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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1149 AM CDT Sat Oct 19 2024 Valid 191700Z - 201200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 10/19/2024 .PREV DISCUSSION... /ISSUED 1257 AM CDT Sat Oct 19 2024/ ...Synopsis... Localized elevated fire weather conditions are anticipated this morning through early afternoon across parts of coastal southern California. 05 UTC surface observations show a handful of stations within the higher terrain of the southern CA coast maintaining sustained 15-20 mph winds with 5-15% RH. These conditions are expected to persist through early afternoon, but will become increasingly localized. This will occur as regional gradient winds gradually abate through the day with the occlusion of the synoptic low over central AZ. However, latest ensemble guidance continues to suggest that a pocket of more persistent elevated conditions (characterized by 5-10% RH with 15-20 mph winds) will linger for several hours within the lee of the San Gabriel mountains. Further north through the Sacramento Valley, localized elevated conditions are expected this afternoon - particularly across the northwestern Valley where breezy northerly down-valley winds will support pockets of 15-20 mph with RH minimums in the teens. However, with the weakening of the regional pressure gradient, these conditions should remain fairly localized. ...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 1149 AM CDT Sat Oct 19 2024 Valid 191700Z - 201200Z No changes are needed to the D1 Fire Weather Outlook. See previous discussion below for more information. ..Thornton.. 10/19/2024 .PREV DISCUSSION... /ISSUED 1257 AM CDT Sat Oct 19 2024/ ...Synopsis... Localized elevated fire weather conditions are anticipated this morning through early afternoon across parts of coastal southern California. 05 UTC surface observations show a handful of stations within the higher terrain of the southern CA coast maintaining sustained 15-20 mph winds with 5-15% RH. These conditions are expected to persist through early afternoon, but will become increasingly localized. This will occur as regional gradient winds gradually abate through the day with the occlusion of the synoptic low over central AZ. However, latest ensemble guidance continues to suggest that a pocket of more persistent elevated conditions (characterized by 5-10% RH with 15-20 mph winds) will linger for several hours within the lee of the San Gabriel mountains. Further north through the Sacramento Valley, localized elevated conditions are expected this afternoon - particularly across the northwestern Valley where breezy northerly down-valley winds will support pockets of 15-20 mph with RH minimums in the teens. However, with the weakening of the regional pressure gradient, these conditions should remain fairly localized. ...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 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1126 AM CDT Sat Oct 19 2024 Valid 191630Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...NM into Far West TX... Morning satellite imagery shows a well-defined cyclone centered over AZ, with at least one embedded vorticity maximum rotating through its base. Expectation is for this cyclone to remain largely in place throughout the period, with the amplified upper ridging downstream persisting and the stronger westerlies remaining displaced north along the international border. Strong mid-level flow rotates cyclonically around this upper low, with enhanced mid-level southerly flow expected to continue across NM throughout the day. The southeasterly low-level flow currently ongoing across the southern High Plains/southern Plains is expected to strengthen as the gradient between the large eastern CONUS high and the lower surface pressure in the vicinity of the AZ upper cyclone tightens. This will contribute to both low-level moisture advection and strengthening deep-layer vertical shear across the southern High Plains today. Thunderstorms are already ongoing from far eastern AZ into western NM, to the west of the stationary boundary that extends from far south-central NM/ELP vicinity into northeast NM. The deep-layer flow across much of this region predominantly southerly, and with the front-parallel orientation expected to keep these storms west of the front until later this afternoon. Some heating is still possible west of the boundary, which could result in enough buoyancy for a few strong to isolated severe storms capable of damaging gusts and hail. During the afternoon and evening, the potential for more warm-sector is expected to increase, as ascent attendant to a vorticity maximum rotating through the base of the upper low spreads across the diurnally destabilized airmass over eastern NM. The combination of low-level moisture advection and modest diurnal heating will result in moderate buoyancy, with MLCAPE expected to maximize around 1000-1500 J/kg across east-central/southeast NM. A few discrete storms appear possible across southeast/south-central NM from around 20Z through 00Z or so. Vertical shear supports supercells and all severe hazards are possible with these storms, including a tornado or two. Thunderstorm coverage should increase along the front as well as it begins to slowly move eastward. A more linear mode is anticipated with this activity, but a few stronger gusts and isolated hail are still possible within this band. ..Mosier/Squitieri.. 