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SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1116 PM CST Fri Jan 17 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY INTO TONIGHT ACROSS THE FLORIDA PANHANDLE VICINITY INTO PORTIONS OF NORTHERN FLORIDA AND THE WEST CENTRAL FLORIDA COASTAL AREAS...ADJACENT PORTIONS OF SOUTHEASTERN ALABAMA AND SOUTHWESTERN GEORGIA... ...SUMMARY... Strong thunderstorms may impact parts of the eastern Gulf Coast vicinity today through tonight, and pose some risk for locally damaging wind gusts and perhaps a tornado or two. ...Synopsis... Amplification of the mid/upper flow continues across the eastern Pacific into North America. Today through tonight, this is likely to include a consolidating, positively tilted large-scale trough encompassing much of North America. Beneath an associated confluent regime across the Rockies into the Appalachians, cold surface ridging is forecast to build southeastward to the lee of the Rockies. An evolving frontal zone on the leading edge of the colder air appears likely to be in the process of advancing off of the northern and middle Atlantic Seaboard, and through the northwestern Gulf of Mexico, by late this evening into the overnight hours. While stronger surface cyclogenesis becomes focused southeast through east of Hudson Bay, a weak wave may develop and migrate along the front across the eastern Gulf Coast through south Atlantic Coast vicinity by late tonight. In the wake of recent prior cold intrusions, the boundary-layer over the Gulf of Mexico is still in the process of recovering. However, models suggest that moistening within the pre-frontal southwesterly to west-southwesterly return flow might become sufficient for weak boundary-layer destabilization inland across the northeastern Gulf coast. ...Eastern Gulf States... A strong belt of initially westerly mid/upper flow (associated with remnant perturbations emerging from the southern mid-latitude and subtropical eastern Pacific) is in the process of overspreading the northern Mexican Plateau and Gulf Coast states. Including speeds of 70-90 kt as low as the 500 mb level, deep-layer shear within the warm sector of the evolving weak surface wave will be strong and supportive of a conditional risk for organized severe thunderstorm development. Given the weak nature of the frontal wave, the lack of stronger forcing for ascent and likelihood of generally modest low-level hodographs still seem likely to limit the overall severe weather potential. However, with weak boundary-layer destabilization forecast across the northeastern Gulf of Mexico into at least the vicinity of coastal areas (from the western Florida Panhandle area by midday into areas near/north of Tampa by 12Z Sunday), the risk for severe thunderstorms may not be completely negligible. Isolated supercell development appears possible within the pre-frontal warm advection regime, initiating within the more buoyant offshore environment, before approaching coastal areas with a risk for producing a tornado or severe wind gust. This activity could spread or develop inland. However, the potential areal extent of any weak boundary-layer destabilization inland of coastal areas, across portions of Alabama/Georgia/northern Florida is more uncertain. Based on a consensus of model output, this seems most probable in a small corridor across the western Florida Panhandle and perhaps adjacent portions of southeastern Alabama/southwestern Georgia and northern Florida this afternoon. Upscale convective growth into tonight may be aided by forcing associated with low-amplitude perturbations/coupled speed maxima within the strong mid/upper flow. By late tonight, this may include the evolution of an extensive pre-frontal line extending offshore of the Carolina coast through northern Florida into the northeastern Gulf, approaching the Tampa vicinity. ..Kerr/Halbert.. 01/18/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1116 PM CST Fri Jan 17 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS TODAY INTO TONIGHT ACROSS THE FLORIDA PANHANDLE VICINITY INTO PORTIONS OF NORTHERN FLORIDA AND THE WEST CENTRAL FLORIDA COASTAL AREAS...ADJACENT PORTIONS OF SOUTHEASTERN ALABAMA AND SOUTHWESTERN GEORGIA... ...SUMMARY... Strong thunderstorms may impact parts of the eastern Gulf Coast vicinity today through tonight, and pose some risk for locally damaging wind gusts and perhaps a tornado or two. ...Synopsis... Amplification of the mid/upper flow continues across the eastern Pacific into North America. Today through tonight, this is likely to include a consolidating, positively tilted large-scale trough encompassing much of North America. Beneath an associated confluent regime across the Rockies into the Appalachians, cold surface ridging is forecast to build southeastward to the lee of the Rockies. An evolving frontal zone on the leading edge of the colder air appears likely to be in the process of advancing off of the northern and middle Atlantic Seaboard, and through the northwestern Gulf of Mexico, by late this evening into the overnight hours. While stronger surface cyclogenesis becomes focused southeast through east of Hudson Bay, a weak wave may develop and migrate along the front across the eastern Gulf Coast through south Atlantic Coast vicinity by late tonight. In the wake of recent prior cold intrusions, the boundary-layer over the Gulf of Mexico is still in the process of recovering. However, models suggest that moistening