SPC May 22, 2019 1300 UTC Day 1 Convective Outlook

1 hour 54 minutes ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed May 22 2019 Valid 221300Z - 231200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM WESTERN MISSOURI TO SOUTHEASTERN KANSAS AND NORTHEASTERN OKLAHOMA... ...SUMMARY... The greatest potential for severe thunderstorms is this afternoon into evening, from western Missouri to southeastern Kansas and northeastern Oklahoma. Tornadoes, large/damaging hail and severe gusts all are possible. ...Synopsis... The period begins with a large area of mid/upper-level cyclonic flow covering most of the central/western CONUS, anchored by embedded lows initially evident in moisture-channel imagery over the north- central Plains and the Great Basin. The eastern of the two lows is occluded in low levels and nearly stacked, and is forecast to weaken while ejecting northeastward toward Lake Superior through 12Z. Meanwhile the western low should pivot slowly around the southern/ eastern Great Basin, while assuming less-positive tilt. In between, shortwave ridging and height rises will build over the southern/central Plains. At the surface, 11Z analysis showed the surface manifestation of the eastern mid/upper cyclone, with a low over southeastern SD and occluded front southeastward to the EVV area. A wavy warm front was drawn from there across southern KY and eastern TN, to southern NC and northern SC. This warm front will move northward across the Ohio Valley to the lower Great Lakes through the period. A stationary front extended from the triple point southwestward over the Mid-South, becoming a warm front across north-central to central TX. This boundary will become diffuse and spread northward over OK and AR. A secondary cold front extended from the low across eastern KS and central/western OK. This boundary should stall then retreat northward over OK today, ultimately merging with the remains of the front to its south. The combined front should become better-defined this afternoon and evening across southeastern KS and northern OK. A forecast veering wind shift behind the front -- related to the departure of the deep-tropospheric low -- will make it more convergent this afternoon, while warm-sector theta-e advection contributes to strengthening the associated baroclinic gradient. ...Southern Plains... Scattered to numerous thunderstorms are expected to develop gradually from mid afternoon through this evening along the strengthening frontal zone over the southeastern KS/southwestern MO and northeastern OK region. A more-isolated/conditional threat is evident farther west and late afternoon into evening along the front over north-central OK, and southward into the warm sector this afternoon in central/eastern OK. Any sustained, relatively discrete convection could become supercellular and offer the risk of tornadoes, large to very large hail, and severe gusts. Isolated strong-severe convection may also develop late overnight near the dryline as it retreats across the south-central High Plains. Even with background height rises and lack of substantial mid/upper forcing, intensifying thermodynamic support from below will contribute to a favorable warm-sector parameter space this afternoon. As the boundary layer recovers northward through OK and around the western Ozarks vicinity, the air mass will destabilize from a combination of moist/warm advection and diabatic surface heating. Given the reservoir of available moisture upstream, the return-flow regime should become characterized by surface dew points upper 60s to low 70s F, mean mixing ratios strengthening to the 16-18 g/kg range, and PW 1.5-2 inches. This process will reduce MLCINH to negligible levels by early/mid afternoon, in a northward- shifting way, with MLCAPE reaching the 2500-4000 J/kg range. The LLJ will help to maintain large hodographs with effective SRH above 200 J/kg, amidst 50-60-kt effective-shear magnitude. The more-certain area for convection, and ultimately greatest cumulative concentration, should be with the corridor of low-level frontogenetic forcing and convergence, where severe probabilities remain greatest. Farther south across the warm sector, CAM progs of gradual convective/supercell genesis are uncertain but possible. Based on character and motion of shallower/pre-supercellular elements in high-res guidance, any such development appears related to initial elevated convection in the warm-advection regime becoming surface-based, as the boundary layer moistens, deepens and destabilizes beneath, 0-3-km lapse rates steepen, and CINH erodes. However, increasing boundary-layer theta-e may be offset somewhat, as other progs (e.g., NAM, RAP) also show warming near 700 mb related to poleward advection of northern portions of a residual Mexican EML. Special afternoon sounding releases from SGF/OUN are planned to sample this airmass evolution diagnostically, given that the absence of substantial boundaries south of the front indicates crucial processes could occur mainly above the surface. ...Mid Mississippi Valley to WI... Additional strong-severe convection should develop near the front northeastward across the mid Mississippi Valley, and perhaps as far as southeastern WI/northern IL. This threat will peak late afternoon into early evening, as the warm sector destabilizes and moistens, also with vertical shear supporting supercell and organized multicell potential. A nearly separate regime of destabilization, related less to low-level theta-e advection and more to cooling aloft ahead of the ejecting/occluded low, conditionally may support isolated/brief/marginal severe farther north across parts of eastern/northern WI this afternoon. ...OH and vicinity... Isolated to widely scattered thunderstorms are possible near the warm front and southward into the warm sector this afternoon, near a diurnally destabilizing theta-e axis. The strongest cells may produce marginally severe hail and gusts. Low-level hodographs and deep shear will be favorable for organized multicells or even isolated supercells, especially near the warm front where near- surface flow is most backed. However, the lack of substantial lapse rates aloft and of deep-layer forcing casts convective maintenance/coverage into doubt. ..Edwards/Leitman.. 05/22/2019 Read more

