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MD 2219 CONCERNING HEAVY SNOW FOR SOUTHEAST COLORADO...FAR NORTHEAST NEW MEXICO...AND THE WESTERN OK PANHANDLE.
Mesoscale Discussion 2219 NWS Storm Prediction Center Norman OK 0623 AM CST Fri Nov 08 2024 Areas affected...southeast Colorado...far northeast New Mexico...and the western OK Panhandle. Concerning...Heavy snow Valid 081223Z - 081630Z SUMMARY...Heavy snow will develop across southeast Colorado and vicinity this morning. DISCUSSION...An upper-level low across New Mexico has started to become negatively tilted this morning. As this has occurred, a broad region of ascent has overspread the southern Plains, evidenced by widespread lightning activity. In addition, strong frontogenesis across the Texas Panhandle has resulted in a more focused region of ascent. The heavier precipitation associated with this enhanced area of UVV will migrate northwestward into the cold airmass across southeast Colorado over the next few hours. In addition, a easterly low-level jet, currently around 35 knots (per DDC VWP) and expected to strengthen to around 45 knots, will result in strengthening isentropic ascent. The combination of these factors will result in a favorable region across southeast Colorado and vicinity with snowfall rates of 1 to 2 inches per hour, likely starting between 13Z and 14Z. ..Bentley.. 11/08/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DDC...GLD...AMA...PUB...BOU...ABQ... LAT...LON 36440403 37140450 38360471 38920453 39550311 39530235 39220194 38040196 36830208 36290236 36020315 36440403 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Fri Nov 08 2024 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTH-CENTRAL TEXAS... ...SUMMARY... Severe-thunderstorm threat exists from north Texas to the Hill Country and parts of central/east Texas through this evening. The most focused tornado, damaging-wind and hail potential appears to be over north-central Texas. ...Synopsis... The mid/upper-level pattern features a closed, temporarily cut-off, synoptic-scale cyclone, initially centered over central NM. As a strong, basal shortwave trough pivots northeastward across eastern NM and the TX Panhandle today, the 500-mb low will shift east- northeastward toward CAO by 00Z. Overnight, the low should track north-northeastward, reaching the GLD vicinity by 12Z. Height falls should occur over central/north TX today, then becoming neutral to slightly rising overnight. The 11Z surface analysis showed a frontal-wave low near SWW, with a cold front south-southwestward between DRT-6R6. A warm front was drawn from the low through some rain-cooled air to near MWL, then east-southeastward over southern fringes of the Metroplex to between LFK-ESF. The low is expected to move northward to near the northeastern corner of the TX Panhandle by 00Z and occlude, while the occluded/cold front reaches western OK, north-central/central TX, to near LRD. The warm front should drift northward over north- central/northeast TX, with its progress slowed by increasing precip/convection to its north. By 12Z tomorrow, the low should get stacked with the 500-mb center over northwestern KS, with the cold front reaching east TX and the shelf waters off the TX Gulf Coast. Meanwhile, Hurricane Rafael is forecast to remain well-removed from land this period, moving generally westward over the central to west-central Gulf then slowing/meandering after this period. See NHC advisories for latest forecast track/intensity info on Rafael. ...North to central TX... An ongoing area of convection over parts of north TX and southern OK is expected to shift northward over increasingly elevated and less- unstable inflow parcels and weaken through midday. Meanwhile, closer to the cold front, scattered thunderstorms are expected to develop over the next several hours through early afternoon, evolving into a nearly solid convective band with embedded supercells and bow/LEWP formations possible. This activity should shift eastward over central and north TX through early evening, offering at least marginal potential for all severe hazards. Meanwhile, isolated to scattered thunderstorms are possible in the warm sector and along/north of the warm front. This activity should move northward to northeastward. Any sustained, relatively discrete cells with prolonged access to surface-based parcels in the warm sector, and especially interacting with the warm front, may rotate with a threat for all hazards (hail, damaging to severe gusts and mesoscale peak in tornado potential) also present. The associated theta-e/instability gradient is expected to align northwest/ southeast very near or even across the DFW Metroplex. This will yield an increased severe threat from north to south into more- unstable inflow air, and within the southern part of the relatively high-vorticity gradient itself. Given the superposition of these foci and the expected favorable parameter space, the north-central TX part of the outlook is being upgraded for all hazards this cycle. Upper 60s to low 70s F surface dewpoints already are present in the warm sector, and will shift north slowly, in step with the warm front, before the main north-south band overtakes the region. This should occur during the afternoon when low-level, warm-sector instability is maximized away from convection. Despite modest lapse rates aloft (manifest in mid/upper-level stable layers sampled by the 12Z FWD sounding), a northwestward-narrowing, triangular corridor of 1000-1500 J/kg peak MLCAPE is expected. Veering winds with height are forecast to continue, with hodograph curvature/size largest along the warm front, and enough deep shear (effective-shear magnitudes 35-45 kt in central/north TX, weakening southward and eastward) to support occasional supercell structures. Overnight, supportive large-scale ascent and the elevated LLJ each should shift northward away from the area, while the main band of convective- scale forcing shifts into east TX and weakens. ..Edwards/Bentley.. 