MONDAY MORNING WEATHER - THE HEAVY INTERIOR RAINFALL CONTINUES - SEVERE STORMS OUT EAST.

But the drier air is not too far away with a pattern flip seeing a front propelled through the nation's southeast, new high pressure ridging further north for a spell, these items on the board combining to bring about the chance to dry out and a return to seasonal conditions throughout the southern half of the nation.


Over the inland areas north of about Coober Pedy, we have a lot of rainfall on the board through the coming days related to a tropical low which is sending rainfall rates to near record levels. Flooding has been widespread and continues to be a cause for concern in the coming days with a tropical low meandering about.


Now whether this system turns south or west will have major implications on the rainfall, temperature and humidity forecasts in the medium term and as spoken about last night, the overall confidence in the forecast is low.


For the east coast, the blocking pattern that has been in the Tasman Sea for some time continues to offer the chance of showers increasing and cooler weather, with some modelling suggesting heavy rainfall may be back on the cards, so that is something to watch for NSW and QLD.


Across the tropics, severe weather is expected to continue until mid week before we see the monsoonal flow settle down with rain and thunderstorms also easing a tad.


Signals for tropical cyclone activity to increase in the medium term does exist but there is little skill picking where will see that happen and when, but just be aware of that risk moving forward. This too will likely set up a wet end to the month for much of the nation.


Lets take a look



FORECAST

Rainfall Next 10 Days

Not a whole lot of change from last night, we still have about 2-3 days of high humidity and anomalous rainfall expectations across the north, central and eastern areas of the nation so the uneven distribution of rainfall will continue for the inland areas over the east, but more widespread falls are expected over central, northern and northwest areas of the nation thanks to the monsoon trough and a tropical low. Once again, the confidence remains low on two feature. The first being the tropical low over the northwest, where does that feature go? The models split on the idea of it heading west or south, so that will have large implications on the rainfall spread over inland areas and through the west mid to late week. The second feature, the trough on the east coast and that forming in combination with the onshore winds. That may lead to widespread rainfall developing on the east coast but some modelling supports the peak of the heavier rainfall being offshore but some bring it onshore over the NSW and QLD coasts. Overall the weather is looking a lot drier from mid to late week with cooler drier air surging through the south and southeast. So the tropics will be gone very soon.

Thunderstorm Forecast Monday

Thunderstorms remain a high risk over a broad area on Monday. Severe thunderstorms are most likely over northwest SA into the eastern parts of WA and much of the NT with a deep moisture profile, multiple troughs and a tropical low all combining to produce heavy rainfall and dangerous flash flooding. There will be high humidity back over the south and southeast with scattered afternoon storms with the chance of heavy rainfall once again away from the coast. The drier air and more stable air over the east of QLD is thanks to a ridge.

Thunderstorm Forecast Tuesday

Thunderstorms are likely to continue on and east of a trough through SA, VIC and into the ACT and NSW. Storms have a high chance of producing heavy rainfall leading to flash flooding and damaging winds. For northern areas of the nation, through the central NT and into QLD, heavy rainfall leading to flash flooding is a very high risk with thunderstorms. A monsoonal low over northwest WA will begin to move southeast and take the severe weather risks through central areas of the state and possibly into the far north of SA. Thunderstorms over the Top End and Cape York may be gusty with damaging winds.

Thunderstorm Forecast Wednesday

A flush of dry air over southern areas of the nation will see the storm risk contract north and east out of the southern states with high pressure ridging in. Thunderstorms on and north/east of a trough through NSW, SA and WA will lead to widespread showers and thunderstorms, some severe with heavy rainfall and flash flooding the main concern. The monsoon trough will continue to trigger squally showers and storms over the northern tropics with the possibility of damaging wind gusts.

Tropical Depression Watch This Week

A deepening tropical low within the monsoon trough is likely to lead to heavy rainfall and squally winds to emerge through the areas identified in yellow. Heavy rainfall will spread west through much of northern WA with a flood risk. On the northern flank of the low, a strengthening westerly flow may see showers and storms increase for the northern Top End.

DATA - Refer to video for more information to cross check against the Euro with the GFS.


12Z Euro - Surface Pressure Pattern and Rainfall Distribution - Next 10 Days

The Euro places the tropical feature in the northwest and keeps it up there rather than forcing it south and southwest like the GFS. This means the downstream impacts are different to the CMC and the GFS as well as other models. That means overall, the forecast confidence for the northwest, central and eastern parts of the nation remains lower in terms of how much you will see rainfall wise. The higher confidence does exist with the cooler and drier flush of air moving through the south and southeast through the period leading to a more comfortable end to the week with below average temperatures and drier weather as well.

12Z Euro - Precipitable Water Values - Next 10 Days

The precipitable water values are still extremely high over large chunks of the country with very humid air leading to that tropical feel and the uneven distribution of rainfall within this airmass. But it gets knocked out of the southeast and south during this week and by the end of the week, cooler than average weather for the southeast with onshore southerly winds and a drier airmass. The drier air will then flush through much of the nation, leading to less rainfall chances into the second week of February for most of the inland. Onshore winds in the east and the monsoon over the north, keeping the humidity levels very high in these regions with rainfall chances also remaining high. But the forecast confidence is relatively low for later this week into the weekend related to these areas as explained.

12Z Euro - Rainfall Accumulation - Next 10 Days

Refer to video for more information

12Z CMC- Rainfall Accumulation - Next 10 Days

Refer to video for more information

12Z GFS - Rainfall Accumulation - Next 10 Days

Refer to video for more information

12Z Euro - Rainfall Accumulation - Next 15 Days

Refer to video for more information

12Z GFS- Rainfall Accumulation - Next 16 Days

Refer to video for more information

More weather information coming your way a little later on this afternoon, I am on a travel schedule smack bang under the severe weather through the NT, which is helping me forecast down stream impacts for you in the south and east. More this afternoon.