Severe weather update, 725 pm

This was the Memphis radar (reflectivity, or rain intensity, on top, and velocity on bottom) just before 700 pm.  A bow echo moved in to that area, and may have also spun up a tornado.  Either way, the radar was picking up 60 knot winds (about 70 mph) very close to the radar, meaning the radar beam is just above the ground, so some places are likely getting winds 60-70 mph in the Memphis area and on into NW MS.   Memphis airport recorded a gust to 51 mph with constant lightning, 62 mph was reported at Osceola, MS, and numerous reports of wind damage have been received, including large trees down and trucks being blown over on I-55.

This is the line of storms we will deal with later tonight.  It remains to be seen how well they will hold together, as we’ve lost the heating of the day.  However, with air cooling aloft later tonight, dewpoints near 60, and temperatures holding in the mid to upper 60s, the storms should stay strong at least into the western part of Alabama, and probably to BHM. 

As we have mentioned today, the main threat is damaging straight line winds, with low-level wind fields very strong (up to 75 knots, or 85 mph, at 850 mb).  Thunderstorm downdrafts will bring some of this air down to the ground, causing wind gusts in most areas of 40-50 mph, and in some locations over 70 mph.  Trees will likely go down, and power outages are possible.  These winds could knock down large trees and do property damage.  Please have a NOAA Weather Radio on tonight when you go to bed, or set an alarm and get up and check the weather.

The storms are moving a little faster than we thought, and could arrive in NW Alabama as early as 10 pm, and in BHM by 1 or 2 am.

Category: Severe Weather