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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central and northeastern Oklahoma this evening and overnight. The strongest of these storms may produce marginally severe hail. ...Synopsis... In the mid levels, a lead shortwave trough over the Rockies will move eastward over the southern Plains early this morning ahead of a second subtle wave across central NM. At the same time, a much stronger trough and 80-90 kt mid-level jet are forecast to dig southeastward over the Four Corners, while shortwave ridging intensifies over the central CONUS. The lead shortwave should merge with the approaching secondary trough, rapidly amplifying the general flow pattern over the western third of the CONUS. Strong mid-level flow spilling over the Rockies will aid in lee cyclogenesis, with a 1000-1004 mb cyclone expected to develop over parts of central OK by this evening. Intensifying surface wind fields ahead of the deepening trough will draw modest moisture northward across parts of TX and southern OK this evening. The upper trough will begin to move eastward and intensify further into a closed low over the southern Plains late tonight into early Monday. ...Central and northeastern Oklahoma... As the first in a series of shortwave troughs passes over the southern Plains early this morning, low-level warm advection is forecast to intensify ahead of the lee low and developing dryline/ surface trough. Northward advection of the modestly moist surface air mass over western/central TX and southern OK will intensify, with widespread showers and isolated embedded thunderstorms across the southern Plains likely to start the forecast period. Sustained isotropic ascent is also expected to bring widespread cloud cover limiting diurnal heating and available buoyancy for much of the day. Elevated convection should gradually expand northward across KS and the central Plains through the day as the lead shortwave and ascent lift north with it. Stronger height falls aloft, increasing differential thermal advection and the subsequent development of weak buoyancy is expected later this evening and through the overnight hours as the main shortwave trough begins to eject eastward. -20C 500 mb temps should support steepening lapse rates of 7-8 C/km sufficient for approximately 500-750 J/kg of MUCAPE over OK. Elevated atop a sizable surface inversion, isolated thunderstorms are possible over parts of central and eastern OK after 00z continuing through the overnight hours. 50-60 kt of mid-level flow and elongated hodographs may support brief organization into transient supercell structures or clusters. Isolated hail, some of which may be marginally severe, is possible over central and eastern OK immediately ahead of the cold core aloft where buoyancy is expected to be the largest. Confidence in storm coverage and organization however is very low owing to the paltry buoyancy, limited moisture depth and poor diurnal phasing of the upper-level trough. ..Lyons/Jewell.. 11/19/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central and northeastern Oklahoma this evening and overnight. The strongest of these storms may produce marginally severe hail. ...Synopsis... In the mid levels, a lead shortwave trough over the Rockies will move eastward over the southern Plains early this morning ahead of a second subtle wave across central NM. At the same time, a much stronger trough and 80-90 kt mid-level jet are forecast to dig southeastward over the Four Corners, while shortwave ridging intensifies over the central CONUS. The lead shortwave should merge with the approaching secondary trough, rapidly amplifying the general flow pattern over the western third of the CONUS. Strong mid-level flow spilling over the Rockies will aid in lee cyclogenesis, with a 1000-1004 mb cyclone expected to develop over parts of central OK by this evening. Intensifying surface wind fields ahead of the deepening trough will draw modest moisture northward across parts of TX and southern OK this evening. The upper trough will begin to move eastward and intensify further into a closed low over the southern Plains late tonight into early Monday. ...Central and northeastern Oklahoma... As the first in a series of shortwave troughs passes over the southern Plains early this morning, low-level warm advection is forecast to intensify ahead of the lee low and developing dryline/ surface trough. Northward advection of the modestly moist surface air mass over western/central TX and southern OK will intensify, with widespread showers and isolated embedded thunderstorms across the southern Plains likely to start the forecast period. Sustained isotropic ascent is also expected to bring widespread cloud cover limiting diurnal heating and available buoyancy for much of the day. Elevated convection should gradually expand northward across KS and the central Plains through the day as the lead shortwave and ascent lift north with it. Stronger height falls aloft, increasing differential thermal advection and the subsequent development of weak buoyancy is expected later this evening and through the overnight hours as the main shortwave trough begins to eject eastward. -20C 500 mb temps should support steepening lapse rates of 7-8 C/km sufficient for approximately 500-750 J/kg of MUCAPE over OK. Elevated atop a sizable surface inversion, isolated thunderstorms are possible over parts of central and eastern OK after 00z continuing through the overnight hours. 