Compiled Sun 24 Feb 2019
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.
A TROPICAL BLAST
I took some snap shots of a cloud feature I spotted last Thursday in the Coral Sea, to the northwest of TC OMA:
It is as if something has triggered a blast from the centre of this cloud feature, causing squall lines to move out to west, south and east in a radial fashion. Fascinating to watch.
I made a video of the event using the one-hour time stepped imagery available from New Caledonia Met site: www.meteo.nc/nouvelle-caledonie/observations/images-satellite
This video is available at tinyurl.com/tropicalblast
TC OMA moved a little slower than the computer models were picking, and consequently it missed an opportunity to be steered to New Zealand --- however the upper winds did vent a lot of its higher clouds to New Zealand bringing the blessing of some much-needed rain.
TC OMA edged close to southern Queensland from Friday and brought gusty southerly winds.
Gold Coast Airport was gusting over 40 knots on Saturday. Gale winds affected exposed coastal places. OMA has been downgraded now, but may make landfall over New Caledonia as it goes north over next few days, and there are still strong winds and heavy swells long the southeast Queensland coast.
This month the moon was closest it will get this year to earth on Feb 19th (357,012km) and the resulting King tides a few days later, boosted by a strong onshore flow/ storm surge thanks to OMA brought the sea inundating Gold Coast streets.
As mentioned in last week’s blog, TC OMA has triggered a twin cyclone in the northern hemisphere (spurned by the near equatorial westerly winds) This is TC WUTIP and it is expected to strengthen next few days to CAT 4 as it passes to southwest and west of Guam and then to weaken as it travel northwest towards the Philippines.
There is also a tropical depression forming to northwest of Samoa, TD 95P. Its future is uncertain at this stage.
Latest cyclone activity as at tropic.ssec.wisc.edu and TCFP tropical Cyclone Formation Potential as seen at www.ssd.noaa.gov/PS/TROP/TCFP/index.html
The weekly rain maps for the past 2 weeks clearly shows the slow path of TC OMA and TC WUTIP. The South Pacific Convergence zone has had an active week between Samoa and French Polynesia.
SPCZ=South Pacific Convergence zone.
The movement of TC OMA to the south has disrupted the monsoonal trough. The SPCZ now stretches from northwest of Samoa to south of French Polynesia. TD 95P is now on the SPCZ and its future uncertain, but if it deepens it is expected to dominant the South Pacific this week and travel south affecting Tonga. The SPCZ is on the northeastern edge of the monsoonal trough, and likely to stretch from Samoa to French Polynesia this week.
Subtropical ridge (STR)
HIGH in central Tasman sea on Monday is expected to cross central NZ on Tuesday.
Next HIGH is expected to travel eastwards across Tasmania on Wednesday and then onto northern NZ on Sun 3 March .
Australia/Tasman Sea / New Zealand
North of 30S, too much in the way of SE wind for departing east from Australia this week, but may be Ok for going westwards.
Further south it is looking OK for getting east.
Panama to Marquesas
There were only light winds around Panama last week, but the forecast is for more useful northerly winds from local Sunday to Wednesday, and then light winds again from Thursday to Sunday.
Port Vallarta to Marquesas
There may light winds for a Monday start, and better winds for a start on local Tuesday and Wednesday, then light winds again. Weak ITCZ likely between 5N and 2N, and there may be a “mirror CZ” near 3 to 4S.
If you would like more detail for your voyage, then check metbob.com to see what I offer.
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