within the pre-frontal southwesterly to west-southwesterly return flow might become sufficient for weak boundary-layer destabilization inland across the northeastern Gulf coast. ...Eastern Gulf States... A strong belt of initially westerly mid/upper flow (associated with remnant perturbations emerging from the southern mid-latitude and subtropical eastern Pacific) is in the process of overspreading the northern Mexican Plateau and Gulf Coast states. Including speeds of 70-90 kt as low as the 500 mb level, deep-layer shear within the warm sector of the evolving weak surface wave will be strong and supportive of a conditional risk for organized severe thunderstorm development. Given the weak nature of the frontal wave, the lack of stronger forcing for ascent and likelihood of generally modest low-level hodographs still seem likely to limit the overall severe weather potential. However, with weak boundary-layer destabilization forecast across the northeastern Gulf of Mexico into at least the vicinity of coastal areas (from the western Florida Panhandle area by midday into areas near/north of Tampa by 12Z Sunday), the risk for severe thunderstorms may not be completely negligible. Isolated supercell development appears possible within the pre-frontal warm advection regime, initiating within the more buoyant offshore environment, before approaching coastal areas with a risk for producing a tornado or severe wind gust. This activity could spread or develop inland. However, the potential areal extent of any weak boundary-layer destabilization inland of coastal areas, across portions of Alabama/Georgia/northern Florida is more uncertain. Based on a consensus of model output, this seems most probable in a small corridor across the western Florida Panhandle and perhaps adjacent portions of southeastern Alabama/southwestern Georgia and northern Florida this afternoon. Upscale convective growth into tonight may be aided by forcing associated with low-amplitude perturbations/coupled speed maxima within the strong mid/upper flow. By late tonight, this may include the evolution of an extensive pre-frontal line extending offshore of the Carolina coast through northern Florida into the northeastern Gulf, approaching the Tampa vicinity. ..Kerr/Halbert.. 01/18/2025 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1234 AM CST Sat Jan 18 2025 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... Tomorrow (Sunday), cold air will continue to dominate most of the CONUS. While some locally breezy conditions may develop over portions of northern Arizona, meteorological conditions and fuels are not supportive of fire-weather highlights. ..Halbert.. 01/18/2025 ...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 1234 AM CST Sat Jan 18 2025 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... Tomorrow (Sunday), cold air will continue to dominate most of the CONUS. While some locally breezy conditions may develop over portions of northern Arizona, meteorological conditions and fuels are not supportive of fire-weather highlights. ..Halbert.. 01/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1233 AM CST Sat Jan 18 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... A cold airmass, associated with a large-scale mid-level trough, will dominate much of the CONUS on Saturday. On the western periphery of the trough, where the geopotential height gradient is strongest between an embedded shortwave trough and broad ridging off the U.S. West Coast, a strong jet streak is forecast to progress south-southeastward across the Intermountain West. This will result in dry and windy conditions across the Four Corners region, with sustained winds reaching 20-25 MPH. Despite the strong surface winds and low relative humidity, generally cooler temperatures and fuels that aren't overly receptive to wildfire spread will keep any fire threat localized. ..Halbert.. 01/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1233 AM CST Sat Jan 18 2025 Valid 181200Z - 191200Z ...NO CRITICAL AREAS... ...Synopsis... A cold airmass, associated with a large-scale mid-level trough, will dominate much of the CONUS on Saturday. On the western periphery of the trough, where the geopotential height gradient is strongest between an embedded shortwave trough and broad ridging off the U.S. West Coast, a strong jet streak is forecast to progress south-southeastward across the Intermountain West. This will result in dry and windy conditions across the Four Corners region, with sustained winds reaching 20-25 MPH. Despite the strong surface winds and low relative humidity, generally cooler temperatures and fuels that aren't overly receptive to wildfire spread will keep any fire threat localized. ..Halbert.. 