10/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Oct 19 2024 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...Synopsis... A highly amplified mid/upper-level pattern will become less so in the northern stream through the period, as nearly zonal flow takes shape across the northern international border region, and synoptic ridging deamplifies over the eastern CONUS. A compact cyclone -- initially centered over central AZ -- will remain near its present position through the period, having become cut off temporarily from the prevailing westerlies. At the surface, 11Z analysis showed a decelerating cold to quasistationary front from a weak low over northeastern MN to another near LXN, then southwestward over northeastern KS, southeastern CO and northeastern NM near LVS, merging with a slow- moving Pacific front related more directly to the AZ cyclone. That front extended south southwestward over the Tularosa Valley to between LRU-ELP, and should move little today (with just mesobeta- scale baroclinic shifts from precip/outflow). ...Eastern NM, west TX... Along and east of the front, scattered thunderstorms are expected to develop this afternoon into evening, and congeal with time into at least a loosely contiguous band. This activity should be oriented strongly parallel to the southerly to south-southwest flow characterizing the cyclone's peripheral eastern semicircle. A few supercells are possible in the transitional time between development and quasi-linear evolution of that activity, as well as in the warm sector farther east. Some of the convective lift -- then underway from diurnal heating of a weakly capped, EML-deprived air mass -- will be aided by the upslope component of southeasterly boundary-layer flow into higher terrain across this region. The same flow also will contribute to substantial veering with height, yielding favorable deep shear (effective-shear magnitudes 35-40 kt, locally larger) for supercells in any relatively sustained/discrete convection. Hodographs should reach their largest sizes for areas with surface- based effective-inflow parcels in the 23-03Z time frame, suggesting a window of relatively maximized local tornado opportunity for any supercells that can access what should be a much higher-theta-e inflow airmass than the previous day. Surface dewpoints in the 50s F should remain common in the warm sector through the diurnal heating cycle, and low 60s already are seen in mesonet data not far upstream, over the Pecos Valley of west TX. At elevations mainly above 4000 ft, the resulting boundary-layer thermodynamic profile (including lower LCL), and slightly cooler air aloft, should steepen previously meager lapse rates enough to permit a corridor of 1000- 1500 J/kg preconvective MLCAPE. A conditional significant-hail threat may develop as well, but given the lack of greater lapse rates typically found with such hail in this area, will refrain from an unconditional sig/hatched line at this time. ..Edwards/Goss.. 10/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Oct 19 2024 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...Synopsis... A highly amplified mid/upper-level pattern will become less so in the northern stream through the period, as nearly zonal flow takes shape across the northern international border region, and synoptic ridging deamplifies over the eastern CONUS. A compact cyclone -- initially centered over central AZ -- will remain near its present position through the period, having become cut off temporarily from the prevailing westerlies. At the surface, 11Z analysis showed a decelerating cold to quasistationary front from a weak low over northeastern MN to another near LXN, then southwestward over northeastern KS, southeastern CO and northeastern NM near LVS, merging with a slow- moving Pacific front related more directly to the AZ cyclone. That front extended south southwestward over the Tularosa Valley to between LRU-ELP, and should move little today (with just mesobeta- scale baroclinic shifts from precip/outflow). ...Eastern NM, west TX... Along and east of the front, scattered thunderstorms are expected to develop this afternoon into evening, and congeal with time into at least a loosely contiguous band. This activity should be oriented strongly parallel to the southerly to south-southwest flow characterizing the cyclone's peripheral eastern semicircle. A few supercells are possible in the transitional time between development and quasi-linear evolution of that activity, as well as in the warm sector farther east. Some of the convective lift -- then underway from diurnal heating of a weakly capped, EML-deprived air mass -- will be aided by the upslope component of southeasterly boundary-layer flow into higher terrain across this region. The same flow also will contribute to substantial veering with height, yielding favorable deep shear (effective-shear magnitudes 35-40 kt, locally larger) for supercells in any relatively sustained/discrete convection. Hodographs should reach their largest sizes for areas with surface- based effective-inflow parcels in the 23-03Z time frame, suggesting