A very pronounced wedge of drier air has extended itself into central Alabama this morning associated with a surface high pressure system that is off to our east. As time progresses and the high continues to move further away from our region, this area of drier air is expected to weaken. At the same time, a surface low pressure system (currently located in the southern parts of the central plains) will begin to strengthen and move east towards Alabama. Along with the arrival of this low, we should also see an increased chance of rain showers and storms. Starting late Saturday night and into the early hours of the day on Sunday, a significant air mass change will occur in our atmosphere ahead of any showers or storms. After midnight, the chance of showers and thunderstorms will begin to become more widespread in nature. This is only the start of what we could possibly see tomorrow, but there are many factors we have to consider first…
The threat for severe storms tomorrow hinges on the placement of a warm front. First, we do not currently know how far north into central Alabama the warm front (associated with the previously mentioned low pressure system) will go. The low will drag the warm front northeastward across the state of Alabama during the day as it tracks through the state. If it travels far enough into the state, then we will have the instability in the atmosphere needed for severe weather development. As the warm, moist air from the gulf advances northward behind the front, the severe weather threat will increase - especially along the warm front. Severe thunderstorms with damaging winds and the potential for a few isolated tornadoes will be the main threat for the day on Sunday.
Since our earlier update, the Storm Prediction Center (SPC) has slightly adjusted the convective outlook for our viewing area.
From now until 6AM on Sunday morning:
From Sunday at 6AM until 6AM on Monday:
The SPC has a slight risk coverage over our area for. The area that is shaded in yellow means there is a slight risk for severe storms … when SPC says “slight risk,” they put a number value 15%. Therefore, the SPC is currently saying there is a 15% chance that any storms we see in the shaded yellow area could turn severe. This slight risk area currently includes our entire viewing area. The main time line for the severe weather threat appears to be from as early as 7AM to 4PM in the afternoon… within that broad range, it appears the strongest threat will probably be from about 10AM to 2PM, as daytime heating adds fuel to the fire. The strongest of the storms will be capable of producing damaging winds and or isolated tornadoes. Besides the threat for severe weather, rainfall could be rather excessive… anywhere from 1”-2” in expected for most of Alabama, with even higher isolated values.
What can I do to be ready? With some uncertainty still on the strength of this event, here is what you can do to be prepared:
- Weather radio: make sure you have fresh batteries in your radio and it is turned on with the volume up.
- Check back in with updates: you can download the WSFA Weather App for your smart phone and tablet. This allows you to turn on push notifications that will automatically alert you if a warning or watch were issued. Also, you can text your county name to 41212 to receive text notifications for watches and warnings for your county.
- Have a safety plan: know where you and your family would go if there was a warning for your area.
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Amanda Curran, Doppler 12 StormVision Meteorologist
Facebook: Amanda Curran WSFA