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MD 0766 CONCERNING TORNADO WATCH 211... FOR WESTERN KANSAS INTO WESTERN NEBRASKA
Mesoscale Discussion 0766 NWS Storm Prediction Center Norman OK 0349 PM CDT Thu May 11 2023 Areas affected...western Kansas into western Nebraska Concerning...Tornado Watch 211... Valid 112049Z - 112215Z The severe weather threat for Tornado Watch 211 continues. SUMMARY...The severe risk persists over western Kansas, and may increase into western Nebraska with time. An additional watch could eventually be needed north of the existing watch 211, depending on storm trends. DISCUSSION...Bands of thunderstorms persist north of the surface low and ahead of midlevel cooling with the upper trough. Strong boundary layer easterlies continue to push moisture westward across northwest KS and into western NE toward an inverted surface trough. The easterly winds are also helping warm advection in general, as heating continues upstream from northern KS into central NE. Low-level shear is sufficient for a weak/brief tornado threat with 0-1 values around 100 m2/s2. As such, given the time of day, an additional watch could be needed into more of NE and perhaps north-central KS as the storms develop in that direction. In addition, a plume of steep lapse rates pushing into southwest KS ahead of the vort max could lead to locally severe gusts with activity developing over southeast CO currently. ..Jewell.. 05/11/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ICT...GID...LBF...DDC...GLD...BOU... LAT...LON 37489984 38120045 38940113 39630181 40110207 40640240 42030260 42630260 42720222 42540198 41680123 41080073 40340003 39099920 38369891 37559923 37489984 Read more

WW 0210 Status Updates
STATUS REPORT ON WW 210 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..05/11/23 ATTN...WFO...JAN...SHV...LCH... STATUS REPORT FOR WT 210 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC009-025-029-079-115-112140- LA . LOUISIANA PARISHES INCLUDED ARE AVOYELLES CATAHOULA CONCORDIA RAPIDES VERNON MSC001-021-063-149-112140- MS . MISSISSIPPI COUNTIES INCLUDED ARE ADAMS CLAIBORNE JEFFERSON WARREN THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 0210 Status Updates
STATUS REPORT ON WW 210 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..BENTLEY..05/11/23 ATTN...WFO...JAN...SHV...LCH... STATUS REPORT FOR WT 210 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC009-025-029-079-115-112140- LA . LOUISIANA PARISHES INCLUDED ARE AVOYELLES CATAHOULA CONCORDIA RAPIDES VERNON MSC001-021-063-149-112140- MS . MISSISSIPPI COUNTIES INCLUDED ARE ADAMS CLAIBORNE JEFFERSON WARREN THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. Read more

WW 210 TORNADO AR LA MS 111425Z - 112200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 210 NWS Storm Prediction Center Norman OK 925 AM CDT Thu May 11 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Southeast Arkansas Northern and Central Louisiana Western Mississippi * Effective this Thursday morning and afternoon from 925 AM until 500 PM CDT. * Primary threats include... A couple tornadoes possible Scattered damaging wind gusts to 65 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...An environment supportive of supercells capable of a few mostly short-lived tornadoes is expected to continue into the afternoon across a broad portion of the ArkLaMiss region, with damaging wind potential also potentially increasing into the afternoon. The tornado watch area is approximately along and 65 statute miles east and west of a line from 30 miles east of Fort Polk LA to 55 miles north northeast of Monroe LA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 55 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24020. ...Guyer Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Thu May 11 2023 Valid 112000Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS KANSAS INTO SOUTHERN OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST LOUISIANA INTO SOUTHERN MISSISSIPPI... ...SUMMARY... Scattered severe thunderstorms remain possible into this evening across parts of the Great Plains centered on Kansas and Oklahoma. The greatest threat for a couple strong tornadic supercells should exist across central and southern Oklahoma between 5 to 9 PM CDT. Isolated severe storms including a couple of tornadoes and damaging winds are also expected across the Lower Mississippi Valley. ...Kansas into Oklahoma... The severe threat continues across much of KS where an arcing band of convection has developed from northwest to southern/southwestern KS. Reflectivity/velocity data from regional radars show some cells taking on supercellular characteristics with persistent mesocyclones, including at least one reported tornado. So while the overall kinematic environment appears somewhat marginal based on latest RAP mesoanalyses (effective SRH values 100 m2/s2 or less), the environment is conducive for organized convection, and should remain so through the evening as the nocturnal jet strengthens after 00 UTC. Further south, a residual cold pool across central to northern OK from early-morning convection has introduced considerable uncertainty into the severe weather potential. While an intense storm or two remains possible across north-central OK to southern KS, confidence in the tornado potential has diminished due to the detrimental influence of the cold pool on low-level thermodynamics and questions regarding adequate air mass recovery into the evening. The 10% tornado risk probabilities have been bifurcated to reflect where confidence in the tornado threat is highest. See MCD #764 for additional information on recent observed trends and forecast expectations for southern/central OK. ...Lower MS Valley... An organized, but outflow-dominant, MCS has developed over the past several hours and continues to propagate eastward into southern MS. Latest radar trends and surface observations/analyses suggest that this feature may begin to take on a more southeasterly track through the late afternoon/early evening along a diffuse buoyancy/theta-e gradient into southeast MS. Although the system appears to be outflow dominant, damaging winds remain probable given recent measured wind speeds above 50 mph. ..Moore/Leitman.. 