SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0518 PM CDT Fri Nov 01 2024 Valid 031200Z - 091200Z A mid-level trough will deepen across the Interior West on Sunday and will de-amplify while ejecting into the Mississippi Valley by mid-week, when another mid-level trough will amplify across the western U.S. As both mid-level troughs amplify, surface high pressure will build across the Interior West as surface cyclone development takes place across the Plains on Sunday and mid-week. On Days 3 and 6 (Sunday and Wednesday), medium-range guidance shows deep-layer northwesterly flow overspreading California as the backside of the mid-level trough coincides with a surface pressure gradient across the state. Dry and breezy conditions may occur across northern parts of the northern California Valley region, though questions regarding marginal RH dips and fuel receptiveness preclude Critical probabilities in this region. Locally dry and breezy conditions may also occur over the higher terrain-favoring areas around the Los Angeles area Sunday evening into Monday morning. However, the relatively greater threat for dry offshore surface flow in this region may occur on Day 6/Wednesday, when a stronger surface gradient may develop, necessitating the introduction of 40 percent Critical probabilities. ..Squitieri.. 11/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0240 PM CDT Fri Nov 01 2024 Valid 012000Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...20z Update... No changes are needed to the current D1 Convective Outlook. See previous discussion below for more information. ..Thornton/Smith.. 11/01/2024 .PREV DISCUSSION... /ISSUED 1117 AM CDT Fri Nov 01 2024/ ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 PM CDT Fri Nov 01 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE CENTRAL AND SOUTHERN PLAINS... ...SUMMARY... Scattered severe storms are possible, mainly during the late afternoon and evening on Sunday, across parts of the central and southern Great Plains. ...Synopsis... A deep/high-amplitude upper trough will continue advancing steadily eastward across the western U.S. Sunday, and will begin to emerge into the High Plains late. At the surface, an associated cold front will likewise advance eastward out of the Rockies, and should extend from the Upper Mississippi Valley vicinity south-southwestward to the southern Plains by Monday morning. ...Central and southern Plains... The potential for severe weather Sunday is difficult to delineate, given widespread/substantial prior -- and ongoing -- convection across the Oklahoma/northern Texas area. As such, areas of potentially greater destabilization remain uncertain. Despite this, an amply moist warm sector and favorably sheared environment will exist ahead of the advancing upper system, which should support severe storms locally. Therefore, maintenance of a large/rather broad risk area across portions of the central and southern Plains remains the most reasonable forecast. Where greater instability can evolve, potentially on western fringes of the outlook area from western Kansas south across the Texas Big Country, risk for large hail and a couple of tornadoes could evolve. Otherwise, locally damaging wind gusts would appear to be the most likely risk -- which may persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0152 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...NO CRITICAL AREAS... The previous forecast (see below) remains on track. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0159 AM CDT Fri Nov 01 2024/ ...Synopsis... A highly amplified large-scale trough, preceded by strengthening deep-layer southwesterly flow, will advance slowly eastward across the western CONUS. This will promote breezy south-southwesterly surface winds from the Southwest into the High Plains, though a limited overlap with warm/dry conditions and dry fuels should limit the overall fire-weather threat. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 PM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM THE PERMIAN BASIN VICINITY EAST-NORTHEASTWARD INTO SOUTHWESTERN OKLAHOMA... ...SUMMARY... Isolated severe storms are expected Saturday and Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across parts of the Permian Basin and South Plains of Texas during the late afternoon and early evening. ...Synopsis... Digging/intensification -- and gradual/steady progression -- of the western U.S. upper trough is expected Saturday. As this system shifts from the West Coast states across the Great Basin and into the Desert Southwest, substantial downstream mid-level height falls will occur across the central and southern Plains. At the surface, a remnant baroclinic zone -- extending from Texas eastward across the Southeast -- will mark the northern extent of the moist Gulf low-level airmass. This boundary -- in response to persistent southeasterly low-level flow -- should tend to retreat northwestward across Texas/Oklahoma, though likely to become impeded by convective outflow. The result will likely become a convectively reinforced boundary extending from the Permian Basin vicinity east-northeastward into Oklahoma, which will focus persistent, regenerative convection and some attendant severe risk through the period. ...Transpecos region and southeastern New Mexico northeastward into central and northern Oklahoma... Showers and thunderstorms are forecast to be ongoing at the start of the period from southeastern