PDC Weekly Global Flood Survey: February 2, 2012
According to the latest NASA prediction, the current La Nina episode is peaking. This is the second consecutive year that the Jason altimetric satellites have measured lower than normal sea surface heights in the equatorial Pacific, and unusually high sea surface heights in the western Pacific. La Nina conditions change global weather patterns, and are associated with less moisture in the air over cooler ocean waters. This results in less rain along the coasts of North and South America, and along the equator and more rain in the far Western Pacific. (See Figure 1)
Precipitation & Flooding: Pacific
Focusing our attention on the Pacific, we can see an extensive swath of precipitation extending from the southwest to the northeast across the northern latitudes of the Pacific. (see Figure 2) The bulk of this rainfall runs along the main storm track of the mid-latitudes, generally under the polar jet stream between 30 and 50 degrees north latitude. The Hawaiian Islands remained south of this rainfall, continuing their dry winter pattern.
In the southern Pacific, there was a much thinner swath of rainfall that moved in a west to east direction offshore from Asia. This precipitation was associated with the inter-tropical convergence zone, where the northeast and southeast trades meet near the equator. This area was well south in latitude from the Hawaiian Islands.
A third, and by far the heaviest swath of precipitation in the Pacific extended from the Solomon Sea, into the Solomon Islands, then southeast into Vanuatu towards Fiji. Over the last week the southern Pacific was extremely wet from American Samoa, down through Tonga and as far east as the Pitcairn Islands before impacting the coast of South America.
Flooding in Fiji: According to UNOCHA, torrential rains occurring over the western region of Viti Levu, Fiji’s largest island, in late January has resulted in severe flooding and the displacement of thousands of people. Current situation reports indicate thousands of people are impacted with 6 people reported dead, 3 injured, and 841 currently in Evacuation Centers. Estimated losses as a result of the flooding are exceeding $20 million US dollars.
Precipitation & Flooding: Americas
Following the precipitation out of the Pacific into the Americas (see Figure 3) it impacts the coasts of Oregon and Washington. As various storm systems moved across the Rocky Mountains it became scattered across the northern states moving eastward. The eastern United States picked up considerable rainfall from a swath generated from the Gulf of Mexico. The precipitation moved northeast from the Gulf across Louisiana, Alabama, Tennessee, and ultimately into eastern Canada.
Currently, South America received moderately heavy rainfall from just south of Columbia down into the Amazon. Brazil southward through Paraguay and eastward, also experienced locally heavy rainfall. The area around Guyana and French Guiana was locally very wet, with rainfall extending eastward well out into the Atlantic towards Africa.
Flooding in Argentina: According to RSOE Emergency and Disaster Information Service (EDIS), a severe storm was reported to have impacted the city of Cordoba, Argentina, on January 31 resulting in severe hail and flooding. Strong winds generated by the storm have been reported to have destroyed roofs. Latest reports indicate that 300 people were evacuated, 2 are reported dead, and 15 have been reported injured.
Precipitation & Flooding: Africa
The PDC Global Hazards Atlas shows a large area of precipitation extending through southern Africa and eastward into the Indian Ocean (see Figure 4). Precipitation has been locally heavy at times. Mozambique continues to experience flooding with ongoing rainfall delaying response and recovery efforts.
Flooding in Mozambique: NOAA Climate Prediction Center reports indicate that subsequent tropical cyclonic activity, Dando followed by Funso, in the Mozambique Channel have produced persistent torrential rainfall, resulting in severe widespread flooding across Malawi, Mozambique, and Madagascar in late January. Above average rainfall is predicted to persist across northern and southern Mozambique, between February 2 and February 8, potentially worsening ground conditions which are already saturated from weeks of rain. Integrated Regional Information Networks (IRIN) reports indicate 40 deaths and 116,333 people (approx. 51,670 as a result of Dando and 64,663 as a result of Funso) were affected by the flooding.
Over the next week PDC will be monitoring areas of high precipitation and keeping a close eye on flooding across the globe. Currently PDC is monitoring significant flood events in the following areas: Australia, Fiji, Guyana, Indonesia, Malaysia, Mozambique, and the Philippines.
For the most up-to-date information on these flood events and all-hazards, download the free PDC Disaster Alert mobile app for iOS and Android devices.