a window of relatively maximized local tornado opportunity for any supercells that can access what should be a much higher-theta-e inflow airmass than the previous day. Surface dewpoints in the 50s F should remain common in the warm sector through the diurnal heating cycle, and low 60s already are seen in mesonet data not far upstream, over the Pecos Valley of west TX. At elevations mainly above 4000 ft, the resulting boundary-layer thermodynamic profile (including lower LCL), and slightly cooler air aloft, should steepen previously meager lapse rates enough to permit a corridor of 1000- 1500 J/kg preconvective MLCAPE. A conditional significant-hail threat may develop as well, but given the lack of greater lapse rates typically found with such hail in this area, will refrain from an unconditional sig/hatched line at this time. ..Edwards/Goss.. 10/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Oct 19 2024 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...Synopsis... A highly amplified mid/upper-level pattern will become less so in the northern stream through the period, as nearly zonal flow takes shape across the northern international border region, and synoptic ridging deamplifies over the eastern CONUS. A compact cyclone -- initially centered over central AZ -- will remain near its present position through the period, having become cut off temporarily from the prevailing westerlies. At the surface, 11Z analysis showed a decelerating cold to quasistationary front from a weak low over northeastern MN to another near LXN, then southwestward over northeastern KS, southeastern CO and northeastern NM near LVS, merging with a slow- moving Pacific front related more directly to the AZ cyclone. That front extended south southwestward over the Tularosa Valley to between LRU-ELP, and should move little today (with just mesobeta- scale baroclinic shifts from precip/outflow). ...Eastern NM, west TX... Along and east of the front, scattered thunderstorms are expected to develop this afternoon into evening, and congeal with time into at least a loosely contiguous band. This activity should be oriented strongly parallel to the southerly to south-southwest flow characterizing the cyclone's peripheral eastern semicircle. A few supercells are possible in the transitional time between development and quasi-linear evolution of that activity, as well as in the warm sector farther east. Some of the convective lift -- then underway from diurnal heating of a weakly capped, EML-deprived air mass -- will be aided by the upslope component of southeasterly boundary-layer flow into higher terrain across this region. The same flow also will contribute to substantial veering with height, yielding favorable deep shear (effective-shear magnitudes 35-40 kt, locally larger) for supercells in any relatively sustained/discrete convection. Hodographs should reach their largest sizes for areas with surface- based effective-inflow parcels in the 23-03Z time frame, suggesting a window of relatively maximized local tornado opportunity for any supercells that can access what should be a much higher-theta-e inflow airmass than the previous day. Surface dewpoints in the 50s F should remain common in the warm sector through the diurnal heating cycle, and low 60s already are seen in mesonet data not far upstream, over the Pecos Valley of west TX. At elevations mainly above 4000 ft, the resulting boundary-layer thermodynamic profile (including lower LCL), and slightly cooler air aloft, should steepen previously meager lapse rates enough to permit a corridor of 1000- 1500 J/kg preconvective MLCAPE. A conditional significant-hail threat may develop as well, but given the lack of greater lapse rates typically found with such hail in this area, will refrain from an unconditional sig/hatched line at this time. ..Edwards/Goss.. 10/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Oct 19 2024 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...Synopsis... A highly amplified mid/upper-level pattern will become less so in the northern stream through the period, as nearly zonal flow takes shape across the northern international border region, and synoptic ridging deamplifies over the eastern CONUS. A compact cyclone -- initially centered over central AZ -- will remain near its present position through the period, having become cut off temporarily from the prevailing westerlies. At the surface, 11Z analysis showed a decelerating cold to quasistationary front from a weak low over northeastern MN to another near LXN, then southwestward over northeastern KS, southeastern CO and northeastern NM near LVS, merging with a slow- moving Pacific front related more directly to the AZ cyclone. That front extended south southwestward over the Tularosa Valley to between LRU-ELP, and should move little today (with just mesobeta- scale baroclinic shifts from precip/outflow). ...Eastern NM, west TX... Along and east of the front, scattered thunderstorms are expected to develop this afternoon into evening, and congeal with time into at least a loosely contiguous band. This activity should be oriented strongly parallel to the southerly to south-southwest flow characterizing the cyclone's peripheral eastern semicircle. A few supercells are possible in the transitional time