New Mexico northeastward into southern Kansas, with potentially some local/low-end severe risk on the southern fringe of this convection. South of the convection, some heating/destabilization is expected -- particularly across the Transpecos/Permian Basin region. Here, an afternoon increase in convection -- likely in the form of supercells -- is expected to occur. Here, large hail will be possible, along with potential for locally damaging winds, and a couple of tornadoes. Into the evening, convection should increase in coverage -- likely evolving into multiple linear bands, as a low-level jet increases. Though instability should remain lesser with northeastward extent into Oklahoma, owing to relatively weak lapse rates, multiple rounds of banded convection should be accompanied by risk for locally strong wind gusts, along with marginal hail and potentially a tornado or two. This potential should persist well into the overnight hours. ..Goss.. 11/01/2024 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Fri Nov 01 2024 Valid 011700Z - 021200Z The primary changes made to the Day 1 Fire Weather Outlook Update was to expand Elevated highlights into southern Pennsylvania, and northeast to portions of coastal New England. In these areas ahead of the cold front, clearing skies are leading to rapid boundary-layer mixing and lowering of RH. Sustained surface winds are already reaching 20 mph in spots, with higher gusts, and short-range guidance consensus suggests that RH should drop to 30-35 percent RH by mid-afternoon. As such, Elevated fire weather conditions remain likely given the presence of dry fuels. ..Squitieri.. 11/01/2024 .PREV DISCUSSION... /ISSUED 0158 AM CDT Fri Nov 01 2024/ ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1117 AM CDT Fri Nov 01 2024 Valid 011630Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Southern High Plains... Visible-satellite imagery late this morning shows patches of stratocumulus over the Pecos River Valley. This low-level moisture coincides with the northwesterly fringe of richer moisture located over the Hill Country and Deep South TX. The timelapse of water-vapor imagery shows the onset of an amplifying large-scale trough over the West. A lead lower-latitude disturbance over northern Baja and Sonora will shift eastward along the Mexican border during the period and aid in the development of a lee trough over the southern High Plains beneath moderately strong southwesterly mid-level flow. A gradual intensification of low-level warm-air advection downstream of the upper trough will occur through tonight across the southern High Plains. Model guidance continues to indicate widely spaced/isolated thunderstorms will develop late this afternoon and into the evening across Far West TX into southeastern NM as 500-1000 J/kg MLCAPE develops coincident with the increase in low-level moisture. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. ..Smith/Moore.. 11/01/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0754 AM CDT Fri Nov 01 2024 Valid 011300Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Isolated severe hail and/or gusts are possible across parts of the southern High Plains, from this evening into the overnight. ...Synopsis... Today will mark the start of a substantial mid/upper-level pattern amplification over the CONUS. This will be mainly related to a strong shortwave trough now digging southeastward over the Pacific, offshore from OR, and south of a cyclone now covering the BC Coast and adjacent waters. The cyclone will move inland and devolve to an open-wave trough, but also, will phase better with the amplifying shortwave trough. By the end of the period, this should result in a major synoptic-scale trough from southern BC over the Pacific Coast States and offshore from Baja. Associated cyclonic flow then will cover nearly all the CONUS from the High Plains westward, with height falls from the northern/central Rockies to the southern High Plains. At the surface, 11Z analysis showed a low over southern QC, with a cold front southwestward across western portions of NY/PA/WV, eastern KY, middle TN, northern MS, to east and south-central parts of TX. The western part of this frontal zone will decelerate today, become more diffuse, and merge with an inland-shifting, older, marine/warm frontal zone now lying quasistationary near the LA coastline and over deep south TX. The latter boundary will demarcate the northern extent of optimal Gulf moisture, and should shift northward/inland through tonight, but remain southeast of west TX and eastern NM until day 2. Another low, with a weak cold front arching southward over the central High Plains, will dissipate through the period, as lee troughing intensifies just to the west (in advance of the strengthening mid/upper trough). ...Southern High Plains... Isolated to widely scattered thunderstorms are expected to form over portions of far west TX and southeastern NM from late afternoon into evening, as gradually increasing boundary-layer moisture becomes available to diurnally heated higher terrain in the region. Thunderstorm coverage should increase from late this evening through the overnight hours, and begin training within a southwest/ northeast-oriented plume from far west TX to southern KS. This convective growth will be related to strengthening low-level theta-e and moisture, WAA-related large-scale ascent, and weakening MUCINH. The most intense cells embedded in