11/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Fri Nov 08 2024 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTH-CENTRAL TEXAS... ...SUMMARY... Severe-thunderstorm threat exists from north Texas to the Hill Country and parts of central/east Texas through this evening. The most focused tornado, damaging-wind and hail potential appears to be over north-central Texas. ...Synopsis... The mid/upper-level pattern features a closed, temporarily cut-off, synoptic-scale cyclone, initially centered over central NM. As a strong, basal shortwave trough pivots northeastward across eastern NM and the TX Panhandle today, the 500-mb low will shift east- northeastward toward CAO by 00Z. Overnight, the low should track north-northeastward, reaching the GLD vicinity by 12Z. Height falls should occur over central/north TX today, then becoming neutral to slightly rising overnight. The 11Z surface analysis showed a frontal-wave low near SWW, with a cold front south-southwestward between DRT-6R6. A warm front was drawn from the low through some rain-cooled air to near MWL, then east-southeastward over southern fringes of the Metroplex to between LFK-ESF. The low is expected to move northward to near the northeastern corner of the TX Panhandle by 00Z and occlude, while the occluded/cold front reaches western OK, north-central/central TX, to near LRD. The warm front should drift northward over north- central/northeast TX, with its progress slowed by increasing precip/convection to its north. By 12Z tomorrow, the low should get stacked with the 500-mb center over northwestern KS, with the cold front reaching east TX and the shelf waters off the TX Gulf Coast. Meanwhile, Hurricane Rafael is forecast to remain well-removed from land this period, moving generally westward over the central to west-central Gulf then slowing/meandering after this period. See NHC advisories for latest forecast track/intensity info on Rafael. ...North to central TX... An ongoing area of convection over parts of north TX and southern OK is expected to shift northward over increasingly elevated and less- unstable inflow parcels and weaken through midday. Meanwhile, closer to the cold front, scattered thunderstorms are expected to develop over the next several hours through early afternoon, evolving into a nearly solid convective band with embedded supercells and bow/LEWP formations possible. This activity should shift eastward over central and north TX through early evening, offering at least marginal potential for all severe hazards. Meanwhile, isolated to scattered thunderstorms are possible in the warm sector and along/north of the warm front. This activity should move northward to northeastward. Any sustained, relatively discrete cells with prolonged access to surface-based parcels in the warm sector, and especially interacting with the warm front, may rotate with a threat for all hazards (hail, damaging to severe gusts and mesoscale peak in tornado potential) also present. The associated theta-e/instability gradient is expected to align northwest/ southeast very near or even across the DFW Metroplex. This will yield an increased severe threat from north to south into more- unstable inflow air, and within the southern part of the relatively high-vorticity gradient itself. Given the superposition of these foci and the expected favorable parameter space, the north-central TX part of the outlook is being upgraded for all hazards this cycle. Upper 60s to low 70s F surface dewpoints already are present in the warm sector, and will shift north slowly, in step with the warm front, before the main north-south band overtakes the region. This should occur during the afternoon when low-level, warm-sector instability is maximized away from convection. Despite modest lapse rates aloft (manifest in mid/upper-level stable layers sampled by the 12Z FWD sounding), a northwestward-narrowing, triangular corridor of 1000-1500 J/kg peak MLCAPE is expected. Veering winds with height are forecast to continue, with hodograph curvature/size largest along the warm front, and enough deep shear (effective-shear magnitudes 35-45 kt in central/north TX, weakening southward and eastward) to support occasional supercell structures. Overnight, supportive large-scale ascent and the elevated LLJ each should shift northward away from the area, while the main band of convective- scale forcing shifts into east TX and weakens. ..Edwards/Bentley.. 