May 2023 Outlook SA
May 2023 outlook SA
*Forecast prepared between May 1st-4th 2023
Review:
G’Day everyone, I hope you are keeping well and have had
a good Easter and April in general. May is now here and is no doubt a very
important month in your seeding programs among other things and certainly a
time when we all look to the heavens with a vested interest.
Firstly, we will look back on April and all in all it
turned out better than we initially expected which in a way is a double-edged
sword. On the positive front, we managed to get some extra moisture into the
soil ahead of temperatures and evaporation numbers dropping but on the negative
side it also means the dry spell and downwelling period will be shifted 3-4
weeks into the future. We did see the early signs of significant high pressure
through mid to late April with a block of 4-5 days from the 19th to
23rd where the pressure held up around 1029hPa which is quite a feat
in April and an early hint of an expanding Hadley cell with greater
downwelling. But as we know, all long term and broadscale pattern changes don’t
just happen in one instant, they take multiple efforts and attempts to break
down the old pattern and bring in the new one and this case is no different.
Part of this slow breaking down has allowed some tropical
influence to remain and the most recent MJO was a strong one giving extra
tropical moisture to Northern Australia. This also timed well with significant
cosmic activity from the sun causing wild fluctuations in the jetstreams and
promoting more cut off attempts but overall, the systems were not all that
significant.
We finished the month with a little burst of rain but the
focus was mostly to the southern agricultural areas as opposed to northern and
eastern with rain shadow playing a big part in reducing rainfall to the east
and the lack of tropical connection in the post ANZAC Day event, causing a big
reduction in totals for areas north of about Clare in particular. There were
however some isolated handy totals with Lower Eyre Peninsula getting some
thunderstorms to boost things up as well as a lot of this sliding over KI with
20-30mm totals in both districts. In the colder air behind some streams did set
up off the Spencer Gulf into the far N Yorke Pen and western Lower North/Upper
North with some 5-10mm totals.
Now to look at April rainfall in terms of the charts:
Figure 1: April 2023 rainfall deciles – source BoM http://www.bom.gov.au/climate/
Figure 2: April 2023 rainfall percentages – source http://www.bom.gov.au/climate/
Figure 3: April 2023 rainfall anomalies – source BoM http://www.bom.gov.au/climate/
Now going back to
the original April outlook and we can see how we performed:
“Now to the all-important rainfall outlook for April.
With the wetter window for the first half and drier for the second I think
broadly we are looking at average to slightly below average for the
agricultural areas. The greatest chance of popping above the average will be
over the West Coast/Far West of the state, NW corner and potentially the
southern coastlines of EP, YP, most of KI and the coast of the Lower SE. The
NW/W of the state especially sees the greatest chances. As we move east and
north however across the agricultural areas towards the Upper North and indeed
the NE Pastoral, the odds of below average rainfall increase. The NE corner
will have the greatest chances of below average to well below average
rainfall.”
Broadly speaking, the pattern was reasonably correct with
a wetter tendency towards the NW and W of the state but a drier and below
average tendency towards the eastern portions, especially the Southern NE
Pastoral and Mallee/Riverland areas immediately east of the ranges where rain shadowing
was more prominent. The slightly wetter coastal fringes signal was also
identified however the greatest error was in the spread of slightly above
anomalies across portions of the Upper North, far eastern border areas of the
Mallee and Upper SE and also the bigger heavier
blob over the NW Pastoral which stood out. From previous months expectations we
did trend later with our dry spell by 3-4 weeks as mentioned which allowed
slightly better performance in April. Still, a better performance across all agricultural
areas would have been appreciated, especially those areas east of the ranges.
Meteorological Discussion:
Now we turn our attention to May which as you are
certainly aware, is an important month when it comes to dictating where we are
trending to this season. I have been mentioning a dry spell for quite a while
since late last year to occur from mid-April through May and at this stage we
have only just started to see the hints of that in later April but it should
start to show it’s hand a lot more through May, certainly the first half at
least but potentially a little longer with it being broken up into two sections
and I will explain further down.
The current point in the pattern is the at the pivot of
increasing with subsidence (downwelling) with increasingly larger and stronger
high-pressure systems with less potential for strong lows, trough systems and
general rain bearing systems that have overland carry with rainfall being more
confined to onshore flows of Southern Maritime Air from weak fronts and troughs
favouring areas that are on windward slopes and coastal fringes as well as
Southern extent. So, in short, the further north you get, the drier it should
become but especially so east of the ranges which will compound that. Why is
this happening you might ask?
