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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1034 AM CST Thu Nov 16 2023 Valid 161700Z - 171200Z ...NO CRITICAL AREAS... The current D1 Fire Weather Outlook is on track with no updates needed. See previous discussion below. ..Thornton.. 11/16/2023 .PREV DISCUSSION... /ISSUED 1239 AM CST Thu Nov 16 2023/ ...Synopsis... Fire weather potential will be limited today across the country. Early-morning water-vapor imagery depicts an upper shortwave trough traversing the U.S./Canadian border. Ahead of this feature, steady surface pressure falls have been observed over the past 12 hours across eastern MT and the Dakotas with a surface low beginning to organize over the region. This low will continue to deepen and drift east through the day as an attendant cold front (already noted over northeast MT/northwest ND) sweeps to the south/southeast. Breezy conditions are expected ahead of and behind the front with winds gusting as high as 25-35 mph. However, the combination of moisture advection ahead of the front and an influx of cooler temperatures behind the front should modulate afternoon RH reductions. Localized elevated conditions are possible in the immediate lee of the central to southern Rockies (mainly from southeast CO to northeast NM), where pre-frontal westerly downslope flow may support areas of 15-20 mph winds and RH values in the 20-30% range. Such conditions are expected to be too transient and localized to warrant highlights. ...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 1028 AM CST Thu Nov 16 2023 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, and a brief tornado or damaging gust cannot be completely ruled out. ...Synopsis... A mid-level trough will traverse the Upper MS Valley as a second mid-level trough meanders off of the CA coastline today. While surface troughing across the MS/OH Valleys will encourage modest moisture return, the surface airmass over most of the CONUS should remain too cool or stable to support organized thunderstorm potential. A renegade thunderstorm or two may occur across portions of central CA and southern AZ in advance of the approaching trough (and associated embedded mid-level impulses ejecting ahead of this feature). However, very scant buoyancy and deep-layer ascent should limit storm coverage to below 10 percent, hence the removal of thunder lines in these areas. The main threat for organized thunderstorms remains over the central and eastern FL Peninsula as a surface low intensifies offshore over the Atlantic shoreline. ...Southeastern Florida Peninsula... A surface low is poised to intensify just offshore of the southeastern FL Peninsula today, with 35+ kts of easterly 850 mb flow expected to overspread some of the counties around and east of Lake Okeechobee during the afternoon and evening hours. This strengthening flow aloft will result in elongated hodographs with some low-level curvature. Instability should be marginal though, with 5.5-6.0 C/km mid-level lapse rates overspreading 68-70F surface dewpoints, contributing to 800-1200 J/kg of tall and thin SBCAPE. Latest guidance consensus depicts semi-discrete storms developing along the northwestern periphery of the surface low across southeast portions of the FL Peninsula this afternoon and evening. Given the aforementioned CAPE/shear parameter space, it is not entirely out of the question for one of the stronger storms to produce a damaging gust or even a brief tornado, hence the introduction of Category 1/Marginal Risk probabilities this outlook. ..Squitieri.. 11/16/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Thu Nov 16 2023 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, and a brief tornado or damaging gust cannot be completely ruled out. ...Synopsis... A mid-level trough will traverse the Upper MS Valley as a second mid-level trough meanders off of the CA coastline today. While surface troughing across the MS/OH Valleys will encourage modest moisture return, the surface airmass over most of the CONUS should remain too cool or stable to support organized thunderstorm potential. A renegade thunderstorm or two may occur across portions of central CA and southern AZ in advance of the approaching trough (and associated embedded mid-level impulses ejecting ahead of this feature). However, very scant buoyancy and deep-layer ascent should limit storm coverage to below 10 percent, hence the removal of thunder lines in these areas. The main threat for organized thunderstorms remains over the central and eastern FL Peninsula as a surface low intensifies offshore over the Atlantic shoreline. ...Southeastern Florida Peninsula... A surface low is poised to intensify just offshore of the southeastern FL Peninsula today, with 35+ kts of easterly 850 mb flow expected to overspread some of the counties around and east of Lake Okeechobee during the afternoon and evening hours. This strengthening flow aloft will result in elongated hodographs with some low-level curvature. Instability should be marginal though, with 5.5-6.0 C/km mid-level lapse rates overspreading 68-70F surface dewpoints, contributing to 800-1200 J/kg of tall and thin SBCAPE. Latest guidance consensus depicts semi-discrete storms developing along the northwestern periphery of the surface low across southeast portions of the FL Peninsula this afternoon and evening. Given the aforementioned CAPE/shear parameter space, it is not entirely out of the question for one of the stronger storms to produce a damaging gust or even a brief tornado, hence the introduction of Category 1/Marginal Risk probabilities this outlook. ..Squitieri.. 