05/11/2023 .PREV DISCUSSION... /ISSUED 1141 AM CDT Thu May 11 2023/ ...Southern/Central Great Plains... A cluster of storms continues to persist at late morning across south-central Oklahoma, and remain somewhat strong in proximity to the Red River, with other more recent/initial arcing bands of thunderstorm development in a separate regime across southeast Colorado. This is occurring near/ahead of the largely stacked cyclone centered near the Raton Mesa vicinity of northeast New Mexico/southeast Colorado. 12z upper-air analysis features of a zone of stronger mid/high-level winds across the south-central High Plains immediately preceding this cyclone, while winds aloft (especially high level) are otherwise relatively weak across the region. A moist boundary layer is noted across the south-central High Plains, with relatively high PW values and 12+ C 850mb dewpoints observed at both Dodge City and Amarillo per 12z RAOBs, a northwestward extension of the rich low-level moist axis that otherwise extends across the middle part of Texas. The surface cyclone is expected to deepen as it develops toward southwest Kansas today, with the dryline mixing into western Oklahoma and arcing south-southwest into the Edwards Plateau. A north/south-oriented inverted trough/quasi-stationary front will extend north to the western Dakotas. Multiple corridors of increasing severe potential are expected this afternoon. As focused ascent overspreads southeast Colorado into western Kansas, low-topped supercells will become increasingly probable midday to early afternoon within a marginally buoyant environment initially. A smaller area of supercell development may also form in the wake of this activity near the Colorado/Kansas border later in the afternoon and yield a persistent severe threat into early evening. Farther south, the aforementioned early day persistent cluster of storms across south-central Oklahoma casts some uncertainty, particularly in regards to its north, with potential ramifications for areas such as northern Oklahoma/far southern Kansas with the possibility of somewhat more isolated storms. A volatile supercell environment should still evolve to the west of this cluster and ahead of the dryline, especially across southwest into west-central/south-central Oklahoma. A pronounced gradient in MLCAPE is likely by late afternoon to early evening as the most robust boundary-layer heating post-dryline occurs in Texas, while a plume of richer moisture advects north ahead of it. This should support MLCAPE approaching 1500 J/kg near the OK/KS border to around 3500 J/kg along the Red River. While a mid-level jetlet over the southern High Plains will be in an overall weakening state, its favorably timed eastward translation across the dryline should support sustained supercells. Upper-level wind fields will weaken with height and the bulk of hodograph structure will consist of enlarged curvature from 0-3 km. This suggests supercells should tend towards an HP character with a slow-moving cluster type evolution. A moderate increase in low-level flow early this evening could support a strong tornado risk, especially across southern/central Oklahoma with the most intense supercells. A small MCS/embedded supercell cluster will probably persist into eastern Oklahoma before eventually weakening during the overnight. ...ArkLaMiss/Lower Mississippi Valley to Southeast... The environment that potentially produced a couple of tornadoes this morning across northern Louisiana is expected to generally persist eastward across the ArkLaMiss into the afternoon, with a continued potential for mostly brief tornadoes. There will also likely be some increase in damaging wind potential as storm mergers occur and the downstream boundary layer warms and destabilizes. Other more localized/episodic strong to severe storms capable of damaging winds are possible farther east into Alabama, southwest Georgia, and northern Florida, primarily before sunset. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0253 PM CDT Thu May 11 2023 Valid 112000Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS KANSAS INTO SOUTHERN OKLAHOMA... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS SOUTHEAST LOUISIANA INTO SOUTHERN MISSISSIPPI... ...SUMMARY... Scattered severe thunderstorms remain possible into this evening across parts of the Great Plains centered on Kansas and Oklahoma. The greatest threat for a couple strong tornadic supercells should exist across central and southern Oklahoma between 5 to 9 PM CDT. Isolated severe storms including a couple of tornadoes and damaging winds are also expected across the Lower Mississippi Valley. ...Kansas into Oklahoma... The severe threat continues across much of KS where an arcing band of convection has developed from northwest to southern/southwestern KS. Reflectivity/velocity data from regional radars show some cells taking on supercellular characteristics with persistent mesocyclones, including at least one reported tornado. So while the overall