Widespread rain will continue across the Deep South into mid-week bringing additional relief to the Extreme to Exceptional Drought conditions.
What is triggering the prolonged rain event?
A warm front situated along the Gulf Coast will be the focus for moisture to funnel into the Deep South for the next few days. In addition, several areas of low pressure will move along this front bringing waves of rainfall.
Through Monday evening, widespread 1 to 2 inches of rain is expected from Alabama, Georgia and South Carolina. For Texas, Louisiana and Mississippi broad areas of 2 to 4 inches with areas of higher amounts are forecast.
Through midweek 5 day rainfall totals widespread 2 to ~ 4 inches will be the rule over much of the Deep South.
Will this rain finally break the drought?
While the drought monitor updated on November 29, 2016 still showed broad areas of Extreme to Exceptional Drought conditions, the drought monitor that will be updated on December 6 should show improvement. First, the rain that fell on November 29 was not included in the last drought monitor issuance, even though the update was not available until Thursday Dec 1. One of the limitations of the Drought Monitor is there is a two day delay from when it is updated to when it issued. So any rain that falls from Tues through Thurs morning will not be considered until the following week.
Thus the broad areas of the 1 to nearly 3 inches of rain that occurred on Nov 29th will be included was not included in last week’s update but will be included in the upcoming update.
In addition, the rain that falls between now and Tuesday morning with the current storm will be incorporated into the Drought Monitor for Tuesday, Dec 6.
However even with continued rainfall, the long term rainfall deficits from earlier this summer were 12+ inches in some locations. So it will take additional events to fully eradicate the drought.
Will we see another severe weather outbreak this week?
Thankfully, unlike the event on November 29th, we are not looking at a widespread severe weather risk. While there is a slight risk for severe thunderstorms on Monday, it is expected to remain focused along the Gulf Coast near the front.
Downside of the rain…flooding potential
A concern with the rain is ironically the risk for localized flooding. The intensity of the rain will impact the soils ability to absorb moisture vs. sending the water to creeks, streams and rivers. In areas that see moderate to heavy rain, increased runoff will occur which could cause flooding in creeks and streams. In addition, in more populated areas, flooding may be a problem especially with clogged sewer drains due to leaves and other debris.
Even with the risk of localized flooding the rain is welcomed for many farmers, ranchers and garden enthusiasts especially in Alabama, Georgia, Tennessee and the Western Carolina’s. Even though the growing season is coming to an end, our trees, perennials and cool season crops need the rain in the fall and winter months. In addition the rain will help refill stock ponds and recharge low lake levels.
The team at WxIntegrations will continue to provide relevant information and resources to help you better understand and prepare by incorporating weather impacts into your planning and response.