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 18 October 2026 Welcome to an early start to this new cyclone season. TC WATI is visiting Southern Cooks on their Sunday. Earth Sciences New Zealand is predicting a busy cyclone activity for those parts of the Pacific east of the date line, especially for French Polynesia. This report was developed with contributions from New Zealand's MetService, the University of Newcastle in Australia, and various Pacific Islands met services . For north, central and northeast areas - including Samoa, Tokelau, French Polynesia and parts of Kiribati - there is an elevated risk. . For north of the Coral Sea and the west central area of the southwest Pacific, including Fiji and Tonga, near normal activity is forecast. . For New Caledonia and Vanuatu - there is a normal to reduced risk. The main factor this year is a very strong El Nino. This is a climate driver that affects tropical weather and it is breaking records this year And here is what the Quasi Biennial Oscillation QBO was doing in those years (diagram) In a strong El Nino, the rising air of the equatorial WALKER circulation has shifted and is now near the dateline This puts French Polynesia downstream of a zone of rising motion Henec the following evaluations of possible cyclone activity for the coming season: https://www.earthsciences.nz/news/normal-to-above-normal-tropical-cyclone-ac tivity-expected-for-the-southwest-pacific TROPICS .Hurricane Isaias raked northern Florida's Gulf Coast with 105- mph winds, killing eight people and cutting power to nearly a million customers. The storm also unleashed destructive flooding and tornadoes across the southeastern United States. . Hurricane Simon battered Mexico's Pacific coast, killing one person. . Tropical Storm Rachel brought deadly flooding to Baja California and damaged seaside homes in Southern California with huge waves. . TC CHAMPI is heading for Taiwan. 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 mainly north of 10S and rather weak. TC WATI gets close to Southern Cook Islands on local Sunday and then is expected to move off to the southeast. High H1 is expected to travel slowly NE across the Tasman Sea and then travel east along 35S early next week. This offers a good opportunity for sailing from the tropics to Australia or New Zealand. It also enhances the easterly winds between Fiji and Vanuatu and about Samoa. Low L2 is slowly following H1 and is front is, at this stage, expected to reach Brisbane to Northland around Thu 29 Oct , ending this good-looking window for sailing from tropics to Australia/New Zealand. After this and a few days of southerly swell the next HIGH is expected to enter the Tasman Se around 30/31 Oct, opening another window for sailing out of the tropics. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>

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 11 October 2026 FEEDSPOT My weathergram blog started in 1995 in response to the storm that affected the 1994 Auckland to Suva yacht race. It has recently been selected to join the Top 80 Weather Blogs on the web (2026 edition). https://bloggers.feedspot.com/weather_blogs/ Feedspot is an RSS Reader that lets you subscribe to blogs, news sites, and any website you want to keep up with. This is a proud achievement. And if you have time please check the link to the Top 80 I'm sure there are some sites that will help you. Sea Mercy The coming Cyclone season may well start early with the cyclone risk already building in the Samoa area. The next MJO is expected towards the end of November, but things may kick off before then, as some models already have a tropical low forming near Samoa. If you intend to stay in Fiji this cyclone season and are willing to help out in the event of a natural disaster, then consider contacting SEA MERCY at https://seamercyfiji.org On the past 10 years they have managed over 100 volunteer yachts to provide assistance around affected Islands. TROPICS * Hurricane Isaias weakened quickly upon landfall in Florida. * The western Pacific typhoon season remained extremely active, with Nolo, Choi-Wan and Koguma churning the ocean. * Hurricane RACHEL and SIMON lost force off Baja California. WEATHER ZONES SPCZ is mainly north of 10S. Low L2 over Tuvalu by mid week may deepen near Samoa by weekend. HIGH H1 east of NZ and south of Tahiti is quasi-stationary and blocked a couplet of lows west and east of NZ last few days. Those lows have now faded leaving behind a disturbed westerly flow with some leftover rain bands. This High has also been enhancing the trade winds between Tahiti and Fiji. Low L1 is traveling quickly beast along 45s and associated FRONT is expected to reach Brisbane on Wednesday, and Northland on Thursday. A day or two of southerly winds following that front is expected to get north to Noumea/ Minerva by Saturday. So, If in Fiji or Tonga then maybe stay put until that southerly comes and goes. If in Noumea, then there are some reasonable -looking voyages departing between Monday and Wednesday to NZ if you are bold enough. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>

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 04 October 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 https://youtu.be/6j7UxmBp9a8 Several anticyclones entered the south Tasman then travelled northeast and then faded into the subtropical ridge along 30S. This pattern repeated 1-3 Sep 14-16 Sep 24-26 Sep and 29-30 Sep. There continue to be several near equatorial lows , a facet of this El Nino. In an El Nino the Walker Circulation over the Pacific equator shifts so that its rising pillar gets close to 180deg/Kirimati. The 500hPa heights and anomalies shows that prolonged upper low over Tasman sea late in the month From 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 continues, and that cooler patch on its southwest side over Southwest pacific is bringing dry conditions . Average isobars for past month From www.psl.noaa.gov/map/images/fnl/slp_30b.fnl.html In the northern hemisphere the Siberian anticyclone is forming quickly heralding an early winter there. The Pacific equatorial Low and Tasman High have intensified, as expected in El Nino. Pressure anomalies for past two months From www.psl.noaa.gov/map/images/fnl/slp_30b.fnl.html The anomaly pressure pattern hasn't changed much in the past month. New Zealand Details The 1020 isobar has shifted south over Tasmania. The saddle point between NZ and Chile has dropped from around 1017 to about 1013. The SAM Southern Annular Mode ( as shown using the AAO) was positive in September and is forecast to be neutral or positive for much of October TROPICS . Hurricane Polo made landfall on the Baja California peninsula, knocking out power as it brought life-threatening rain and winds to northwestern Mexico. Its tropical moisture also triggered widespread flooding across the southwestern United States. . Hurricane Rachel skirted Mexico's Pacific coast. . Hawaii's Big Island was soaked by Hurricane Nolo. . Typhoon Surigae became the second such storm to skirt Japan's Honshu Island in just over a week. . Tropical Storm Gonzalo formed briefly 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) High H1 east of NZ tonight is expected to travel off to the northeast There was a cold pool trough between Norfolk and Noumea on Friday Thar has been an easterly punch cold front over Northland today, pushed quickly north by H1. This cold air is expected to meet the left over cold pool and forma a surface low south of Minerva by Tuesday and that should fade as it moves southeast by Thursday. Low L2 is expected to enter the Tasman Sea from the west as a trough on Tuesday and then form on Wednesday and become blocked and pushed off to the north on Thursday and Friday as High H2 travels east along 45S. L2 then travel southeasts , decaying over the North Island by next - and followed another Tasman trough early next week. >>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> 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. >>>>>>>>>>>>>>>>