kinematic environment appears somewhat marginal based on latest RAP mesoanalyses (effective SRH values 100 m2/s2 or less), the environment is conducive for organized convection, and should remain so through the evening as the nocturnal jet strengthens after 00 UTC. Further south, a residual cold pool across central to northern OK from early-morning convection has introduced considerable uncertainty into the severe weather potential. While an intense storm or two remains possible across north-central OK to southern KS, confidence in the tornado potential has diminished due to the detrimental influence of the cold pool on low-level thermodynamics and questions regarding adequate air mass recovery into the evening. The 10% tornado risk probabilities have been bifurcated to reflect where confidence in the tornado threat is highest. See MCD #764 for additional information on recent observed trends and forecast expectations for southern/central OK. ...Lower MS Valley... An organized, but outflow-dominant, MCS has developed over the past several hours and continues to propagate eastward into southern MS. Latest radar trends and surface observations/analyses suggest that this feature may begin to take on a more southeasterly track through the late afternoon/early evening along a diffuse buoyancy/theta-e gradient into southeast MS. Although the system appears to be outflow dominant, damaging winds remain probable given recent measured wind speeds above 50 mph. ..Moore/Leitman.. 05/11/2023 .PREV DISCUSSION... /ISSUED 1141 AM CDT Thu May 11 2023/ ...Southern/Central Great Plains... A cluster of storms continues to persist at late morning across south-central Oklahoma, and remain somewhat strong in proximity to the Red River, with other more recent/initial arcing bands of thunderstorm development in a separate regime across southeast Colorado. This is occurring near/ahead of the largely stacked cyclone centered near the Raton Mesa vicinity of northeast New Mexico/southeast Colorado. 12z upper-air analysis features of a zone of stronger mid/high-level winds across the south-central High Plains immediately preceding this cyclone, while winds aloft (especially high level) are otherwise relatively weak across the region. A moist boundary layer is noted across the south-central High Plains, with relatively high PW values and 12+ C 850mb dewpoints observed at both Dodge City and Amarillo per 12z RAOBs, a northwestward extension of the rich low-level moist axis that otherwise extends across the middle part of Texas. The surface cyclone is expected to deepen as it develops toward southwest Kansas today, with the dryline mixing into western Oklahoma and arcing south-southwest into the Edwards Plateau. A north/south-oriented inverted trough/quasi-stationary front will extend north to the western Dakotas. Multiple corridors of increasing severe potential are expected this afternoon. As focused ascent overspreads southeast Colorado into western Kansas, low-topped supercells will become increasingly probable midday to early afternoon within a marginally buoyant environment initially. A smaller area of supercell development may also form in the wake of this activity near the Colorado/Kansas border later in the afternoon and yield a persistent severe threat into early evening. Farther south, the aforementioned early day persistent cluster of storms across south-central Oklahoma casts some uncertainty, particularly in regards to its north, with potential ramifications for areas such as northern Oklahoma/far southern Kansas with the possibility of somewhat more isolated storms. A volatile supercell environment should still evolve to the west of this cluster and ahead of the dryline, especially across southwest into west-central/south-central Oklahoma. A pronounced gradient in MLCAPE is likely by late afternoon to early evening as the most robust boundary-layer heating post-dryline occurs in Texas, while a plume of richer moisture advects north ahead of it. This should support MLCAPE approaching 1500 J/kg near the OK/KS border to around 3500 J/kg along the Red River. While a mid-level jetlet over the southern High Plains will be in an overall weakening state, its favorably timed eastward translation across the dryline should support sustained supercells. Upper-level wind fields will weaken with height and the bulk of hodograph structure will consist of enlarged curvature from 0-3 km. This suggests supercells should tend towards an HP character with a slow-moving cluster type evolution. A moderate increase in low-level flow early this evening could support a strong tornado risk, especially across southern/central Oklahoma with the most intense supercells. A small MCS/embedded supercell cluster will probably persist into eastern Oklahoma before eventually weakening during the overnight. ...ArkLaMiss/Lower Mississippi Valley to Southeast... The environment that potentially produced a couple of tornadoes this morning across northern Louisiana is expected to generally persist eastward across the ArkLaMiss into the afternoon, with a continued potential for mostly brief tornadoes. There will also likely be some increase in damaging wind potential as storm mergers occur and the downstream boundary layer warms and destabilizes. Other more localized/episodic strong to severe storms capable of damaging winds are possible farther east into Alabama, southwest Georgia, and northern Florida, primarily before sunset. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0113 PM CDT Thu May 11 2023 Valid 121200Z - 131200Z No changes to the ongoing forecast. ..Wendt.. 