Saturday, February 26, 2011

Another Round of Storms 2/26

Meteorologists are keeping their eyes on a storm system that could bring another round of severe weather to southeast Missouri, southern Illinois, western Kentucky, northwest Tennessee and northeast Arkansas.

The upper-level portion of the storm of interest is located over western California this morning. You can see the storm by looking at a satellite loop at this link.

All models are bring the storm off the west coast and moving it over the Midwest late Sunday night and early Monday.

The good news/bad news about the storm is that it will be coming during the overnight hours and during the morning hours. That is good as we won't have the heating of the day to help intensify storms. However, this system looks to have a large amount of support in the upper-levels and with the wind field, along with moderate instability, storms will still be able to thrive.

It is bad because most people will be sleeping as it moves through. Injuries and death statistics rapidly increase when storms move through areas during the overnight hours.

The Storm Prediction Center has the entire KFVS viewing area included in a "Slight Risk" area in their latest Day 2 Outlook.

Places included in the "Slight Risk" area include Tulsa, Springfield (IL and MO), Indianapolis, Nashville, Louisville, Memphis and Little Rock.

The above outlook covers the time period from 6am Sunday through 6am Monday.

Another product from the Storm Prediction Center at the Day 2 level is the probabilities of severe weather.

The probability forecast is generated by forecasters at the Storm Prediction Center. The areas indicate the probability of any type of severe weather (wind, hail, tornado) occurring within 25 miles of any point. The blue hatched area indicates a 10% chance of significant severe weather occurring within 25 miles of a point.

I took a look at some of the new computer model data from this morning. There is considerable support for severe weather in the upper-levels of the atmosphere.

Models are showing a lot of divergence taking place in the upper-levels in south/southeast Missouri starting around 9pm CT Sunday night. The diverging air allows air to rise. Models are also showing the nose of the strongest part of the jet stream, a jet streak, will be pushing in to the area Monday morning.

Instability is there. It isn't high like you see in spring and summer, but for February, it is plenty high enough to spark thunderstorms.

Right now, my feeling is that we could see two rounds of storms in the KFVS viewing area. The first occurring late Sunday night (8pm Sunday - 2am Monday). This time period could spark individual storms. The second time period would be from 5am Monday through 10am Monday as a line of thunderstorms moves through.

Damaging wind should be the main threat from the storms. However, a couple of tornadoes could spin up with the wind environment.

A new SPC Day 2 Outlook should be out within the next hour. I wouldn't be surprised to see the SPC upgrade parts of the area to a Moderate Risk sometime between now and tomorrow morning. I'll try to get an update published this afternoon.

Just a reminder... Since we are talking about overnight storms, make sure you have a way to be alerted to severe weather warnings so you and your family can take action. A great way to be alerted in the middle of the night is to have a NOAA weather radio. I HIGHLY suggest having one. I believe they are just as important as smoke detectors. Every house and every business should have one.

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