Severe Storms

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Mon Dec 18 2023 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF COASTAL NEW JERSEY AND SOUTHERN NEW ENGLAND... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible today from near the coast of New Jersey into southern New England. ...Coastal New Jersey/Southern New England... A strong upper-level system over the Great Lakes will move toward the central Appalachians today. Ahead of the system, a lead shortwave trough and an associated deepening surface low will move northward across the Northeast. A cold front near the Mid-Atlantic coast will move eastward into the near-coastal waters with a somewhat moist airmass located head of the front extending northward across southern New England. A few thunderstorms will be possible ahead of the front within this weak instability. An impressive 80 to 100 knot low-level jet will move northward across New England today. Storms that develop across southern New England could have an isolated wind-damage threat, as the stronger convection potentially helps to mix winds toward the surface. However, due to very weak instability, any threat is expected to remain marginal this morning and afternoon. ..Broyles/Thompson.. 12/18/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Mon Dec 18 2023 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF COASTAL NEW JERSEY AND SOUTHERN NEW ENGLAND... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible today from near the coast of New Jersey into southern New England. ...Coastal New Jersey/Southern New England... A strong upper-level system over the Great Lakes will move toward the central Appalachians today. Ahead of the system, a lead shortwave trough and an associated deepening surface low will move northward across the Northeast. A cold front near the Mid-Atlantic coast will move eastward into the near-coastal waters with a somewhat moist airmass located head of the front extending northward across southern New England. A few thunderstorms will be possible ahead of the front within this weak instability. An impressive 80 to 100 knot low-level jet will move northward across New England today. Storms that develop across southern New England could have an isolated wind-damage threat, as the stronger convection potentially helps to mix winds toward the surface. However, due to very weak instability, any threat is expected to remain marginal this morning and afternoon. ..Broyles/Thompson.. 12/18/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Mon Dec 18 2023 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF COASTAL NEW JERSEY AND SOUTHERN NEW ENGLAND... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible today from near the coast of New Jersey into southern New England. ...Coastal New Jersey/Southern New England... A strong upper-level system over the Great Lakes will move toward the central Appalachians today. Ahead of the system, a lead shortwave trough and an associated deepening surface low will move northward across the Northeast. A cold front near the Mid-Atlantic coast will move eastward into the near-coastal waters with a somewhat moist airmass located head of the front extending northward across southern New England. A few thunderstorms will be possible ahead of the front within this weak instability. An impressive 80 to 100 knot low-level jet will move northward across New England today. Storms that develop across southern New England could have an isolated wind-damage threat, as the stronger convection potentially helps to mix winds toward the surface. However, due to very weak instability, any threat is expected to remain marginal this morning and afternoon. ..Broyles/Thompson.. 12/18/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Mon Dec 18 2023 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF COASTAL NEW JERSEY AND SOUTHERN NEW ENGLAND... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible today from near the coast of New Jersey into southern New England. ...Coastal New Jersey/Southern New England... A strong upper-level system over the Great Lakes will move toward the central Appalachians today. Ahead of the system, a lead shortwave trough and an associated deepening surface low will move northward across the Northeast. A cold front near the Mid-Atlantic coast will move eastward into the near-coastal waters with a somewhat moist airmass located head of the front extending northward across southern New England. A few thunderstorms will be possible ahead of the front within this weak instability. An impressive 80 to 100 knot low-level jet will move northward across New England today. Storms that develop across southern New England could have an isolated wind-damage threat, as the stronger convection potentially helps to mix winds toward the surface. However, due to very weak instability, any threat is expected to remain marginal this morning and afternoon. ..Broyles/Thompson.. 