Essentially it comes down to a
number of things but primarily when we break down out of a La Nina pattern,
there is an expansion of the Hadley cell over Australia and the Tasman Sea
areas. The usual strong trade winds over the Pacific slow down and in patches
reverse with those Westerly wind bursts over the Tropics. The strong warmer
signature off Peru shows very clearly that we are pushing closer to El Nino in
the ocean than La Nina right now and that response is already being felt in the
atmosphere in a stepped process. But that is not the only part given most of
our weather in SA and SW VIC is influenced by both the Indian and the Southern
Ocean far more than the Pacific. The cleanout of the tropics over the Indian
Ocean as the monsoon retreats with dominant easterlies and SE flows across Australia
can re-enforce offshore flows off WA and Indonesia and can bring a complete
destruction or shift in the Leeuwin Current and generate a Ningaloo Nina. This
is happening this year and can be clearly seen in the SST imagery in Figure 4
in the climate driver's section.
Now with the expanding Hadley cell we can generally
expect a suppression of the fronts and more positive SAM activity which in
winter isn’t ideal however I still expect frontal action through winter and
hence why I still expect areas primarily south of Goyder's Line to be
relatively ok as there should just be enough in the fronts (between the strong
highs and frosts) to conjure up enough of a season but north of here and I
think the constant lack of regular rainfall coupled with above average frost
will turn the screws a lot more with these areas. When we do have the negative
bursts in the SAM, I do expect the cold fronts to be vigourous with a lot of
wind and cold air behind, then replaced by strong highs which will act to bring
that cold air aloft to the surface and increase the chances of moderate to
heavy frost, especially for the Upper North, Riverland and Mallee areas where
the air will already be drier.
So far this month in the first 3 days we have managed
some cool onshore weather with weak troughs and a weak front passing through
with a few showers, some settling into streams with heavy showers about on the
2nd with cold air aloft but this was short lived and totals were
sporadic, the heavier ones being more confined to parts of the Adelaide suburbs
and Mt.Lofty Ranges.
We will see another cold burst move up from the SW on the
5th as a cold front and associated upper trough quickly stands up
with some rather cold air aloft. The bulk of this cold air will be better aimed
at VIC and TAS as opposed to SA with only the SE corner of the state receiving
anything of real use from it.
The cold front should reach KI by approx 430am and into
Adelaide by 930-10am with a band of showers but will slow down to struggle to
reach the Riverland till late afternoon and by then the entire band will be
weakening fast and breaking up. Isolated to scattered showers will follow the
front, chiefly over Central Districts before the guts of the upper trough and
pool of cold air aloft move up from the SSW on the 6th through the
day. The bulk of the shower activity will blast through the Lower SE with small
hail expected SE of about Adelaide. Some slight afternoon solar radiation and
heating into the boundary layer will promote convection and produce a little more
penetration up off the Lakes into the SW Mallee and up the back side of the
ranges before a rapid decaying of showers on sundown with only more coastal and
weaker showers remaining as both the mid-levels will warm rapidly as the cold
air moves away but the surface remains cold, hence capping the clouds and
reducing their potential growth.
The next high will be the first in a series of strong
highs and this one will bring the frost after such cold air aloft, it will
simply cause strong subsidence over many days and consequently, no shortage of
frost is on the cards, but mainly to inland and prone areas to begin with. The
risk being so early in the season is for a slight frost, but one needs to at
least be aware that this is a possibility. The main two mornings I am expecting
is the 7th and 8th but also 9th may deliver
one. The Lower SE at least may have some pockets of cloud on the 7th
to mitigate the frost potential, but it will not be the case much further
inland.
Now this high will be a 1039hPa whopper, not the biggest
we can see but for May, this is fairly high end.
Only in the dry years have I seen highs this large through late autumn, and if
they happen in August, then it is a cause for concern as that is the month
commonly known to give the strongest in dry years. The very worst years extend
these values into September and October, but we do not expect it to be in that
category this year.