05/11/2023 .PREV DISCUSSION... /ISSUED 0112 AM CDT Thu May 11 2023/ ...Synopsis... The mid-level trough over the southern Plains is forecast to continue to drift northeastward and slowly weaken through Friday. Trialing the surface low, a cold front will move in from the northwest ushering in a cooler and more moist air mass across the Rockies and southern High Plains. Widespread precipitation is also expected starting Friday across the High Plains potentially limiting area fuels. With winds aloft weakening, increasing RH, and more limited fuels, widespread fire-weather concerns are not anticipated. ...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 0113 PM CDT Thu May 11 2023 Valid 121200Z - 131200Z No changes to the ongoing forecast. ..Wendt.. 05/11/2023 .PREV DISCUSSION... /ISSUED 0112 AM CDT Thu May 11 2023/ ...Synopsis... The mid-level trough over the southern Plains is forecast to continue to drift northeastward and slowly weaken through Friday. Trialing the surface low, a cold front will move in from the northwest ushering in a cooler and more moist air mass across the Rockies and southern High Plains. Widespread precipitation is also expected starting Friday across the High Plains potentially limiting area fuels. With winds aloft weakening, increasing RH, and more limited fuels, widespread fire-weather concerns are not anticipated. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Thu May 11 2023 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THE MID-MISSOURI RIVER VALLEY AND ACROSS THE SOUTHERN PLAINS TO THE RIO GRANDE VALLEY... ...SUMMARY... Strong/severe storms are expected to begin during the afternoon, across a broad area extending from the Mid-Missouri Valley southward to the Rio Grande Valley. Very large hail and damaging wind gusts will likely be the primary severe threats over the southern half of the area into the overnight hours, while damaging winds and hail, and a couple of tornadoes, will be possible across the Mid Missouri Valley area through the evening. ...Synopsis... The upper-level wave currently migrating northeast across western KS is forecast to continue to the northeast over the next 48 hours, reaching the mid-MO Valley by mid/late afternoon. In general, this feature, and an attendant surface low, will de-amplify through the period with an associated weakening of mid/upper-level flow outside of the mid-MO Valley. A surface trough/dryline should be draped from eastern NE southward through central KS/OK and into TX by late afternoon and will act as a foci for convective initiation. To the south, mid-morning water-vapor imagery depicts a shortwave trough approaching Baja CA. This wave should reach the Big Bend region by tomorrow afternoon/evening, and will augment orographically-driven ascent, fostering scattered thunderstorm development along the Rio Grande. ...Mid Missouri River Valley... A reservoir of low 60s dewpoints is noted in morning surface observations across much of the central Plains. Persistent south/southeasterly flow over the next 36 hours ahead of the approaching surface low will maintain some poleward moisture advection, and some solutions suggest dewpoints may reach the mid-60s. Regardless, cool temperatures aloft associated with the upper-low will result in mid-level lapse rates near 7-7.5 C/km. Combined with the aforementioned low-level moisture, this should support MLCAPE values approaching 2000-3000 J/kg by late afternoon. Given the lack of an appreciable EML, diurnal warming should erode any mixed-layer inhibition and allow convective initiation along the surface trough/dryline. Initial convection will likely manifest as an arching band of discrete/semi-discrete cells with an attendant hail/wind risk. A few tornadoes are also possible given veered low-level winds and modest effective SRH ahead of the dryline. Upscale growth into one or more organized clusters is probable through the evening given deep-layer meridional flow oriented largely along the boundary - especially across southeast NE into adjacent areas of IA, KS, and MO. A corridor of several, perhaps longer-lived, supercells may emerge across portions of northeast NE where deep-layer shear orientations will be nearly orthogonal to the dryline. If this scenario occurs the large hail/tornado threat may be locally maximized. A significant hail area has been introduced to reflect the conditional nature of the threat. However, confidence in the spatial extent of this threat appears too limited in this forecast cycle for a categorical upgrade. ...Central OK to the Rio Grande... A migratory dryline should be draped from northeast KS through central OK and into western TX by late afternoon, though forecast uncertainty remains somewhat high in the exact placement of this feature by peak heating. This region will be well displaced from the stronger forcing for ascent to the north, but forecast soundings suggest residence time within the dryline circulation and strong diurnal warming will be sufficient for convective initiation along the boundary. Additional cells will likely develop off the terrain in northern Mexico, and should migrate east/northeast into southern TX. High-quality moisture return (dewpoints into the low 70s), coupled with temperatures in the low 80s will support strong buoyancy (MLCAPE near 4000 J/kg in some guidance). Mid and upper-level winds are forecast to be modest, only around 25-30 knots, but may be adequate for storm organization - especially across central/southern OK. Further south towards the Rio Grande, hodograph structure becomes more nebulous amid weak flow aloft, but the combination of ample buoyancy and a deep, well-mixed boundary layer will support the potential for strong downburst winds and large hail with initial updraft pulses. Through the evening, initially discrete/semi-discrete cells will likely see cold pool amalgamation/consolidation, resulting in upscale growth into a loosely organized, cold-pool driven MCS. As this occurs, the potential for severe winds should increase across central TX. The strengthening of a low-level jet over southern TX may allow for MCS maintenance overnight to near the TX Coastal Plain by 12 UTC Saturday (though the intensity of the MCS with eastward extent remains uncertain). ..Moore/Leitman.. 