Posted on 03/17/2021 9:11:58 AM PDT by janetjanet998
DAY 1 CONVECTIVE OUTLOOK NWS STORM PREDICTION CENTER NORMAN OK 1106 AM CDT WED MAR 17 2021
VALID 171630Z - 181200Z
...THERE IS A HIGH RISK OF SEVERE THUNDERSTORMS WEST-CENTRAL ALABAMA...NORTHERN AND CENTRAL MISSISSIPPI...NORTHEAST LOUISIANA...FAR SOUTHEAST ARKANSAS...
..SUMMARY
A SIGNIFICANT TORNADO OUTBREAK IS EXPECTED WITH NUMEROUS STRONG AND A FEW LONG-TRACK, POTENTIALLY VIOLENT TORNADOES. AN INITIAL ROUND IS EXPECTED TO BEGIN ACROSS EASTERN MISSISSIPPI AND ALABAMA THIS AFTERNOON. A SEPARATE SWATH SHOULD EMANATE FROM SOUTHEAST ARKANSAS TO LOUISIANA THIS AFTERNOON AND SPREAD EAST ACROSS MISSISSIPPI AND ALABAMA THIS EVENING INTO TONIGHT.
.DEEP SOUTH
MINOR CHANGE MADE TO THE CATEGORICAL HIGH RISK AREA TO EXPAND A BIT.
MAIN CHANGE IS TO THE UNDERLYING PROBABILITIES WITH THE ADDITION OF
A 45 TOR AND 45 WIND. A DANGEROUS, LONG-DURATION TORNADO OUTBREAK
EXPECTED TO COMMENCE THIS AFTERNOON AND PERSIST WELL INTO TONIGHT
WITH MULTIPLE ROUNDS OF HEIGHTENED TORNADO POTENTIAL.
ONGOING CONVECTION IS WITHIN AN ARC WITH A PRE-FRONTAL SQUALL FROM
FAR EAST TX TO NORTHEAST AR AND THEN IN A MORE WEST/EAST-ORIENTATION
FROM NORTHEAST AR TO THE AL/TN BORDER AREA. THE NORTHERN ACTIVITY
WILL TEND TO REINFORCE THE SURFACE WARM FRONT APPROACHING THE TN
BORDER WITH MS/AL THIS AFTERNOON. THE SOUTHWEST BAND WILL LIKELY
PERSIST EAST AND SHOULD BREAKUP INTO A BROKEN BAND OF SUPERCELLS AT
SOME POINT THIS AFTERNOON AS LOW-LEVEL SHEAR FURTHER STRENGTHENS
ACROSS THE ARK-LA-MISS REGION. FARTHER EAST, WARM-ADVECTION SHOWERS
IN SOUTHEAST MS TO WEST-CENTRAL AL WILL LIKELY DEEPEN BY EARLY
AFTERNOON INTO A SEPARATE SWATH OF SEVERAL DISCRETE SUPERCELLS IN AN
ENVIRONMENT OF STRENGTHENING LOW TO DEEP-LAYER SHEAR. BETWEEN THESE
TWO AREAS, THE DESTABILIZING WARM SECTOR WITH WARMING BOUNDARY-LAYER
TEMPERATURES AND MID 60S TO LOW 70S DEW POINTS, WILL SUPPORT AN
EXPANSIVE PLUME OF 1500-2500 J/KG MLCAPE.