This high will dominate the state until about the 11th
when a trough and cut off low will attempt to develop in the Bight or somewhere
in that vicinity. If the cold air can push up north enough over WA then the cut
off should hold in the Bight and at least generate some bands of showers about
West Coasts and Eyre Peninsula at first and then the remainder of the
agricultural areas as it moves eastwards through till about the 13th
or 14th however if the muscle of the inland ridging proves too
strong (and we will have an favoured area of upper ridging inland), then this
system may get deflected SE a little earlier in the piece and only bring more
coastal showers to Lower EP, YP, Fleurieu and of course KI as it dives away. If
this system does hold (quite important for some rain) then I’ll issue a sep
quick update for it however if this does not deliver then the next high will
likely take hold and repeat the process of the first, 1033-1035hPa sort of
range with fine, settled conditions but with some frontal impingement starting
to rear up off Perth as the Longwave trough begins to close in there mid-month which will potentially affect us a
couple of days after if the Tasman blocking high moves on. It could also get
quite warm ahead of this next longwave as the inland warmth would have had time
to build up and not be cleared out.
In years like this, we do have the potential for some
weak omega blocks which when looked at through a mid-level 500hPa chart, looks
very much like the Greek omega symbol with two smaller lows either side and a
firm upper ridge down the middle.
WA at least should receive some useful rainfall from this
cut off low and cold air, however I do envisage gaps not far inland from the
south coast.
Now to the all-important May outlook and it should come
as no surprise that there have been no changes to this thought process from
many months ago. It will be a dry month broadly speaking, especially inland
where the onshore flows will struggle to penetrate with any regularity. As a
result, I see below average to well below average rainfall across the Pastoral
Zones, especially however over the N and NE. General below average rainfall for
Northern EP and the Upper North and right down through the Riverland and much
of the Mallee. Most other areas will be slightly below average overall on
windward slopes and coasts and down to the Lower SE. I cannot see any above
average rainfall this month however the mostly likely location to get at least
their average will be Lower Eyre Peninsula and KI.
I have stated that I expect the April-August period to be
below average and that has not changed either, with April starting the period
well but I do worry about May and July at this stage. June and August may bring
more frontal westerlies at least. Spring outlook looks much the same with below
average rainfall, especially early in Spring. Late spring into summer may
finally see some trough systems with thunderstorms (which is normal) but may be
regular enough to provide some rainfall however nothing like last year where we
had such formidable thunderstorms through November.
Climate Drivers
Now I know I have touched on the climate side of things
in the previous section but thought I’d still provide the details in here as
well for those of you who like to quickly jump to one section or another!
The Pacific is really starting to fire up that El Nino
signature now...whether or not the final outcome becomes a Modoki or a standard
one remains to be seen but there is no doubt in my mind that is where we are
heading when you add up all the pieces to the puzzle on the going ons in both
the atmosphere and oceans atm. The Humboldt Current off Peru as mentioned has
been crushed and replaced with enormous warming and this has been consistent
for weeks. I see no changes there in the coming weeks ahead, but with further
warming along the equator extending westwards. Looking at the sub-surface we
are going to see those warm anomalies surface soon which will show up as a
rapid spike of warmth down the equator.
The Coral Sea remains warm and so does the Tasman Sea so
once we get colder air aloft moving in from the west combined with extra high
pressure, do not be surprised to see a rapid uptick in East Coast Low (ECL’s)
as we move into late autumn and especially early winter.
In other news though, the Gulf Stream is very prominent
across the Atlantic with the classic signature sweeping up towards Spain and
the UK so take heed for a humid and thundery summer ahead over there.
Figure 4: Current SST anomalies – note the warmth off
Peru with a westward ‘spike’ starting – source BoM
Looking to the Indian and we can see no major changes in
the oceans at least over the last 2 weeks or so but it is important to note
that the persistent cooler water off WA is a sign of a weak to moderate
Ningaloo Nina and these typically peak in May before breaking down slowly. This
will affect the potential for moisture feeding into this state as it is smack
bang in the zone for our best NW cloudband infeed zone.
Now something that has caught my eye is the squeeze in
the westerly flow through the northern Indian which is likely to induce a Bay
of Bengal Tropical Cyclone. Typically, in the wake of these, we see a large
cooler blob of SST anomalies appear and this shuts down warmth moving south
through that part of the Indian and can combine with cooling off Sumatra once
the stronger trades and deep-water upwelling establish there, bringing out the
positive IOD. This sequence happened in 2020 which smashed an attempt at a
negative IOD very quickly. I envisage 2023 still being that moderate strength
positive IOD but with a slightly earlier peak as the really
powerful ones peak in October with this one
should peak closer to August to possibly September.