11/16/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Thu Nov 16 2023 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, and a brief tornado or damaging gust cannot be completely ruled out. ...Synopsis... A mid-level trough will traverse the Upper MS Valley as a second mid-level trough meanders off of the CA coastline today. While surface troughing across the MS/OH Valleys will encourage modest moisture return, the surface airmass over most of the CONUS should remain too cool or stable to support organized thunderstorm potential. A renegade thunderstorm or two may occur across portions of central CA and southern AZ in advance of the approaching trough (and associated embedded mid-level impulses ejecting ahead of this feature). However, very scant buoyancy and deep-layer ascent should limit storm coverage to below 10 percent, hence the removal of thunder lines in these areas. The main threat for organized thunderstorms remains over the central and eastern FL Peninsula as a surface low intensifies offshore over the Atlantic shoreline. ...Southeastern Florida Peninsula... A surface low is poised to intensify just offshore of the southeastern FL Peninsula today, with 35+ kts of easterly 850 mb flow expected to overspread some of the counties around and east of Lake Okeechobee during the afternoon and evening hours. This strengthening flow aloft will result in elongated hodographs with some low-level curvature. Instability should be marginal though, with 5.5-6.0 C/km mid-level lapse rates overspreading 68-70F surface dewpoints, contributing to 800-1200 J/kg of tall and thin SBCAPE. Latest guidance consensus depicts semi-discrete storms developing along the northwestern periphery of the surface low across southeast portions of the FL Peninsula this afternoon and evening. Given the aforementioned CAPE/shear parameter space, it is not entirely out of the question for one of the stronger storms to produce a damaging gust or even a brief tornado, hence the introduction of Category 1/Marginal Risk probabilities this outlook. ..Squitieri.. 11/16/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Thu Nov 16 2023 Valid 161630Z - 171200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FOR SOUTHEAST PARTS OF THE FLORIDA PENINSULA... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, and a brief tornado or damaging gust cannot be completely ruled out. ...Synopsis... A mid-level trough will traverse the Upper MS Valley as a second mid-level trough meanders off of the CA coastline today. While surface troughing across the MS/OH Valleys will encourage modest moisture return, the surface airmass over most of the CONUS should remain too cool or stable to support organized thunderstorm potential. A renegade thunderstorm or two may occur across portions of central CA and southern AZ in advance of the approaching trough (and associated embedded mid-level impulses ejecting ahead of this feature). However, very scant buoyancy and deep-layer ascent should limit storm coverage to below 10 percent, hence the removal of thunder lines in these areas. The main threat for organized thunderstorms remains over the central and eastern FL Peninsula as a surface low intensifies offshore over the Atlantic shoreline. ...Southeastern Florida Peninsula... A surface low is poised to intensify just offshore of the southeastern FL Peninsula today, with 35+ kts of easterly 850 mb flow expected to overspread some of the counties around and east of Lake Okeechobee during the afternoon and evening hours. This strengthening flow aloft will result in elongated hodographs with some low-level curvature. Instability should be marginal though, with 5.5-6.0 C/km mid-level lapse rates overspreading 68-70F surface dewpoints, contributing to 800-1200 J/kg of tall and thin SBCAPE. Latest guidance consensus depicts semi-discrete storms developing along the northwestern periphery of the surface low across southeast portions of the FL Peninsula this afternoon and evening. Given the aforementioned CAPE/shear parameter space, it is not entirely out of the question for one of the stronger storms to produce a damaging gust or even a brief tornado, hence the introduction of Category 1/Marginal Risk probabilities this outlook. ..Squitieri.. 