12/18/2023 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0655 AM CST Mon Dec 18 2023 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ALONG PARTS OF COASTAL NEW JERSEY AND SOUTHERN NEW ENGLAND... ...SUMMARY... Thunderstorms associated with marginally severe wind gusts will be possible today from near the coast of New Jersey into southern New England. ...Coastal New Jersey/Southern New England... A strong upper-level system over the Great Lakes will move toward the central Appalachians today. Ahead of the system, a lead shortwave trough and an associated deepening surface low will move northward across the Northeast. A cold front near the Mid-Atlantic coast will move eastward into the near-coastal waters with a somewhat moist airmass located head of the front extending northward across southern New England. A few thunderstorms will be possible ahead of the front within this weak instability. An impressive 80 to 100 knot low-level jet will move northward across New England today. Storms that develop across southern New England could have an isolated wind-damage threat, as the stronger convection potentially helps to mix winds toward the surface. However, due to very weak instability, any threat is expected to remain marginal this morning and afternoon. ..Broyles/Thompson.. 12/18/2023 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CST Mon Dec 18 2023 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range guidance continues to suggest that a southern-stream shortwave trough will progress through the southern Plains on D4/Thursday and the Lower MS Valley on D5/Friday. Modest low-level moisture advection will precede this shortwave, supporting showers and isolated thunderstorms. However, overall buoyancy will be limited by warm mid-level temperatures, which should keep the severe potential low. Upper low expected to be off the southern California coast early D4/Thursday is forecast progress eastward across the Southwest/northern Mexico in the wave of the lead southern-stream shortwave, likely reaching the southern High Plains by D6/Saturday. Modest low-level moisture will still be in place across the southern Plains, and this wave should be accompanied by stronger large-scale forcing for ascent and colder mid-level temperatures. This should result in greater buoyancy than with the preceding wave, which may lend itself to stronger thunderstorms. However, timing of this wave remains uncertain, with the amount of overlap between the strongest shear and better buoyancy uncertain as well. These factors limit predictability and overall forecast confidence. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CST Mon Dec 18 2023 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range guidance continues to suggest that a southern-stream shortwave trough will progress through the southern Plains on D4/Thursday and the Lower MS Valley on D5/Friday. Modest low-level moisture advection will precede this shortwave, supporting showers and isolated thunderstorms. However, overall buoyancy will be limited by warm mid-level temperatures, which should keep the severe potential low. Upper low expected to be off the southern California coast early D4/Thursday is forecast progress eastward across the Southwest/northern Mexico in the wave of the lead southern-stream shortwave, likely reaching the southern High Plains by D6/Saturday. Modest low-level moisture will still be in place across the southern Plains, and this wave should be accompanied by stronger large-scale forcing for ascent and colder mid-level temperatures. This should result in greater buoyancy than with the preceding wave, which may lend itself to stronger thunderstorms. However, timing of this wave remains uncertain, with the amount of overlap between the strongest shear and better buoyancy uncertain as well. These factors limit predictability and overall forecast confidence. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CST Mon Dec 18 2023 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range guidance continues to suggest that a southern-stream shortwave trough will progress through the southern Plains on D4/Thursday and the Lower MS Valley on D5/Friday. Modest low-level moisture advection will precede this shortwave, supporting showers and isolated thunderstorms. However, overall buoyancy will be limited by warm mid-level temperatures, which should keep the severe potential low. Upper low expected to be off the southern California coast early D4/Thursday is forecast progress eastward across the Southwest/northern Mexico in the wave of the lead southern-stream shortwave, likely reaching the southern High Plains by D6/Saturday. Modest low-level moisture will still be in place across the southern Plains, and this wave should be accompanied by stronger large-scale forcing for ascent and colder mid-level temperatures. This should result in greater buoyancy than with the preceding wave, which may lend itself to stronger thunderstorms. However, timing of this wave remains uncertain, with the amount of overlap between the strongest shear and better buoyancy uncertain as well. These factors limit predictability and overall forecast confidence. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CST Mon Dec 18 2023 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range guidance continues to suggest that a southern-stream shortwave trough will progress through the southern Plains on D4/Thursday and the Lower MS Valley on D5/Friday. Modest low-level moisture advection will precede this shortwave, supporting showers and isolated thunderstorms. However, overall buoyancy will be limited by warm mid-level temperatures, which should keep the severe potential low. Upper low expected to be off the southern California coast early D4/Thursday is forecast progress eastward across the Southwest/northern Mexico in the wave of the lead southern-stream shortwave, likely reaching the southern High Plains by D6/Saturday. Modest low-level moisture will still be in place across the southern Plains, and this wave should be accompanied by stronger large-scale forcing for ascent and colder mid-level temperatures. This should result in greater buoyancy than with the preceding wave, which may lend itself to stronger thunderstorms. However, timing of this wave remains uncertain, with the amount of overlap between the strongest shear and better buoyancy uncertain as well. These factors limit predictability and overall forecast confidence. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0343 AM CST Mon Dec 18 2023 Valid 211200Z - 261200Z ...DISCUSSION... Medium-range guidance continues to suggest that a southern-stream shortwave trough will progress through the southern Plains on D4/Thursday and the Lower MS Valley on D5/Friday. Modest low-level moisture advection will precede this shortwave, supporting showers and isolated thunderstorms. However, overall buoyancy will be limited by warm mid-level temperatures, which should keep the severe potential low. Upper low expected to be off the southern California coast early D4/Thursday is forecast progress eastward across the Southwest/northern Mexico in the wave of the lead southern-stream shortwave, likely reaching the southern High Plains by D6/Saturday. Modest low-level moisture will still be in place across the southern Plains, and this wave should be accompanied by stronger large-scale forcing for ascent and colder mid-level temperatures. This should result in greater buoyancy than with the preceding wave, which may lend itself to stronger thunderstorms. However, timing of this wave remains uncertain, with the amount of overlap between the strongest shear and better buoyancy uncertain as well. These factors limit predictability and overall forecast confidence. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Dec 18 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes are possible along the central and southern California coast on Wednesday. ...Synopsis... High pressure associated with a dry continental air mass will dominant the sensible weather across much of the central and eastern CONUS during the period. Some limited air mass modification is anticipated across the southern Plains as a low-amplitude shortwave trough approaches from the west. Some precipitation is possible in vicinity of this shortwave, but thermodynamic conditions are not expected to support lightning production. Farther west, an upper low is forecast to begin the period centered about 275 miles west-southwest of SFO, before then progressing southward/south-southwestward throughout the period. Persistent southwesterly flow aloft will help keep profiles moist over much of the central and southern CA coast. Mid-level temperatures across this region are expected to cool throughout the day as the upper low move southward. Modest buoyancy associated with these cooling profiles could support isolated lightning flashes within any deeper, more sustained updrafts. ..Mosier.. 12/18/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Dec 18 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes are possible along the central and southern California coast on Wednesday. ...Synopsis... High pressure associated with a dry continental air mass will dominant the sensible weather across much of the central and eastern CONUS during the period. Some limited air mass modification is anticipated across the southern Plains as a low-amplitude shortwave trough approaches from the west. Some precipitation is possible in vicinity of this shortwave, but thermodynamic conditions are not expected to support lightning production. Farther west, an upper low is forecast to begin the period centered about 275 miles west-southwest of SFO, before then progressing southward/south-southwestward throughout the period. Persistent southwesterly flow aloft will help keep profiles moist over much of the central and southern CA coast. Mid-level temperatures across this region are expected to cool throughout the day as the upper low move southward. Modest buoyancy associated with these cooling profiles could support isolated lightning flashes within any deeper, more sustained updrafts. ..Mosier.. 12/18/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Dec 18 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes are possible along the central and southern California coast on Wednesday. ...Synopsis... High pressure associated with a dry continental air mass will dominant the sensible weather across much of the central and eastern CONUS during the period. Some limited air mass modification is anticipated across the southern Plains as a low-amplitude shortwave trough approaches from the west. Some precipitation is possible in vicinity of this shortwave, but thermodynamic conditions are not expected to support lightning production. Farther west, an upper low is forecast to begin the period centered about 275 miles west-southwest of SFO, before then progressing southward/south-southwestward throughout the period. Persistent southwesterly flow aloft will help keep profiles moist over much of the central and southern CA coast. Mid-level temperatures across this region are expected to cool throughout the day as the upper low move southward. Modest buoyancy associated with these cooling profiles could support isolated lightning flashes within any deeper, more sustained updrafts. ..Mosier.. 