The MJO is currently weak over the Western Indian Ocean
and should pass over the mainland in a weak to moderate state through early to
mid-month. I expect this burst to keep pushing back into the Pacific as the
trades are weaker than the last 2-3 months and this will further enhance the El
Nino development. It takes multiple Westerly Wind Bursts (WWB’s) to set up an
El Nino. The strong winds atm over the Indian that will squeeze up and wrap
into the Tropical Cyclone in the Bay of Bengal are a portion of this MJO, but
the overall speeds are folly to the strength given it is more of an isobaric
gradient squeeze rather than a strong wave.
The SAM will show its muscle in May with a strong
positive trend. High pressure will dominate this month over the course of 31
days leading to a long period of the index remaining well above zero. I will be
surprised if it spends more than 4-5 days below the zero line, and honestly
maybe none at all. The only possible chance is
right near the very end of the month as we enter a slight window for moisture
and low pressure but that may be biased towards WA at this stage.
Districts:
Eyre Peninsula
Cold front due mid-morning on 5th with band of
showers, becoming more isolated further inland later. Scattered showers to
follow about Lower Eyre Peninsula with some colder air on 6th but
conditions quickly moderating. Cold SW to S winds across the district in wake
of the front. Strong 1036+hPa high moving slowly across the state after with
crisp nights and cool to mild and mostly clear days. Slight frost risk well
inland 7th and 8th mornings. Weak cut off low to develop
through Bight area on 11th with some bands of showers, chiefly over the coastal
portions of the West Coast and Lower Eyre Peninsula with drier conditions
inland as low gets consumed by the high pressure. Conditions beginning to clear
by 13th as new high begins to develop once more from the west.
Potential for another trough system just after mid-month extending from the
west. Rainfall for period 3-6mm generally, decreasing to less than 3mm inland.
Isolated falls to 10mm about the West Coast and Lower EP.
Upper North
Cold front due late afternoon on 5th with band
of showers, becoming more isolated further inland later, especially overnight
and east of the ranges. Localised stream forming off the top of Spencer gulf
may direct a localised area of showers into the Melrose area and surrounds.
Isolated showers to follow with some colder air on 6th but
conditions quickly moderating. Cold SW to S winds across the district in wake
of the front. Strong 1036+hPa high moving slowly across the state after with
crisp nights and cool to mild and mostly clear days. Slight frost risk 7th
and 8th mornings and also potentially
the 9th as well. Weak cut off low to develop through Bight area on
11th with some bands of showers developing later and into the 12th though
likely quite isolated here with drier conditions further inland as low gets consumed
by the high pressure. Conditions largely clearing by 13th as new
high begins to develop once more from the west with a resumption of cold
nights. Potential for another trough system just after mid-month extending from
the west. Rainfall for period 2-3mm generally, decreasing to less than 1mm
inland. Isolated falls to 8-10mm in streams up to Melrose potentially.
Lower North
Cold front due early to mid-afternoon on 5th
with band of showers, becoming more isolated further inland later, especially
overnight and east of the ranges. Localised streams may briefly setup overnight
though not a lot in it. Isolated showers to follow with some colder air on 6th
but conditions quickly moderating. Cold SW to S winds across the district in
wake of the front. Strong 1036+hPa high moving slowly across the state after
with crisp nights and cool to mild and mostly clear days. Slight frost risk 7th
and 8th mornings and also potentially the
9th as well. Weak cut off low to develop through Bight area on 11th
with some bands of showers developing later and into the 12th though likely
quite isolated here with drier conditions further north towards the Upper North
as low gets consumed by the high pressure. Conditions largely clearing by 13th
as new high begins to develop once more from the west with a resumption of cold
nights. Potential for another trough system just after mid-month extending from
the west. Rainfall for period 3-4mm generally, decreasing to less than 1mm
towards backs of ranges. Isolated falls to 7-10mm in streams or about the more
southern portions of the district near elevated terrain.
Yorke Peninsula
Cold front due mid-morning on 5th with band of
showers, becoming more isolated further north later although narrow local
streams may set up off the gulf. Isolated showers generally to follow with some
colder air on 6th but conditions quickly moderating later in the
day. Cold SW to S winds across the district in wake of the front. Strong
1036+hPa high moving slowly across the state after with crisp nights and cool
to mild and mostly clear days. Slight frost risk towards the north of the
Peninsula on 7th and 8th mornings. Weak cut off low to
develop through Bight area on 11th with some bands of showers at times,
becoming more isolated as drier conditions develop as low gets consumed by the
high pressure. Conditions beginning to clear by 13th as new high
begins to develop once more from the west. Potential for another trough system
just after mid-month extending from the west. Rainfall for period 4-8mm
generally, decreasing to less than 4mm in the north. Isolated falls to 15mm
about the foot of Yorke Peninsula.