05/11/2023 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1223 PM CDT Thu May 11 2023 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THE MID-MISSOURI RIVER VALLEY AND ACROSS THE SOUTHERN PLAINS TO THE RIO GRANDE VALLEY... ...SUMMARY... Strong/severe storms are expected to begin during the afternoon, across a broad area extending from the Mid-Missouri Valley southward to the Rio Grande Valley. Very large hail and damaging wind gusts will likely be the primary severe threats over the southern half of the area into the overnight hours, while damaging winds and hail, and a couple of tornadoes, will be possible across the Mid Missouri Valley area through the evening. ...Synopsis... The upper-level wave currently migrating northeast across western KS is forecast to continue to the northeast over the next 48 hours, reaching the mid-MO Valley by mid/late afternoon. In general, this feature, and an attendant surface low, will de-amplify through the period with an associated weakening of mid/upper-level flow outside of the mid-MO Valley. A surface trough/dryline should be draped from eastern NE southward through central KS/OK and into TX by late afternoon and will act as a foci for convective initiation. To the south, mid-morning water-vapor imagery depicts a shortwave trough approaching Baja CA. This wave should reach the Big Bend region by tomorrow afternoon/evening, and will augment orographically-driven ascent, fostering scattered thunderstorm development along the Rio Grande. ...Mid Missouri River Valley... A reservoir of low 60s dewpoints is noted in morning surface observations across much of the central Plains. Persistent south/southeasterly flow over the next 36 hours ahead of the approaching surface low will maintain some poleward moisture advection, and some solutions suggest dewpoints may reach the mid-60s. Regardless, cool temperatures aloft associated with the upper-low will result in mid-level lapse rates near 7-7.5 C/km. Combined with the aforementioned low-level moisture, this should support MLCAPE values approaching 2000-3000 J/kg by late afternoon. Given the lack of an appreciable EML, diurnal warming should erode any mixed-layer inhibition and allow convective initiation along the surface trough/dryline. Initial convection will likely manifest as an arching band of discrete/semi-discrete cells with an attendant hail/wind risk. A few tornadoes are also possible given veered low-level winds and modest effective SRH ahead of the dryline. Upscale growth into one or more organized clusters is probable through the evening given deep-layer meridional flow oriented largely along the boundary - especially across southeast NE into adjacent areas of IA, KS, and MO. A corridor of several, perhaps longer-lived, supercells may emerge across portions of northeast NE where deep-layer shear orientations will be nearly orthogonal to the dryline. If this scenario occurs the large hail/tornado threat may be locally maximized. A significant hail area has been introduced to reflect the conditional nature of the threat. However, confidence in the spatial extent of this threat appears too limited in this forecast cycle for a categorical upgrade. ...Central OK to the Rio Grande... A migratory dryline should be draped from northeast KS through central OK and into western TX by late afternoon, though forecast uncertainty remains somewhat high in the exact placement of this feature by peak heating. This region will be well displaced from the stronger forcing for ascent to the north, but forecast soundings suggest residence time within the dryline circulation and strong diurnal warming will be sufficient for convective initiation along the boundary. Additional cells will likely develop off the terrain in northern Mexico, and should migrate east/northeast into southern TX. High-quality moisture return (dewpoints into the low 70s), coupled with temperatures in the low 80s will support strong buoyancy (MLCAPE near 4000 J/kg in some guidance). Mid and upper-level winds are forecast to be modest, only around 25-30 knots, but may be adequate for storm organization - especially across central/southern OK. Further south towards the Rio Grande, hodograph structure becomes more nebulous amid weak flow aloft, but the combination of ample buoyancy and a deep, well-mixed boundary layer will support the potential for strong downburst winds and large hail with initial updraft pulses. Through the evening, initially discrete/semi-discrete cells will likely see cold pool amalgamation/consolidation, resulting in upscale growth into a loosely organized, cold-pool driven MCS. As this occurs, the potential for severe winds should increase across central TX. The strengthening of a low-level jet over southern TX may allow for MCS maintenance overnight to near the TX Coastal Plain by 12 UTC Saturday (though the intensity of the MCS with eastward extent remains uncertain). ..Moore/Leitman.. 05/11/2023 Read more

No Mesoscale Discussions are in effect as of Wed May 10 22:00:06 UTC 2023.

