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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 Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. Dry and windy conditions in southern California will be on the increase very late Sunday into Monday morning. Given the current state of fuels and potential for rainfall today and tonight, fire weather concerns should remain low on Sunday. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CST Sat Nov 18 2023/ ...Synopsis... A progressive mid-level flow pattern is expected to persist D2/Sunday as an upper trough over the East Coast continues to move offshore. A broad western US trough is expected to amplify through the weekend before ejecting eastward into the central US by the end of the forecast period. Transient surface high pressure will persist over the eastern third of the country in the wake of an earlier cold front. Cooler and drier conditions are possible over parts of the central and southern Appalachians. Occasional gusty winds near the higher terrain may support brief elevated fire-weather conditions within areas of dry fuels across NC and VA. Localized dry and breezy conditions are also possible over parts of eastern NM. However, with only transient overlap of dry and breezy conditions, widespread fire-weather concerns appear low for much of the CONUS. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. Dry and windy conditions in southern California will be on the increase very late Sunday into Monday morning. Given the current state of fuels and potential for rainfall today and tonight, fire weather concerns should remain low on Sunday. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CST Sat Nov 18 2023/ ...Synopsis... A progressive mid-level flow pattern is expected to persist D2/Sunday as an upper trough over the East Coast continues to move offshore. A broad western US trough is expected to amplify through the weekend before ejecting eastward into the central US by the end of the forecast period. Transient surface high pressure will persist over the eastern third of the country in the wake of an earlier cold front. Cooler and drier conditions are possible over parts of the central and southern Appalachians. Occasional gusty winds near the higher terrain may support brief elevated fire-weather conditions within areas of dry fuels across NC and VA. Localized dry and breezy conditions are also possible over parts of eastern NM. However, with only transient overlap of dry and breezy conditions, widespread fire-weather concerns appear low for much of the CONUS. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. Dry and windy conditions in southern California will be on the increase very late Sunday into Monday morning. Given the current state of fuels and potential for rainfall today and tonight, fire weather concerns should remain low on Sunday. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CST Sat Nov 18 2023/ ...Synopsis... A progressive mid-level flow pattern is expected to persist D2/Sunday as an upper trough over the East Coast continues to move offshore. A broad western US trough is expected to amplify through the weekend before ejecting eastward into the central US by the end of the forecast period. Transient surface high pressure will persist over the eastern third of the country in the wake of an earlier cold front. Cooler and drier conditions are possible over parts of the central and southern Appalachians. Occasional gusty winds near the higher terrain may support brief elevated fire-weather conditions within areas of dry fuels across NC and VA. Localized dry and breezy conditions are also possible over parts of eastern NM. However, with only transient overlap of dry and breezy conditions, widespread fire-weather concerns appear low for much of the CONUS. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. Dry and windy conditions in southern California will be on the increase very late Sunday into Monday morning. Given the current state of fuels and potential for rainfall today and tonight, fire weather concerns should remain low on Sunday. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CST Sat Nov 18 2023/ ...Synopsis... A progressive mid-level flow pattern is expected to persist D2/Sunday as an upper trough over the East Coast continues to move offshore. A broad western US trough is expected to amplify through the weekend before ejecting eastward into the central US by the end of the forecast period. Transient surface high pressure will persist over the eastern third of the country in the wake of an earlier cold front. Cooler and drier conditions are possible over parts of the central and southern Appalachians. Occasional gusty winds near the higher terrain may support brief elevated fire-weather conditions within areas of dry fuels across NC and VA. Localized dry and breezy conditions are also possible over parts of eastern NM. However, with only transient overlap of dry and breezy conditions, widespread fire-weather concerns appear low for much of the CONUS. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0101 PM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... No changes to the ongoing forecast. Dry and windy conditions in southern California will be on the increase very late Sunday into Monday morning. Given the current state of fuels and potential for rainfall today and tonight, fire weather concerns should remain low on Sunday. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0159 AM CST Sat Nov 18 2023/ ...Synopsis... A progressive mid-level flow pattern is expected to persist D2/Sunday as an upper trough over the East Coast continues to move offshore. A broad western US trough is expected to amplify through the weekend before ejecting eastward into the central US by the end of the forecast period. Transient surface high pressure will persist over the eastern third of the country in the wake of an earlier cold front. Cooler and drier conditions are possible over parts of the central and southern Appalachians. Occasional gusty winds near the higher terrain may support brief elevated fire-weather conditions within areas of dry fuels across NC and VA. Localized dry and breezy conditions are also possible over parts of eastern NM. However, with only transient overlap of dry and breezy conditions, widespread fire-weather concerns appear low for much of the CONUS. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1122 AM CST Sat Nov 18 2023 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS SUNDAY NIGHT ACROSS PARTS OF CENTRAL INTO NORTHEASTERN OKLAHOMA... ...SUMMARY... A couple of strong thunderstorms may develop across parts of central into northeastern Oklahoma Sunday evening, accompanied by a risk for small to marginally severe hail. ...Synopsis... Amplification within the westerlies across the mid-latitude eastern Pacific into western North America appears gradually underway. Through Sunday/Sunday night, this is forecast to include building mid-level ridging across the U.S. and Canadian Pacific coast. Downstream, though there remains considerable spread concerning smaller-scale short wave developments, models indicate that large-scale troughing will continue to evolve across the eastern Great Basin and southern Rockies through Mississippi Valley vicinity, with a broad embedded mid-level low evolving across the central Great Plains by 12Z Monday. It appears that this regime will be accompanied by at least modest surface cyclogenesis, generally from southeastern Colorado into the Red River Valley vicinity. In the wake of ongoing low-level cooling/drying across much of the Gulf of Mexico (associated with mid-level troughing now digging off the south Atlantic coast), however, low-level moisture return within the evolving warm sector is forecast to remain relatively modest. Coupled with initially weak lower/mid-tropospheric lapse rates to the lee of the southern Rockies, the potential for widespread, substantive destabilization and strong thunderstorm development appears limited through this period. ...Great Plains... It does appear that elevated moisture return may contribute to thermodynamic profiles sufficient for convection capable of producing lightning, in an arcing band across southwestern Nebraska through central Kansas by the beginning of the period. Guidance suggests similar convective development with increasing potential to produce lightning shortly thereafter, across parts of northwestern Texas into the Red River Valley. This activity likely will be supported by a couple of initial short wave perturbations progressing to the east of the southern Rockies, and may tend to shift with better lingering forcing for ascent into southeastern Kansas/eastern Oklahoma and perhaps northeastern Texas through late Sunday afternoon. By Sunday evening (after 20/00Z), models suggest that strengthening differential thermal advection to the east-northeast of the surface cyclone may contribute to sufficient steepening of mid-level lapse rates to support CAPE increasing in excess of 500 J/kg. Although stronger mid/upper forcing for ascent is forecast to remain to the cool side/above the strengthening warm front, the environment might become conducive for a few strong storms posing a risk for marginally severe hail, generally near/north-northeast of Oklahoma City into the Tulsa vicinity. ..Kerr.. 11/18/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1045 AM CST Sat Nov 18 2023 Valid 181700Z - 191200Z No changes to the ongoing forecast. ..Wendt.. 11/18/2023 .PREV DISCUSSION... /ISSUED 0156 AM CST Sat Nov 18 2023/ ...Synopsis... Within an active mid-level flow pattern, an upper trough and enhanced cyclonic flow aloft over the eastern states is forecast to maintain intensity while moving slowly offshore. Shortwave ridging over the Midwest will favor surface high pressure within a post-frontal air mass over parts of the upper OH Valley and central Appalachians. Gusty northerly winds will support some localized fire-weather concerns over parts of VA and NC Saturday. ...Western VA and NC... With surface high pressure increasing over the upper OH Valley, a northerly surface pressure gradient should develop steadily through the first part of the day. Gusty downslope winds are possible through the early afternoon across parts of the central Appalachians in western VA and NC. A much drier air mass in the wake of the earlier cold front should support a few hours of lower RH below 30%. Given the state of fuels and recent fire activity, elevated fire-weather concerns are possible over western NC into parts of central VA with dry and breezy conditions. Fire-weather concerns should quickly abate into the evening as winds slacken, though drier air should remain in place through the weekend. ...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 1030 AM CST Sat Nov 18 2023 Valid 181630Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...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. ..Goss/Bentley.. 11/18/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1030 AM CST Sat Nov 18 2023 Valid 181630Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are unlikely through tonight. ...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. ..Goss/Bentley.. 11/18/2023 Read more