this regime may produce severe hail or gusts, but the overall areal severe threat still appears to be on the marginal side, due to lack of greater instability/buoyancy. In response to trough amplification aloft over the West, low-level warm advection and moisture transport will persist and enlarge into the southern High Plains region, with a 30-40-kt LLJ progged to develop overnight. However this will be an early stage of the return-flow process under modest lapse rates aloft, with considerable residual continental trajectories still involved in low levels, and the most-favorable, Gulf-modified parcels not forecast to reach the region until day-2 and beyond. Though upper 50s to low 60 F surface dewpoints should spread into the Permian Basin region of west TX and southeastern NM tonight, the area of strongest lift farther northwest will have less moisture. MUCAPE of 500-800 J/kg is expected around the time of most of the convective development, increasing to the 1000-1500 J/kg range in non-convective inflow sector by the end of the period. A layer of weaker midlevel flow above the LLJ will restrict vertical shear, keeping effective-shear magnitudes under 30 kt over most of the area. As such, any supercell processes should be isolated and transient in character, especially considering the anticipated upscale evolution to a relatively dense convective-precip corridor. ...TX Rio Grande Valley between DRT-LRD... Widely scattered to scattered thunderstorms should develop this afternoon as the easterly/upslope component of flow impinges on higher terrain of the Serranias del Burro of northern Coahuila, and adjoining higher slopes in the direction of the Rio Grande. Isolated large hail and damaging gusts are possible, but predominantly on the Mexican side of the border. The boundary layer in the valley will be strongly heated and richly moist, with dewpoints from the upper 60s to low 70s F. Given the lack of stronger midlevel flow, however, two related factors render a highly conditional potential on the TX side: 1. Modest deep shear, despite strong veering with height from surface into midlevels. Forecast soundings suggest just 30-35-kt effective-shear magnitudes. 2. Uncertainty about whether orographically initiated convection can remain organized/severe long enough to reach the border. Early-stage supercells, if any, may not survive far enough eastward in that mode, but outflow-dominant/forward-propagating multicellular clusters might. As such, a very conditional severe-gust threat may reach TX. Given the absence of a robust EML and of related MLCINH, deep convection also may develop in the warm sector east of the Rio Grande, amid strong diurnal heating and rich moisture, but the foci for lift are quite unclear at this time. With all these uncertainties, will refrain from an unconditional severe area for this outlook cycle. ..Edwards/Mosier.. 11/01/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Fri Nov 01 2024 Valid 041200Z - 091200Z ...DISCUSSION... Primary severe potential is focused on D4/Monday from parts of the south-central states into the Mid-MS Valley. An emerging squall line should develop early morning Monday (late D3 into early D4) across parts of west TX. This should occur ahead of strong forcing for ascent attendant to a shortwave impulse and mid-level speed max moving through the basal portion of a Southwest trough. Consensus of guidance supports a positive-tilt ejection of this wave into the central states, with multi-day trends of a weaker surface cyclone. This should yield meridional deep-layer flow predominantly paralleling the enlarging squall line. This will also support a largely asymmetrical low-level flow regime, with the core of the low-level jet rapidly advancing north-northeast from the south-central states towards the southern Great Lakes. This should become increasingly separated from the plume of mid 60s surface dew points that should struggle to advect beyond the Mid-MS Valley. The degree of instability with northward extent in OK/KS across the Mid-MS Valley is questionable with abundant preceding convection ahead of the probable squall line. Primary daytime severe threat may be confined to parts of the Red River Valley and TX, with a late-day/nocturnal severe threat extending northeast towards the Mid-MS Valley. With weak mid-level lapse rates limiting instability in the open warm-moist sector, along with the aforementioned synoptic concerns, confidence is low in how widespread and vigorous severe wind/tornado potential will be. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Fri Nov 01 2024 Valid 041200Z - 091200Z ...DISCUSSION... Primary severe potential is focused on D4/Monday from parts of the south-central states into the Mid-MS Valley. An emerging squall line should develop early morning Monday (late D3 into early D4) across parts of west TX. This should occur ahead of strong forcing for ascent attendant to a shortwave impulse and mid-level speed max moving through the basal portion of a Southwest trough. Consensus of guidance supports a positive-tilt ejection of this wave into the central states, with multi-day trends of a weaker surface cyclone. This should yield meridional deep-layer flow predominantly paralleling the enlarging squall line. This will also support a largely asymmetrical low-level flow regime, with the core of the low-level jet rapidly advancing north-northeast from the south-central states towards the southern Great Lakes. This should become increasingly separated from the plume of mid 60s surface dew points that should struggle to advect beyond the Mid-MS Valley. The degree of instability with northward extent in OK/KS across the Mid-MS Valley is questionable with abundant preceding convection ahead of the probable squall line. Primary daytime severe threat may be confined to parts of the Red River Valley and TX, with a late-day/nocturnal severe threat extending northeast towards the Mid-MS Valley. With weak mid-level lapse rates limiting instability in the open warm-moist sector, along with the aforementioned synoptic concerns, confidence is low in how widespread and vigorous severe wind/tornado potential will be. Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0228 AM CDT Fri Nov 01 2024 Valid 031200Z - 041200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM KS TO NORTH TX... ...SUMMARY... Scattered severe storms are possible, mainly during the late afternoon and evening on Sunday, across parts of the central to southern Great Plains. ...Synopsis... A full-latitude mid/upper trough will gradually progress east onto the Prairie Provinces and across the Desert Southwest/northwest Mexico. Multiple upper jet streaks are consistently progged ahead of the trough across the central to southern Great Plains. Mid-level southwesterlies will also strengthen, but the fastest flow will still remain on the backside of the trough before finally ejecting through the base on Sunday night, coincident with a vigorous shortwave impulse. Initial surface cyclogenesis should occur over the central High Plains. This low should reach the Upper Midwest by 12Z Monday, with additional cyclogenesis occurring in west TX. ...Central to southern Great Plains... A complex setup is expected on Sunday into Sunday night with multiple competing elements that should support/hinder severe potential, along with substantial mesoscale uncertainty. As such, a broad level 2-SLGT risk remains warranted at this juncture. Extensive convection is expected late D1 through much of D2 across the southern High Plains into the central and southern Great Plains. Some of this will linger into Sunday, most likely in the OK to north TX area. With persistent low-level warm theta-e advection and upper-level difluence, convection may continue through the diurnal heating cycle. Best chance for severe in this regime may be focused along the trailing outflow/baroclinic zone where it intersects with the west TX dryline. A separate area of severe potential should develop near the central High Plains cyclone in western to central KS. Here, steeper mid-level lapse rates along and another day of moisture influx should be adequate for late afternoon to evening storms. With eastern extent, however, the deleterious effects of persistent OK/north TX convection may yield a more confined/limited MLCAPE plume in KS/NE. A final round of severe convection may develop overnight across west TX as forcing for ascent becomes strong ahead of the aforementioned wave. Across all regimes, mid to upper hodograph elongation should be pronounced, yielding a conditionally favorable environment for supercells and organized clusters. ..Grams.. 11/01/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...NO CRITICAL AREAS... ...Synopsis... A highly amplified large-scale trough, preceded by strengthening deep-layer southwesterly flow, will advance slowly eastward across the western CONUS. This will promote breezy south-southwesterly surface winds from the Southwest into the High Plains, though a limited overlap with warm/dry conditions and dry fuels should limit the overall fire-weather threat. ..Weinman.. 11/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0159 AM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...NO CRITICAL AREAS... ...Synopsis... A highly amplified large-scale trough, preceded by strengthening deep-layer southwesterly flow, will advance slowly eastward across the western CONUS. This will promote breezy south-southwesterly surface winds from the Southwest into the High Plains, though a limited overlap with warm/dry conditions and dry fuels should limit the overall fire-weather threat. ..Weinman.. 11/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Fri Nov 01 2024 Valid 011200Z - 021200Z ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ..Weinman.. 11/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0158 AM CDT Fri Nov 01 2024 Valid 011200Z - 021200Z ...Synopsis... On the backside of a midlevel trough tracking east-northeastward across the Northeast, deep tropospheric drying will occur across portions of the Mid-Atlantic behind a related cold front. A tight pressure gradient and enhanced low-level flow will yield 15 mph sustained westerly surface winds (with gusts upwards of 25-30 mph). These winds will overlap 25-35 percent RH behind the front during the afternoon, and given very dry fuels across the region (90th percentile ERCs), a few hours of elevated fire-weather conditions are expected. While there will be some potential for isolated early-day showers along the front, this activity should be too light and/or isolated to have an appreciable impact on the receptive fuels. ..Weinman.. 