SPC May 22, 2019 1300 UTC Day 1 Convective Outlook

1 hour 54 minutes ago
SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0752 AM CDT Wed May 22 2019 Valid 221300Z - 231200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS FROM WESTERN MISSOURI TO SOUTHEASTERN KANSAS AND NORTHEASTERN OKLAHOMA... ...SUMMARY... The greatest potential for severe thunderstorms is this afternoon into evening, from western Missouri to southeastern Kansas and northeastern Oklahoma. Tornadoes, large/damaging hail and severe gusts all are possible. ...Synopsis... The period begins with a large area of mid/upper-level cyclonic flow covering most of the central/western CONUS, anchored by embedded lows initially evident in moisture-channel imagery over the north- central Plains and the Great Basin. The eastern of the two lows is occluded in low levels and nearly stacked, and is forecast to weaken while ejecting northeastward toward Lake Superior through 12Z. Meanwhile the western low should pivot slowly around the southern/ eastern Great Basin, while assuming less-positive tilt. In between, shortwave ridging and height rises will build over the southern/central Plains. At the surface, 11Z analysis showed the surface manifestation of the eastern mid/upper cyclone, with a low over southeastern SD and occluded front southeastward to the EVV area. A wavy warm front was drawn from there across southern KY and eastern TN, to southern NC and northern SC. This warm front will move northward across the Ohio Valley to the lower Great Lakes through the period. A stationary front extended from the triple point southwestward over the Mid-South, becoming a warm front across north-central to central TX. This boundary will become diffuse and spread northward over OK and AR. A secondary cold front extended from the low across eastern KS and central/western OK. This boundary should stall then retreat northward over OK today, ultimately merging with the remains of the front to its south. The combined front should become better-defined this afternoon and evening across southeastern KS and northern OK. A forecast veering wind shift behind the front -- related to the departure of the deep-tropospheric low -- will make it more convergent this afternoon, while warm-sector theta-e advection contributes to strengthening the associated baroclinic gradient. ...Southern Plains... Scattered to numerous thunderstorms are expected to develop gradually from mid afternoon through this evening along the strengthening frontal zone over the southeastern KS/southwestern MO and northeastern OK region. A more-isolated/conditional threat is evident farther west and late afternoon into evening along the front over north-central OK, and southward into the warm sector this afternoon in central/eastern OK. Any sustained, relatively discrete convection could become supercellular and offer the risk of tornadoes, large to very large hail, and severe gusts. Isolated strong-severe convection may also develop late overnight near the dryline as it retreats across the south-central High Plains. Even with background height rises and lack of substantial mid/upper forcing, intensifying thermodynamic support from below will contribute to a favorable warm-sector parameter space this afternoon. As the boundary layer recovers northward through OK and around the western Ozarks vicinity, the air mass will destabilize from a combination of moist/warm advection and diabatic surface heating. Given the reservoir of available moisture upstream, the return-flow regime should become characterized by surface dew points upper 60s to low 70s F, mean mixing ratios strengthening to the 16-18 g/kg range, and PW 1.5-2 inches. This process will reduce MLCINH to negligible levels by early/mid afternoon, in a northward- shifting way, with MLCAPE reaching the 2500-4000 J/kg range. The LLJ will help to maintain large hodographs with effective SRH above 200 J/kg, amidst 50-60-kt effective-shear magnitude. The more-certain area for convection, and ultimately greatest cumulative concentration, should be with the corridor of low-level frontogenetic forcing and convergence, where severe probabilities remain greatest. Farther south across the warm sector, CAM progs of gradual convective/supercell genesis are uncertain but possible. Based on character and motion of shallower/pre-supercellular elements in high-res guidance, any such development appears related to initial elevated convection in the warm-advection regime becoming surface-based, as the boundary layer moistens, deepens and destabilizes beneath, 0-3-km lapse rates steepen, and CINH erodes. However, increasing boundary-layer theta-e may be offset somewhat, as other progs (e.g., NAM, RAP) also show warming near 700 mb related to poleward advection of northern portions of a residual Mexican EML. Special afternoon sounding releases from SGF/OUN are planned to sample this airmass evolution diagnostically, given that the absence of substantial boundaries south of the front indicates crucial processes could occur mainly above the surface. ...Mid Mississippi Valley to WI... Additional strong-severe convection should develop near the front northeastward across the mid Mississippi Valley, and perhaps as far as southeastern WI/northern IL. This threat will peak late afternoon into early evening, as the warm sector destabilizes and moistens, also with vertical shear supporting supercell and organized multicell potential. A nearly separate regime of destabilization, related less to low-level theta-e advection and more to cooling aloft ahead of the ejecting/occluded low, conditionally may support isolated/brief/marginal severe farther north across parts of eastern/northern WI this afternoon. ...OH and vicinity... Isolated to widely scattered thunderstorms are possible near the warm front and southward into the warm sector this afternoon, near a diurnally destabilizing theta-e axis. The strongest cells may produce marginally severe hail and gusts. Low-level hodographs and deep shear will be favorable for organized multicells or even isolated supercells, especially near the warm front where near- surface flow is most backed. However, the lack of substantial lapse rates aloft and of deep-layer forcing casts convective maintenance/coverage into doubt. ..Edwards/Leitman.. 05/22/2019 Read more

