Memorial Day Weekend Storms

Memorial Day weekend is one of the busiest holiday weekends of the year. According to the AAA, nearly 40 million people are expected to travel across the nation. This poses a great risk for several areas across the southern United States this weekend due to possible severe weather. This does include Arkansas, hence the reason for posting this blog! It wouldn't be normal if Arkansas didn't have a wild weather swing just in time for a big holiday. Remember, we are still at mid-week, so things could change, but we don't expect much to change. Let's dig into a few specifics!

• The day we are really watching is Saturday. It looks as if Saturday has the potential for some very strong storms. There is a marginal threat for severe weather Friday. We will explain the differentials in these two days in this blog. 
• As of right now (5/24/17) there is no Storm Prediction Center outlook issued for this weekend with the traditional risk areas. However, there is a standard 15% outlook area that does include the WHOLE state. This will be posted below.
• With the whole state in a risk area, this does pose the question for timing. As of right now areas in the western portions of the state should see storms in the late afternoon into the evening hours. The farther east you go, the later in the evening for storm chances.  
• It does appear that all modes of severe weather are possible (mainly Saturday). Damaging winds, large hail, and a few tornadoes; some possibly strong. 

As we mentioned above, the SPC does not have a traditional outlook posted at this time. However, we do have a 15% risk area highlighted. You can see in the graphic posted below, they do indeed have the entire state highlighted for Saturday's possible severe event. We believe that northern, and western, Arkansas has the highest severe probabilities for Saturday. That being said, we cannot rule out severe storm chances in other portions of the state. In fact, it would not be surprising at all if a few tornado and severe thunderstorm warnings went out in far southern, and eastern, Arkansas Saturday evening. 

Saturday SPC Outlook (15% highlight)

Lets dive into Friday's storm chances, which are lower than Saturday. The SPC has a small portion of Northern, Arkansas included in a "marginal" risk area. There will be plenty of instability for storms to work with on Friday. The only problem is there will be a strong capping inversion that should highly limit storm development. We have spoken of the "CAP" before in recent forecasts. When a layer of warm humid air sets up in the atmosphere, this limits severe storms. This is a good thing, and what we want for Friday evening. Should the CAP break, storms could fire up and turn severe quickly. The likelihood of this is low, which is why we aren't spending too much time on this. We have posted the SPC outlook for Friday below. 

Friday Severe Weather Outlook

Now let's take a look at the instability values, or "CAPE" for Saturdays storms. We have included a look here at the NAM 12-km model. As you can see here, very unstable air will be present for most of the state. You will be able to literally feel the instability in the air Saturday. The warm humid air will be extremely abundant, which is needed for that strong-severe storm development. Values at near 6000 J k/g are not unheard of, but not common either. The NAM does have a knack of "over-doing" things sometimes. However, this model really lines up with the other models we've been looking at as well. Regardless, the fuel needed for severe weather will very much be there for Saturday. We will be watching this, and future model runs very close. 

NAM 12-km CAPE Values 

None of the above material is posted to scare anyone, or make anyone pack up their belongings and leave the state. It's May folks, and we live in Arkansas. Severe weather happens, and it looks likely for Saturday. You know we don't sugarcoat things here at Arkansas Weather, but we also don't "hype" weather events. As of now, it appears that the round of storms for Saturday will be fairly strong. Yes, tornadoes are possible, some possibly stronger than the usual squall line spin ups. Stay tuned to the page and we will have updates and any changes as we move closer. We hope you enjoyed the blog, and thanks for keeping up with us. Remember, stay weather aware, and share! God bless.

-AW Team