FRIDAY EVENING WEATHER - A FAIRLY QUIET WEEKEND FOR MANY AND WARM. NEXT WEEK THE WEATHER MAY TURN.

The weather certainly more stable than in previous weeks, the weekend looking pretty good for many areas with the sunshine back in full force away from the east coast and northern tropics. Temperatures likely to be above average for a while yet with a decent northwest to westerly breeze bringing the warmer air from WA into SA and then shifting that into the southeast and eastern states through the weekend and into next week.


Rainfall looking relatively lean this weekend for most, the showers on the east coast of QLD mainly light to moderate, but heavier falls will be found with the trough lingering over Cape York and then being fed by the trade winds out of the east with some locations set to see 100-200mm this weekend.


Northern tropics, very much routine weather as we wait for the MJO to rotate around and trough the northwest and west. We will see showers and thunderstorms most afternoons and some of those could be gusty with damaging winds possible, we have seen that most days this week through northern WA and the Top End.


Out west, a weak front clipping the southwest tonight and again on Sunday, may bring in some moisture from the Indian Ocean and this may allow for patchy falls, but more likely with the second front overnight Saturday into Sunday. Timing is everything at the moment with the moisture plumes being picked up by the cold fronts as the race to the south of WA. The seasonal shift is rumbling in the next few weeks perhaps, and seeing frontal weather on the charts again is a sign of turning towards this.


Overall the nation looking relatively dry for much of next week, but I would be watching very closely the development of that moisture running through the mid and upper levels and whether that can be drawn into a trough over the eastern inland of QLD, NSW or VIC bringing up rainfall chances as another front races through southeast Australia. The ingredients are there for more widespread rainfall to form in that region, but as I mention the low confidence in forecasting does continue.


Lets take a look

FORECAST

Rainfall Next 10 Days

Rainfall is forecast to remain very much of low confidence away from the tropics. There are a few areas to watch in the coming days. The moisture running over the nation in the upper levels being drawn into a trough over the southeast or eastern inland mid to late next week which could spawn patchy falls through SA but higher rainfall rates over VIC, NSW or QLD. We have to factor in the positive SAM phase building next week and that could see rainfall chances coming up over the eastern states. The tropics, watching the approach and passage of the MJO over northern areas, do we see enhanced rainfall connected to the formation of tropical lows/cyclones through the region. We have to watch that very closely because we may see increased rainfall for inland areas of the nation and this could spread to all parts of the nation. Flooding may also develop over northern Australia during the coming fortnight as well. Finally, all of that moisture over the northwest could help to form a large scale weather system spreading through the nation. There have been some indications of a large scale trough spreading through the nation from the end of next weekend and then into the medium term coming through SA and into VIC/NSW and QLD with heavy rainfall potential. These ideas will be ironed out and organised in the next few days and we should have a better idea of where things are going from Sunday afternoon if not Monday.

REVIEW OF THE CLIMATE DRIVERS.

SOUTHERN ANNULAR MODE - SOUTHERN OCEAN - TURNING POSITIVE FOR A PERIOD - THE SECOND NEUTRAL PHASE IS THE ONE TO WATCH.

The volatility of the SAM is certainly being seen in the rainfall and temperature spread across the southern parts of the nation and also in relation to the fast flow westerly wind belt to the south of the country. So we saw the bottom of the negative phase yesterday but it was recorded at about 1-1.5 units closer to neutral than what was forecast. So this will mean that the frontal weather (we can see it at the moment) will remain further south, ridging will stay over the southern parts of the nation and the easterly winds will likely sink south from QLD with the SAM tending positive again. Now the positive phase next week looks to be strengthening and the models as mentioned in the video are starting to pick up on, placing heavier rainfall in the east of the nation as a result. But the SAM being so volatile at the moment means the forecast is poor.

MJO - TROPICS - MOVING INTO PHASE IN THE NEXT FORTNIGHT.

Seeing for the first time that the MJO is sweeping through from the Indian Ocean, over the Top End and then into the Western Pacific at pace which is the first time this particular model has shown this. That would see moisture rotate fairly quickly through the NT and into QLD. But when the MJO is in the Western Pacific, rainfall can increase quite dramatically for the NT and QLD and then run over the interior parts of QLD and through the eastern NT into northern NSW. So will watch that trend.

STORM OUTLOOK - INTO NEXT WEEK

Thunderstorm Forecast Saturday

Thunderstorms will appear mainly through northern parts of the nation, and be found across the tropics where storms could be gusty during the afternoon. I have removed the threat of thunderstorms over the south and east with drier air and heights coming up throughout the atmosphere. There may be a few showers about and a rumble of thunder but overall not worth printing out a threat area for now.