SPC May 22, 2019 Day 4-8 Severe Weather Outlook

5 hours 34 minutes ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0417 AM CDT Wed May 22 2019 Valid 251200Z - 301200Z ...DISCUSSION... Models remain in reasonable agreement with regard to evolution of the synoptic pattern through day 5, but considerable differences arise by day 6 and beyond especially regarding evolution of western U.S. cutoff upper low. Day 4 (Saturday) Shortwave trough will crest upper ridge and move through the Great Lakes during the day before turning southeast into the Northeast States Saturday night. Surface low accompanying this feature will move through eastern Canada while trailing cold front advances southeast through the Great Lakes and Northeast States. Western extension of front should stall across the Central Plains. A dryline will reside near the TX/NM border. Low 60s F dewpoints will advect through the OH Valley warm sector Saturday contributing to modest instability. Thunderstorms may develop along and ahead of the cold front located across the southern Great Lakes and spread southeast into the OH Valley and a portion of the Northeast States. Strong unidirectional wind profiles attending the northern-stream trough will be sufficient for a few organized severe storms. Other strong to severe storms will be possible along portion of the front over the Central Plains where strong instability will reside. Development along West Texas dryline remains uncertain at this time given apparent weak convergence and presence of low-amplitude ridge. Day 5 (Sunday) Some severe storm potential will persist in vicinity of east-west front from the Plains to the OH Valley as well as along southern Plains dryline. But location of best severe storm potential will be dependent on previous day's storms and outflow. By day 7 (Tuesday) both GFS and ECMWF as well as some SREF members indicate an upper speed max will rotate through the base of the western U.S. upper trough and into the southern and central Plains. This would suggest increasing severe potential over the Plains by that time, and severe probabilities will need to be introduced in later updates if models become more consistent. Read more