01/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0641 PM CST Fri Jan 17 2025 Valid 180100Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered, generally weak, thunderstorm activity is possible tonight across parts of the lower Mississippi into Tennessee Valleys and adjacent Gulf Coast vicinity. ...01Z Update... Downstream of building mid/upper ridging across the northeast Pacific through Alaska/Yukon vicinity, large-scale mid/upper trough amplification is underway along a positively tilted axis roughly extending across the Hudson Bay vicinity into the lee of the southern Rockies. This has been preceded by the east-northeastward acceleration of initially significant troughing emerging from the southern mid-latitude/subtropical eastern Pacific, which is becoming increasingly sheared across the southern tier of the United States. One still notable embedded short wave perturbation is in the process of accelerating east-northeast of the southern Great Plains, and forecast to approach the southern Appalachians by 12Z Saturday. In response to the aforementioned short wave, low-level warm advection now overspreading the southeastern Great Plains and lower Mississippi Valley will continue to develop eastward tonight. Even with a sizable westerly component to the low-level wind fields, it appears that elevated moisture return emanating from a slowly modifying boundary layer over the Gulf of Mexico will contribute to weak destabilization. Latest model output continues to suggest that this may become sufficient for scattered, generally weak, thunderstorm activity as cooling aloft begins to overspread areas across and east/southeast of the lower Mississippi Valley by around 05-06Z. ..Kerr.. 01/18/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0641 PM CST Fri Jan 17 2025 Valid 180100Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Scattered, generally weak, thunderstorm activity is possible tonight across parts of the lower Mississippi into Tennessee Valleys and adjacent Gulf Coast vicinity. ...01Z Update... Downstream of building mid/upper ridging across the northeast Pacific through Alaska/Yukon vicinity, large-scale mid/upper trough amplification is underway along a positively tilted axis roughly extending across the Hudson Bay vicinity into the lee of the southern Rockies. This has been preceded by the east-northeastward acceleration of initially significant troughing emerging from the southern mid-latitude/subtropical eastern Pacific, which is becoming increasingly sheared across the southern tier of the United States. One still notable embedded short wave perturbation is in the process of accelerating east-northeast of the southern Great Plains, and forecast to approach the southern Appalachians by 12Z Saturday. In response to the aforementioned short wave, low-level warm advection now overspreading the southeastern Great Plains and lower Mississippi Valley will continue to develop eastward tonight. Even with a sizable westerly component to the low-level wind fields, it appears that elevated moisture return emanating from a slowly modifying boundary layer over the Gulf of Mexico will contribute to weak destabilization. Latest model output continues to suggest that this may become sufficient for scattered, generally weak, thunderstorm activity as cooling aloft begins to overspread areas across and east/southeast of the lower Mississippi Valley by around 05-06Z. ..Kerr.. 01/18/2025 Read more

No watches are valid as of Fri Jan 17 22:47:02 UTC 2025.

No Mesoscale Discussions are in effect as of Fri Jan 17 22:47:02 UTC 2025.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0359 PM CST Fri Jan 17 2025 Valid 191200Z - 251200Z ...Southern California... Within the base of a highly amplified, positive-tilt large-scale trough over the West, an embedded shortwave trough will track southeastward across the Southwest into the southern Rockies from Day 4/Monday into Day 5/Tuesday. At the same time, an amplified upper ridge will build over the eastern Pacific, favoring strengthening surface high pressure over the Intermountain West. This pattern will result in a strengthening offshore pressure gradient across southern CA (-6 to -8 mb LAX-DAG gradient), with moderate midlevel support across the area. Given reasonably good agreement in the development of single-digit to lower teens RH and strong/gusty east-northeasterly surface winds, 70-percent Critical probabilities have been introduced for the wind-prone Santa Ana corridor (much of Ventura County, northern/western Los Angeles County, and portions of northern San Bernardino County) for Day 4/Monday into Day 5/Tuesday. From Day 6/Wednesday into Day 7/Thursday, another shortwave trough should track southeastward across the Great Basin and Southwest, while an upstream ridge builds over the eastern Pacific. While noteworthy differences are evident among the medium-range guidance regarding this overall evolution, current indications are that surface high pressure will once again strengthen over the Intermountain West, favoring the potential for another dry offshore wind event across southern CA. 40-percent Critical probabilities have been added for Day 6/Wednesday into Day 7/Thursday, and higher probabilities could eventually be needed as the details become more clear. ..Weinman.. 01/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0359 PM CST Fri Jan 17 2025 Valid 191200Z - 251200Z ...Southern California... Within the base of a highly amplified, positive-tilt large-scale trough over the West, an embedded shortwave trough will track southeastward across the Southwest into the southern Rockies from Day 4/Monday into Day 5/Tuesday. At the same time, an amplified upper ridge will build over the eastern Pacific, favoring strengthening surface high pressure over the Intermountain West. This pattern will result in a strengthening offshore pressure gradient across southern CA (-6 to -8 mb LAX-DAG gradient), with moderate midlevel support across the area. Given reasonably good agreement in the development of single-digit to lower teens RH and strong/gusty east-northeasterly surface winds, 70-percent Critical probabilities have been introduced for the wind-prone Santa Ana corridor (much of Ventura County, northern/western Los Angeles County, and portions of northern San Bernardino County) for Day 4/Monday into Day 5/Tuesday. From Day 6/Wednesday into Day 7/Thursday, another shortwave trough should track southeastward across the Great Basin and Southwest, while an upstream ridge builds over the eastern Pacific. While noteworthy differences are evident among the medium-range guidance regarding this overall evolution, current indications are that surface high pressure will once again strengthen over the Intermountain West, favoring the potential for another dry offshore wind event across southern CA. 40-percent Critical probabilities have been added for Day 6/Wednesday into Day 7/Thursday, and higher probabilities could eventually be needed as the details become more clear. ..Weinman.. 