11/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Fri Nov 08 2024 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTH-CENTRAL TEXAS... ...SUMMARY... Severe-thunderstorm threat exists from north Texas to the Hill Country and parts of central/east Texas through this evening. The most focused tornado, damaging-wind and hail potential appears to be over north-central Texas. ...Synopsis... The mid/upper-level pattern features a closed, temporarily cut-off, synoptic-scale cyclone, initially centered over central NM. As a strong, basal shortwave trough pivots northeastward across eastern NM and the TX Panhandle today, the 500-mb low will shift east- northeastward toward CAO by 00Z. Overnight, the low should track north-northeastward, reaching the GLD vicinity by 12Z. Height falls should occur over central/north TX today, then becoming neutral to slightly rising overnight. The 11Z surface analysis showed a frontal-wave low near SWW, with a cold front south-southwestward between DRT-6R6. A warm front was drawn from the low through some rain-cooled air to near MWL, then east-southeastward over southern fringes of the Metroplex to between LFK-ESF. The low is expected to move northward to near the northeastern corner of the TX Panhandle by 00Z and occlude, while the occluded/cold front reaches western OK, north-central/central TX, to near LRD. The warm front should drift northward over north- central/northeast TX, with its progress slowed by increasing precip/convection to its north. By 12Z tomorrow, the low should get stacked with the 500-mb center over northwestern KS, with the cold front reaching east TX and the shelf waters off the TX Gulf Coast. Meanwhile, Hurricane Rafael is forecast to remain well-removed from land this period, moving generally westward over the central to west-central Gulf then slowing/meandering after this period. See NHC advisories for latest forecast track/intensity info on Rafael. ...North to central TX... An ongoing area of convection over parts of north TX and southern OK is expected to shift northward over increasingly elevated and less- unstable inflow parcels and weaken through midday. Meanwhile, closer to the cold front, scattered thunderstorms are expected to develop over the next several hours through early afternoon, evolving into a nearly solid convective band with embedded supercells and bow/LEWP formations possible. This activity should shift eastward over central and north TX through early evening, offering at least marginal potential for all severe hazards. Meanwhile, isolated to scattered thunderstorms are possible in the warm sector and along/north of the warm front. This activity should move northward to northeastward. Any sustained, relatively discrete cells with prolonged access to surface-based parcels in the warm sector, and especially interacting with the warm front, may rotate with a threat for all hazards (hail, damaging to severe gusts and mesoscale peak in tornado potential) also present. The associated theta-e/instability gradient is expected to align northwest/ southeast very near or even across the DFW Metroplex. This will yield an increased severe threat from north to south into more- unstable inflow air, and within the southern part of the relatively high-vorticity gradient itself. Given the superposition of these foci and the expected favorable parameter space, the north-central TX part of the outlook is being upgraded for all hazards this cycle. Upper 60s to low 70s F surface dewpoints already are present in the warm sector, and will shift north slowly, in step with the warm front, before the main north-south band overtakes the region. This should occur during the afternoon when low-level, warm-sector instability is maximized away from convection. Despite modest lapse rates aloft (manifest in mid/upper-level stable layers sampled by the 12Z FWD sounding), a northwestward-narrowing, triangular corridor of 1000-1500 J/kg peak MLCAPE is expected. Veering winds with height are forecast to continue, with hodograph curvature/size largest along the warm front, and enough deep shear (effective-shear magnitudes 35-45 kt in central/north TX, weakening southward and eastward) to support occasional supercell structures. Overnight, supportive large-scale ascent and the elevated LLJ each should shift northward away from the area, while the main band of convective- scale forcing shifts into east TX and weakens. ..Edwards/Bentley.. 11/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Fri Nov 08 2024 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTH-CENTRAL TEXAS... ...SUMMARY... Severe-thunderstorm threat exists from north Texas to the Hill Country and parts of central/east Texas through this evening. The most focused tornado, damaging-wind and hail potential appears to be over north-central Texas. ...Synopsis... The mid/upper-level pattern features a closed, temporarily cut-off, synoptic-scale cyclone, initially centered over central NM. As a strong, basal shortwave trough pivots northeastward across eastern NM and the TX Panhandle today, the 500-mb low will shift east- northeastward toward CAO by 00Z. Overnight, the low should track north-northeastward, reaching the GLD vicinity by 12Z. Height falls should occur over central/north TX today, then becoming neutral to slightly rising overnight. The 11Z surface analysis showed a frontal-wave low near SWW, with a cold front south-southwestward between DRT-6R6. A warm front was drawn from the low through some rain-cooled air to near MWL, then east-southeastward over southern fringes of the Metroplex to between LFK-ESF. The low is expected to move northward to near the northeastern corner of the TX Panhandle by 00Z and occlude, while the occluded/cold front reaches western OK, north-central/central TX, to near LRD. The warm front should drift northward over north- central/northeast TX, with its progress slowed by increasing precip/convection to its north. By 12Z tomorrow, the low should get