Understanding summer weather patterns and how they affect the Seaway
During the summer season there are 2 distinct weather patterns, South East and Northerly. Each of these patterns plays a part in the fishing in the seaway, as the water can go from clean blue water to dirty green water in a matter of days. Below we have 2 sea surface temperature pictures, one dated 4th december 2009, and the other 6 days later dated 10th December 2009. Weather patterns are usually cyclic repeating every 6-7 days until a significant change comes through altering the cycle.
The first one (4th December) shows the sea surface temperature after a sustained period of South Easterly Winds. A warm water current (25-26 degrees) has pushed right in close to the seaway and the water was clean and fish were very active with lots of surface feeding by kingfish, bigeyes and tailor. Warm Water currents can also bring in the pelagic species such as Striped, Yellowfin and Mack Tuna, Spotted and School mackerel and bonito. the one caveat to this is that a sustained South Easterly weather pattern is sometimes associated with a cyclone up north. This can bring a deluge of rain and floods which will shut down the seaway for weeks. The Gold Coast can handle about 150mm of rain without much effect, any more than that and it will flood which can wipe out the entire summer season.
The second picture (10th December) just 6 days later shows what happens when a strong northerly weather pattern takes over. A cold water current (21-22 degrees)has slipped up the coast from NSW right up as far as the tip of north stradbroke. This cold water current brings dirty green water right into the seaway and shuts down much of the action. Fish can still be caught but not in the numbers that are around with the clean warm water associated with a South Easterly weather pattern. Northerlies also stir up alot of sand and weed into the water, particularly on the north wall this can be a problem.
The strong winds at this time of year can make fishing the ends of the walls difficult, however prediciting a lull in the wind is quite easy if you know what to look for. Usually when a SE weather pattern switches over to a Northerly pattern, the day of the switch is usually calm with little wind and these days are ideal for fishing as the water is usually clean and with enough wave action so the fish are feeding aggressively. The same lull happens when a Northerly switches over to a SE pattern, though the water is usually dirty.
Current sea surface temperatures can be found by visiting the CSIRO ocean currents page. If you have a look at the current map (2nd September)you'll see alot of warm water in close, this has brung in the pilchards and baitfish and what has increased the level of fish activity in the last few days.