Severe Storm Risk - Boxley, AR

There is a Marginal Severe Storm Risk for your location. Continue reading for today's outlook from the National Weather Service's Storm Prediction Center. -------------------- National Severe Storm Outlook THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN AND CENTRAL PLAINS INTO THE LOWER MISSOURI VALLEY SUMMARY Severe thunderstorms with damaging wind gusts and a few tornadoes are expected across parts of the southern and central Plains from this afternoon into tonight. Southern and Central Plains/Ozarks/Lower Missouri Valley An upper-level trough will move across the southern Rockies today and into the southern High Plains. Ahead of the system, the exit region of a mid-level jet will overspread the southern and central Plains this afternoon and evening. At the surface, a cold front will advance southeastward across the central High Plains as a pre-frontal trough moves into the southern and central Plains. Ahead of this feature, moisture advection will take place with surface dewpoints gradually increasing into the mid to upper 60s F over much of Texas, Oklahoma and the eastern half of Kansas. Across the moist sector, RAP forecast soundings suggest that MLCAPE will only peak in the 1000 to 1500 J/kg range. As surface temperatures warm and low-level convergence becomes maximized near the pre-frontal trough in the afternoon, convective development will take place. Thunderstorms are expected to gradually increase in coverage from the afternoon into the early evening, as several line segments organize and move east-northeastward across the moist sector. The convective mode is the main question for this event. It seems possible that the convection will line out quickly during the afternoon, and that discrete cell formation will be minimized. Even so, widespread large-scale ascent and strong deep-layer shear will likely support severe thunderstorm development with vigorous updrafts associated with organized lines and potentially semi-discrete supercells. The latest RAP forecast soundings from central Oklahoma north-northeastward into eastern Kansas suggest that 0-6 km shear will be around 50 knots. Although some directional shear is present, the stronger component will be speed increases with height in the low-levels. Near the axis of the low-level jet, 0-3 km storm-relative helicity is forecast to peak in the 250 to 300 m2/s2 range. This will support a tornado threat with supercells and with rotating elements embedded in organized line segments. Severe wind gusts will also be possible with the more intense line segments, especially with bowing structures. A greater tornado threat could materialize across Oklahoma or southeast Kansas, if a cluster of discrete cells can persist into the late afternoon or early evening. A severe threat will continue throughout the evening as a larger-scale line segment moves eastward across the moist sector, reaching western Missouri and far eastern Oklahoma around midnight. Severe wind gusts and perhaps a QLCS tornado threat will be possible with this line. Texas Southwesterly cyclonic mid-level flow will be in place today across much of Texas, as an upper-level trough approaches. Ahead of the system, an axis of moderate instability will develop as surface temperatures warm. A capping inversion will be in place over much of Texas into afternoon. This cap will likely weaken during the mid afternoon, allowing for convective initiation over parts of west-central and northwest Texas. A convective band, with a mixed mode, is expected to form and move eastward into north-central Texas by early evening. Ahead of this forecast band by 00Z, surface dewpoints are expected to peak in the upper 60s F, with MLCAPE reaching the 2000 to 2500 J/kg range. This will be favorable for strong updrafts and scattered severe storms. The southeastern edge of the mid-level jet will create moderate deep-layer shear along the axis of instability. This will support supercell development with cells that can remain discrete. Intense line segments are also expected with cells that congeal. Severe wind gusts and a couple tornadoes will be possible during the late afternoon and early to mid evening. The greatest tornado threat should be concentrated in north-central Texas where low-level shear is maximized on the southern edge of the low-level jet.