Kangaroo Island
Cold front due early before dawn on 5th with
band of showers. Isolated showers generally to follow with some colder air on 6th
but conditions quickly moderating later in the day. Cold SW to S winds across
the district in wake of the front. Strong 1036+hPa high moving slowly across
the state after with crisp nights and cool to mild and mostly clear days. Very slight frost risk towards the centre of
the island on 7th and 8th mornings. Weak cut off low to
develop through Bight area on 11th with some bands of showers at times,
becoming more isolated later on 12th as drier
conditions develop as low gets consumed by the high pressure. Conditions
beginning to clear by 13th as new high begins to develop once more
from the west. Potential for another trough system just after mid-month
extending from the west. Rainfall for period 5-10mm generally, decreasing to
less than 4mm in the north of the island. Isolated falls to 15mm about the
western end and potentially southern coast.
Adelaide Plains
Cold front due mid-morning on 5th with band of
showers, becoming more isolated further north later although narrow local
streams may set up off the gulf into the northern plains briefly. Isolated to
scattered showers generally to follow with some colder air on 6th
but conditions quickly moderating later in the day. Cold SW to S winds across
the district in wake of the front. Strong 1036+hPa high moving slowly across
the state after with crisp nights and cool to mild and mostly clear days.
Slight frost risk towards the outer plains on 7th and 8th
mornings. Weak cut off low to develop through Bight area on 11th with some
bands of showers at times, becoming more isolated on 12th as drier conditions
develop as low gets consumed by the high pressure. Conditions beginning to
clear by 13th as new high begins to develop once more from the west.
Potential for another trough system just after mid-month extending from the
west. Rainfall for period 5-10mm generally, decreasing to less than 5mm in the
north and about western suburbs. Isolated falls to 10-12mm about the foothills.
Mt.Lofty Ranges
Cold front due mid-morning on 5th with band of
showers, becoming more isolated further north later although narrow local
streams may set up off the gulf into the northern ranges briefly. Isolated to
scattered showers generally to follow with some colder air on 6th
especially towards the Southern Ranges and off the back of them but conditions
quickly moderating later in the day. Cold SW to S winds across the district in
wake of the front. Strong 1036+hPa high moving slowly across the state after
with crisp nights and cool to mild and mostly clear days. Slight frost risk
through low lying valleys and cold holes on 7th and 8th
mornings. Weak cut off low to develop through Bight area on 11th with some
bands of showers at times, becoming more isolated on 12th as drier conditions
develop as low gets consumed by the high pressure. Conditions beginning to
clear by 13th as new high begins to develop once more from the west.
Potential for another trough system just after mid-month extending from the west.
Rainfall for period 7-12mm generally, decreasing to less than 5mm about
northern ranges. Isolated falls to 20-25mm potentially about the wetter peaks
and exposed windward slopes of southern ranges.
Riverland/Mallee
Cold front due early afternoon for the Mallee and later
afternoon for the Riverland on 5th with band of showers, becoming
more isolated over the Riverland district, especially overnight Isolated
showers to follow with some colder air on 6th briefly scattered in a
stream into SW Mallee/off Lakes and up back side of ranges but conditions
quickly moderating. Isolated small hail possible in the far SW and S of the
Mallee during the afternoon. Cold SW to S winds across the district in wake of
the front. Strong 1036+hPa high moving slowly across the state after with crisp
nights and cool to mild and mostly clear days. Slight frost risk 7th
and 8th mornings and also potentially
the 9th as well. Weak cut off low to develop through Bight area on
11th with some isolated showers developing later and into the 12th though
likely still quite isolated here with drier conditions further inland as low
gets consumed by the high pressure. Conditions largely clearing by 13th
as new high begins to develop once more from the west with a resumption of cold
nights. Potential for another trough system just after mid-month extending from
the west. Rainfall for period 3-5mm generally about the SW Mallee then
decreasing to less than 2-3mm further north and then down to less than 2mm for
the Riverland with the exception of areas closer to the back of the Mt.Lofty
Ranges which may sneak into that stream and thus be closer to 3-4mm. Isolated
falls to 10-12mm in streams off the Lakes and immediate surrounds.