50-60 kt of mid-level flow and elongated hodographs may support brief organization into transient supercell structures or clusters. Isolated hail, some of which may be marginally severe, is possible over central and eastern OK immediately ahead of the cold core aloft where buoyancy is expected to be the largest. Confidence in storm coverage and organization however is very low owing to the paltry buoyancy, limited moisture depth and poor diurnal phasing of the upper-level trough. ..Lyons/Jewell.. 11/19/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central and northeastern Oklahoma this evening and overnight. The strongest of these storms may produce marginally severe hail. ...Synopsis... In the mid levels, a lead shortwave trough over the Rockies will move eastward over the southern Plains early this morning ahead of a second subtle wave across central NM. At the same time, a much stronger trough and 80-90 kt mid-level jet are forecast to dig southeastward over the Four Corners, while shortwave ridging intensifies over the central CONUS. The lead shortwave should merge with the approaching secondary trough, rapidly amplifying the general flow pattern over the western third of the CONUS. Strong mid-level flow spilling over the Rockies will aid in lee cyclogenesis, with a 1000-1004 mb cyclone expected to develop over parts of central OK by this evening. Intensifying surface wind fields ahead of the deepening trough will draw modest moisture northward across parts of TX and southern OK this evening. The upper trough will begin to move eastward and intensify further into a closed low over the southern Plains late tonight into early Monday. ...Central and northeastern Oklahoma... As the first in a series of shortwave troughs passes over the southern Plains early this morning, low-level warm advection is forecast to intensify ahead of the lee low and developing dryline/ surface trough. Northward advection of the modestly moist surface air mass over western/central TX and southern OK will intensify, with widespread showers and isolated embedded thunderstorms across the southern Plains likely to start the forecast period. Sustained isotropic ascent is also expected to bring widespread cloud cover limiting diurnal heating and available buoyancy for much of the day. Elevated convection should gradually expand northward across KS and the central Plains through the day as the lead shortwave and ascent lift north with it. Stronger height falls aloft, increasing differential thermal advection and the subsequent development of weak buoyancy is expected later this evening and through the overnight hours as the main shortwave trough begins to eject eastward. -20C 500 mb temps should support steepening lapse rates of 7-8 C/km sufficient for approximately 500-750 J/kg of MUCAPE over OK. Elevated atop a sizable surface inversion, isolated thunderstorms are possible over parts of central and eastern OK after 00z continuing through the overnight hours. 50-60 kt of mid-level flow and elongated hodographs may support brief organization into transient supercell structures or clusters. Isolated hail, some of which may be marginally severe, is possible over central and eastern OK immediately ahead of the cold core aloft where buoyancy is expected to be the largest. Confidence in storm coverage and organization however is very low owing to the paltry buoyancy, limited moisture depth and poor diurnal phasing of the upper-level trough. ..Lyons/Jewell.. 11/19/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central and northeastern Oklahoma this evening and overnight. The strongest of these storms may produce marginally severe hail. ...Synopsis... In the mid levels, a lead shortwave trough over the Rockies will move eastward over the southern Plains early this morning ahead of a second subtle wave across central NM. At the same time, a much stronger trough and 80-90 kt mid-level jet are forecast to dig southeastward over the Four Corners, while shortwave ridging intensifies over the central CONUS. The lead shortwave should merge with the approaching secondary trough, rapidly amplifying the general flow pattern over the western third of the CONUS. Strong mid-level flow spilling over the Rockies will aid in lee cyclogenesis, with a 1000-1004 mb cyclone expected to develop over parts of central OK by this evening. Intensifying surface wind fields ahead of the deepening trough will draw modest moisture northward across