11/01/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1245 AM CDT Fri Nov 01 2024 Valid 021200Z - 031200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE PERMIAN BASIN AND SOUTH PLAINS OF WEST TX... ...SUMMARY... Isolated severe storms are possible on Saturday into Saturday night across parts of the southern Great Plains. The most likely corridor for a couple tornadoes and large hail is across a part of the Permian Basin and South Plains of west Texas during the late afternoon and early evening. ...Southern Great Plains... Widespread convection will be ongoing at 12Z Saturday over the southern High Plains, centered on southeast NM to the Panhandles, within a robust low-level warm theta-e advection regime. A semi-organized linear cluster may be present along the southern edge of the convective swath, and could be maintained through the diurnal heating cycle. Low to mid-level lapse rates downstream will be weak, suggesting localized strong gusts early. A mesoscale corridor of sustained supercell potential is evident over parts of the Permian Basin and South Plains from mid-afternoon to early evening. Regenerative convective development is expected in the wake of morning activity, along the effective outflow-reinforced baroclinic zone arcing to the west-southwest. Best potential for boundary-layer heating will be across the TX Trans-Pecos. Downstream of a full-latitude trough from the Canadian Rockies to the northern Gulf of CA, a strengthening upper jet over northern Mexico should overspread the Trans-Pecos late day. This will yield favorable mid to upper-level hodograph elongation with southwesterly speed shear immediately downstream. A couple longer-lived supercells may develop and move along the mesoscale outflow boundary, with a threat for golf- to tennis-ball-sized hail, despite moderate mid-level lapse rates. With an early evening increase in the low-level jet, a couple tornadoes may develop as well. Mid-level lapse rates will be weaker with a more moist-adiabatic profile extending northeastward into OK. Still, with the evening increase in the low-level jet, potential will exist for low-level rotation with embedded convection along the baroclinic zone. While convective mode will be messy, and uncertainty exists with the spatial placement of the corridor in the wake of daytime convection, the persistent influx of mid 60s surface dew points suggests a low-probability tornado/wind threat may extend into Saturday night. ..Grams.. 11/01/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1145 PM CDT Thu Oct 31 2024 Valid 011200Z - 021200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF EASTERN NEW MEXICO AND WESTERN TEXAS... ...SUMMARY... Scattered thunderstorms, a few which may become capable of marginal hail/wind, will likely evolve across parts of the southern High Plains from this evening into the overnight. ...Synopsis... Moderate west to southwest flow aloft will stretch from the Plains into the Northeast today, with a broad upper trough across much of the West. A strong embedded wave will drop southward overnight from OR/CA into the Great basin, providing cooling aloft. Ahead of this system, gradual height rises will occur over the southern Plains as the western system amplifies. At the surface, high pressure will exist from the Great Lakes southward toward the northern Gulf Coast, with moist low-level easterly winds across the western Gulf of Mexico and into TX. By the end of the period 12Z Saturday, lower 60s F dewpoints will be as far west as the TX/NM border. ...TX... Gradual moistening of the air mass will occur across TX for much of the period, with increasing warm advection around 850 mb overnight as the upper trough amplifies to the west. Still, wind speeds will not be particularly strong, perhaps around 30-40 kt over west TX by 12Z Saturday. Although gradual warming aloft is forecast overnight, 500 mb temperatures around -10 C will still exist around the latitude of Midland. With lower 60s F dewpoints at this elevation, MUCAPE will likely exceed 1000 J/kg, while deep-layer effective shear increases to around 35 kt. Thunderstorms will likely form after 03Z over much of eastern NM and far west TX, eventually spreading into the far western TX Panhandle and South Plains. Generally veering and increasing winds with height may favor a few transient storms capable of marginally severe hail, though some midlevel weakness in wind speeds is noted. As such, a Marginal Risk for hail appears warranted tonight, perhaps as far southwest as El Paso TX. ..Jewell/Weinman.. 11/01/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0712 PM CDT Thu Oct 31 2024 Valid 010100Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through Friday morning. Scattered thunderstorms persist this evening near a weak surface trough extending from far southern TX into LA and MS. These storms remain in a weakly sheared environment, well south of the shortwave trough moving across the upper Great Lakes. While the environment is moist and marginally unstable, severe weather is therefore unlikely. ..Jewell.. 11/01/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0712 PM CDT Thu Oct 31 2024 Valid 010100Z - 011200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through Friday morning. Scattered thunderstorms persist this evening near a weak surface trough extending from far southern TX into LA and MS. These storms remain in a weakly sheared environment, well south of the shortwave trough moving across the upper Great Lakes. While the environment is moist and marginally unstable, severe weather is therefore unlikely. ..Jewell.. 11/01/2024 Read more

No watches are valid as of Thu Oct 31 21:34:02 UTC 2024.