Flooding Rainfall Imminent for Northern Argentina!

 

A stationary front is hung up from northern Argentina to the Brazil-Uruguay border region. Atlantic moisture will be drawn into this area, leading to persistent storms in the mid to late week time frame. New torrential rainfall on top of already saturated soil will lead to serious flash flooding.

 

 

Northern Argentina and Uruguay have been in a rainy pattern for months. Rainfall has been three to five times normal values so far this summer (see map above). This heavy rainfall has significantly disrupted soy bean farming in this fertile region. Unfortunately, another round of torrential rainfall is on the way.

Model guidance suggests that 300-450 mm (12-18 inches) of rain could fall over northeast Argentina, especially the province of Corrientes, leading to major flooding. Rainfall of 150-300 mm (6-12 inches) will encompass a larger area of northern Argentina and areas near the Uruguay-Brazil border. The heaviest rainfall will fall from late Wednesday into early Thursday. By Thursday night into Friday morning, rains will be diminishing across this region. However, runoff could cause significant rises in the Paraná river system into next week.

 

Severe Storms To Hammer Sydney Metro Later Saturday!

A significant upper level system is sprinting eastward across southeast Australia today. It will spark the hot, humid air already in place across much of New South Wales to produce dangerous thunderstorms this afternoon and evening. These storms will develop first in the early to mid-afternoon from the interior down through the capital district. They’ll threaten Sydney after around 5-6 pm. The strongest cells will bring large hail up to 5 cm in diameter, damaging wind gusts of 80-110 kph, and locally flooding rainfall! The energy for this severe outbreak will wane in the late evening hours as the storms approach Newcastle, causing them to diminish.

Dual Cyclones Threaten the South Pacific Tropical Basin!

 

We’re approaching the middle of summer in the Southern Hemisphere and the tropics are starting to heat up. Cyclone Penny has redeveloped over the central Coral Sea after dropping torrential rain over northeastern Australia around New Year’s. Meanwhile, the ninth cyclone of the season (unnamed) has spun up over the South Pacific. Both of these storms could bring significant hazards to portions of the region in the next several days.

 

 

Cyclone Penny first developed over the extremely warm waters of the Gulf of Carpentaria in northern Australia on New Year’s Eve. The cyclone was originally part of an active monsoonal flow enhanced by an upper level trough. This combination of factors has been dumping flooding rains over northern Queensland for the past few weeks. Penny also produced localized wind gusts to 90 kph. It weakened to a tropical low as it crossed the peninsula through 1-2 January, however it has regained strength over the open, warm waters of the Coral Sea. Penny will likely turn south and southwest over the next several days. By late this weekend or early next week, the cyclone could be threatening another landfall in coastal Queensland (see map below). Conditions don’t favor rapid, sustained intensification, however gusty winds and very heavy rainfall are likely threats wherever the cyclone moves.

 

 

Cyclone Nine developed overnight north of Fiji (see map below). Warm water and a favorable upper level wind pattern support continued intensification as the system moves south. The Fijian archipelago will likely see stormy weather this weekend, including high winds and heavy rains. The system will weaken as it moves south away from the islands next week. Lead photo courtesy Wikipedia contributor Firth McEachern.

 

Oppressive Heat Wave Heralds the New Year Down Under

 

Much of Australia is baking under a stubborn ridge of high pressure as the calendar turns to 2019. High temperatures will continue to reach well up into the 40s over the interior, not uncommon for the middle of summer. However, this heat will creep into the major coastal cities as well in the next few days, creating a dangerous heat stroke risk for the dense urban population centers.

 

 

Hot, dry air will invade much of Victoria on Friday, including the Melbourne metro area (see map above). Northerly winds off the interior deserts will push temperatures above 40 degrees in the city. These will likely be the warmest temperatures there since January 2018. In fact, Melbourne averages only about one day above 40 degrees all year. Fortunately, this extreme heat won’t overstay its welcome. By this weekend, look for highs near normal in the 20s around Melbourne thanks to onshore winds.

 

 

Much above average temperatures are dominating New South Wales, as well. The map above shows the potential for an official heatwave (extreme temperatures for three consecutive days) to end the week. Melbourne is excluded from the higher categories only because the dangerous heat there will be limited to Friday. The capital of Canberra has seen high temperatures above 30 degrees for the past nine days. Little relief is expected in the next several days, potentially not until early next week. The capital hasn’t seen a streak of 13 days above 30 degrees since January 2017. Sydney will see hot temps, too, especially on Saturday when highs will reach the mid-30s. Lead photo courtesy flickr contributor Alex Proimos.