parts of TX and southern OK this evening. The upper trough will begin to move eastward and intensify further into a closed low over the southern Plains late tonight into early Monday. ...Central and northeastern Oklahoma... As the first in a series of shortwave troughs passes over the southern Plains early this morning, low-level warm advection is forecast to intensify ahead of the lee low and developing dryline/ surface trough. Northward advection of the modestly moist surface air mass over western/central TX and southern OK will intensify, with widespread showers and isolated embedded thunderstorms across the southern Plains likely to start the forecast period. Sustained isotropic ascent is also expected to bring widespread cloud cover limiting diurnal heating and available buoyancy for much of the day. Elevated convection should gradually expand northward across KS and the central Plains through the day as the lead shortwave and ascent lift north with it. Stronger height falls aloft, increasing differential thermal advection and the subsequent development of weak buoyancy is expected later this evening and through the overnight hours as the main shortwave trough begins to eject eastward. -20C 500 mb temps should support steepening lapse rates of 7-8 C/km sufficient for approximately 500-750 J/kg of MUCAPE over OK. Elevated atop a sizable surface inversion, isolated thunderstorms are possible over parts of central and eastern OK after 00z continuing through the overnight hours. 50-60 kt of mid-level flow and elongated hodographs may support brief organization into transient supercell structures or clusters. Isolated hail, some of which may be marginally severe, is possible over central and eastern OK immediately ahead of the cold core aloft where buoyancy is expected to be the largest. Confidence in storm coverage and organization however is very low owing to the paltry buoyancy, limited moisture depth and poor diurnal phasing of the upper-level trough. ..Lyons/Jewell.. 11/19/2023 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1155 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS OVER PARTS OF CENTRAL AND NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central and northeastern Oklahoma this evening and overnight. The strongest of these storms may produce marginally severe hail. ...Synopsis... In the mid levels, a lead shortwave trough over the Rockies will move eastward over the southern Plains early this morning ahead of a second subtle wave across central NM. At the same time, a much stronger trough and 80-90 kt mid-level jet are forecast to dig southeastward over the Four Corners, while shortwave ridging intensifies over the central CONUS. The lead shortwave should merge with the approaching secondary trough, rapidly amplifying the general flow pattern over the western third of the CONUS. Strong mid-level flow spilling over the Rockies will aid in lee cyclogenesis, with a 1000-1004 mb cyclone expected to develop over parts of central OK by this evening. Intensifying surface wind fields ahead of the deepening trough will draw modest moisture northward across parts of TX and southern OK this evening. The upper trough will begin to move eastward and intensify further into a closed low over the southern Plains late tonight into early Monday. ...Central and northeastern Oklahoma... As the first in a series of shortwave troughs passes over the southern Plains early this morning, low-level warm advection is forecast to intensify ahead of the lee low and developing dryline/ surface trough. Northward advection of the modestly moist surface air mass over western/central TX and southern OK will intensify, with widespread showers and isolated embedded thunderstorms across the southern Plains likely to start the forecast period. Sustained isotropic ascent is also expected to bring widespread cloud cover limiting diurnal heating and available buoyancy for much of the day. Elevated convection should gradually expand northward across KS and the central Plains through the day as the lead shortwave and ascent lift north with it. Stronger height falls aloft, increasing differential thermal advection and the subsequent development of weak buoyancy is expected later this evening and through the overnight hours as the main shortwave trough begins to eject eastward. -20C 500 mb temps should support steepening lapse rates of 7-8 C/km sufficient for approximately 500-750 J/kg of MUCAPE over OK. Elevated atop a sizable surface inversion, isolated thunderstorms are possible over parts of central and eastern OK after 00z continuing through the overnight hours. 50-60 kt of mid-level flow and elongated hodographs may support brief organization into transient supercell structures or clusters. Isolated hail, some of which may be marginally severe, is possible over central and eastern OK immediately ahead of the cold core aloft where buoyancy is expected to be the largest. Confidence in storm coverage and organization however is very low owing to the paltry buoyancy, limited moisture depth and poor diurnal phasing of the upper-level trough. ..Lyons/Jewell.. 