SPC May 22, 2019 Day 4-8 Severe Weather Outlook

5 hours 34 minutes ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0417 AM CDT Wed May 22 2019 Valid 251200Z - 301200Z ...DISCUSSION... Models remain in reasonable agreement with regard to evolution of the synoptic pattern through day 5, but considerable differences arise by day 6 and beyond especially regarding evolution of western U.S. cutoff upper low. Day 4 (Saturday) Shortwave trough will crest upper ridge and move through the Great Lakes during the day before turning southeast into the Northeast States Saturday night. Surface low accompanying this feature will move through eastern Canada while trailing cold front advances southeast through the Great Lakes and Northeast States. Western extension of front should stall across the Central Plains. A dryline will reside near the TX/NM border. Low 60s F dewpoints will advect through the OH Valley warm sector Saturday contributing to modest instability. Thunderstorms may develop along and ahead of the cold front located across the southern Great Lakes and spread southeast into the OH Valley and a portion of the Northeast States. Strong unidirectional wind profiles attending the northern-stream trough will be sufficient for a few organized severe storms. Other strong to severe storms will be possible along portion of the front over the Central Plains where strong instability will reside. Development along West Texas dryline remains uncertain at this time given apparent weak convergence and presence of low-amplitude ridge. Day 5 (Sunday) Some severe storm potential will persist in vicinity of east-west front from the Plains to the OH Valley as well as along southern Plains dryline. But location of best severe storm potential will be dependent on previous day's storms and outflow. By day 7 (Tuesday) both GFS and ECMWF as well as some SREF members indicate an upper speed max will rotate through the base of the western U.S. upper trough and into the southern and central Plains. This would suggest increasing severe potential over the Plains by that time, and severe probabilities will need to be introduced in later updates if models become more consistent. Read more

SPC May 22, 2019 Day 4-8 Severe Weather Outlook

5 hours 34 minutes ago
Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0417 AM CDT Wed May 22 2019 Valid 251200Z - 301200Z ...DISCUSSION... Models remain in reasonable agreement with regard to evolution of the synoptic pattern through day 5, but considerable differences arise by day 6 and beyond especially regarding evolution of western U.S. cutoff upper low. Day 4 (Saturday) Shortwave trough will crest upper ridge and move through the Great Lakes during the day before turning southeast into the Northeast States Saturday night. Surface low accompanying this feature will move through eastern Canada while trailing cold front advances southeast through the Great Lakes and Northeast States. Western extension of front should stall across the Central Plains. A dryline will reside near the TX/NM border. Low 60s F dewpoints will advect through the OH Valley warm sector Saturday contributing to modest instability. Thunderstorms may develop along and ahead of the cold front located across the southern Great Lakes and spread southeast into the OH Valley and a portion of the Northeast States. Strong unidirectional wind profiles attending the northern-stream trough will be sufficient for a few organized severe storms. Other strong to severe storms will be possible along portion of the front over the Central Plains where strong instability will reside. Development along West Texas dryline remains uncertain at this time given apparent weak convergence and presence of low-amplitude ridge. Day 5 (Sunday) Some severe storm potential will persist in vicinity of east-west front from the Plains to the OH Valley as well as along southern Plains dryline. But location of best severe storm potential will be dependent on previous day's storms and outflow. By day 7 (Tuesday) both GFS and ECMWF as well as some SREF members indicate an upper speed max will rotate through the base of the western U.S. upper trough and into the southern and central Plains. This would suggest increasing severe potential over the Plains by that time, and severe probabilities will need to be introduced in later updates if models become more consistent. Read more