BY LATE AFTERNOON AND INTO EARLY TONIGHT, A LOW-LEVEL JET SEGMENT
WILL STRENGTHEN TO AT LEAST 50-60 KT ACROSS MS/AL AS THE MIDLEVEL
TROUGH APPROACHES FROM THE WEST, CONTRIBUTING TO VERY STRONG
LOW-LEVEL SHEAR (0-1 KM SRH IN EXCESS OF 300 M2/S2). BUOYANCY WILL
BE SLOW TO DECREASE AFTER SUNSET AND WITH EASTWARD EXTENT BASED ON
THE PREVALENCE OF RATHER RICH BOUNDARY-LAYER DEW POINTS, VERY
FAVORABLE WIND PROFILES (WITH 700-MB WINDS REACHING 70-80 KT) WILL
MAINTAIN THE THREAT FOR LONG-TRACK, INTENSE TORNADOES WITH BOTH
WARM-SECTOR SUPERCELLS, AS WELL AS SUPERCELLS WITHIN THE BROKEN BAND
NEAR AND AHEAD OF THE SURFACE WIND SHIFT PROGRESSING EAST ACROSS MS
BY EARLY TONIGHT. THE STRONG TORNADO AND SIGNIFICANT DAMAGING WIND
THREAT WHILE BECOMING MORE SPATIALLY CONFINED WITH TIME, WILL LIKELY
PERSIST ACROSS PARTS OF AL OVERNIGHT AND SHOULD SPREAD INTO WESTERN
GA BEFORE 12Z.
..GRAMS/BENTLEY.. 03/17/2021
i saw yesterday they might have to upgrade the forecast to “HIGH” probability.....boy, this could get nasty....
Prayers for all.
I believe it. Here in Texas ~ hill country ~ it is so windy. Has been warm, icy, hot, cold, warm, etc. Today it is cool and super windy. Rained last night and was so windy it woke us up. I could see spring time tornadoes springing from this constant weather change. And no, it is NOT climate change!
If CO2 was still at the safe 0.041% instead of the dangerous 0.042% as it is now, this never would have happened
I was born and raised in Georgia. I have never heard anyone use the term ‘deep south’ except people who have never been there.
Yup. The follow on to the storm that just came through NV/CA a couple days ago. Building on that gulf moisture and causing trouble down south. Prayers up.
good place to follow the action with professional meteorologists and knowledgeable amateurs
It’s just the South. NOT the ‘deep south’.
Bkmrk.
How ‘bout Dirty South? Bet you heard that one a time or two.
Here in the Metroplex - AC on yesterday, strong storms last night with some power outages. We’ll need the heat on tonight.
I’ll be on the southern outskirts of this I guess.
We’re across the bay in Baldwin County, AL.
Not looking forward to this.
Rare PDS watch just issued
RGENT - IMMEDIATE BROADCAST REQUESTED
TORNADO WATCH NUMBER 29
NWS STORM PREDICTION CENTER NORMAN OK
1135 AM CDT WED MAR 17 2021
THE NWS STORM PREDICTION CENTER HAS ISSUED A
* TORNADO WATCH FOR PORTIONS OF
WESTERN AND CENTRAL ALABAMA
CENTRAL TO EASTERN MISSISSIPPI
* EFFECTIVE THIS WEDNESDAY MORNING AND EVENING FROM 1135 AM UNTIL
700 PM CDT.
..THIS IS A PARTICULARLY DANGEROUS SITUATION
* PRIMARY THREATS INCLUDE...
NUMEROUS TORNADOES EXPECTED WITH A FEW INTENSE TORNADOES LIKELY
SCATTERED DAMAGING WINDS AND ISOLATED SIGNIFICANT GUSTS TO 80
MPH LIKELY
SCATTERED LARGE HAIL AND ISOLATED VERY LARGE HAIL EVENTS TO 3
INCHES IN DIAMETER LIKELY
SUMMARY...NUMEROUS DISCRETE SUPERCELLS ARE EXPECTED TO DEVELOP THIS
AFTERNOON CAPABLE OF PRODUCING STRONG TO INTENSE TORNADOES.
Deep south would be the area below the fall line. But excluding the Yankee occupied areas of Florida. Some folks might include the non-Yankeefied portions of the Piedmont.
Another way to tell:
Rednecks - deep south
Hillbillies - south
Foreigners - big cities
Oh, yeah.
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