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SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0258 PM CDT Thu Oct 17 2024 Valid 181200Z - 191200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF VENTURA...LOS ANGELES...SAN BERNARDINO...AND RIVERSIDE COUNTIES IN SOUTHERN CALIFORNIA... A Critical area was added over portions of Ventura, Los Angeles, San Bernardino, and Riverside Counties in southern California. The latest high-resolution guidance consensus lends increased confidence in the overlap of strong offshore winds (gusts ranging from 45 to 55 mph) and single-digit to lower-teens RH on Friday morning/afternoon, and potentially again during the early morning hours on Saturday. The best overlap of the strong/gusty winds and low RH are expected over the typical wind-prone valleys/mountains (e.g., San Gabriel, Santa Monica, and Santa Ana Mountains and foothills). Upon coordination with the local forecast offices, fuels are supportive of large-fire spread, warranting the upgrade to Critical. Elsewhere, the previous forecast (see below) remains on track. ..Weinman.. 10/17/2024 .PREV DISCUSSION... /ISSUED 0153 AM CDT Thu Oct 17 2024/ ...Synopsis... As a surface low settles into the Southwest, strong southerly flow will continue across the Central and Southern Plains. This low-level flow will advect moisture northward which will eliminate most of the fire weather concern across the Plains. Very strong mid-level flow will overspread the Southwest as a compact upper-level cyclone slides east-southeast. Sustained winds of 30+ mph are likely beneath the strongest mid-level flow. Fuels across Arizona and New Mexico are not critically dry and therefore, no fire weather concerns have been highlighted at this time. However, dry fuels are present across California where some Elevated fire weather conditions are likely within the Central Valley, Coastal Ranges of the central and northern portions of the state, and in terrain favored areas of southern California. In addition to the strong winds Friday afternoon, the Santa Ana winds will likely strengthen again 06-12Z Saturday. This will occur as the LAX-TPH gradient strengthens to near 10-12 mb as diurnal cooling, and high pressure in the Great Basin strengthens the pressure gradient across southern California. ...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 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0236 PM CDT Thu Oct 17 2024 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not expected through tonight. ...20z Update... The previous outlook remains valid with no changes. Scattered thunderstorms are possible across the Great Basin and Rockies ahead of a deep upper trough and cold front this afternoon through tonight. An isolated stronger storm may be capable of strong outflow wind gusts, but organized severe storms are not expected. See the prior outlook for additional information. ..Lyons.. 10/17/2024 .PREV DISCUSSION... /ISSUED 1110 AM CDT Thu Oct 17 2024/ ...Western States... A large upper trough will dig southeastward across the mountainous west today and tonight. This will provide increasing large-scale ascent and increasing mid-level moisture for scattered showers and thunderstorms across much of the Rockies and Great Basin. Visible satellite imagery shows widespread high clouds over much of this area, which should limit daytime heating and destabilization. Strengthening winds aloft could pose a risk for gusty winds in the strongest cells this afternoon, but the risk of severe storms appears low. Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0159 PM CDT Thu Oct 17 2024 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible across the southern High Plains Saturday into Saturday night, accompanied by at least some risk for severe weather. ...Southern High Plains vicinity... An upper low over the Four Corners vicinity will only shift slight northeast through the forecast period. On the eastern periphery of this system, moderate deep-layer south/southwesterly flow will persist over the southern High Plains. Southeasterly low-level flow will maintain mid to upper 50s F dewpoints across the region, with decreasing boundary-layer moisture with northward extent into the central Plains. A weak surface trough/dryline will remain nearly stationary through the period, resulting in low-level convergence in a weak upslope flow regime. Cloudiness and ongoing showers/thunderstorms will limit heating. However, modest boundary-layer moisture beneath 7-7.5 C/km midlevel lapse rates will support weak instability (up to 1000 J/kg MLCAPE). Furthermore, vertically veering supercell wind profiles will support isolated organized convection. The overall pattern will remain similar to that expected in the Day 2/Friday period, and at least a low risk for severe storms is expected to persist on Day 3/Saturday. ..Leitman.. 10/17/2024 Read more

924
ABPZ20 KNHC 171729
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Thu Oct 17 2024

For the eastern North Pacific...east of 140 degrees west longitude:

South of Southwestern Mexico:
An area of low pressure is expected to form during the middle part
of next week well offshore of southwestern Mexico. Thereafter,
gradual development is possible as the system moves westward at 10
to 15 mph.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Bucci

Voluntary water conservation was urged in northern Delaware as surface water is the main source of drinking water in the northern part of the state. WDEL.com (Wilmington, Del.), Oct 17, 2024

Below normal rainfall during the growing season reduced crop yields and in more extreme cases left no crop to harvest. Some corn was cut down without being harvested, according to the Delaware Farm Bureau executive director. Some soils were so dry that cover crops and small grains that are being planted cannot germinate for lack of moisture. WDEL.com (Wilmington, Del.), Oct 17, 2024

