A brief morning update with some quick notes on some of the overnight guidance which seems to be trying to key in on a few areas of heightened concern across our area.
Recall that the forecast calls for…
EVERYONE – Brief heavy rain, lightning, and wind gusts up to 40mph
MOST PEOPLE – Brief heavy rain, lightning and wind gusts up to 45mph
MANY AREAS – A few rounds of heavy rain, lightning, wind gusts up to 50mph and small hail
SOME FOLKS – Multiple rounds of heavy rain, frequent lightning, wind gusts up to 60mph and small hail
A FEW LOCATIONS – Multiple rounds of heavy rain, frequent lightning, wind gusts up to 65mph, and large hail
SELECT SPOTS – Multiple rounds of heavy rain, localized flash flooding, frequent lightning, win gusts up to 75mph, large hail and a tornado (up to EF4 in strength)
And the county-by-county forecast will walk you through the forecast, timeline, and possibilities for your area. I wanted to take a few minutes this morning and highlight what some of the short-range guidance is showing this morning from some of the overnight data.
The short-range guidance is showing two avenues where the parameter space – as well as the storm-mode and storm interactions – will foster a potent environment for strong tornadoes.
I want to stress: this does not mean that areas outside of these red circles are in the clear. Not at all. Tornadoes are still possible beyond these zones. Strong tornadoes are still possible outside of these zones, too
However, if you are inside these red circles, I need you to be especially alert today. The models suggest that these areas may have the most supportive conditions for tornado formation in our area, so staying weather-aware is crucial.
The timeline for this is still looking like between (about) 10a and 6p, depending on your specific location. So a pretty wide window. The county-by-county forecast is still up (follow the link above) and still holds.
WHAT CAN CHANGE?
Looking at some of the factors in place, overnight we didn’t see quite as much convection fire up. That means the outflow boundaries may be fewer and farther between, allowing for storms to remain discrete without another storm firing up just down the road.
I know last night I talked about how if there were fewer storms that may end up helping us out because, with no cap, we may get storms to fire more quickly and then they’d all clump together. That is still possible. As of about 730, in Hattiesburg, the temperatures was 75 and the dewpoint – very important on days like today – was only 66.
Model guidance from this morning thought, actually, we were slightly cooler and more humid. With a stronger cap of warm air above us, holding down any potential storms from firing up.
Model guidance shows that cap eroding away by 11am – that is when storms should start to imitate. But if we are warmer and drier, it means that cap isn’t quite as strong and storms may fire up a bit earlier. Not as fully-fledged severe storms, but as instability showers and little low-topped thunderstorms.
If these grow fast enough, we could still clump things together and mitigate the threat for storms across a wide area.
BUT!
If a few of these can get rooted and develop more substantial updrafts, they would be able to tap into a lot of “good” stuff needed for tornado development. And the “best” stuff of the “good” stuff is in the red circled areas above.
That would happen around lunchtime.
I know we are dealing with a lot of “ifs” and “mays” and “coulds” here,. but that is unfortunately the world of weahter forecasting – particularly during high-impact events where we are waiting how the atmosphere reacts to things that are in a delicate balance.
