First Significant Severe Threat This Year For the DMV Tomorrow Night - Tuesday Afternoon

There is a severe weather risk for tomorrow for the western and southern parts of our region, and it may be the first real significant outbreak in the DMV. Tomorrow is mainly a wind and hail threat, but there is a tornado threat too. Most of our region is in the marginal risk, and the rest are in the general risk. I'm pretty sure that this risk will be upgraded to a slight at the very least; maybe an enhanced tomorrow.

This is the risk for tomorrow. The main risk is during Monday afternoon - Tuesday afternoon. Almost all of MoCo is in the marginal risk area, and the rest of the region is in the general risk. I assume that everyone in the general risk will be upgraded to have a severe risk, and marginal at the very least.

This is the wind risk for our region. There is a 5% chance of areas in the green to see 65 or higher MPH winds 25 miles away from any given point. These are winds from thunderstorms, not anything else.

This is the hail risk for our region. There is a 5% chance for areas located in the green to see 1" or larger hail 25 miles away from a certain point. This does not include the chances for <1" hail.

This is the risk for tornadoes in our area. Not all areas in the marginal risk are in the tornado risk. Areas in the green have a 2% chance of seeing any type of tornado 25 miles away from any given point. 

 

This is the 18z HRRR for hour 48, 8 AM EDT Tuesday. It shows 1000-1500 ML CAPE for our county, with up to 2500 MLCAPE in our western regions(yellow), with 500-1000 MLCAPE for our eastern regions(gray). This is a pretty good amount of MLCAPE to work with.

There is a REALLY good amount of lift here. Our county is between -5 to -7 C of lift, and our western regions go up to -11 C of lift! Eastern regions have -4 to -6 C of lift. This is a really good amount!

However, there barely isn't enough shear to support severe weather(25-30kt, you want over 30kt for severe weather). This time, eastern regions have more shear, some regions over 30kt, while western regions have less than 20kt of shear. There still is something though, and we have instability and lift, plus very good dew points (this is hour 48 of 18z HRRR). 

Although this threat is mainly a hail and wind one, there is also a chance for some isolated tornadoes. Check out this NAM 3KM 18z sounding!

This is a pretty good sounding for tornadoes(Gaithersburg MD)! The critical angle is really good, the significant tornado parameter is at 2, suggesting an EF1 or EF0 tornado; possibly low-end EF2. The LCL is pretty low, over 1000 MLCAPE, and good dew point and temperature.

Do I think we will see an EF2 tornado or stronger in our region? No, at least not right now. We will know more tomorrow afternoon after observing data and soundings. Isolated tornadoes are definitely possible though. We will just have to see. I'll make an update tomorrow. Don't get too worried over the chances for severe weather; just be prepared and tell others. It can be dangerous and devastating, but as long as you are prepared, it won't be too bad, and that's all you can do to protect yourself. This not only goes for this specific event, but just severe weather events in general. At the same time, don't get too relaxed. Check the latest forecast on the NWS website so that you know when and if events occur. If you see a tornado or severe thunderstorm warning for your location, get inside and seek shelter! Even if you don't see it, still take shelter! The tornado can be rain-wrapped, meaning that it's very difficult to see, and the storm could be very dangerous, but it hasn't reached you yet. Just be careful, stay safe, be prepared, don't be too anxious, and I will see you tomorrow in the next post!

*Edited by QuackyDucc