between development and quasi-linear evolution of that activity, as well as in the warm sector farther east. Some of the convective lift -- then underway from diurnal heating of a weakly capped, EML-deprived air mass -- will be aided by the upslope component of southeasterly boundary-layer flow into higher terrain across this region. The same flow also will contribute to substantial veering with height, yielding favorable deep shear (effective-shear magnitudes 35-40 kt, locally larger) for supercells in any relatively sustained/discrete convection. Hodographs should reach their largest sizes for areas with surface- based effective-inflow parcels in the 23-03Z time frame, suggesting a window of relatively maximized local tornado opportunity for any supercells that can access what should be a much higher-theta-e inflow airmass than the previous day. Surface dewpoints in the 50s F should remain common in the warm sector through the diurnal heating cycle, and low 60s already are seen in mesonet data not far upstream, over the Pecos Valley of west TX. At elevations mainly above 4000 ft, the resulting boundary-layer thermodynamic profile (including lower LCL), and slightly cooler air aloft, should steepen previously meager lapse rates enough to permit a corridor of 1000- 1500 J/kg preconvective MLCAPE. A conditional significant-hail threat may develop as well, but given the lack of greater lapse rates typically found with such hail in this area, will refrain from an unconditional sig/hatched line at this time. ..Edwards/Goss.. 10/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0745 AM CDT Sat Oct 19 2024 Valid 191300Z - 201200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF EASTERN NEW MEXICO AND FAR WEST TEXAS... ...SUMMARY... Large hail, severe gusts and some tornado threat are possible across eastern New Mexico and portions of far West Texas this afternoon and evening. ...Synopsis... A highly amplified mid/upper-level pattern will become less so in the northern stream through the period, as nearly zonal flow takes shape across the northern international border region, and synoptic ridging deamplifies over the eastern CONUS. A compact cyclone -- initially centered over central AZ -- will remain near its present position through the period, having become cut off temporarily from the prevailing westerlies. At the surface, 11Z analysis showed a decelerating cold to quasistationary front from a weak low over northeastern MN to another near LXN, then southwestward over northeastern KS, southeastern CO and northeastern NM near LVS, merging with a slow- moving Pacific front related more directly to the AZ cyclone. That front extended south southwestward over the Tularosa Valley to between LRU-ELP, and should move little today (with just mesobeta- scale baroclinic shifts from precip/outflow). ...Eastern NM, west TX... Along and east of the front, scattered thunderstorms are expected to develop this afternoon into evening, and congeal with time into at least a loosely contiguous band. This activity should be oriented strongly parallel to the southerly to south-southwest flow characterizing the cyclone's peripheral eastern semicircle. A few supercells are possible in the transitional time between development and quasi-linear evolution of that activity, as well as in the warm sector farther east. Some of the convective lift -- then underway from diurnal heating of a weakly capped, EML-deprived air mass -- will be aided by the upslope component of southeasterly boundary-layer flow into higher terrain across this region. The same flow also will contribute to substantial veering with height, yielding favorable deep shear (effective-shear magnitudes 35-40 kt, locally larger) for supercells in any relatively sustained/discrete convection. Hodographs should reach their largest sizes for areas with surface- based effective-inflow parcels in the 23-03Z time frame, suggesting a window of relatively maximized local tornado opportunity for any supercells that can access what should be a much higher-theta-e inflow airmass than the previous day. Surface dewpoints in the 50s F should remain common in the warm sector through the diurnal heating cycle, and low 60s already are seen in mesonet data not far upstream, over the Pecos Valley of west TX. At elevations mainly above 4000 ft, the resulting boundary-layer thermodynamic profile (including lower LCL), and slightly cooler air aloft, should steepen previously meager lapse rates enough to permit a corridor of 1000- 1500 J/kg preconvective MLCAPE. A conditional significant-hail threat may develop as well, but given the lack of greater lapse rates typically found with such hail in this area, will refrain from an unconditional sig/hatched line at this time. ..Edwards/Goss.. 10/19/2024 Read more

000
ABPZ20 KNHC 191132
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Sat Oct 19 2024

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

South of Southwestern Mexico:
After Nadine dissipates over southern Mexico, its remnants are
expected to move into the eastern Pacific. The combination of the
remnants of Nadine and influences from the Gulf of Tehuantepec gap
wind event are forecast to result in formation of a new low pressure
system off the coast of southwestern Mexico in a couple of days.
