Nora Intensifying Quickly as it Approaches Northern Queensland!

 

Severe tropical cyclone Nora has intensified to Category Three status over the warm waters of the Gulf of Carpentaria. Nora is compact so conditions remain relatively tranquil along the coast as of late Saturday morning. However, conditions will deteriorate quickly later Saturday afternoon into the overnight, especially from Aurukun south. Nora is expected to turn south near the western coast of the Yorke Peninsula and slow down, possibly even stalling over the southeastern Gulf or the adjacent coast for a day or so!

 

 

The heaviest impacts will fall on the coast from Aurukun down to Carpentaria. In this region, winds could gust up to 200 kph or more, leading to severe structural damage and widespread power outages. Rainfall up to 500 mm will also occur, leading to flash flooding. A moderate storm surge will affect the immediate coast, exacerbating any flooding issues.

Nora or its remnants will be slow to exit the region. Later next week, the circulation could move westward across NT and WA, producing locally heavy rain and gusty winds. We’ll have additional updates in the coming days!

Topsy-Turvy March Weather Courtesy of Unusual Atlantic Pressure Pattern

Through the month of February, residents of the Northeast could afford to chuckle at the “six more weeks of winter” promised by the fabled groundhog. Many cities reported among their warmest Februarys ever with clear days and little snowfall.

Then March hit. In the last 3-4 weeks there have been no less than four major Nor’Easter storms, bringing record snowfall and frigid temperatures. The table shows average temperatures for the major cities – note that March so far has been two to three degrees colder than February (all temperatures in deg Fahrenheit). Other areas of the globe have seen anomalous weather as well, from bone-chilling cold and snow in Europe to record warmth in the Arctic Circle.

 

 

 

One major factor that could help explain the topsy-turvy weather pattern is a particular phase of the North Atlantic oscillation, or NAO. The NAO is a fluctuation in surface pressure patterns over the Atlantic ocean. During much of February the NAO was in its positive phase (see graphic below), a situation that usually results in quiet, mild weather. However, from late February into early March the NAO plunged into deeply negative territory. In the negative phase of the NAO, the upper level jet stream that moves storms and air masses around becomes highly amplified. Warm air from the tropics can rush north into the Arctic, displacing frigid air down to the south over eastern North America or Europe. This turbulent pattern promotes more frequent development of winter storms over the U.S. Eastern seaboard and western Europe.

 

 

The NAO is currently forecast to trend a bit more towards the neutral phase. That combined with lengthening daylight hours should finally bring winter to a close in the next few weeks. But those that were fooled by the mild February have learned their lesson.

 

 

Major Gulf of Carpentaria Cyclone Nora This Weekend!

Tropical Cyclone Nora is gaining strength over the Arafura Sea (see satellite image above, courtesy of Australia’s Bureau of Meteorology). Winds and rains are already increasing over Marchinbar Island. Model guidance indicates the cyclone will turn southeast into the very warm waters of the Gulf of Carpentaria. It’s a favorable environment for intensification and interests all along the Gulf coast should pay close attention!

Nora will likely be a small but severe cyclone as it approaches Mornington Island or the adjacent mainland late Sunday or Monday. The heaviest impacts will fall on this region, including northern QLD and northeastern NT. Destructive wind gusts of 200 mph are possible along with torrential rains up to 500 mm (see graphics below)! A moderate storm surge could exacerbate flooding issues in this area. We’ll continue to monitor this dangerous situation and issue further updates in the coming days.

 

 

Nor’easter #4 Targets East Coast

The fourth nor’easter this month will target the Mid-Atlantic and Northeast through Wednesday. Rain, sleet, snow, and wind will accompany the storm from the Ohio Valley to Virginia up to Maine.

Tuesday Recap

An initial burst of precipitation on during the day Tuesday brought accumulating snow to portions of Virginia, Maryland, and Pennsylvania.

The Maryland Department of Transportation spent Tuesday treating roadways.

Wednesday Forecast

Rain, sleet, and snow will spread across NYC and southern New England by Wednesday morning. As low pressure strengthens off shore, colder air will be drawn into the storm causing the rain-snow line to sink toward the coast. Precipitation will continue, heavy at times, in southern and eastern New England through Wednesday night.

A nor’easter will bring a wintry mix of precipitation to the Northeast Tuesday and Wednesday.

In addition to the precipitation, strong winds and minor to moderate coastal flooding are expected. The combination of snow, sleet, and wind will make for difficult driving conditions on Wednesday from Virginia to eastern New England. Air travel will also be impacted, with numerous delays and cancellations likely.

The nor’easter will move away from the region on Thursday.