11/16/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0628 AM CST Thu Nov 16 2023 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, but the bulk of the activity is expected to remain offshore. ...Synopsis... The mid/upper-level pattern over the western CONUS will continue to be characterized by converging split flow in the Rockies region -- downstream from a cut-off synoptic cyclone over the Pacific. That cyclone will begin to move slowly eastward through the period, but will remain well offshore until day 2. An ejecting, deamplifying, basal shortwave trough will cross the central CA coastal areas around 00Z. Forecast soundings suggest deep-enough buoyancy for isolated coastal and inland thunder potential with convection occupying a related swath of large-scale DCVA/lift and strongly difluent mid/upper flow. Isolated elevated thunderstorms also may develop in a low-level warm/moist-advection swath farther southeast from the lower Colorado River Valley across parts of AZ, but with more marginal instability and somewhat weaker lift. A northern-stream trough initially was located from northwestern Hudson Bay southwestward over MT. This feature should amplify and move eastward to northwestern ON, Lake Superior, the upper Mississippi Valley, and the lower Missouri Valley by 12Z tomorrow. Downstream height falls will spread over much of the eastern CONUS. The southeastern periphery of those height falls will encourage a continued slow eastward shift of a weaker, southern-stream, mid/upper-level trough now apparent in moisture-channel imagery over the eastern Gulf. That trough should extend from just off the JAX/DAB area southwestward across the peninsula near FMY by 12Z. As that occurs, a low-level cyclone -- its center now apparent in satellite imagery near 26N89W -- will be left behind to continue drifting southwestward and weakening gradually. A quasistationary frontal zone extends from there roughly eastward across parts of the Keys and Straits to another low -- apparent as part of a prominent MCV on radar and satellite imagery near Bimini. Extensive convection has accompanied the eastern circulation -- which may pivot northward near the Gulf Stream today, but remaining largely offshore. Behind/southwest of it, several stable layers aloft -- sampled by 12Z KEY/MFL soundings, should inhibit convective potential over south FL. Scattered showers and isolated thunderstorms may occur in MCV-enhanced/deep low-level easterlies farther north across central/eastern FL. Adequate speed shear, but little directional change in the easterly layer, will render modest, somewhat hook-shaped low-level hodographs, beneath weak midlevel southerlies/southwesterlies. A few cells may exhibit weak rotation inland, or produce strong gusts with downdrafts superimposed on the ambient/gradient flow, but the greatest convective coverage and intensity should be out to sea. ..Edwards/Gleason.. 11/16/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0628 AM CST Thu Nov 16 2023 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, but the bulk of the activity is expected to remain offshore. ...Synopsis... The mid/upper-level pattern over the western CONUS will continue to be characterized by converging split flow in the Rockies region -- downstream from a cut-off synoptic cyclone over the Pacific. That cyclone will begin to move slowly eastward through the period, but will remain well offshore until day 2. An ejecting, deamplifying, basal shortwave trough will cross the central CA coastal areas around 00Z. Forecast soundings suggest deep-enough buoyancy for isolated coastal and inland thunder potential with convection occupying a related swath of large-scale DCVA/lift and strongly difluent mid/upper flow. Isolated elevated thunderstorms also may develop in a low-level warm/moist-advection swath farther southeast from the lower Colorado River Valley across parts of AZ, but with more marginal instability and somewhat weaker lift. A northern-stream trough initially was located from northwestern Hudson Bay southwestward over MT. This feature should amplify and move eastward to northwestern ON, Lake Superior, the upper Mississippi Valley, and the lower Missouri Valley by 12Z tomorrow. Downstream height falls will spread over much of the eastern CONUS. The southeastern periphery of those height falls will encourage a continued slow eastward shift of a weaker, southern-stream, mid/upper-level trough now apparent in moisture-channel imagery over the eastern Gulf. That trough should extend from just off the JAX/DAB area southwestward across the peninsula near FMY by 12Z. As that occurs, a low-level cyclone -- its center now apparent in satellite imagery near 26N89W -- will be left behind to continue drifting southwestward and weakening gradually. A quasistationary frontal zone extends from there roughly eastward across parts of the Keys and Straits to another low -- apparent as part of a prominent MCV on radar and satellite imagery near Bimini. Extensive convection has accompanied the eastern circulation -- which may pivot northward near the Gulf Stream today, but remaining largely offshore. Behind/southwest of it, several stable layers aloft -- sampled by 12Z KEY/MFL soundings, should inhibit convective potential over south FL. Scattered showers and isolated thunderstorms may occur in MCV-enhanced/deep low-level easterlies farther north across central/eastern FL. Adequate speed shear, but little directional change in the easterly layer, will render modest, somewhat hook-shaped low-level hodographs, beneath weak midlevel southerlies/southwesterlies. A few cells may exhibit weak rotation inland, or produce strong gusts with downdrafts superimposed on the ambient/gradient flow, but the greatest convective coverage and intensity should be out to sea. ..Edwards/Gleason.. 