Additional development is expected after that time, and a tropical
depression is likely to form during the early to middle part of next
week while the system moves westward at about 15 mph away from the
coast of Mexico.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...high...80 percent.

$$
Forecaster Cangialosi

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sat Oct 19 2024 Valid 221200Z - 271200Z ...DISCUSSION... A shortwave trough is expected to move into the Midwest before phasing with a broader upper-level trough in the Great Lakes region by the middle of next week. Access to Gulf moisture will become more restricted as this feature moves eastward. Across parts of the West and Plains, an upper-level ridge will develop and shift east through the remainder of the week into the weekend. The upper-level pattern becomes less certain during the weekend, but at least a brief period of quasi-zonal flow aloft is currently expected. With another cold-frontal intrusion into the Gulf expected to occur late this week, moisture availability/quality for any shortwave troughs moving through the westerlies is highly uncertain. Severe weather potential continues to appear low through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sat Oct 19 2024 Valid 221200Z - 271200Z ...DISCUSSION... A shortwave trough is expected to move into the Midwest before phasing with a broader upper-level trough in the Great Lakes region by the middle of next week. Access to Gulf moisture will become more restricted as this feature moves eastward. Across parts of the West and Plains, an upper-level ridge will develop and shift east through the remainder of the week into the weekend. The upper-level pattern becomes less certain during the weekend, but at least a brief period of quasi-zonal flow aloft is currently expected. With another cold-frontal intrusion into the Gulf expected to occur late this week, moisture availability/quality for any shortwave troughs moving through the westerlies is highly uncertain. Severe weather potential continues to appear low through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sat Oct 19 2024 Valid 221200Z - 271200Z ...DISCUSSION... A shortwave trough is expected to move into the Midwest before phasing with a broader upper-level trough in the Great Lakes region by the middle of next week. Access to Gulf moisture will become more restricted as this feature moves eastward. Across parts of the West and Plains, an upper-level ridge will develop and shift east through the remainder of the week into the weekend. The upper-level pattern becomes less certain during the weekend, but at least a brief period of quasi-zonal flow aloft is currently expected. With another cold-frontal intrusion into the Gulf expected to occur late this week, moisture availability/quality for any shortwave troughs moving through the westerlies is highly uncertain. Severe weather potential continues to appear low through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sat Oct 19 2024 Valid 221200Z - 271200Z ...DISCUSSION... A shortwave trough is expected to move into the Midwest before phasing with a broader upper-level trough in the Great Lakes region by the middle of next week. Access to Gulf moisture will become more restricted as this feature moves eastward. Across parts of the West and Plains, an upper-level ridge will develop and shift east through the remainder of the week into the weekend. The upper-level pattern becomes less certain during the weekend, but at least a brief period of quasi-zonal flow aloft is currently expected. With another cold-frontal intrusion into the Gulf expected to occur late this week, moisture availability/quality for any shortwave troughs moving through the westerlies is highly uncertain. Severe weather potential continues to appear low through next weekend. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0348 AM CDT Sat Oct 19 2024 Valid 221200Z - 271200Z ...DISCUSSION... A shortwave trough is expected to move into the Midwest before phasing with a broader upper-level trough in the Great Lakes region by the middle of next week. Access to Gulf moisture will become more restricted as this feature moves eastward. Across parts of the West and Plains, an upper-level ridge will develop and shift east through the remainder of the week into the weekend. The upper-level pattern becomes less certain during the weekend, but at least a brief period of quasi-zonal flow aloft is currently expected. With another cold-frontal intrusion into the Gulf expected to occur late this week, moisture availability/quality for any shortwave troughs moving through the westerlies is highly uncertain. Severe weather potential continues to appear low through next weekend. Read more