12/18/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Dec 18 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes are possible along the central and southern California coast on Wednesday. ...Synopsis... High pressure associated with a dry continental air mass will dominant the sensible weather across much of the central and eastern CONUS during the period. Some limited air mass modification is anticipated across the southern Plains as a low-amplitude shortwave trough approaches from the west. Some precipitation is possible in vicinity of this shortwave, but thermodynamic conditions are not expected to support lightning production. Farther west, an upper low is forecast to begin the period centered about 275 miles west-southwest of SFO, before then progressing southward/south-southwestward throughout the period. Persistent southwesterly flow aloft will help keep profiles moist over much of the central and southern CA coast. Mid-level temperatures across this region are expected to cool throughout the day as the upper low move southward. Modest buoyancy associated with these cooling profiles could support isolated lightning flashes within any deeper, more sustained updrafts. ..Mosier.. 12/18/2023 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0200 AM CST Mon Dec 18 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated lightning flashes are possible along the central and southern California coast on Wednesday. ...Synopsis... High pressure associated with a dry continental air mass will dominant the sensible weather across much of the central and eastern CONUS during the period. Some limited air mass modification is anticipated across the southern Plains as a low-amplitude shortwave trough approaches from the west. Some precipitation is possible in vicinity of this shortwave, but thermodynamic conditions are not expected to support lightning production. Farther west, an upper low is forecast to begin the period centered about 275 miles west-southwest of SFO, before then progressing southward/south-southwestward throughout the period. Persistent southwesterly flow aloft will help keep profiles moist over much of the central and southern CA coast. Mid-level temperatures across this region are expected to cool throughout the day as the upper low move southward. Modest buoyancy associated with these cooling profiles could support isolated lightning flashes within any deeper, more sustained updrafts. ..Mosier.. 12/18/2023 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0147 AM CST Mon Dec 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will meander along the West Coast as upper ridging persists from the Interior West toward the Appalachians tomorrow/Tuesday. While surface lee troughing is expected across the High Plains, surface high pressure and associated cooler air should dominate over the rest of the CONUS. Similar to Day 1, quiescent fire weather conditions are expected over the U.S. ..Squitieri.. 12/18/2023 ...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 0147 AM CST Mon Dec 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will meander along the West Coast as upper ridging persists from the Interior West toward the Appalachians tomorrow/Tuesday. While surface lee troughing is expected across the High Plains, surface high pressure and associated cooler air should dominate over the rest of the CONUS. Similar to Day 1, quiescent fire weather conditions are expected over the U.S. ..Squitieri.. 12/18/2023 ...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 0147 AM CST Mon Dec 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will meander along the West Coast as upper ridging persists from the Interior West toward the Appalachians tomorrow/Tuesday. While surface lee troughing is expected across the High Plains, surface high pressure and associated cooler air should dominate over the rest of the CONUS. Similar to Day 1, quiescent fire weather conditions are expected over the U.S. ..Squitieri.. 12/18/2023 ...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 0147 AM CST Mon Dec 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will meander along the West Coast as upper ridging persists from the Interior West toward the Appalachians tomorrow/Tuesday. While surface lee troughing is expected across the High Plains, surface high pressure and associated cooler air should dominate over the rest of the CONUS. Similar to Day 1, quiescent fire weather conditions are expected over the U.S. ..Squitieri.. 12/18/2023 ...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 0147 AM CST Mon Dec 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... A mid-level trough will meander along the West Coast as upper ridging persists from the Interior West toward the Appalachians tomorrow/Tuesday. While surface lee troughing is expected across the High Plains, surface high pressure and associated cooler air should dominate over the rest of the CONUS. Similar to Day 1, quiescent fire weather conditions are expected over the U.S. ..Squitieri.. 12/18/2023 ...Please see www.spc.noaa.gov/fire for graphic product... Read more