Latest Mesoscale Precipitation Discussion From The WPC

| November 30, 2019 @ 9:55 pm

SUMMARY: Bands of heavy showers and thunderstorms will continue to foster concerns for areal flooding and some flash flooding going through the overnight hours.

DISCUSSION: The latest radar imagery shows an expansive area of heavy showers and thunderstorms impacting areas of central/northeast MS, northern AL, and south-central TN. The convection is focusing along and ahead of a cold front approaching the TN Valley and is associated with a deep layer trough advancing east across the Midwest.

Much of the convection is embedded within highly diffluent flow aloft and is coincident with a southwest low-level jet of 40 to 50 kts. The low-level jet is enhancing moisture transport up from the central Gulf Coast region, with PWs of 1.6 to 1.8 inches and this coupled with a nose of 500 to 1000 j/kg of MUCAPE is leading to relatively efficient bands of showers and thunderstorms. Some rainfall rates have occasionally been upwards of 1 to 1.5 inches/hr, and this coupled with a tendency for some repeating cell activity over the same area has already led to areas of flash flooding.

Additional heavy rainfall is expected to impact areas of northeast MS, northern AL, central/southern TN, and at least clipping areas of far northwest GA going through the overnight hours as the upstream cold front gradually approaches. The instability parameters will tend to wane somewhat, but there should still be sufficient large scale forcing and moisture transport for locally enhanced rainfall rates.

Expect as much as an additional 2 to 3 inches of rain going through 3:00 am, and this will likely result in at least a likelihood of some areal flooding, but where the rainfall rates exceed 1 inch/hr, some flash flooding can be expected as well. This will especially be the case across areas of northern AL where some flash flooding is already ongoing.

Category: Alabama's Weather, ALL POSTS, Severe Weather

About the Author ()

Scott Martin is an operational meteorologist, professional graphic artist, musician, husband, and father. Not only is Scott a member of the National Weather Association, but he is also the Central Alabama Chapter of the NWA president. Scott is also the co-founder of Racecast Weather, which provides forecasts for many racing series across the USA. He also supplies forecasts for the BassMaster Elite Series events including the BassMaster Classic.

Comments are closed.