SPC 1630Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1124 AM CDT Thu Apr 25 2024 Valid 251630Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS WESTERN KS AND TONIGHT ACROSS NORTHWEST TX INTO CENTRAL OK... ...SUMMARY... Very large hail up to 3 inches in diameter and a strong tornado or two will be possible this evening across western Kansas. Large hail, damaging winds to 70 mph and a few tornadoes will be possible tonight from northwest Texas into central Oklahoma. ...Synopsis... Morning water vapor imagery shows a negatively-tilted shortwave trough rotating across UT/AZ, with an associated 70kt mid-level jet max moving into NM. This system will eject into the central/southern Plains this evening/tonight, resulting in multiple clusters of severe thunderstorm activity. ...Western KS... A quasi-stationary surface boundary extends from northwest CO into northwest KS. Visible imagery shows broken cloud cover across western KS this morning, with dewpoints in the low 60s to the south of the front. Strong heating will likely ensue through the afternoon, resulting in deepening mixing to the east of the dryline and eventual isolated thunderstorm development. CAM solutions differ significantly on coverage of convection, but it appears likely that at least isolated supercells will form along the dryline, capable of very large hail, damaging winds, and a few tornadoes (possibly strong). The confidence of initiation is much higher along the warm front from northeast CO into northwest KS, and forecast soundings along this corridor show strong low-level vertical shear supporting supercell structures. It is uncertain how far north these storms can remain surface-based, but there is an apparent tornado risk (possibly strong) along the immediate boundary and a large hail risk for some distance northward. This activity will likely spread into south-central NE after dark. ...TX Panhandle/Western OK... As the primary upper trough ejects this evening, large-scale height falls and forcing will overspread the dryline across the OK/TX Panhandles. Forecast soundings show a persistent capping inversion along the dryline, and CAM guidance generally shows very isolated convective initiation. Any storm that forms will pose a risk of all severe hazards, including very large hail. Overnight, a strengthening low-level jet over west TX will likely lead to a large cluster of thunderstorm. These storms will track northeastward across northwest TX and into western/central OK in the pre-dawn hours. Large hail will be likely with these storms, but damaging winds and isolated tornadoes will also be a risk if a more organized linear MCS can evolve. ..Hart/Moore.. 04/25/2024 Read more View the full article

SPC Day 1 Fire Weather Outlook Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Thu Apr 25 2024 Valid 251700Z - 261200Z ...CRITICAL FIRE WEATHER AREA FOR THE SOUTHERN HIGH PLAINS AND SOUTHERN NEW MEXICO... Elevated to critical conditions have started to develop across southeast New Mexico. Expect these conditions to expand/worsen through the day as mid-level flow strengthens and lee cyclogenesis continues. Expanded the Elevated delineation slightly farther north based on current and expected position of the front and dryline. Otherwise, no changes were necessary. See previous discussion below. ..Bentley.. 04/25/2024 .PREV DISCUSSION... /ISSUED 0114 AM CDT Thu Apr 25 2024/ ...Synopsis... A midlevel trough will track eastward across the Southwest, while an accompanying 60-70-kt midlevel southwesterly jet overspreads southern NM and the southern High Plains. This will promote rapid deepening of a lee cyclone over eastern CO, while a southward-extending dryline sharpens over west TX. This large-scale pattern evolution will yield an expansive area of critical fire-weather conditions across the aforementioned areas, with high-end critical conditions expected over eastern NM. ...Southern New Mexico and the Southern High Plains... Behind the sharpening dryline, strong downslope warming/drying and diurnal heating will contribute to a deep/dry boundary layer, characterized by surface temperatures in the mid/upper 80s and single-digit to lower-teens RH. Here, a tightening surface pressure gradient peripheral to the deepening lee cyclone, and mixing into the strong flow aloft, will support 25-35 mph sustained southwesterly surface winds (with gusts upwards of 45 mph). These conditions will yield an expansive area of high-end critical fire-weather conditions, given modestly receptive fuels. The overlap of strongest winds and lowest relative humidity is expected over eastern NM, where extremely critical meteorological conditions are likely. However, a lack of abundant and very dry fuels over the area precludes such highlights at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more View the full article

SPC 1300Z Day 1 Outlook Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0731 AM CDT Thu Apr 25 2024 Valid 251300Z - 261200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS THIS EVENING ACROSS WESTERN KS AND TONIGHT ACROSS NORTHWEST TX INTO CENTRAL OK... ...SUMMARY... Very large hail up to 3 inches in diameter and a strong tornado or two will be possible this evening across western Kansas. Large hail up to 2.5 inches in diameter, damaging winds to 70 mph and a few tornadoes will be possible tonight from northwest Texas into central Oklahoma. ...Synopsis... A midlevel shortwave trough and associated 70 kt jet will eject northeastward toward western KS by late tonight and Friday morning. An associated lee cyclone is expected to deepen this afternoon across northeast CO, with a sharpening dryline arcing to its south across western KS and the TX/OK Panhandles. Farther east, a warm front will continue to move northward from OK into KS, though northward progress of the front will be slowed by elevated convection (posing an isolated large hail threat) that will reinforce the cool side of the boundary during the day. A somewhat bimodal threat distribution is expected - the warm sector in western KS and a second corridor overnight from northwest TX into OK. ...Western KS this afternoon/evening... An unstable warm sector will be present through this evening, with boundary-layer dewpoints in the 60s beneath steep midlevel lapse rates. The base of the elevated mixed layer will be relatively warm, suggesting the need for surface temperatures into the 80s on the immediate moist side of the dryline. The better potential for storm development this afternoon will be across western KS, where dryline parcel residence times will be longer and in closer proximity to the left-exit region of the approaching mid-upper jet. The initial dryline storms will likely become supercells capable of producing very large hail of 2-3 inches in diameter, and these storms could continue northeastward as elevated supercells atop the warm front. The potential for a strong tornado or two will increase this evening as the storms encounter richer low-level moisture and increasing low-level shear. However, the window of opportunity will not be particularly large given the presence of a rain-reinforced front to the northeast and increasing convective inhibition by late evening. ...Northwest TX into OK overnight... A general consensus of most overnight forecast guidance suggests a southern corridor of greater hail/wind threat starting early tonight just off the Caprock and then spreading northeastward over northwest TX into southwest/central OK early Friday morning. Thunderstorm initiation will become more probable by 03-06z in association with cooling/moistening at the base of the elevated mixed layer, coincident with the beginning of eastward movement of the dryline/Pacific cold front along the trailing influence of the ejecting midlevel trough. Storm mode will likely trend to clusters/line segments while spreading northeastward. Boundary-layer dewpoints approaching the upper 60s beneath steep midlevel lapse rates will contribute to MUCAPE in excess of 2000 J/kg through the overnight hours, which will favor the potential for both large hail (especially with any embedded supercells) and damaging winds of 60-70 mph. A few tornadoes may also occur with embedded circulations as low-level shear increases tonight. ...TX Panhandle/western OK this afternoon/evening... A conditionally favorable environment for supercells with very large hail and tornadoes will exist this afternoon/evening across the eastern TX Panhandle into western OK. The primary uncertainty here will be lingering convective inhibition and substantial uncertainty in storm coverage/location along the dryline. For these reasons, have lowered the overall severe threat, but maintained some conditional significant severe potential. ..Thompson/Kerr.. 04/25/2024 Read more View the full article

No Mesoscale Discussions are in effect as of Thu Apr 25 12:01:02 UTC 2024.View the full article

No watches are valid as of Wed Apr 24 03:02:01 UTC 2024.View the full article