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SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1005 AM CST Tue Feb 20 2024 Valid 201630Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ..Western States... A large upper low remains off the Pacific Northwest coast with a series of smaller shortwave troughs rotating inland through the forecast period. This will lead to occasional clusters of showers and isolated thunderstorms over parts of CA, and inland into portions of OR/ID and NV/UT/AZ. Overall coverage of thunderstorms should remain quite sparse. ..Hart.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0632 AM CST Tue Feb 20 2024 Valid 201300Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...Synopsis/Discussion... A progressive trough-ridge-trough pattern will characterize mid/upper levels through the period. The eastern synoptic trough will move offshore to the Atlantic overnight, after consolidating from shortwave troughs now over the Mid-South/Tennessee Valley region, eastern NC and the FL Peninsula and vicinity. A low- amplitude synoptic ridge, with broadly anticyclonic bracketing flow, will cross the central CONUS. A well-developed synoptic trough was evident in moisture-channel imagery off the West Coast, with embedded cyclone center about 150 nm west-southwest of OTH. A basal shortwave trough was readily apparent well west of southern CA and Baja, between 27N-35N, approaching 130W. As the cyclone weakens and shifts north- northeastward toward the AST/HQM area by the end of the period, the basal trough should weaken slightly and move eastward to a position just offshore from southern CA and northern Baja. A series of small/low-amplitude shortwaves and vorticity lobes will traverse the southwest flow preceding the northeastern Pacific trough, contributing to cooling aloft and modest low/middle-level moistening over portions of the interior West, as well as atop the marine air mass near the coast. Associated 100-500 J/kg MUCAPE (greatest near the coast) will support episodic thunder potential, mainly over the outlook areas, though very isolated flashes cannot be ruled out over much of the area west of the Rockies. The combined shear/ instability parameter space should be too weak to support severe potential. ..Edwards/Mosier.. 02/20/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0328 AM CST Tue Feb 20 2024 Valid 231200Z - 281200Z ...DISCUSSION... The extended forecast range will be characterized by progressive upper flow featuring an eastern U.S. trough and ridge over the West through Saturday (day 5). Low potential for severe thunderstorms is forecast through at least Monday (day 7), before models indicate the possibility for northward moisture return into the southern Great Plains/Arklatex by Tuesday (day 8). There is large model variability by early next week, which will result in substantial uncertainty/predictability concerns. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Tue Feb 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast for Thursday across the contiguous United States. ...Synopsis... A belt of strong westerly mid-level flow will overspread the Southeast, while an attendant disturbance over MO weakens as it moves into the Upper OH Valley. Concurrently, a large-scale trough will amplify over the eastern half of the CONUS. A surface low over MO will weaken as it develops east into the OH Valley, while a cold front pushes southeast from the Ozark Plateau through much of the lower MS/TN Valleys. Showers and isolated thunderstorms will likely be ongoing within a warm-air advection regime over the Ozarks in association with a LLJ centered over the lower MS Valley. This activity will likely spread east into a more weakly unstable airmass, as moisture return north into the Mid South/OH Valley will remain limited (lowest 100 mb mean mixing ratios 7-8 g/kg). Considerable cloud cover will likely inhibit strong heating and limit destabilization. By late in the day into the overnight, showers and possibly a few thunderstorms may develop along the southeastward-surging front across TN southeastward into AL/GA. ..Smith.. 02/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Tue Feb 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast for Thursday across the contiguous United States. ...Synopsis... A belt of strong westerly mid-level flow will overspread the Southeast, while an attendant disturbance over MO weakens as it moves into the Upper OH Valley. Concurrently, a large-scale trough will amplify over the eastern half of the CONUS. A surface low over MO will weaken as it develops east into the OH Valley, while a cold front pushes southeast from the Ozark Plateau through much of the lower MS/TN Valleys. Showers and isolated thunderstorms will likely be ongoing within a warm-air advection regime over the Ozarks in association with a LLJ centered over the lower MS Valley. This activity will likely spread east into a more weakly unstable airmass, as moisture return north into the Mid South/OH Valley will remain limited (lowest 100 mb mean mixing ratios 7-8 g/kg). Considerable cloud cover will likely inhibit strong heating and limit destabilization. By late in the day into the overnight, showers and possibly a few thunderstorms may develop along the southeastward-surging front across TN southeastward into AL/GA. ..Smith.. 02/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Tue Feb 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast for Thursday across the contiguous United States. ...Synopsis... A belt of strong westerly mid-level flow will overspread the Southeast, while an attendant disturbance over MO weakens as it moves into the Upper OH Valley. Concurrently, a large-scale trough will amplify over the eastern half of the CONUS. A surface low over MO will weaken as it develops east into the OH Valley, while a cold front pushes southeast from the Ozark Plateau through much of the lower MS/TN Valleys. Showers and isolated thunderstorms will likely be ongoing within a warm-air advection regime over the Ozarks in association with a LLJ centered over the lower MS Valley. This activity will likely spread east into a more weakly unstable airmass, as moisture return north into the Mid South/OH Valley will remain limited (lowest 100 mb mean mixing ratios 7-8 g/kg). Considerable cloud cover will likely inhibit strong heating and limit destabilization. By late in the day into the overnight, showers and possibly a few thunderstorms may develop along the southeastward-surging front across TN southeastward into AL/GA. ..Smith.. 02/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Tue Feb 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast for Thursday across the contiguous United States. ...Synopsis... A belt of strong westerly mid-level flow will overspread the Southeast, while an attendant disturbance over MO weakens as it moves into the Upper OH Valley. Concurrently, a large-scale trough will amplify over the eastern half of the CONUS. A surface low over MO will weaken as it develops east into the OH Valley, while a cold front pushes southeast from the Ozark Plateau through much of the lower MS/TN Valleys. Showers and isolated thunderstorms will likely be ongoing within a warm-air advection regime over the Ozarks in association with a LLJ centered over the lower MS Valley. This activity will likely spread east into a more weakly unstable airmass, as moisture return north into the Mid South/OH Valley will remain limited (lowest 100 mb mean mixing ratios 7-8 g/kg). Considerable cloud cover will likely inhibit strong heating and limit destabilization. By late in the day into the overnight, showers and possibly a few thunderstorms may develop along the southeastward-surging front across TN southeastward into AL/GA. ..Smith.. 02/20/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0220 AM CST Tue Feb 20 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Organized severe thunderstorms are not currently forecast for Thursday across the contiguous United States. ...Synopsis... A belt of strong westerly mid-level flow will overspread the Southeast, while an attendant disturbance over MO weakens as it moves into the Upper OH Valley. Concurrently, a large-scale trough will amplify over the eastern half of the CONUS. A surface low over MO will weaken as it develops east into the OH Valley, while a cold front pushes southeast from the Ozark Plateau through much of the lower MS/TN Valleys. Showers and isolated thunderstorms will likely be ongoing within a warm-air advection regime over the Ozarks in association with a LLJ centered over the lower MS Valley. This activity will likely spread east into a more weakly unstable airmass, as moisture return north into the Mid South/OH Valley will remain limited (lowest 100 mb mean mixing ratios 7-8 g/kg). Considerable cloud cover will likely inhibit strong heating and limit destabilization. By late in the day into the overnight, showers and possibly a few thunderstorms may develop along the southeastward-surging front across TN southeastward into AL/GA. ..Smith.. 02/20/2024 Read more