SPC May 22, 2019 0730 UTC Day 3 Severe Thunderstorm Outlook

7 hours 10 minutes ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0242 AM CDT Wed May 22 2019 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM A PORTION OF THE CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY REGION... ...SUMMARY... A few strong to severe storms will be possible on Friday from a portion of the upper Mississippi Valley region into a part of the central and southern Plains. ...Synopsis... Model consensus is that a shortwave trough initially over the central/northern Plains early Friday will continue northeast into the upper MS Valley region during the day. Attendant surface low initially over SD will reach MN by mid-late afternoon with trailing cold front extending southwest through IA and central KS. A warm front will advance northeast through the upper MS Valley and by early evening should extend from the surface low in MN through the southern Great Lakes and into the Ohio Valley. Dryline will reside across west TX during the day, but should retreat into eastern NM during the evening. ...Eastern Kansas through the upper Mississippi Valley region... Richer low-level moisture with mid-upper 60s F dewpoints will advect northeast through the mid-upper MS Valley warm sector during the day and this should contribute to a corridor of moderate instability (1500-2000 J/kg MLCAPE) as the boundary layer warms. Some storms may be ongoing on cool side of the warm front as well as farther west across KS in vicinity of the cold front. Additional storms will probably develop along the cold front or residual outflow boundaries during the afternoon. Flow in the lowest 3 km is forecast to weaken and the strongest mid-upper winds will likely remain north of the warm sector which could be limiting factors for a more robust severe threat. However, winds aloft will support 40-45 kt largely unidirectional effective bulk shear. It appears the parameter space will be sufficient for a threat of some strong to severe storms with large hail and damaging wind the main threats through early evening. ...Southern High Plains area... Storms may be ongoing from a portion of west TX into OK which complicates the forecast to some degree. Nevertheless, initial activity may weaken, with potential for boundary-layer recovery during the afternoon, potentially supporting strong instability with 2000-3000 J/kg MLCAPE. A belt of 40-50 kt mid-level winds will persist over this region, therefore the parameter space will be conditionally supportive of severe storms. While dryline convergence is not expected to be particularly strong and forcing aloft will be weak, potential still exists for isolated storm development either along the dryline or in association with residual boundaries from early convection. Will introduce a marginal risk category this update, but an upgrade to higher probabilities may be needed in future outlooks once some of the mesoscale uncertainties have been mitigated. ..Dial.. 05/22/2019 Read more

SPC May 22, 2019 0730 UTC Day 3 Severe Thunderstorm Outlook

7 hours 10 minutes ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0242 AM CDT Wed May 22 2019 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM A PORTION OF THE CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY REGION... ...SUMMARY... A few strong to severe storms will be possible on Friday from a portion of the upper Mississippi Valley region into a part of the central and southern Plains. ...Synopsis... Model consensus is that a shortwave trough initially over the central/northern Plains early Friday will continue northeast into the upper MS Valley region during the day. Attendant surface low initially over SD will reach MN by mid-late afternoon with trailing cold front extending southwest through IA and central KS. A warm front will advance northeast through the upper MS Valley and by early evening should extend from the surface low in MN through the southern Great Lakes and into the Ohio Valley. Dryline will reside across west TX during the day, but should retreat into eastern NM during the evening. ...Eastern Kansas through the upper Mississippi Valley region... Richer low-level moisture with mid-upper 60s F dewpoints will advect northeast through the mid-upper MS Valley warm sector during the day and this should contribute to a corridor of moderate instability (1500-2000 J/kg MLCAPE) as the boundary layer warms. Some storms may be ongoing on cool side of the warm front as well as farther west across KS in vicinity of the cold front. Additional storms will probably develop along the cold front or residual outflow boundaries during the afternoon. Flow in the lowest 3 km is forecast to weaken and the strongest mid-upper winds will likely remain north of the warm sector which could be limiting factors for a more robust severe threat. However, winds aloft will support 40-45 kt largely unidirectional effective bulk shear. It appears the parameter space will be sufficient for a threat of some strong to severe storms with large hail and damaging wind the main threats through early evening. ...Southern High Plains area... Storms may be ongoing from a portion of west TX into OK which complicates the forecast to some degree. Nevertheless, initial activity may weaken, with potential for boundary-layer recovery during the afternoon, potentially supporting strong instability with 2000-3000 J/kg MLCAPE. A belt of 40-50 kt mid-level winds will persist over this region, therefore the parameter space will be conditionally supportive of severe storms. While dryline convergence is not expected to be particularly strong and forcing aloft will be weak, potential still exists for isolated storm development either along the dryline or in association with residual boundaries from early convection. Will introduce a marginal risk category this update, but an upgrade to higher probabilities may be needed in future outlooks once some of the mesoscale uncertainties have been mitigated. ..Dial.. 05/22/2019 Read more