11/19/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0613 PM CST Sat Nov 18 2023 Valid 190100Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Discussion... A large scale upper trough over the West will be the primary focus for a few thunderstorms through tonight, with a lead wave moving from NM into the southern Plains, and a strong feature into the Great Basin. Isolated convection now over NM is expected to increase in coverage late tonight from the TX Panhandle into parts of KS and OK, where elevated CAPE up to 500 J/kg is forecast. This elevated destabilization and lift will be aided by cooling aloft and increasing theta-e advection around 700 mb. Severe hail is not anticipated given weak CAPE values, despite favorable deep-layer shear to sustain a few cells. Elsewhere, large-scale ascent will increase into the Great Basin overnight with cooling aloft and a cold front pushing across NV and toward western UT. MUCAPE on the order of 50-250 J/kg may yield sporadic lightning flashes. ..Jewell.. 11/19/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0613 PM CST Sat Nov 18 2023 Valid 190100Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Discussion... A large scale upper trough over the West will be the primary focus for a few thunderstorms through tonight, with a lead wave moving from NM into the southern Plains, and a strong feature into the Great Basin. Isolated convection now over NM is expected to increase in coverage late tonight from the TX Panhandle into parts of KS and OK, where elevated CAPE up to 500 J/kg is forecast. This elevated destabilization and lift will be aided by cooling aloft and increasing theta-e advection around 700 mb. Severe hail is not anticipated given weak CAPE values, despite favorable deep-layer shear to sustain a few cells. Elsewhere, large-scale ascent will increase into the Great Basin overnight with cooling aloft and a cold front pushing across NV and toward western UT. MUCAPE on the order of 50-250 J/kg may yield sporadic lightning flashes. ..Jewell.. 11/19/2023 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0613 PM CST Sat Nov 18 2023 Valid 190100Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are unlikely through tonight. ...Discussion... A large scale upper trough over the West will be the primary focus for a few thunderstorms through tonight, with a lead wave moving from NM into the southern Plains, and a strong feature into the Great Basin. Isolated convection now over NM is expected to increase in coverage late tonight from the TX Panhandle into parts of KS and OK, where elevated CAPE up to 500 J/kg is forecast. This elevated destabilization and lift will be aided by cooling aloft and increasing theta-e advection around 700 mb. Severe hail is not anticipated given weak CAPE values, despite favorable deep-layer shear to sustain a few cells. Elsewhere, large-scale ascent will increase into the Great Basin overnight with cooling aloft and a cold front pushing across NV and toward western UT. MUCAPE on the order of 50-250 J/kg may yield sporadic lightning flashes. ..Jewell.. 11/19/2023 Read more

No watches are valid as of Sat Nov 18 22:27:01 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Nov 18 22:27:01 UTC 2023.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sat Nov 18 2023 Valid 201200Z - 261200Z A broad, strong upper-level trough will be moving through the southern Plains and into the Southeast on Monday. This trough will continue eastward through the middle portions of the coming week. In its wake, short-term upper-level ridging will amplify in the West before being broken down by the next upper-level trough. This second trough is forecast to dig southward along the West Coast and eventually eject into the southern Plains by late next week. Thereafter, models suggest broad troughing across much of the CONUS. At the surface, a cold front will move into the southern Plains Monday/Tuesday. Another surface low/cold front will impact the southern Plains as the second trough moves through late next week into the weekend. There is some possibility of surface high pressure building into the West next weekend. ...Central/Southern Plains... There is some potential for dry and windy conditions behind the initial cold front Monday and Tuesday. With the potential for precipitation and the cooler temperatures expected, fire weather concerns will likely remain low to perhaps locally elevated. Additional dry and windy conditions are possible in the southern High Plains as the second trough ejects into the region. Model signals for precipitation in this area are weaker. Depending on fuel response in the coming days, some elevated concerns could develop on Thursday. With temperatures predicted to be colder with the second front, post-frontal fire weather concerns are not expected. ...Southern California... Moderate to strong offshore winds will subside Tuesday into Wednesday. Additional offshore winds could occur by next weekend. At present, offshore gradients appear to be weaker as is upper-level wind support. Uncertainty in critical fire weather is medium to high, but model trends and fuel status will continue to be monitored. ..Wendt.. 