Mesoscale Discussion 0844 NWS Storm Prediction Center Norman OK 0748 PM CDT Sun May 19 2024 Areas affected...parts of west central into north central Oklahoma Concerning...Severe Thunderstorm Watch 260... Valid 200048Z - 200245Z The severe weather threat for Severe Thunderstorm Watch 260 continues. SUMMARY...A long-lived isolated supercell storm may be maintained at least another couple of hours, possibly impacting at least northern portions of the Greater Oklahoma City area by 10-11 PM CDT, with a risk for large hail in excess of 2 inches, strong, damaging wind gusts and perhaps a continuing risk for a tornado. DISCUSSION...Embedded within southwesterly deep-layer mean flow on the order of 30-35 kt, an isolated intense supercell has been slowly propagating eastward, away from the initiating dryline, to the north of the Clinton-Sherman vicinity. Low-level hodographs have been enlarging some, and a more notable increase in low-level shear is forecast through 04-06Z, along a strengthening southerly 850 mb jet (in excess of 50 kt) from northwest Texas toward the Medicine Loge KS area. However, with the onset of diurnal boundary-layer cooling, inhibition across and east of the dryline is already in the process of increasing, and lower/mid-tropospheric warming forecast across much of Oklahoma this evening will contribute further to this. Even so, given the favorable shear beneath a seasonably strong westerly mid/upper jet nosing into the south central Great Plains, and the strong potential instability eastward into the I-35 corridor, it is possible that the ongoing supercell may be maintained another couple of hours, eastward through northern portions of the Greater Oklahoma City area. ..Kerr.. 05/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OUN... LAT...LON 36039866 36089809 36029705 35899679 35629702 35609754 35559807 35679862 36039866