Severe WX Threat Could Increase for Mississippi

TRENDS ARE BEING MONITORED FOR AN INCREASING SEVERE THREAT...WHICH COULD REQUIRE A WATCH AS EARLY AS 15-17Z.

UPPER SUPPORT FOR RAPID CONVECTIVE DEVELOPMENT THIS MORNING IS A BIT UNCERTAIN. BUT...IT APPEARS A LOW AMPLITUDE SHORT WAVE TROUGH IS IN THE PROCESS OF LIFTING THROUGH THE LOWER MISSISSIPPI VALLEY ...ON THE SOUTHEASTERN PERIPHERY OF LARGER-SCALE CENTRAL U.S. UPPER TROUGH. AND...LATEST RUC GUIDANCE...SUPPORTED BY 12Z RAOB FROM JACKSON...INDICATES THAT INHIBITION IS BECOMING INCREASINGLY NEGLIGIBLE IN MOIST BOUNDARY LAYER WITHIN CONFLUENT PRE-FRONTAL LOW-LEVEL FLOW REGIME ACROSS MUCH OF LOUISIANA AND MISSISSIPPI. EARLY VISIBLE IMAGERY INDICATES CONSIDERABLE CLOUD COVER ACROSS THIS REGION...BUT IT MAY NOT TAKE MUCH SURFACE HEATING TO SUPPORT INTENSIFICATION OF BANDS OF CONVECTION ALREADY DEVELOPING ACROSS THIS REGION. ALTHOUGH MID-LEVEL LAPSE RATES ARE NOT PARTICULARLY STEEP...MIXED LAYER CAPE IN EXCESS OF 1500 J/KG WILL SUPPORT VIGOROUS UPDRAFTS IN THE PRESENCE OF STRONG DEEP LAYER SHEAR BENEATH 50-70 KT 500 MB FLOW. LOW-LEVEL HODOGRAPHS NEAR A 30 TO 50 KT SOUTHWESTERLY 850 JET AXIS REMAIN SIZABLE...AND SUPPORTIVE OF TORNADO POTENTIAL AND THE RISK FOR LARGE HAIL...PARTICULARLY IN MORE DISCRETE STORMS...WHILE DAMAGING WINDS BECOME A THREAT IN DEVELOPING LINE SEGMENTS.