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Thu Oct 17 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible Friday night across parts of eastern New Mexico near the Sangre de Cristo and Sacramento Mountains. Some may pose a risk for small to marginally severe hail, locally damaging wind gusts, and perhaps a tornado. ...Southwest into the Southern High Plains... An upper low will develop within the base of a western trough on Friday. This system will progress across the Southwest toward the Four Corners/southern Rockies vicinity by Saturday morning. As this occurs, moderate mid/upper south/southwesterly flow (40-60 kt at 500 mb) will overspread the southern Rockies and adjacent High Plains. At the surface, modest boundary layer moisture will spread across southern AZ on southerly low-level flow ahead of an eastward-advancing cold front. Steepening midlevel lapse rates within the developing mid/upper low may provide weak elevated instability and isolated thunderstorms are possible. Further east, southeasterly low-level flow will transport modest Gulf moisture northwest across western Texas into eastern New Mexico along a surface trough/dryline. As the upper low/trough approaches during the afternoon into the evening, steepening midlevel lapse rates and surface dewpoints in the mid 50s F will support up to 1000 J/kg MLCAPE. Vertically veering wind profiles with around 40 kt effective shear magnitudes suggest isolated supercells will be possible with initial convection during the evening. More linear development may occur with time (toward 06z) as stronger large-scale ascent overspreads the region. Strong gusts, marginal hail and a tornado or two will be possible with this activity. ..Leitman.. 10/17/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Thu Oct 17 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible Friday night across parts of eastern New Mexico near the Sangre de Cristo and Sacramento Mountains. Some may pose a risk for small to marginally severe hail, locally damaging wind gusts, and perhaps a tornado. ...Southwest into the Southern High Plains... An upper low will develop within the base of a western trough on Friday. This system will progress across the Southwest toward the Four Corners/southern Rockies vicinity by Saturday morning. As this occurs, moderate mid/upper south/southwesterly flow (40-60 kt at 500 mb) will overspread the southern Rockies and adjacent High Plains. At the surface, modest boundary layer moisture will spread across southern AZ on southerly low-level flow ahead of an eastward-advancing cold front. Steepening midlevel lapse rates within the developing mid/upper low may provide weak elevated instability and isolated thunderstorms are possible. Further east, southeasterly low-level flow will transport modest Gulf moisture northwest across western Texas into eastern New Mexico along a surface trough/dryline. As the upper low/trough approaches during the afternoon into the evening, steepening midlevel lapse rates and surface dewpoints in the mid 50s F will support up to 1000 J/kg MLCAPE. Vertically veering wind profiles with around 40 kt effective shear magnitudes suggest isolated supercells will be possible with initial convection during the evening. More linear development may occur with time (toward 06z) as stronger large-scale ascent overspreads the region. Strong gusts, marginal hail and a tornado or two will be possible with this activity. ..Leitman.. 10/17/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Thu Oct 17 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible Friday night across parts of eastern New Mexico near the Sangre de Cristo and Sacramento Mountains. Some may pose a risk for small to marginally severe hail, locally damaging wind gusts, and perhaps a tornado. ...Southwest into the Southern High Plains... An upper low will develop within the base of a western trough on Friday. This system will progress across the Southwest toward the Four Corners/southern Rockies vicinity by Saturday morning. As this occurs, moderate mid/upper south/southwesterly flow (40-60 kt at 500 mb) will overspread the southern Rockies and adjacent High Plains. At the surface, modest boundary layer moisture will spread across southern AZ on southerly low-level flow ahead of an eastward-advancing cold front. Steepening midlevel lapse rates within the developing mid/upper low may provide weak elevated instability and isolated thunderstorms are possible. Further east, southeasterly low-level flow will transport modest Gulf moisture northwest across western Texas into eastern New Mexico along a surface trough/dryline. As the upper low/trough approaches during the afternoon into the evening, steepening midlevel lapse rates and surface dewpoints in the mid 50s F will support up to 1000 J/kg MLCAPE. Vertically veering wind profiles with around 40 kt effective shear magnitudes suggest isolated supercells will be possible with initial convection during the evening. More linear development may occur with time (toward 06z) as stronger large-scale ascent overspreads the region. Strong gusts, marginal hail and a tornado or two will be possible with this activity. ..Leitman.. 10/17/2024 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1206 PM CDT Thu Oct 17 2024 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE SOUTHERN HIGH PLAINS... ...SUMMARY... Strong thunderstorms are possible Friday night across parts of eastern New Mexico near the Sangre de Cristo and Sacramento Mountains. Some may pose a risk for small to marginally severe hail, locally damaging wind gusts, and perhaps a tornado. ...Southwest into the Southern High Plains... An upper low will develop within the base of a western trough on Friday. This system will progress across the Southwest toward the Four Corners/southern Rockies vicinity by Saturday morning. As this occurs, moderate mid/upper south/southwesterly flow (40-60 kt at 500 mb) will overspread the southern Rockies and adjacent High Plains. At the surface, modest boundary layer moisture will spread across southern AZ on southerly low-level flow ahead of an eastward-advancing cold front. Steepening midlevel lapse rates within the developing mid/upper low may provide weak elevated instability and isolated thunderstorms are possible. Further east, southeasterly low-level flow will transport modest Gulf moisture northwest across western Texas into eastern New Mexico along a surface trough/dryline. As the upper low/trough approaches during the afternoon into the evening, steepening midlevel lapse rates and surface dewpoints in the mid 50s F will support up to 1000 J/kg MLCAPE. Vertically veering wind profiles with around 40 kt effective shear magnitudes suggest isolated supercells will be possible with initial convection during the evening. More linear development may occur with time (toward 06z) as stronger large-scale ascent overspreads the region. Strong gusts, marginal hail and a tornado or two will be possible with this activity. ..Leitman.. 10/17/2024 Read more