes High H1 which follows it mid-week across New Zealand FROSTY. Next week, when H1 gets east of NZ, I expect it to intensify and enhance the trade winds between Tahiti and Tonga. Low L3 is expected to move north-eastwards across Tasmania on Monday and eastwards across the Tasman this week then southeast over southern NZ late in the week, followed by High H2. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>