SPC May 22, 2019 0730 UTC Day 3 Severe Thunderstorm Outlook

7 hours 10 minutes ago
SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0242 AM CDT Wed May 22 2019 Valid 241200Z - 251200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM A PORTION OF THE CENTRAL PLAINS INTO THE UPPER MISSISSIPPI VALLEY REGION... ...SUMMARY... A few strong to severe storms will be possible on Friday from a portion of the upper Mississippi Valley region into a part of the central and southern Plains. ...Synopsis... Model consensus is that a shortwave trough initially over the central/northern Plains early Friday will continue northeast into the upper MS Valley region during the day. Attendant surface low initially over SD will reach MN by mid-late afternoon with trailing cold front extending southwest through IA and central KS. A warm front will advance northeast through the upper MS Valley and by early evening should extend from the surface low in MN through the southern Great Lakes and into the Ohio Valley. Dryline will reside across west TX during the day, but should retreat into eastern NM during the evening. ...Eastern Kansas through the upper Mississippi Valley region... Richer low-level moisture with mid-upper 60s F dewpoints will advect northeast through the mid-upper MS Valley warm sector during the day and this should contribute to a corridor of moderate instability (1500-2000 J/kg MLCAPE) as the boundary layer warms. Some storms may be ongoing on cool side of the warm front as well as farther west across KS in vicinity of the cold front. Additional storms will probably develop along the cold front or residual outflow boundaries during the afternoon. Flow in the lowest 3 km is forecast to weaken and the strongest mid-upper winds will likely remain north of the warm sector which could be limiting factors for a more robust severe threat. However, winds aloft will support 40-45 kt largely unidirectional effective bulk shear. It appears the parameter space will be sufficient for a threat of some strong to severe storms with large hail and damaging wind the main threats through early evening. ...Southern High Plains area... Storms may be ongoing from a portion of west TX into OK which complicates the forecast to some degree. Nevertheless, initial activity may weaken, with potential for boundary-layer recovery during the afternoon, potentially supporting strong instability with 2000-3000 J/kg MLCAPE. A belt of 40-50 kt mid-level winds will persist over this region, therefore the parameter space will be conditionally supportive of severe storms. While dryline convergence is not expected to be particularly strong and forcing aloft will be weak, potential still exists for isolated storm development either along the dryline or in association with residual boundaries from early convection. Will introduce a marginal risk category this update, but an upgrade to higher probabilities may be needed in future outlooks once some of the mesoscale uncertainties have been mitigated. ..Dial.. 05/22/2019 Read more

SPC Day 2 Fire Weather Outlook

7 hours 52 minutes ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...Synopsis... The entrance region of a mid-level jet will linger across portions of New Mexico on D2/Thursday as an upper closed low moves into the northern Rockies. At the surface another lee trough will develop in the southern High Plains. Dry southwesterly flow across New Mexico will lead to afternoon RH values of 5-20%. While surface winds of 20-30 mph will be possible in northern New Mexico, the departing mid-level jet core into the central Plains will mean lighter winds of 15-20 mph in much of southern New Mexico. Due to the reduced surface winds over the most receptive fuels, only elevated fire weather concerns can be expected across the highlighted area. Should pockets of more receptive fuels exist, locally critical fire weather will be possible in those locations. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

7 hours 52 minutes ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...Synopsis... The entrance region of a mid-level jet will linger across portions of New Mexico on D2/Thursday as an upper closed low moves into the northern Rockies. At the surface another lee trough will develop in the southern High Plains. Dry southwesterly flow across New Mexico will lead to afternoon RH values of 5-20%. While surface winds of 20-30 mph will be possible in northern New Mexico, the departing mid-level jet core into the central Plains will mean lighter winds of 15-20 mph in much of southern New Mexico. Due to the reduced surface winds over the most receptive fuels, only elevated fire weather concerns can be expected across the highlighted area. Should pockets of more receptive fuels exist, locally critical fire weather will be possible in those locations. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

