The threat of Severe Weather is increasing for Thursday (Halloween). The timing of the severe weather particularly concerns me due to Halloween. Our most significant threat of Severe Weather since April for NC. The Storm Prediction Center has issued a level 3/5 risk for Severe Weather from Raleigh and Greensboro north; this is where more widespread Severe Weather is expected. A level 2/5 risk has been issued from I95 west into the Mountains and Foothills. Unfortunately, mother nature has decided to make Spooky and Trick a whole new level. No, the world is not going to end not everyone sees Severe Weather like snow or Hurricanes, but it is the time to stay aware and have many ways for alerts. This could be a Potentially dangerous situation for folks that don't have ways to receive warnings.
WHAT: An approaching Cold Front from the west will bring the chance of thunderstorms, and in fact, The Storm Prediction Center has outlined most of Central/Foothills and mountains NC in a level 2/5 and a rarer 3/5 for severe weather. One key ingredient for severe weather is CAPE (convective available potential energy) this critical for the development of severe weather. Models are showing 1000-1500, which is enough for severe storms to fire the more sun we see, the more energy, no matter if we see the sun or not severe weather is expected, just sun exasperates the situation. However, another important "ingredient" is shear; the shear levels are going to be rather high for the Carolina's. Thus Damaging winds and a few tornadoes are certainly likely in the area circled on the map below. A QLCS, which is a fancy name for a squiggly line of storms, will have the greatest threat for damaging winds and embedded Tornadoes. The QLCS will then pose a risk of widespread 40-55 mph winds, locally up to 65-75 mph, and a few mesovortices/tornadoes (embedded tornadoes).
A warm and humid airmass and an approaching Cold Front will combine to produce widespread storms, and many of these could be severe. The best combination of instability and shear will be over Central and Foothills North Carolina, over the "enhanced risk" by SPC where I believe some sunshine will be present. But strong to severe storms are possible statewide Thursday and Thursday night Everyone needs to be weather aware Thursday afternoon and Thursday night, and have a way of receiving warnings in case they are needed and be able to find shelter. There still remains some significant uncertainty is regarding CAPE (convective available potential energy) this important for the development of severe weather.
THREATS: The main mode of Severe Weather Thursday will be damaging winds, however, While winds through the lowest 3 km will remain modest, vertical shear through a deeper layer with winds up to 30-40 kt at 500 mb will support wind profiles at least marginally sufficient for mid-level updraft rotation thus a few embedded tornadoes possible in some storms, but multicellular convection will probably be the dominant mode as storms consolidate into lines and clusters. Strong to damaging wind gusts should be the primary The timing of these storms will be from mid-afternoon to the late afternoon for the mountains and Piedmont (Greensboro west) Central NC will be after 8 PM-11 PM, the threat is rather low for eastern/coast NC due to the timing. This very problematic for the mountains/foothills/Charlotte/Greensboro areas for Trick or Treat.
TORNADOES: Models are showing some very high low and mid-level shear values which, if realized would easily support the formation of a few tornadoes across Central/ Triad/ Triangle/ Charlotte metro. Still some uncertainty on favored locations at this point, likely dependent in large part to surface heating ahead of the line and the eventual strength and placement of the meso-low and attendant triple point. For now, the best Tornado values below on the map are the chances to see a Tornado in 50 miles of you. Any Tornadoes that do form will be rather weak and brief. Models have been trending the potential of discrete cells out ahead of the mainline, this will be something we will watch in later trends.
Any Severe Weather Threat is concerning; tomorrow is more concerning than usual the timing of the Storms will be problematic due to Trick or Treating. These storms will mean business when they pass through, damaging winds and tornadoes the threat more widespread than what we have seen over the past few months. I'd recommend strongly moving Trick or Treating west of Raleigh to Friday night. Central NC should be okay as storms will arrive later in the evening.
WHAT TO DO: Don't freak out I got you covered! Please stay tuned for updates as things and will change, 24/7 updates throughout the storms will occur on North Carolina's Weather Authority. I am closely monitoring the situation, make sure you have many ways to receive severe weather alerts on Thursday. It is imperative that you keep checking for updates tomorrow. Questions please message on the Facebook page not on the website!
CALL TO ACTION: People must have a way of hearing warnings, and that way should never, ever be a siren. Their purpose is only to reach a limited number of people outdoors. Every North Carolina home and business must have a NOAA Weather radio, properly programmed and with a fresh battery backup. Be sure WEA (Wireless Emergency Alerts) are enabled on your phone (check notification settings)... even with no good weather app installed you will receive a tornado warning with a loud audible alert.
If you live in a manufactured home, you have to GET OUT if a tornado warning is issued. Have a shelter identified, or other place identified that is open when you are at risk. Know how to get there quickly.