11/18/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sat Nov 18 2023 Valid 201200Z - 261200Z A broad, strong upper-level trough will be moving through the southern Plains and into the Southeast on Monday. This trough will continue eastward through the middle portions of the coming week. In its wake, short-term upper-level ridging will amplify in the West before being broken down by the next upper-level trough. This second trough is forecast to dig southward along the West Coast and eventually eject into the southern Plains by late next week. Thereafter, models suggest broad troughing across much of the CONUS. At the surface, a cold front will move into the southern Plains Monday/Tuesday. Another surface low/cold front will impact the southern Plains as the second trough moves through late next week into the weekend. There is some possibility of surface high pressure building into the West next weekend. ...Central/Southern Plains... There is some potential for dry and windy conditions behind the initial cold front Monday and Tuesday. With the potential for precipitation and the cooler temperatures expected, fire weather concerns will likely remain low to perhaps locally elevated. Additional dry and windy conditions are possible in the southern High Plains as the second trough ejects into the region. Model signals for precipitation in this area are weaker. Depending on fuel response in the coming days, some elevated concerns could develop on Thursday. With temperatures predicted to be colder with the second front, post-frontal fire weather concerns are not expected. ...Southern California... Moderate to strong offshore winds will subside Tuesday into Wednesday. Additional offshore winds could occur by next weekend. At present, offshore gradients appear to be weaker as is upper-level wind support. Uncertainty in critical fire weather is medium to high, but model trends and fuel status will continue to be monitored. ..Wendt.. 11/18/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sat Nov 18 2023 Valid 201200Z - 261200Z A broad, strong upper-level trough will be moving through the southern Plains and into the Southeast on Monday. This trough will continue eastward through the middle portions of the coming week. In its wake, short-term upper-level ridging will amplify in the West before being broken down by the next upper-level trough. This second trough is forecast to dig southward along the West Coast and eventually eject into the southern Plains by late next week. Thereafter, models suggest broad troughing across much of the CONUS. At the surface, a cold front will move into the southern Plains Monday/Tuesday. Another surface low/cold front will impact the southern Plains as the second trough moves through late next week into the weekend. There is some possibility of surface high pressure building into the West next weekend. ...Central/Southern Plains... There is some potential for dry and windy conditions behind the initial cold front Monday and Tuesday. With the potential for precipitation and the cooler temperatures expected, fire weather concerns will likely remain low to perhaps locally elevated. Additional dry and windy conditions are possible in the southern High Plains as the second trough ejects into the region. Model signals for precipitation in this area are weaker. Depending on fuel response in the coming days, some elevated concerns could develop on Thursday. With temperatures predicted to be colder with the second front, post-frontal fire weather concerns are not expected. ...Southern California... Moderate to strong offshore winds will subside Tuesday into Wednesday. Additional offshore winds could occur by next weekend. At present, offshore gradients appear to be weaker as is upper-level wind support. Uncertainty in critical fire weather is medium to high, but model trends and fuel status will continue to be monitored. ..Wendt.. 