stacked with the 500-mb center over northwestern KS, with the cold front reaching east TX and the shelf waters off the TX Gulf Coast. Meanwhile, Hurricane Rafael is forecast to remain well-removed from land this period, moving generally westward over the central to west-central Gulf then slowing/meandering after this period. See NHC advisories for latest forecast track/intensity info on Rafael. ...North to central TX... An ongoing area of convection over parts of north TX and southern OK is expected to shift northward over increasingly elevated and less- unstable inflow parcels and weaken through midday. Meanwhile, closer to the cold front, scattered thunderstorms are expected to develop over the next several hours through early afternoon, evolving into a nearly solid convective band with embedded supercells and bow/LEWP formations possible. This activity should shift eastward over central and north TX through early evening, offering at least marginal potential for all severe hazards. Meanwhile, isolated to scattered thunderstorms are possible in the warm sector and along/north of the warm front. This activity should move northward to northeastward. Any sustained, relatively discrete cells with prolonged access to surface-based parcels in the warm sector, and especially interacting with the warm front, may rotate with a threat for all hazards (hail, damaging to severe gusts and mesoscale peak in tornado potential) also present. The associated theta-e/instability gradient is expected to align northwest/ southeast very near or even across the DFW Metroplex. This will yield an increased severe threat from north to south into more- unstable inflow air, and within the southern part of the relatively high-vorticity gradient itself. Given the superposition of these foci and the expected favorable parameter space, the north-central TX part of the outlook is being upgraded for all hazards this cycle. Upper 60s to low 70s F surface dewpoints already are present in the warm sector, and will shift north slowly, in step with the warm front, before the main north-south band overtakes the region. This should occur during the afternoon when low-level, warm-sector instability is maximized away from convection. Despite modest lapse rates aloft (manifest in mid/upper-level stable layers sampled by the 12Z FWD sounding), a northwestward-narrowing, triangular corridor of 1000-1500 J/kg peak MLCAPE is expected. Veering winds with height are forecast to continue, with hodograph curvature/size largest along the warm front, and enough deep shear (effective-shear magnitudes 35-45 kt in central/north TX, weakening southward and eastward) to support occasional supercell structures. Overnight, supportive large-scale ascent and the elevated LLJ each should shift northward away from the area, while the main band of convective- scale forcing shifts into east TX and weakens. ..Edwards/Bentley.. 11/08/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0652 AM CST Fri Nov 08 2024 Valid 081300Z - 091200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER NORTH-CENTRAL TEXAS... ...SUMMARY... Severe-thunderstorm threat exists from north Texas to the Hill Country and parts of central/east Texas through this evening. The most focused tornado, damaging-wind and hail potential appears to be over north-central Texas. ...Synopsis... The mid/upper-level pattern features a closed, temporarily cut-off, synoptic-scale cyclone, initially centered over central NM. As a strong, basal shortwave trough pivots northeastward across eastern NM and the TX Panhandle today, the 500-mb low will shift east- northeastward toward CAO by 00Z. Overnight, the low should track north-northeastward, reaching the GLD vicinity by 12Z. Height falls should occur over central/north TX today, then becoming neutral to slightly rising overnight. The 11Z surface analysis showed a frontal-wave low near SWW, with a cold front south-southwestward between DRT-6R6. A warm front was drawn from the low through some rain-cooled air to near MWL, then east-southeastward over southern fringes of the Metroplex to between LFK-ESF. The low is expected to move northward to near the northeastern corner of the TX Panhandle by 00Z and occlude, while the occluded/cold front reaches western OK, north-central/central TX, to near LRD. The warm front should drift northward over north- central/northeast TX, with its progress slowed by increasing precip/convection to its north. By 12Z tomorrow, the low should get stacked with the 500-mb center over northwestern KS, with the cold front reaching east TX and the shelf waters off the TX Gulf Coast. Meanwhile, Hurricane Rafael is forecast to remain well-removed from land this period, moving generally westward over the central to west-central Gulf then slowing/meandering after this period. See NHC advisories for latest forecast track/intensity info on Rafael. ...North to central TX... An ongoing area of convection over parts of north TX and southern OK is expected to shift northward over increasingly elevated and less- unstable inflow parcels and weaken through midday. Meanwhile, closer to the cold front, scattered thunderstorms are expected to develop over the next several hours through early afternoon, evolving into a nearly solid convective band with embedded supercells and bow/LEWP formations possible. This activity should shift eastward over central and north TX through early evening, offering at least marginal potential for all severe