WW 0207 Status Updates
STATUS REPORT ON WW 207 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..05/10/23 ATTN...WFO...BOU...GLD...PUB...LBF... STATUS REPORT FOR WT 207 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC001-005-017-031-035-039-041-063-073-075-087-095-115-119-121- 123-125-102140- CO . COLORADO COUNTIES INCLUDED ARE ADAMS ARAPAHOE CHEYENNE DENVER DOUGLAS ELBERT EL PASO KIT CARSON LINCOLN LOGAN MORGAN PHILLIPS SEDGWICK TELLER WASHINGTON WELD YUMA KSC023-039-065-137-153-179-181-193-102140- KS . KANSAS COUNTIES INCLUDED ARE CHEYENNE DECATUR GRAHAM NORTON RAWLINS SHERIDAN SHERMAN THOMAS NEC029-057-063-085-087-135-145-102140- Read more

WW 207 TORNADO CO KS NE 101955Z - 110300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 207 NWS Storm Prediction Center Norman OK 255 PM CDT Wed May 10 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Northeast and East-Central Colorado Northwest Kansas Southwest Nebraska * Effective this Wednesday afternoon and evening from 255 PM until 1000 PM CDT. * Primary threats include... A few tornadoes possible Scattered large hail likely with isolated very large hail events to 3 inches in diameter possible Scattered damaging winds and isolated significant gusts to 75 mph possible SUMMARY...Severe storms are expected to develop and increase this afternoon, initially near the Colorado Front Range as well as northwest Kansas along/north of a front. This will include supercells capable of large hail and a few tornadoes, along with the potential for damaging winds with storms on the High Plains of eastern Colorado/northwest Kansas/southwest Nebraska. The tornado watch area is approximately along and 70 statute miles north and south of a line from 10 miles south southwest of Denver CO to 40 miles east southeast of Mccook NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 22020. ...Guyer Read more

WW 0208 Status Updates
STATUS REPORT ON WW 208 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..DEAN..05/10/23 ATTN...WFO...PUB...GLD...DDC...ABQ...AMA... STATUS REPORT FOR WS 208 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC009-011-025-055-061-071-089-099-101-102140- CO . COLORADO COUNTIES INCLUDED ARE BACA BENT CROWLEY HUERFANO KIOWA LAS ANIMAS OTERO PROWERS PUEBLO KSC063-071-075-109-187-199-203-102140- KS . KANSAS COUNTIES INCLUDED ARE GOVE GREELEY HAMILTON LOGAN STANTON WALLACE WICHITA NMC007-021-037-059-102140- NM . NEW MEXICO COUNTIES INCLUDED ARE COLFAX HARDING QUAY Read more

WW 208 SEVERE TSTM CO KS NM OK TX 102020Z - 110400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 208 NWS Storm Prediction Center Norman OK 320 PM CDT Wed May 10 2023 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Colorado Western Kansas Northeast New Mexico Western Oklahoma Panhandle Western Texas Panhandle * Effective this Wednesday afternoon and evening from 320 PM until 1100 PM CDT. * Primary threats include... Scattered damaging winds and isolated significant gusts to 75 mph possible Scattered large hail and isolated very large hail events to 2.5 inches in diameter possible A tornado or two possible SUMMARY...High-based storms including a few supercells will continue to develop near/east of the Front Range and Raton Mesa vicinity, as well as in a somewhat separate corridor into western Kansas. Severe-caliber wind gusts and large hail and the primary hazards. The severe thunderstorm watch area is approximately along and 75 statute miles east and west of a line from 10 miles south southeast of Tucumcari NM to 50 miles north of Lamar CO. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 207... AVIATION...A few severe thunderstorms with hail surface and aloft to 2.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 22025. ...Guyer Read more

Citrus County has been in a burn ban since April 11. The Keetch-Byram Drought Index averaged over 600 for the county. “We have not had a significant amount of rain and that is why we’re in the condition that we’re in,” stated the county emergency management director. “Other areas of the state have received more rainfall.” Chronicle Online (Crystal River, Fla.), May 10, 2023

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0252 PM CDT Wed May 10 2023 Valid 102000Z - 111200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS NORTHEAST COLORADO INTO FAR SOUTHWEST NEBRASKA AND FAR NORTHWEST KANSAS... ...SUMMARY... Scattered severe thunderstorms capable of producing tornadoes, large to very large hail, and severe wind gusts remain likely this afternoon and evening along the High Plains. Additionally, more isolated strong to severe thunderstorms are possible tonight across east Texas and western Louisiana. ...Front Range/High Plains... The forecast remains on track based on recent observations and trends in hi-res guidance. 