11/16/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0628 AM CST Thu Nov 16 2023 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, but the bulk of the activity is expected to remain offshore. ...Synopsis... The mid/upper-level pattern over the western CONUS will continue to be characterized by converging split flow in the Rockies region -- downstream from a cut-off synoptic cyclone over the Pacific. That cyclone will begin to move slowly eastward through the period, but will remain well offshore until day 2. An ejecting, deamplifying, basal shortwave trough will cross the central CA coastal areas around 00Z. Forecast soundings suggest deep-enough buoyancy for isolated coastal and inland thunder potential with convection occupying a related swath of large-scale DCVA/lift and strongly difluent mid/upper flow. Isolated elevated thunderstorms also may develop in a low-level warm/moist-advection swath farther southeast from the lower Colorado River Valley across parts of AZ, but with more marginal instability and somewhat weaker lift. A northern-stream trough initially was located from northwestern Hudson Bay southwestward over MT. This feature should amplify and move eastward to northwestern ON, Lake Superior, the upper Mississippi Valley, and the lower Missouri Valley by 12Z tomorrow. Downstream height falls will spread over much of the eastern CONUS. The southeastern periphery of those height falls will encourage a continued slow eastward shift of a weaker, southern-stream, mid/upper-level trough now apparent in moisture-channel imagery over the eastern Gulf. That trough should extend from just off the JAX/DAB area southwestward across the peninsula near FMY by 12Z. As that occurs, a low-level cyclone -- its center now apparent in satellite imagery near 26N89W -- will be left behind to continue drifting southwestward and weakening gradually. A quasistationary frontal zone extends from there roughly eastward across parts of the Keys and Straits to another low -- apparent as part of a prominent MCV on radar and satellite imagery near Bimini. Extensive convection has accompanied the eastern circulation -- which may pivot northward near the Gulf Stream today, but remaining largely offshore. Behind/southwest of it, several stable layers aloft -- sampled by 12Z KEY/MFL soundings, should inhibit convective potential over south FL. Scattered showers and isolated thunderstorms may occur in MCV-enhanced/deep low-level easterlies farther north across central/eastern FL. Adequate speed shear, but little directional change in the easterly layer, will render modest, somewhat hook-shaped low-level hodographs, beneath weak midlevel southerlies/southwesterlies. A few cells may exhibit weak rotation inland, or produce strong gusts with downdrafts superimposed on the ambient/gradient flow, but the greatest convective coverage and intensity should be out to sea. ..Edwards/Gleason.. 11/16/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0628 AM CST Thu Nov 16 2023 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, but the bulk of the activity is expected to remain offshore. ...Synopsis... The mid/upper-level pattern over the western CONUS will continue to be characterized by converging split flow in the Rockies region -- downstream from a cut-off synoptic cyclone over the Pacific. That cyclone will begin to move slowly eastward through the period, but will remain well offshore until day 2. An ejecting, deamplifying, basal shortwave trough will cross the central CA coastal areas around 00Z. Forecast soundings suggest deep-enough buoyancy for isolated coastal and inland thunder potential with convection occupying a related swath of large-scale DCVA/lift and strongly difluent mid/upper flow. Isolated elevated thunderstorms also may develop in a low-level warm/moist-advection swath farther southeast from the lower Colorado River Valley across parts of AZ, but with more marginal instability and somewhat weaker lift. A northern-stream trough initially was located from northwestern Hudson Bay southwestward over MT. This feature should amplify and move eastward to northwestern ON, Lake Superior, the upper Mississippi Valley, and the lower Missouri Valley by 12Z tomorrow. Downstream height falls will spread over much of the eastern CONUS. The southeastern periphery of those height falls will encourage a continued slow eastward shift of a weaker, southern-stream, mid/upper-level trough now apparent in moisture-channel imagery over the eastern Gulf. That trough should extend from just off the JAX/DAB area southwestward across the peninsula near FMY by 12Z. As that occurs, a low-level cyclone -- its center now apparent in satellite imagery near 26N89W -- will be left behind to continue drifting southwestward and weakening gradually. A quasistationary frontal zone extends from there roughly eastward across parts of the Keys and Straits to another low -- apparent as part of a prominent MCV on radar and satellite imagery near Bimini. Extensive convection has accompanied the eastern circulation -- which may pivot northward near the Gulf Stream today, but remaining largely offshore. Behind/southwest of it, several stable layers aloft -- sampled by 12Z KEY/MFL soundings, should inhibit convective potential over south FL. Scattered showers and isolated thunderstorms may occur in MCV-enhanced/deep low-level easterlies farther north across central/eastern FL. Adequate speed shear, but little directional change in the easterly layer, will render modest, somewhat hook-shaped low-level hodographs, beneath weak midlevel southerlies/southwesterlies. A few cells may exhibit weak rotation inland, or produce strong gusts with downdrafts superimposed on the ambient/gradient flow, but the greatest convective coverage and intensity should be out to sea. ..Edwards/Gleason.. 