Thunderstorm Forecast Sunday

Thunderstorms are forecast to develop further south over WA being drawn southwards by another wave of low pressure south of the state. Thunderstorms unlikely to be severe at this time. Thunderstorms scattered to numerous over the northern tropics with storms gusty at times with damaging winds a low risk. A cluster of thundery showers over the outback of QLD, again not likely to be severe.

Thunderstorm Forecast Monday

Thunderstorm activity fairly similar to Sunday with the coverage still remaining mainly over inland areas of WA along and to the east of a trough extending from the tropics southwards to the central interior, possibly northern areas of the SWLD and into the Goldfields and Wheatbelt. There may be some strong to severe storms over the northern tropics with gusty winds and heavy rainfall leading to flash flooding. There may be a few thundery showers about the Carnarvon Ranges in QLD and possibly extending back to the southwest into the eastern Channel Country. Settled elsewhere with ridging.

Thunderstorm Forecast Tuesday

Thunderstorms once again continuing through inland areas of WA through a similar spread to Monday with the coverage expanding over the tropics with the approach of the MJO. Thunderstorms could be gusty with damaging squalls over outback WA and over the tropical northwest. Heavy rainfall may lead to pockets of flash flooding over the north and northeast tropics.

Thunderstorm Forecast Wednesday

Thunderstorms may contract a little further north through WA as the next high ridges through the southern districts, lifting the trough northwards. There may be extensive showers and thunderstorms over the northern tropics with the MJO sitting very close to the region with severe weather possible. In the east, a wave forming on the north of a front passing over VIC and NSW could lead to a few thunderstorms amongst increasing showers on and east of the Great Dividing Range later in the day.

DATA - Refer to the video for further information and it is critical to keep check of the data sets to understand where the next major weather events are emerging from outside of this period. It may be quiet now but I am all about preparation and ensuring that information is shared with you as soon as it is available.


00Z GFS - Surface Pressure Pattern and Rainfall Distribution - Next 2 Weeks

I have more analysis in the video at the top of the page, but once again the confidence is still low, and likely to remain low for the next 48hrs. However the idea of a major weather event sweeping the nation in the medium term is still on the data sets this evening and that I will not ignore at this time but it is just outside of the forecast period of greater confidence, the short term. So just keep watching but don't react just yet. More to come on that through the weekend. The weather in the short term mostly settled, we have got an active tropical airmass over the north, some of that moisture may sweep south and southeast through the nation as we track into later next week, that may get caught up in a trough over the eastern inland of NSW and QLD. We have a positive SAM developing next week so showers are likely to increase at some stage next week for the coast (whether that moves inland as well is up in the air) but there certainly is a shift back towards easterly winds returning. So will watch that closely. Otherwise watching the MJO quite closely over the next week for tropical cyclone/low development. These late season cyclones which I have spoken about here, can bring about some large scale rainfall events.

00Z GFS - Precipitable Water Values - Next 2 Weeks

Moisture is easing in it's depth over the southeast and south of the country for the week ahead, we have had another very humid spell, but I think next week will feel much more seasonal and warmer with a drier airmass. Over eastern NSW through to much of eastern QLD into the tropics, the humidity will remain high with warm temperatures so more late season sticky conditions, likely above average thresholds over the NT and FNQ. Into the west, dry air for the most part over the inland but there are short bursts of moisture surging through the SWLD and southern areas with the northern most aspects of frontal weather dragging in the moisture from the approaching MJO over the Indian Ocean. This may peak in the medium term with a large scale trough passing through the very moist air leading to widespread rainfall and higher moisture sweeping through from west to east impacting large areas of the nation. Is it the Autumn Break? We will have to wait and see.

00Z GFS - Rainfall Accumulation - Next 10 Days

Also refer here to see the previous day of rainfall output from the GFS to show you the low confidence forecasting in the next 2 weeks.

Refer to the video for more context and analysis

00Z CMC - Rainfall Accumulation - Next 10 Days

Refer to the video for more context and analysis

00Z GFS - Rainfall Accumulation - Next 2 Weeks

Refer to the video for more context and analysis

More coming up on Saturday with another glimpse at the short and medium term, trying to see where the guidance takes us for the end of the month into April, there have been some major weather systems being shown on the charts in recent days and that will continue but once again, forecast confidence remains low. Have a great start to your weekend.

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