5% tornado probabilities were expanded slightly across northwest KS where a few cumulus clusters have shown notable vertical development within a recovering boundary layer (where easterly surface winds are enhancing low-level helicity). A significant wind area is introduced for portions of southeast CO into adjacent areas of NM, OK, and KS, where dewpoint depressions over 40 F are noted ahead of developing convection within the higher terrain. These trends suggest the environment is favorable for efficient downward momentum transfer within stronger downdrafts that may result in a couple of 75+ mph gusts. For additional near-term trends, see MCD #754. ...North Dakota... The Marginal area has been extended slightly westward across parts of north-central ND to better align with recent surface and satellite observations, which depict shallow cumulus development along a diffuse surface trough. A few recent runs of hi-res guidance suggest a storm or two may develop within this regime, and modified forecast sounding indicate that locations with temperatures/dewpoints in the mid 70s/upper 50s may feature sufficient buoyancy for effective bulk shear values approaching 30 knots. ..Moore/Leitman.. 05/10/2023 .PREV DISCUSSION... /ISSUED 1135 AM CDT Wed May 10 2023/ ...Front Range/High Plains... An east/northeastward-moving upper trough over Arizona and preceding upper jet exit region will influence the High Plains with a meridional flow pattern into this afternoon and tonight. A lee cyclone will persist over eastern Colorado and the Raton Mesa vicinity with a warm front extending east across northwest Kansas to southeast Nebraska, with the southern High Plains dryline mixing east into a portion of west Texas. A plume of 50s F surface dew points will be maintained to the north of the aforementioned central High Plains front amid persistent easterlies in the lowest 1 km. As large-scale ascent preceding the upper trough overspreads the central to southern Rockies and adjacent High Plains, initial convection will develop over the higher terrain by early afternoon. This activity will spread north-northeastward and increase in coverage through early evening. Several supercells are likely along the Front Range from east-central WY to south-central CO with a primary threat of large hail. Potential will exist for a more intense/long-tracked supercell or two developing off the Palmer Divide towards the Denver metro area and South Platte Valley, where rather enlarged/elongated hodographs coupled with the steep mid-level lapse rate environment could support very large hail and tornadoes. A few slow-moving supercells should be sustained near the dryline/front intersection in the CO/KS/NE border area with a similar very large hail and tornado threat. ...Southern High Plains... While isolated severe wind/hail potential is possible during the late afternoon near the Raton Mesa vicinity, the bulk of severe potential is likely to be delayed until late evening/overnight after the dryline retreats west. This will yield increasing moisture timed with a strengthening low-level jet and greater mid-level DCVA ahead of the Arizona/New Mexico shortwave trough. With a more westerly component to mid-level flow, especially with southern extent, potential will exist for a few supercells capable of large hail and severe wind gusts across the Texas South Plains/Permian Basin. ...Southeast Texas/Louisiana... An MCV over east-central Texas should drift towards the ArkLaTex today. Regenerative, slow-moving deep convection is ongoing along the upper Texas Gulf Coast, with recent scattered development underway to the Louisiana coastal plain. A belt of enhanced low-level winds is consistently progged to spread from just off the Texas coast to the Sabine Valley by afternoon. This would yield enlargement to the low-level hodograph in an otherwise weak deep-layer shear regime. However, given the degree of ongoing convection, diurnal destabilization is expected to be muted. Therefore, some diurnal potential for transient low-level circulations is anticipated but its still unclear whether a more favorable brief tornado and isolated damaging wind corridor can develop. It is possible that the primary severe risk, but still on a relatively isolated basis, occurs late tonight as storms potentially redevelop across far eastern Texas into Louisiana. ...Far northern Minnesota/North Dakota... A low-amplitude shortwave impulse will move east atop the northern extent of the upper ridge near the international border through the afternoon/evening. With the northeast plume of steep mid-level lapse rates impinging on the area, MLCAPE of 500-1500 J/kg should be common from central North Dakota into northwest Minnesota. While the bulk of supercell development should be confined to southern Manitoba, multicell clustering may spread/develop across the international border this evening with a threat for isolated damaging wind and severe hail. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0138 PM CDT Wed May 10 2023 Valid 111200Z - 121200Z No changes to the ongoing forecast. ..Wendt.. 05/10/2023 .PREV DISCUSSION... /ISSUED 0152 AM CDT Wed May 10 2023/ ...Synopsis... As the mid-level trough departs to the east, a belt of stronger southwesterly flow will likely linger over portions of NM and the southern High Plains Thursday. Behind a surface low and ahead of a cold front sweeping east from the Southwest, downslope winds and dry surface conditions may support elevated to near-critical fire-weather conditions Thursday. ...Eastern New Mexico onto the southern High Plains... As the main trough shifts eastward, strong flow over the Rockies will deepen a lee low over the TX Panhandle. Trailing the low, a dryline will keep westerly surface winds breezy over much of eastern NM. Winds should be less potent than days previous as flow weakens, but RH will likely remain nearly as low, 10-15%, during the afternoon. With area fuels remaining dry, elevated fire-weather conditions appear likely Thursday afternoon. There remains considerable uncertainty on the eastern extent and coverage of any critical fire-weather conditions able to develop. The stronger surface winds will gradually weaken from the west as the trough departs. The best overlap with lower RH and dry fuels will remain to the west of the strongest winds through the day. However, some model solutions do suggest potential for a few hours of near-critical conditions across eastern NM, though uncertainty is high. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1229 PM CDT Wed May 10 2023 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS CENTRAL OKLAHOMA INTO NORTHWEST KANSAS... ...SUMMARY... Strong/severe thunderstorms are forecast Thursday across the central and southern Plains, where large hail and a few tornadoes can be expected along with locally damaging winds. Isolated hail/damaging winds are also possible across the lower Mississippi Valley into the Southeastern states. ...Synopsis... A progressive upper-level low is noted translating eastward across the lower CO River Valley in mid-morning water-vapor imagery. Recent guidance has generally captured the progression and amplitude of this wave well over the past 12 hours or so, lending reasonably high confidence in its general evolution over the next 48 hours. This feature is expected to become slightly negatively tilted as it ejects into the southern/central High Plains during the 18-21 UTC period Thursday. The rapid deepening of a lee cyclone over the northern TX Panhandle into western KS will coincide with the eastward mixing of a dryline, which should be draped from southwest KS into western OK and northwest TX by mid-afternoon. The severe weather threat will be concentrated along and east/northeast of this boundary as thunderstorms develop by mid to late afternoon. Along the Gulf Coast, a weak mid-level perturbation, currently over central TX, will migrate east through the day, reaching the lower MS River Valley by peak heating. Thunderstorms developing in the vicinity of this feature will pose a risk for sporadic large hail and damaging winds. ...Central to Southern Plains... Recent surface observations across the southern/central Plains show a plume of rich (mid to upper 60s) dewpoints across much of TX into south-central KS. Poleward moisture advection will increase through Thursday afternoon as the surface low deepens over western KS and the Panhandles region, with widespread mid/upper 60s ahead of the sharpening dryline. Despite the high-quality moisture, mean meridional flow ahead of the low will relegate the steepest mid-level lapse rates (sampled by 12 UTC RAOBs over the High Plains) to western KS. This, in addition to early-morning clouds/showers, will mute the influence of low-level moisture to some degree, but MLCAPE values between 1000-2000 J/kg should be common across the warm sector by midday. 50 knot mid-level flow largely orthogonal to the dryline should overspread KS/OK through the day, resulting in favorable deep-layer shear orientations for discrete convection. Stronger synoptic and mesoscale lift across west/southwest KS will likely result in an arching band of convection, becoming more broken with southeast extent. A second round of storms is possible during the late afternoon/evening hours as a pocket of cold temperatures aloft associated with the upper low traverses western KS. Further south into OK, a combination of more peripheral synoptic lift and slightly stronger capping will limit convective coverage. T-storm development might be locally maximized across southwest to central OK where guidance has been consistently showing a secondary surface low/dryline bulge in latest guidance that may augment forcing for ascent along the dryline. Thunderstorm potential becomes even more conditional with southward extent along the dryline south of the Red River amid stronger capping and weaker ascent. Regardless of coverage, thunderstorms developing across southern KS into OK (and possibly northern TX) will likely take on supercellular characteristics given adequate buoyancy, deep-layer shear, strong effective-layer helicity, and favorable dryline/deep-layer shear vector orientations. All hazards will be possible with these storms, including the potential for very large (2 inch or larger) hail and a significant tornado. ...Lower MS Valley into the Southeast... Scattered thunderstorms will likely be ongoing at the start of the period across the lower MS valley in the vicinity of the mid-level perturbation. This activity will likely intensify through the day amid strong diurnal warming ahead of ongoing convection. Additional thunderstorms are expected along the western FL coast along a diurnally-driven sea breeze, as well as across parts of southwest GA. While buoyancy will be somewhat strong (around 2000-2500 J/kg MLCAPE), modest wind shear suggests intense convection may be somewhat short-lived. Consequently, sporadic large hail and damaging winds will be possible with strong updraft pulses through the day, and perhaps along any organized outflows associated with convective clusters. ..Moore/Leitman.. 05/10/2023 Read more