DAY 1 CONVECTIVE OUTLOOK
NWS STORM PREDICTION CENTER NORMAN OK
1030 AM CST WED JAN 18 2023
VALID 181630Z - 191200Z
...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SABINE AND LOWER
MS/OH VALLEYS...
..SUMMARY
A FEW TORNADOES AND SCATTERED DAMAGING WINDS REMAIN POSSIBLE THIS
AFTERNOON FROM THE SABINE VALLEY TO THE MID-SOUTH, WITH MORE
ISOLATED COVERAGE CONTINUING INTO THIS EVENING ACROSS THE LOWER OHIO
AND MISSISSIPPI VALLEYS.
..SABINE AND LOWER MS/OH VALLEYS
MINIMAL CHANGE APPARENT FOR THIS OUTLOOK WITH A BROKEN BAND OF
THUNDERSTORMS WITHIN THE WARM CONVEYOR AHEAD OF THE EASTERN-MOVING
COLD FRONT. THE SEVERE THREAT WILL LIKELY PEAK THIS AFTERNOON FROM
THE SABINE VALLEY INTO THE MID-SOUTH WHERE 60S SURFACE DEW POINTS
(INCREASING TO THE SOUTHWEST) SUPPORTS MLCAPE OF 500-1000 J/KG. THE
ORIENTATION AND TRACK OF THE SHORTWAVE TROUGH OVER THE CENTRAL GREAT
PLAINS SUGGESTS THAT MID-LEVEL LAPSE RATES WILL WEAKEN THIS
AFTERNOON, ALONG WITH INCREASINGLY VEERED LOW-LEVEL FLOW DIMINISHING
HODOGRAPH CURVATURE OVER THE SOUTHERN PORTION OF THE CONVECTIVE
THREAT IN TX/LA. THIS WILL LIKELY MAINTAIN STP VALUES IN THE 1-2
RANGE THIS AFTERNOON BEFORE DIMINISHING LATER. A FEW TORNADOES
APPEAR POSSIBLE, WITH THE DAMAGING WIND THREAT INCREASING SOME AS
THE BROKEN LINE CONSOLIDATES INTO A BROADER QLCS.
CONFIDENCE IS DECREASING WITH THE LONGEVITY OF AN APPRECIABLE
TORNADO AND WIND THREAT BEING MAINTAINED THIS EVENING. BULK OF
MORNING CAM AND MACHINE-LEARNING GUIDANCE ARE INSISTENT ON
DIMINISHING CONVECTIVE INTENSITY TOWARDS 00Z, DESPITE STRENGTHENING
OF THE SOUTH-SOUTHWESTERLY LOW-LEVEL JET. SURFACE-BASED INSTABILITY
SHOULD EVENTUALLY BECOME PINCHED OFF IN THE MID-SOUTH THROUGH
EASTERN MS AFTER SUNSET. THIS SETUP APPEARS LIKELY TO YIELD A
DECREASING, BUT STILL A PERSISTENT LOW PROBABILITY WIND/BRIEF
TORNADO THREAT LINGERING TONIGHT.
..SOUTHEAST KS
AS THE SHORTWAVE TROUGH MOVES EAST ACROSS KS, A SMALL CORRIDOR OF
OPPORTUNITY FOR SURFACE HEATING AND STEEPENING LOW-LEVEL LAPSE RATES
IS POSSIBLE NEAR AND EAST-SOUTHEAST OF THE ASSOCIATED SURFACE
CYCLONE, BENEATH THE MID-LEVEL DRY SLOT. IN THE WAKE OF MORNING
RAINFALL, THERE MAY BE SCANT MLCAPE APPROACHING 250 J/KG. THIS COULD
BE BARELY ADEQUATE FOR A LOW-TOPPED SUPERCELL WITH SMALL TO
MARGINALLY SEVERE HAIL AND A BRIEF WEAK TORNADO POSSIBLE.