7 hours 52 minutes ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...Synopsis... The entrance region of a mid-level jet will linger across portions of New Mexico on D2/Thursday as an upper closed low moves into the northern Rockies. At the surface another lee trough will develop in the southern High Plains. Dry southwesterly flow across New Mexico will lead to afternoon RH values of 5-20%. While surface winds of 20-30 mph will be possible in northern New Mexico, the departing mid-level jet core into the central Plains will mean lighter winds of 15-20 mph in much of southern New Mexico. Due to the reduced surface winds over the most receptive fuels, only elevated fire weather concerns can be expected across the highlighted area. Should pockets of more receptive fuels exist, locally critical fire weather will be possible in those locations. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook

7 hours 52 minutes ago
SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0200 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...Synopsis... The entrance region of a mid-level jet will linger across portions of New Mexico on D2/Thursday as an upper closed low moves into the northern Rockies. At the surface another lee trough will develop in the southern High Plains. Dry southwesterly flow across New Mexico will lead to afternoon RH values of 5-20%. While surface winds of 20-30 mph will be possible in northern New Mexico, the departing mid-level jet core into the central Plains will mean lighter winds of 15-20 mph in much of southern New Mexico. Due to the reduced surface winds over the most receptive fuels, only elevated fire weather concerns can be expected across the highlighted area. Should pockets of more receptive fuels exist, locally critical fire weather will be possible in those locations. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

8 hours 34 minutes ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Wed May 22 2019 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN NEW MEXICO AND FAR WEST TEXAS... ...Synopsis... An upper-level low will depart into Ontario allowing for the longwave pattern in the West to become more meridional. A mid-level jet will round the base of the Great Basin upper low, bringing enhanced southwesterlies across the Southwest into the southern Plains. A lee trough will develop in response within the southern High Plains. Together, these features will drive dry, downslope flow off of the Sierra Madre Occidental during the afternoon today. Minimum RH values should fall to 5-20% across the highlighted areas. Given the less than favorable fuel states across in many locales, a majority of the region will only see elevated fire weather concerns even with 20-30 mph sustained winds. The exception will be across portions of southern New Mexico and far West Texas. Several successive days of critical fire weather have kept ERCs near to above normal in these locations which increases the potential for fire spread. A critical area will be maintained for these areas. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

8 hours 34 minutes ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Wed May 22 2019 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN NEW MEXICO AND FAR WEST TEXAS... ...Synopsis... An upper-level low will depart into Ontario allowing for the longwave pattern in the West to become more meridional. A mid-level jet will round the base of the Great Basin upper low, bringing enhanced southwesterlies across the Southwest into the southern Plains. A lee trough will develop in response within the southern High Plains. Together, these features will drive dry, downslope flow off of the Sierra Madre Occidental during the afternoon today. Minimum RH values should fall to 5-20% across the highlighted areas. Given the less than favorable fuel states across in many locales, a majority of the region will only see elevated fire weather concerns even with 20-30 mph sustained winds. The exception will be across portions of southern New Mexico and far West Texas. Several successive days of critical fire weather have kept ERCs near to above normal in these locations which increases the potential for fire spread. A critical area will be maintained for these areas. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook

8 hours 34 minutes ago
SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0119 AM CDT Wed May 22 2019 Valid 221200Z - 231200Z ...CRITICAL FIRE WEATHER AREA FOR PORTIONS OF SOUTHERN NEW MEXICO AND FAR WEST TEXAS... ...Synopsis... An upper-level low will depart into Ontario allowing for the longwave pattern in the West to become more meridional. A mid-level jet will round the base of the Great Basin upper low, bringing enhanced southwesterlies across the Southwest into the southern Plains. A lee trough will develop in response within the southern High Plains. Together, these features will drive dry, downslope flow off of the Sierra Madre Occidental during the afternoon today. Minimum RH values should fall to 5-20% across the highlighted areas. Given the less than favorable fuel states across in many locales, a majority of the region will only see elevated fire weather concerns even with 20-30 mph sustained winds. The exception will be across portions of southern New Mexico and far West Texas. Several successive days of critical fire weather have kept ERCs near to above normal in these locations which increases the potential for fire spread. A critical area will be maintained for these areas. ..Wendt.. 05/22/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC May 22, 2019 0600 UTC Day 2 Convective Outlook

