MODELS AND RAINFALL - A BRIEF LOOK ONCE AGAIN.

Not seeing a great deal of consistency still in the modelling into the short and medium term so anything going beyond about 5 days on the deterministic data sets is not especially reliable at the moment. So I am going to briefly talk about the broader Ensemble data sets tonight and a look at the latest 6 week guide.


ENSEMBLE DATA

These data sets are much more reliable in a broad sense and offer us a glimpse as to what is head beyond this quieter 5 day spell. With the mixed odds from the medium term guidance on a deterministic level, it is much more critical to use these sets as they provide more of an insight into where the moisture is likely to emerge from and where low pressure will be in phase with the moisture. At this time, the tropics look damp with above average rainfall chances. Also watching the MJO on the approach to the northwest of the country with moisture streaming in ahead of this enhanced area of tropical weather possibly seeding the cold fronts and troughs passing over the southern parts of the nation in this period. The positive SAM also in play which could increase rainfall and showers over the east coast of QLD and NSW south of the tropics with the potential of some moderate to heavy falls.


GFS - Rainfall Next 16 Days (median of 35 members) - LOW CHANCE

The northwest wetter and the east drier than the other models you can see below. So at this time the GFS is by itself somewhat, which is not unusual. It just expresses the uncertainty out there in the mid range.

CMC - Rainfall Next 15 Days (median of 30 members) - MODERATE CHANCE

Wetter in the east and over the north with the MJO rolling through and the models suggesting a positive SAM is on the cards. The west drier. Not so sure on that.

EURO - Rainfall Next 15 Days (median of 51 members) - MODERATE CHANCE

Probably a little too dry and reactive to the small scale climate driver. Wetter in the east looks to be gathering pace. The tropics also active and watching for a tropical low near the Gulf of Carpentaria

LONG TERM

Still offering a lot of weather in April and through early May.


CFS - Rainfall Next 6 Weeks - MODERATE CHANCE

Watching the weather turn more active from April I suspect with the battle between the colder air rising north and the moisture and humid air lingering thanks to the wet season and La Nina waning, playing out through the continent.