01/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0359 PM CST Fri Jan 17 2025 Valid 191200Z - 251200Z ...Southern California... Within the base of a highly amplified, positive-tilt large-scale trough over the West, an embedded shortwave trough will track southeastward across the Southwest into the southern Rockies from Day 4/Monday into Day 5/Tuesday. At the same time, an amplified upper ridge will build over the eastern Pacific, favoring strengthening surface high pressure over the Intermountain West. This pattern will result in a strengthening offshore pressure gradient across southern CA (-6 to -8 mb LAX-DAG gradient), with moderate midlevel support across the area. Given reasonably good agreement in the development of single-digit to lower teens RH and strong/gusty east-northeasterly surface winds, 70-percent Critical probabilities have been introduced for the wind-prone Santa Ana corridor (much of Ventura County, northern/western Los Angeles County, and portions of northern San Bernardino County) for Day 4/Monday into Day 5/Tuesday. From Day 6/Wednesday into Day 7/Thursday, another shortwave trough should track southeastward across the Great Basin and Southwest, while an upstream ridge builds over the eastern Pacific. While noteworthy differences are evident among the medium-range guidance regarding this overall evolution, current indications are that surface high pressure will once again strengthen over the Intermountain West, favoring the potential for another dry offshore wind event across southern CA. 40-percent Critical probabilities have been added for Day 6/Wednesday into Day 7/Thursday, and higher probabilities could eventually be needed as the details become more clear. ..Weinman.. 01/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0359 PM CST Fri Jan 17 2025 Valid 191200Z - 251200Z ...Southern California... Within the base of a highly amplified, positive-tilt large-scale trough over the West, an embedded shortwave trough will track southeastward across the Southwest into the southern Rockies from Day 4/Monday into Day 5/Tuesday. At the same time, an amplified upper ridge will build over the eastern Pacific, favoring strengthening surface high pressure over the Intermountain West. This pattern will result in a strengthening offshore pressure gradient across southern CA (-6 to -8 mb LAX-DAG gradient), with moderate midlevel support across the area. Given reasonably good agreement in the development of single-digit to lower teens RH and strong/gusty east-northeasterly surface winds, 70-percent Critical probabilities have been introduced for the wind-prone Santa Ana corridor (much of Ventura County, northern/western Los Angeles County, and portions of northern San Bernardino County) for Day 4/Monday into Day 5/Tuesday. From Day 6/Wednesday into Day 7/Thursday, another shortwave trough should track southeastward across the Great Basin and Southwest, while an upstream ridge builds over the eastern Pacific. While noteworthy differences are evident among the medium-range guidance regarding this overall evolution, current indications are that surface high pressure will once again strengthen over the Intermountain West, favoring the potential for another dry offshore wind event across southern CA. 40-percent Critical probabilities have been added for Day 6/Wednesday into Day 7/Thursday, and higher probabilities could eventually be needed as the details become more clear. ..Weinman.. 01/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0359 PM CST Fri Jan 17 2025 Valid 191200Z - 251200Z ...Southern California... Within the base of a highly amplified, positive-tilt large-scale trough over the West, an embedded shortwave trough will track southeastward across the Southwest into the southern Rockies from Day 4/Monday into Day 5/Tuesday. At the same time, an amplified upper ridge will build over the eastern Pacific, favoring strengthening surface high pressure over the Intermountain West. This pattern will result in a strengthening offshore pressure gradient across southern CA (-6 to -8 mb LAX-DAG gradient), with moderate midlevel support across the area. Given reasonably good agreement in the development of single-digit to lower teens RH and strong/gusty east-northeasterly surface winds, 70-percent Critical probabilities have been introduced for the wind-prone Santa Ana corridor (much of Ventura County, northern/western Los Angeles County, and portions of northern San Bernardino County) for Day 4/Monday into Day 5/Tuesday. From Day 6/Wednesday into Day 7/Thursday, another shortwave trough should track southeastward across the Great Basin and Southwest, while an upstream ridge builds over the eastern Pacific. While noteworthy differences are evident among the medium-range guidance regarding this overall evolution, current indications are that surface high pressure will once again strengthen over the Intermountain West, favoring the potential for another dry offshore wind event across southern CA. 40-percent Critical probabilities have been added for Day 6/Wednesday into Day 7/Thursday, and higher probabilities could eventually be needed as the details become more clear. ..Weinman.. 