11/16/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0628 AM CST Thu Nov 16 2023 Valid 161300Z - 171200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few strong storms may threaten the southern and eastern Florida Peninsula, but the bulk of the activity is expected to remain offshore. ...Synopsis... The mid/upper-level pattern over the western CONUS will continue to be characterized by converging split flow in the Rockies region -- downstream from a cut-off synoptic cyclone over the Pacific. That cyclone will begin to move slowly eastward through the period, but will remain well offshore until day 2. An ejecting, deamplifying, basal shortwave trough will cross the central CA coastal areas around 00Z. Forecast soundings suggest deep-enough buoyancy for isolated coastal and inland thunder potential with convection occupying a related swath of large-scale DCVA/lift and strongly difluent mid/upper flow. Isolated elevated thunderstorms also may develop in a low-level warm/moist-advection swath farther southeast from the lower Colorado River Valley across parts of AZ, but with more marginal instability and somewhat weaker lift. A northern-stream trough initially was located from northwestern Hudson Bay southwestward over MT. This feature should amplify and move eastward to northwestern ON, Lake Superior, the upper Mississippi Valley, and the lower Missouri Valley by 12Z tomorrow. Downstream height falls will spread over much of the eastern CONUS. The southeastern periphery of those height falls will encourage a continued slow eastward shift of a weaker, southern-stream, mid/upper-level trough now apparent in moisture-channel imagery over the eastern Gulf. That trough should extend from just off the JAX/DAB area southwestward across the peninsula near FMY by 12Z. As that occurs, a low-level cyclone -- its center now apparent in satellite imagery near 26N89W -- will be left behind to continue drifting southwestward and weakening gradually. A quasistationary frontal zone extends from there roughly eastward across parts of the Keys and Straits to another low -- apparent as part of a prominent MCV on radar and satellite imagery near Bimini. Extensive convection has accompanied the eastern circulation -- which may pivot northward near the Gulf Stream today, but remaining largely offshore. Behind/southwest of it, several stable layers aloft -- sampled by 12Z KEY/MFL soundings, should inhibit convective potential over south FL. Scattered showers and isolated thunderstorms may occur in MCV-enhanced/deep low-level easterlies farther north across central/eastern FL. Adequate speed shear, but little directional change in the easterly layer, will render modest, somewhat hook-shaped low-level hodographs, beneath weak midlevel southerlies/southwesterlies. A few cells may exhibit weak rotation inland, or produce strong gusts with downdrafts superimposed on the ambient/gradient flow, but the greatest convective coverage and intensity should be out to sea. ..Edwards/Gleason.. 11/16/2023 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0400 AM CST Thu Nov 16 2023 Valid 191200Z - 241200Z ...DISCUSSION... ...Sunday/Day 4 and Monday/Day 5... A well-defined 80 to 100 kt mid-level jet will translate quickly southeastward across the Desert Southwest on Sunday. As a result, a rapid deepening of an upper-level trough is expected over the Rockies. The exit region of the jet is forecast to overspread the southern Plains on Sunday, with moisture return taking place across the southern Plains. Surface dewpoints should reach the 60s F across parts of central and east Texas by afternoon. As large-scale ascent increases across the southern Plains, thunderstorm development is expected late Sunday afternoon along and near the moist axis from northeast Texas into east-central Oklahoma. The models are in reasonably good agreement on this. A narrow 15 percent contour has been added along the zone with the greatest severe-weather potential. Sunday night into Monday, an upper-level low is forecast to develop over the central Plains, as the southern extension of the associated trough moves quickly from the Desert Southwest into the southern Plains. New medium-range model forecasts are more aggressive with moisture return across the western and central Gulf Coast region. By mid afternoon on Monday, surface dewpoints are forecast to reach the 60s F from the Texas Coastal Plain east-northeastward throughout the lower Mississippi Valley and much of the central Gulf Coast states, with a broad low-level jet developing across the moist sector. In association with the low-level jet, scattered thunderstorms are expected to develop during the day and move east-northeastward across the central Gulf Coast states. Although instability across the moist sector is forecast to remain weak, strong forcing and moderate to strong deep-layer shear will likely be favorable for severe storms. At this time, the lack of instability suggests there is uncertainty concerning how large the severe-threat area will be. Have added a 15 percent contour in the area where confidence is the greatest. ...Tuesday/Day 6 to Thursday/Day 8... From Tuesday to Thursday, the mid-level trough is forecast to move from the Mississippi Valley to the Eastern Seaboard. Thunderstorms will be possible on Tuesday along parts of the Eastern Seaboard ahead of a fast-moving cold front. Surface high pressure is expected to move into much of the central and eastern U.S. on Wednesday and Thursday. The associated dry airmass would limit thunderstorm potential in most areas across the continental U.S. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Thu Nov 16 2023 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated to scattered thunderstorms will be possible on Saturday and Saturday night along parts of the West Coast, across parts of the Four Corners and Desert Southwest, in parts of the southern and central High Plains, and in southeast Florida. ...DISCUSSION... At mid-levels, a trough is forecast to move into central California on Saturday, with another trough moving into the Pacific Northwest Saturday night. As these two troughs move inland, isolated thunderstorms will be possible. Another shortwave trough is forecast to move from the Four Corners Saturday afternoon to the southern Rockies Saturday night. Along and ahead the trough, thunderstorms will be possible during the afternoon and early evening from near the Mogollon Rim eastward into central and northern New Mexico. Thunderstorms may also develop Saturday night near the axis of a low-level jet from west Texas to western Kansas. Isolated thunderstorms could also develop in southeast Florida. No severe threat is expected across the continental U.S. Saturday and Saturday night. ..Broyles.. 11/16/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Thu Nov 16 2023 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated to scattered thunderstorms will be possible on Saturday and Saturday night along parts of the West Coast, across parts of the Four Corners and Desert Southwest, in parts of the southern and central High Plains, and in southeast Florida. ...DISCUSSION... At mid-levels, a trough is forecast to move into central California on Saturday, with another trough moving into the Pacific Northwest Saturday night. As these two troughs move inland, isolated thunderstorms will be possible. Another shortwave trough is forecast to move from the Four Corners Saturday afternoon to the southern Rockies Saturday night. Along and ahead the trough, thunderstorms will be possible during the afternoon and early evening from near the Mogollon Rim eastward into central and northern New Mexico. Thunderstorms may also develop Saturday night near the axis of a low-level jet from west Texas to western Kansas. Isolated thunderstorms could also develop in southeast Florida. No severe threat is expected across the continental U.S. Saturday and Saturday night. ..Broyles.. 11/16/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Thu Nov 16 2023 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated to scattered thunderstorms will be possible on Saturday and Saturday night along parts of the West Coast, across parts of the Four Corners and Desert Southwest, in parts of the southern and central High Plains, and in southeast Florida. ...DISCUSSION... At mid-levels, a trough is forecast to move into central California on Saturday, with another trough moving into the Pacific Northwest Saturday night. As these two troughs move inland, isolated thunderstorms will be possible. Another shortwave trough is forecast to move from the Four Corners Saturday afternoon to the southern Rockies Saturday night. Along and ahead the trough, thunderstorms will be possible during the afternoon and early evening from near the Mogollon Rim eastward into central and northern New Mexico. Thunderstorms may also develop Saturday night near the axis of a low-level jet from west Texas to western Kansas. Isolated thunderstorms could also develop in southeast Florida. No severe threat is expected across the continental U.S. Saturday and Saturday night. ..Broyles.. 11/16/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0227 AM CST Thu Nov 16 2023 Valid 181200Z - 191200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated to scattered thunderstorms will be possible on Saturday and Saturday night along parts of the West Coast, across parts of the Four Corners and Desert Southwest, in parts of the southern and central High Plains, and in southeast Florida. ...DISCUSSION... At mid-levels, a trough is forecast to move into central California on Saturday, with another trough moving into the Pacific Northwest Saturday night. As these two troughs move inland, isolated thunderstorms will be possible. Another shortwave trough is forecast to move from the Four Corners Saturday afternoon to the southern Rockies Saturday night. Along and ahead the trough, thunderstorms will be possible during the afternoon and early evening from near the Mogollon Rim eastward into central and northern New Mexico. Thunderstorms may also develop Saturday night near the axis of a low-level jet from west Texas to western Kansas. Isolated thunderstorms could also develop in southeast Florida. No severe threat is expected across the continental U.S. Saturday and Saturday night. ..Broyles.. 11/16/2023 Read more