Upper SE
Cold front due mid to late morning on 5th with a general
band of showers, before becoming isolated later. Scattered showers to follow
with some colder air on 6th
but conditions quickly moderating later on
sundown with showers becoming confined to the coastal portion of the district.
Isolated small hail possible during the afternoon. Cold SW to S winds across
the district in wake of the front. Strong 1036+hPa high moving slowly across
the state after with crisp nights and cool to mild and mostly clear days.
Slight frost risk 7th and 8th mornings and also potentially the 9th as well. Weak
cut off low to develop through Bight area on 11th with some isolated showers developing
later and into the 12th though likely still quite isolated here with drier
conditions further inland as low gets consumed by the high pressure. Conditions
largely clearing by 13th as new high begins to develop once more
from the west with a resumption of cold nights. Potential for another trough
system just after mid-month extending from the west. Rainfall for period 5-10mm
generally but decreasing to 2-4mm further north and east. Isolated falls to
10-18mm about the coast.
Lower SE
Cold front due onto the coast by dawn on 5th with a
general band of showers, heavy at times and potentially briefly tending to rain
before becoming isolated later. Scattered showers, some heavy in a cold pool
during the 6th with some small hail likely as well as isolated cold
air thunder with conditions moderating by evening with showers contracting to
the coast. Cold SW to S winds across the district in wake of the front. Strong
1036+hPa high moving slowly across the state after with crisp nights and cool
to mild and mostly clear days. Slight frost risk 7th and 8th
mornings and also potentially the 9th as
well. However low cloud may temper things on the 7th. Weak cut off
low to develop through Bight area on 11th with some isolated showers developing
later and into the 12th though likely still quite isolated here with drier
conditions further inland as low gets consumed by the high pressure. Conditions
largely clearing by 13th as new high begins to develop once more
from the west with a resumption of cold nights. Potential for another trough
system just after mid-month extending from the west. Rainfall for period
15-25mm generally but decreasing to 8-15mm further north and east. Isolated
falls to 30mm about the coast.
Western VIC
Cold front due onto the coast by early morning on 5th
with a general band of showers, more solidified about the SW District and far
more isolated by the Mallee where it should reach by late afternoon in a
weakened state. Scattered showers, some heavy in a cold pool during the 6th
with some small hail likely as well as isolated cold air thunder all about the
SW District and southern portions of the Wimmera with conditions moderating by
evening with showers contracting to the coast. The Mallee will likely only see
isolated showers in the south. Cold SW to S winds across the district in wake
of the front. Strong 1036+hPa high moving slowly across the state after with
crisp nights and cool to mild and mostly clear days. Slight frost risk 7th
and 8th mornings and also potentially
the 9th as well. However low cloud may temper things on the 7th.
Weak cut off low to develop through Bight area on 11th with some isolated
showers developing later and into the 12th though likely still quite isolated
here with drier conditions further inland as low gets consumed by the high
pressure. Conditions largely clearing by 13th as new high begins to
develop once more from the west with a resumption of cold nights. Potential for
another trough system just after mid-month extending from the west. Rainfall
for period 10-20mm generally about the SW District but decreasing to 5-10mm about
the Wimmera and down to less than 5mm for the S Mallee and 1-2mm for the
remainder.
Final Notes:
·
Dry period upon
us with only weak fronts and weak cut off lows to assist in rainfall, the first
due on 5th with cold air on 6th but primarily focused over
the SE Districts.
·
Strong high
pressure to muscle in weakening rain bearing systems as they attempt to move
eastwards
·
Frost risk
increasing from here on in starting May 7th with a slight risk
·
Irregular
systems through winter however fronts when they do occur will still be
vigourous with negative bursts in the SAM (Southern Annular Mode)
·
Goyder's Line
for this growing season will come into play with more difficult conditions
north of it
·
South of
Goyder's line will see better chances of an average to slightly below average
season at least but there will be struggles late season with Positive IOD and
El Nino combination making things tricky
·
Season will not
be as dire as 1994 or 2006 but still broadly below average rainfall for
agricultural areas until at least September
Link to temporary blog website: https://farmweathersa.blogspot.com/
Happy Farming and Cheers from The Weatherman
*Note – For interest only, all thoughts are of The
Weatherman and may not be reproduced without my consent.
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