01/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ...Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ...Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ..Moore.. 01/17/2025 .PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ...Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ...Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ...MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ...Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ...Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ..Moore.. 01/17/2025 .PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ...Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ...Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ...MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ...Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ...Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ..Moore.. 01/17/2025 .PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ...Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ...Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ...MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ...Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ...Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ..Moore.. 01/17/2025 .PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ...Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ...Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ...MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0150 PM CST Fri Jan 17 2025 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible from eastern Oklahoma into the Lower Mississippi/Tennessee Valleys and central Gulf Coast region this afternoon into early Saturday morning. ...20z Update... The previous forecast generally remains on track with only minor adjustments needed to the thunder line to reflect recent convective trends across central OK and trends in recent guidance. ...Central/Eastern OK... Sporadic lightning flashes have been noted across southwest to central OK over the past few hours - likely the result of strong synoptic ascent/mid-level cooling within the left-exit region of the upper jet over central TX (which is also evident by steady surface pressure falls across OK/KS). Occasional lightning flashes will remain possible through late afternoon and the evening hours as this activity spreads east/northeast into AR and far southern MO. ...Eastern AL/far western GA... Recent HRRR solutions continue to suggest a slight increase in coverage of weak thunderstorms during the 10-12 UTC period early Friday morning across far eastern AL. Forecast soundings from other guidance seem to corroborate this trend with 100-250 J/kg MUCAPE spreading into far western GA during this period. Given the convective signal and favorable environment, the thunder line was shifted east to account for low-end, early-morning thunderstorm potential. ..Moore.. 01/17/2025 .PREV DISCUSSION... /ISSUED 1028 AM CST Fri Jan 17 2025/ ...Synopsis... Satellite imagery shows a well-defined shortwave trough moving through the southern High Plains, with another shortwave visible farther southwest in the vicinity of the northern Baja Peninsula. An extensive fetch of westerly/southwesterly flow aloft exists throughout the bases of these waves, extending from the Baja Peninsula into the southern Plains. The northern shortwave is forecast to continue eastward across OK/north TX throughout the day. As it does, the flow aloft will strengthen to 90-110 kt over TX before spreading eastward/northeastward into the Lower MS Valley this evening and overnight. Recent surface analysis reveals a developing low near the KS/CO/OK border intersection, along the southern periphery of the surface troughing that extends across the central Plains. This low is expected to solidify over the next several hours as it moves along the Red River, with its adjacent warm sector shifting eastward as well. ...Eastern OK into AR... Persistent warm-air advection ahead of the approaching shortwave trough and attendant surface low may result in enough mid-level moistening to support a few elevated thunderstorms during the afternoon/early evening. Given the weak instability (i.e. MUCAPE less than 250 J/kg) and elevated nature of any convection that can form, severe storms are not expected. ...MS/AL... Strengthening warm-air advection is anticipated this evening and overnight across the Southeast as shortwave trough continues eastward and the strong jet max mentioned into the synopsis spreads into the region. This should promote an increase in buoyancy, with a resulting increase in thunderstorm coverage. Even so, low-level stability is expected to persist, with all of the buoyancy above 900-850mb. Strong vertical shear could result in a few more organized updrafts capable of producing small hail. However, elevated character to the thunderstorms and generally modest buoyancy (i.e. MUCAPE at and below 500 J/kg) should limit the overall severe potential. Read more