Wednesday evening severe weather update: overnight and Thursday

The Memphis metro is under a Tornado Watch until 3am. Though the tornado threat in the immediate metro is low, it is not zero, as storms that move into the region will encounter a very dynamic wind environment with strong low level wind blowing at highway speeds and a favorable upper level jet stream that will support strong to severe storms.

Tornado Watch #63 valid until 3am CDT. The highest tornado threat is south of the metro.

The main round of heavy rain and thunderstorms will arrive by 10pm with rain and storms continuing through much of the night, moving out by dawn. Total rainfall overnight will likely be around 2". The primary severe weather threats will be damaging wind (as wind near 3000' will be blowing at 60-70 mph and could easily be transported to the surface by a thunderstorm), large hail, copious lightning (put the thundershirt on Fido if you need to), and flash flooding.

We highly recommend having a way of receiving severe weather warnings overnight, a method that will wake you up if dangerous weather is headed your way. A NOAA Weather Radio will do the job, as will reliable severe weather warning apps. We obviously highly recommend the MemphisWeather.net app with StormWatch+ activated and setup to push severe weather alerts to your phone (video: Configuring StormWatch+). StormWatch+ will wake you up, but only if your programmed location is under a Severe Thunderstorm or Tornado Warning. (Link: "Will my phone alert me if I silence it?") Links are at the bottom of this post for info or download. In addition, cell phones should be charging before you go to bed, just in case power outages occur before you have a good charge.

On Thursday, a good part of the day will likely be dry as the atmosphere re-energizes ahead of the next round of potential severe weather. Temperatures will soar into the upper 70s by afternoon with dewpoints in the mid 60s. As a cold front moves into the region, the instability (reflected in CAPE [Convective Available Potential Energy] values of 1500-2000 J/kg, which is plenty sufficient for strong storms) created by the warm, humid air will be lifted by the approach of the front and thunderstorms are expected to develop. Once again, wind energy will be sufficient for strong to severe thunderstorms to form. These storms are likely to be more of the supercell variety, which means the primary threats will be large hail, damaging wind, and potentially tornadoes. The area of most concern is near and east of the Mississippi River, including the metro, from mid-afternoon through the evening. These storms will also be capable of producing torrential rain in their path.

Once again, we recommend keeping a close eye on the weather tomorrow afternoon and evening in particular, and be ready to quickly heed any warnings that are issued. Also, consider your normal afternoon routines for picking up kids and/or commuting home in case storms are ongoing at those times.

An Enhanced Risk (3/5) of severe weather is forecast for most of the metro, where damaging wind, large hail, and a tornado are all possible from mid-afternoon through the evening.

Once the cold front passes in the evening hours (exact time TBD), the severe weather threat ends and we'll be heading into a stretch of cooler, drier days that include the first weekend in April.

Follow MWN on social media via the links below for the latest information and live nowcasting during severe weather events. You can also follow our Twitter feed via the MWN mobile app.

Erik Proseus
MWN Meteorologist

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