Wednesday, October 17, 2007

Severe Weather Risk Elevated This Afternoon And Tonight


11:30 AM Update...THE ENTIRE STATE IS UNDER A MODERATE RISK THIS AFTERNOON AND TONIGHT. TORNADO WATCHES ALREADY BEING ISSUED. STAY WITH CHANNEL 7 FOR THE LATEST INFORMATION.

The Storm Prediction Center in Norman, Oklahoma has issued a moderate risk for severe weather for the northern 2/3 of Arkansas. Do you ever wonder what a slight, moderate, and high risk actually means? The text below is directly from the Storm Prediction Center. The text in red applies to the situation we are in today. While there will be a few isolated showers and storms this morning, the best chance comes this afternoon and this evening. The front sweeps through Thursday with windy conditions.

Three risk categories (SLGT, MDT, and HIGH) are used to symbolize the coverage and intensity of the expected severe weather threat. A SLGT risk implies well-organized severe thunderstorms are expected, but in small numbers and/or low coverage. Depending on the size of the area, approximately 5-25 reports of ¾ inch of larger hail, and/or 5-25 wind events, and/or 1-5 tornadoes would be possible. A MDT risk indicates a potential for a greater concentration of severe thunderstorms than the slight risk, and in most situations, greater magnitude of the severe weather. A HIGH risk area suggests a major severe weather outbreak is expected, with a high concentration of severe weather reports and an enhanced likelihood of extreme severe (i.e., violent tornadoes or very damaging convective wind events occurring across a large area). In a high risk, the potential exists for 20 or more tornadoes, some possibly F2 or stronger, or an extreme derecho potentially causing widespread wind damage and higher end wind gusts (80+ mph) that may result in structural damage. A SEE TEXT label will be used for areas where a 5% probability of severe is forecast, but the coverage or intensity is not expected to be sufficient for a slight risk.

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