Tornado rips Shreveport; Typhoon Mirinae deluging the Philippines

Between one and five tornadoes touched down in northwest Louisiana and southwest Arkansas on Thursday. The most damaging tornado hit Shreveport, Louisiana at 5:15 pm EDT, ripping the steeple off of a church and hurling it onto a car. No fatalities were blamed on the tornadoes, though one man was killed when he drove his car into a fallen tree. The cold front responsible for spawning the severe weather will be over Alabama today, where the Storm Prediction Center is forecasting a slight chance of severe thunderstorms. Rainfall amounts from the storm exceeded six inches in many regions (Figure 1), and the cold front draped across the center of the country is responsible for flood warnings for a wide swath, from Texas to Illinois. See our severe weather map or consult our wundermap with the USGS River layer turned on to see where flooding is occurring.


Figure 1. Estimated rainfall from the line of storms that passed through northern Louisiana yesterday and today.

Colorado digs out
The Denver, Colorado area continues to dig out from the biggest October snowstorm to affect the region since 1997. The town of Pinecliff in the mountains just northwest of Denver recorded 46 inches of snow from the storm.

Typhoon Mirinae deluges the Philippines
Category 2 Typhoon Mirinae's deluge has begun over the Philippines' Luzon Islands, as the storm's eye nears the east coast of the island. Mirinae--who's name is taken from the Korean word for "Milky Way"--did not intensify, and now appears to be suffering from land interaction, since the southwest portion of the typhoon's circulation is now over land. The latest infrared satellite loops show no eye, a decrease in the storm's organization, and warming of the cloud tops of Mirinae's eyewall clouds--all indicative of weakening. Satellite estimates of Mirinae's intensity declined a bit over the past twelve hours, and it appears likely that Mirinae will be a Category 1 typhoon with 80 - 90 mph winds at landfall near 18 UTC (2 pm EDT) today. Mirinae's primary threat will be heavy rain, and microwave imagery shows that the typhoon's heaviest rains of one inch per hour lie in the southern eyewall. With the eye expected to track over or slightly south of the capital of Manila, this means that Mirinae's heaviest rains of 8 - 12 inches will fall just south of Manila, with 4 - 8 inches expected over the city (Figure 3). The ground is still flooded and the dams brimming full from the previous two typhoons to hit the Philippines over the past five weeks, so Mirinae will probably cause much heavier damage than is usual for a typhoon of its intensity. Flood water from the September 26 deluge of Typhoon Ketsana is still standing in the streets of some suburban areas of Manila, where more than one million people are living in flooded districts. The combined death tolls from Typhoon Ketsana and Typhoon Parma in the Philippines this year now exceed 1,000, and Mirinae will undoubtedly add to that figure. However, Manila is more prepared for this storm than it was for Typhoon Ketsana, and I am hopeful that the death toll from Mirinae will be far less. Mirinae is expected to emerge over the South China Sea tomorrow and strike south-central Vietnam on Monday. With wind shear expected to steadily increase over the storm, and the typhoon disrupted from its passage over Luzon, it is unlikely that Mirinae would hit Vietnam as anything stronger than a tropical storm with 55 mph winds.

Extreme storm photographers Jim Edds and James Reynolds are in Manila for the arrival of Mirinae, and have posted a video of the surf along the shore from the typhoon at the extremestorms.com website.


Figure 2. MODIS visible satellite image of Typhoon Mirinae at 05 UTC Friday, October 20. A the time, Mirinae was a Category 2 typhoon with 105 mph winds. Image credit: NASA MODIS Rapid Response System.


Figure 3. Rainfall forecast for Typhoon Mirinae for the 24-hour period ending at 06 UTC Saturday October 30, 2009. Mirinae is expected to dump 8 - 12 inches of rain along a narrow swath near its core, passing just south of the capital of Manila. Image credit: NOAA/NESDIS.

Quiet in the Atlantic
There are no threat areas in the Atlantic to discuss, and the the Caribbean is dominated by dry air and high wind shear. A non-tropical low pressure system in the middle Atlantic Ocean, near 32N 50W, is cutting off from the jet stream and will slowly wander westward toward Bermuda over the next 3 - 4 days. It is possibly that the low will spend enough time over water to acquire some tropical characteristics and become Subtropical Storm Ida. The storm could bring high winds to Bermuda on Monday. Elsewhere in the Atlantic, none of the computer models is calling for tropical storm development over the next seven days. Most of the models are calling for a tropical storm to form off the Pacific coast of Mexico near the Guatemala border by the middle of next week.

Jeff Masters