hazards. Meanwhile, isolated to scattered thunderstorms are possible in the warm sector and along/north of the warm front. This activity should move northward to northeastward. Any sustained, relatively discrete cells with prolonged access to surface-based parcels in the warm sector, and especially interacting with the warm front, may rotate with a threat for all hazards (hail, damaging to severe gusts and mesoscale peak in tornado potential) also present. The associated theta-e/instability gradient is expected to align northwest/ southeast very near or even across the DFW Metroplex. This will yield an increased severe threat from north to south into more- unstable inflow air, and within the southern part of the relatively high-vorticity gradient itself. Given the superposition of these foci and the expected favorable parameter space, the north-central TX part of the outlook is being upgraded for all hazards this cycle. Upper 60s to low 70s F surface dewpoints already are present in the warm sector, and will shift north slowly, in step with the warm front, before the main north-south band overtakes the region. This should occur during the afternoon when low-level, warm-sector instability is maximized away from convection. Despite modest lapse rates aloft (manifest in mid/upper-level stable layers sampled by the 12Z FWD sounding), a northwestward-narrowing, triangular corridor of 1000-1500 J/kg peak MLCAPE is expected. Veering winds with height are forecast to continue, with hodograph curvature/size largest along the warm front, and enough deep shear (effective-shear magnitudes 35-45 kt in central/north TX, weakening southward and eastward) to support occasional supercell structures. Overnight, supportive large-scale ascent and the elevated LLJ each should shift northward away from the area, while the main band of convective- scale forcing shifts into east TX and weakens. ..Edwards/Bentley.. 11/08/2024 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0239 AM CST Fri Nov 08 2024 Valid 111200Z - 161200Z ...DISCUSSION... Guidance consensus continues to indicate a broad upper trough progressing into the West early next week, and then reaching the central states around mid-week. Nevertheless, 00Z ensemble spread remains large with both the degree of trough amplification and spatiotemporal details. The GEFS has trended towards less amplification over the West, instead favoring later over the Upper Midwest. The ECMWF ensemble mean favors greater amplification over the West, which is supported by its deterministic parent and UKMET/CMC guidance. Run-to-run continuity is poor with the degree/location of cyclogenesis east of the Rockies. With greater confidence in a surface ridge holding across the northern Gulf, modified moisture return appears more likely to be limited in the southern to central Great Plains through D5/Tuesday. The breadth of the warm-moist sector will probably enlarge by D6/Wednesday, yielding concern for some severe potential over the south-central states. But given poor predictability of synoptic-scale details, consideration of an area is premature. Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0153 AM CST Fri Nov 08 2024 Valid 101200Z - 111200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe storms are not expected on Sunday or Sunday night. ...Synopsis... A dampening shortwave trough will progress from the Upper Midwest across the Great Lakes. The trailing occluded/cold/quasi-stationary front arcing southwest, from the attendant surface low moving into southeast Canada, will serve as a focus for weak thunder activity. Poor mid-level lapse rates will limit coverage, from the Lower OH Valley southwestward across the Lower MS to Sabine Valleys. Isolated thunderstorms are possible over far south FL by late afternoon into Sunday night as low-level moisture increases from the southeast. 10 percent thunder probabilities may reach coastal WA/OR by 12Z Monday as a northeast Pacific shortwave trough approaches. ...Coastal LA... 00Z ECMWF ensemble depicts increasing spread in the evolution of TC Rafael by early Sunday as the cyclone weakens. A small percentage support more of a northerly movement, similar to deterministic NCEP/CMC guidance. But the vast majority of the ECMWF ensemble members, along with the UKMET, support the favored NHC forecast. For now, TC-tornado potential appears likely to remain negligible. ..Grams.. 11/08/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0143 AM CST Fri Nov 08 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low across the CONUS on Saturday. A deepening trough will bring widespread rain across much of the central/southern Plains. Elsewhere, dry conditions will continue across southern California and across portions of New England. Both of these regions will be under building high pressure, keeping winds mostly light and fire concerns low. ..Thornton.. 11/08/2024 ...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 0143 AM CST Fri Nov 08 2024 Valid 091200Z - 101200Z ...NO CRITICAL AREAS... ...Synopsis... Fire weather concerns will be low across the CONUS on Saturday. A deepening trough will bring widespread rain across much of the central/southern Plains. Elsewhere, dry conditions will continue across southern California and across portions of New England. Both of these regions will be under building high pressure, keeping winds mostly light and fire concerns low. ..Thornton.. 11/08/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more