11/18/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sat Nov 18 2023 Valid 201200Z - 261200Z A broad, strong upper-level trough will be moving through the southern Plains and into the Southeast on Monday. This trough will continue eastward through the middle portions of the coming week. In its wake, short-term upper-level ridging will amplify in the West before being broken down by the next upper-level trough. This second trough is forecast to dig southward along the West Coast and eventually eject into the southern Plains by late next week. Thereafter, models suggest broad troughing across much of the CONUS. At the surface, a cold front will move into the southern Plains Monday/Tuesday. Another surface low/cold front will impact the southern Plains as the second trough moves through late next week into the weekend. There is some possibility of surface high pressure building into the West next weekend. ...Central/Southern Plains... There is some potential for dry and windy conditions behind the initial cold front Monday and Tuesday. With the potential for precipitation and the cooler temperatures expected, fire weather concerns will likely remain low to perhaps locally elevated. Additional dry and windy conditions are possible in the southern High Plains as the second trough ejects into the region. Model signals for precipitation in this area are weaker. Depending on fuel response in the coming days, some elevated concerns could develop on Thursday. With temperatures predicted to be colder with the second front, post-frontal fire weather concerns are not expected. ...Southern California... Moderate to strong offshore winds will subside Tuesday into Wednesday. Additional offshore winds could occur by next weekend. At present, offshore gradients appear to be weaker as is upper-level wind support. Uncertainty in critical fire weather is medium to high, but model trends and fuel status will continue to be monitored. ..Wendt.. 11/18/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0336 PM CST Sat Nov 18 2023 Valid 201200Z - 261200Z A broad, strong upper-level trough will be moving through the southern Plains and into the Southeast on Monday. This trough will continue eastward through the middle portions of the coming week. In its wake, short-term upper-level ridging will amplify in the West before being broken down by the next upper-level trough. This second trough is forecast to dig southward along the West Coast and eventually eject into the southern Plains by late next week. Thereafter, models suggest broad troughing across much of the CONUS. At the surface, a cold front will move into the southern Plains Monday/Tuesday. Another surface low/cold front will impact the southern Plains as the second trough moves through late next week into the weekend. There is some possibility of surface high pressure building into the West next weekend. ...Central/Southern Plains... There is some potential for dry and windy conditions behind the initial cold front Monday and Tuesday. With the potential for precipitation and the cooler temperatures expected, fire weather concerns will likely remain low to perhaps locally elevated. Additional dry and windy conditions are possible in the southern High Plains as the second trough ejects into the region. Model signals for precipitation in this area are weaker. Depending on fuel response in the coming days, some elevated concerns could develop on Thursday. With temperatures predicted to be colder with the second front, post-frontal fire weather concerns are not expected. ...Southern California... Moderate to strong offshore winds will subside Tuesday into Wednesday. Additional offshore winds could occur by next weekend. At present, offshore gradients appear to be weaker as is upper-level wind support. Uncertainty in critical fire weather is medium to high, but model trends and fuel status will continue to be monitored. ..Wendt.. 11/18/2023 ...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 0148 PM CST Sat Nov 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...20Z Update... The categorical (10 percent probability) thunderstorm line has been adjusted, mostly to account for the progression of synoptic features. Across California, in the wake of one short wave trough progressing across and east of the northern Sierra Nevada, weak mid-level warm advection is ongoing across much of the Sacramento/San Joaquin Valleys. While increasing breaks in the overcast may allow for boundary-layer warming to contribute to weak destabilization, orographic ascent, associated with an increasingly upslope component along the western slopes of the Sierra Nevada, appears the most prominent potential forcing for any thunderstorm development. Otherwise, increasing low-level convergence across the northern Sacramento Valley vicinity might provide another focus for thunderstorm development, mainly after 00-02Z, as mid-level forcing for ascent and cooling (within the exit region of a 100+ kt 500 mb jet) spread inland near and north/northeast of Eureka. ..Kerr.. 11/18/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Nov 18 2023/ ...Discussion... Aside from the potential for a lightning flash or two near (but primarily off) the eastern Florida coast, greater lightning coverage will remain confined to southwestern and, later, south-central portions of the country. This convection will be associated with the continued advance/evolution of large-scale upper troughing across the western half of the country (and, downstream, the associated low-level warm advection that will occur later in the period in tandem with low-level jet development over western portions of the Plains). Beneath the trough during the afternoon, low-level and deep-layer wind profiles across the Central Valley of California will remain conditionally supportive of organized convection. However, widespread cloud cover persists across the area, which should remain the case through the afternoon, when low-level shear will become maximized (followed by a weakening into the early evening hours). As such, destabilization potential will remain minimal -- which is supported by new/12Z model guidance showing minimal buoyancy at best. Thus, any potential for a brief tornado appears too low to include in an areal outlook. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Sat Nov 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...20Z Update... The categorical (10 percent probability) thunderstorm line has been adjusted, mostly to account for the progression of synoptic features. Across California, in the wake of one short wave trough progressing across and east of the northern Sierra Nevada, weak mid-level warm advection is ongoing across much of the Sacramento/San Joaquin Valleys. While increasing breaks in the overcast may allow for boundary-layer warming to contribute to weak destabilization, orographic ascent, associated with an increasingly upslope component along the western slopes of the Sierra Nevada, appears the most prominent potential forcing for any thunderstorm development. Otherwise, increasing low-level convergence across the northern Sacramento Valley vicinity might provide another focus for thunderstorm development, mainly after 00-02Z, as mid-level forcing for ascent and cooling (within the exit region of a 100+ kt 500 mb jet) spread inland near and north/northeast of Eureka. ..Kerr.. 11/18/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Nov 18 2023/ ...Discussion... Aside from the potential for a lightning flash or two near (but primarily off) the eastern Florida coast, greater lightning coverage will remain confined to southwestern and, later, south-central portions of the country. This convection will be associated with the continued advance/evolution of large-scale upper troughing across the western half of the country (and, downstream, the associated low-level warm advection that will occur later in the period in tandem with low-level jet development over western portions of the Plains). Beneath the trough during the afternoon, low-level and deep-layer wind profiles across the Central Valley of California will remain conditionally supportive of organized convection. However, widespread cloud cover persists across the area, which should remain the case through the afternoon, when low-level shear will become maximized (followed by a weakening into the early evening hours). As such, destabilization potential will remain minimal -- which is supported by new/12Z model guidance showing minimal buoyancy at best. Thus, any potential for a brief tornado appears too low to include in an areal outlook. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Sat Nov 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...20Z Update... The categorical (10 percent probability) thunderstorm line has been adjusted, mostly to account for the progression of synoptic features. Across California, in the wake of one short wave trough progressing across and east of the northern Sierra Nevada, weak mid-level warm advection is ongoing across much of the Sacramento/San Joaquin Valleys. While increasing breaks in the overcast may allow for boundary-layer warming to contribute to weak destabilization, orographic ascent, associated with an increasingly upslope component along the western slopes of the Sierra Nevada, appears the most prominent potential forcing for any thunderstorm development. Otherwise, increasing low-level convergence across the northern Sacramento Valley vicinity might provide another focus for thunderstorm development, mainly after 00-02Z, as mid-level forcing for ascent and cooling (within the exit region of a 100+ kt 500 mb jet) spread inland near and north/northeast of Eureka. ..Kerr.. 11/18/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Nov 18 2023/ ...Discussion... Aside from the potential for a lightning flash or two near (but primarily off) the eastern Florida coast, greater lightning coverage will remain confined to southwestern and, later, south-central portions of the country. This convection will be associated with the continued advance/evolution of large-scale upper troughing across the western half of the country (and, downstream, the associated low-level warm advection that will occur later in the period in tandem with low-level jet development over western portions of the Plains). Beneath the trough during the afternoon, low-level and deep-layer wind profiles across the Central Valley of California will remain conditionally supportive of organized convection. However, widespread cloud cover persists across the area, which should remain the case through the afternoon, when low-level shear will become maximized (followed by a weakening into the early evening hours). As such, destabilization potential will remain minimal -- which is supported by new/12Z model guidance showing minimal buoyancy at best. Thus, any potential for a brief tornado appears too low to include in an areal outlook. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Sat Nov 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...20Z Update... The categorical (10 percent probability) thunderstorm line has been adjusted, mostly to account for the progression of synoptic features. Across California, in the wake of one short wave trough progressing across and east of the northern Sierra Nevada, weak mid-level warm advection is ongoing across much of the Sacramento/San Joaquin Valleys. While increasing breaks in the overcast may allow for boundary-layer warming to contribute to weak destabilization, orographic ascent, associated with an increasingly upslope component along the western slopes of the Sierra Nevada, appears the most prominent potential forcing for any thunderstorm development. Otherwise, increasing low-level convergence across the northern Sacramento Valley vicinity might provide another focus for thunderstorm development, mainly after 00-02Z, as mid-level forcing for ascent and cooling (within the exit region of a 100+ kt 500 mb jet) spread inland near and north/northeast of Eureka. ..Kerr.. 11/18/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Nov 18 2023/ ...Discussion... Aside from the potential for a lightning flash or two near (but primarily off) the eastern Florida coast, greater lightning coverage will remain confined to southwestern and, later, south-central portions of the country. This convection will be associated with the continued advance/evolution of large-scale upper troughing across the western half of the country (and, downstream, the associated low-level warm advection that will occur later in the period in tandem with low-level jet development over western portions of the Plains). Beneath the trough during the afternoon, low-level and deep-layer wind profiles across the Central Valley of California will remain conditionally supportive of organized convection. However, widespread cloud cover persists across the area, which should remain the case through the afternoon, when low-level shear will become maximized (followed by a weakening into the early evening hours). As such, destabilization potential will remain minimal -- which is supported by new/12Z model guidance showing minimal buoyancy at best. Thus, any potential for a brief tornado appears too low to include in an areal outlook. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0148 PM CST Sat Nov 18 2023 Valid 182000Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...20Z Update... The categorical (10 percent probability) thunderstorm line has been adjusted, mostly to account for the progression of synoptic features. Across California, in the wake of one short wave trough progressing across and east of the northern Sierra Nevada, weak mid-level warm advection is ongoing across much of the Sacramento/San Joaquin Valleys. While increasing breaks in the overcast may allow for boundary-layer warming to contribute to weak destabilization, orographic ascent, associated with an increasingly upslope component along the western slopes of the Sierra Nevada, appears the most prominent potential forcing for any thunderstorm development. Otherwise, increasing low-level convergence across the northern Sacramento Valley vicinity might provide another focus for thunderstorm development, mainly after 00-02Z, as mid-level forcing for ascent and cooling (within the exit region of a 100+ kt 500 mb jet) spread inland near and north/northeast of Eureka. ..Kerr.. 11/18/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Sat Nov 18 2023/ ...Discussion... Aside from the potential for a lightning flash or two near (but primarily off) the eastern Florida coast, greater lightning coverage will remain confined to southwestern and, later, south-central portions of the country. This convection will be associated with the continued advance/evolution of large-scale upper troughing across the western half of the country (and, downstream, the associated low-level warm advection that will occur later in the period in tandem with low-level jet development over western portions of the Plains). Beneath the trough during the afternoon, low-level and deep-layer wind profiles across the Central Valley of California will remain conditionally supportive of organized convection. However, widespread cloud cover persists across the area, which should remain the case through the afternoon, when low-level shear will become maximized (followed by a weakening into the early evening hours). As such, destabilization potential will remain minimal -- which is supported by new/12Z model guidance showing minimal buoyancy at best. Thus, any potential for a brief tornado appears too low to include in an areal outlook. Read more