8 hours 48 minutes ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHERN AND CENTRAL PLAINS AND NORTHEAST STATES... ...SUMMARY... Severe storms with large hail, damaging wind and tornadoes will be possible over a part of the central and southern Plains Thursday. Other severe storms with a threat for mainly damaging wind and large hail are expected from a portion of the Northeast States into the Ohio Valley. ...Synopsis... A significant shortwave trough will rotate through the base of an upper low centered over the Great Basin 12Z Thursday and into the central High Plains Thursday afternoon and evening. Farther east, a low-amplitude shortwave trough will crest an upper ridge anchored over the southeast U.S. and move through the Great Lakes before turning southeast into the Northeast States Thursday evening. At the surface a warm or stationary front will likely extend from the middle MS Valley region southwest into southern KS. A dryline will reside near the TX/NM border. Warm front is expected to lift slowly north through central and eastern KS, while the dryline mixes through west TX during the day. Farther east a surface low attending the northern-stream shortwave trough will move through southern Canada while trailing cold front advances southeast through the Great Lakes. A warm front will advance east into a portion of the Northeast States. ...Central and southern Plains... Elevated storms may be ongoing over a portion of western and central KS north of the warm front early Thursday and could pose some risk for large hail. A very moist and unstable airmass with dewpoints in the upper 60s to around 70 F will reside in the warm sector from southern KS to OK and TX beneath 7-7.5 C/km mid-level lapse rates, contributing to moderate to strong instability (2500-3500 J/kg MLCAPE). Forcing for ascent attending the northeast-ejecting upper jet will glance western portion of the warm sector and in vicinity of the dryline that should mix east into the TX Panhandle and west TX. Storms development is probable along this boundary from the TX Panhandle into southwest KS where convergence will be maximized. Vertical wind profiles with 45-55 kt effective bulk shear will support supercells, and 0-2km hodographs size will also increase as the low-level jet strengthens during the late afternoon and evening. Activity will spread northeast with all hazards possible with storms remaining in warm sector. Some storms may eventually move or develop north of the warm front, but strong effective bulk shear and moderate MUCAPE will still support potential for supercells with large hail. Overnight the entrance region of the upper jet and merging of Pacific front with dryline should promote additional severe thunderstorm development across west TX. ...Northeast States through Ohio Valley... The warm sector will gradually moisten west of the warm front during the day with low to mid 60s F dewpoints beneath 6.5 C/km lapse rates, along with diabatic warming contributing to modest instability (800-1200 J/kg MLCAPE). Current indications are that storms will most likely develop along and ahead of southeast-advancing cold front spread southeast through the OH Valley and Northeast States during the afternoon and evening. Winds will strengthen as the mid-level speed max attending the shortwave trough approaches the region with effective shear supporting supercells. These storms may produce large hail, damaging wind and a couple of tornadoes as they move southeast through the region later Thursday afternoon into the evening. ...MAXIMUM RISK BY HAZARD... Tornado: 10% SIG - Enhanced Wind: 15% SIG - Slight Hail: 30% SIG - Enhanced ..Dial.. 05/22/2019 Read more

SPC May 22, 2019 0600 UTC Day 2 Convective Outlook

8 hours 48 minutes ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHERN AND CENTRAL PLAINS AND NORTHEAST STATES... ...SUMMARY... Severe storms with large hail, damaging wind and tornadoes will be possible over a part of the central and southern Plains Thursday. Other severe storms with a threat for mainly damaging wind and large hail are expected from a portion of the Northeast States into the Ohio Valley. ...Synopsis... A significant shortwave trough will rotate through the base of an upper low centered over the Great Basin 12Z Thursday and into the central High Plains Thursday afternoon and evening. Farther east, a low-amplitude shortwave trough will crest an upper ridge anchored over the southeast U.S. and move through the Great Lakes before turning southeast into the Northeast States Thursday evening. At the surface a warm or stationary front will likely extend from the middle MS Valley region southwest into southern KS. A dryline will reside near the TX/NM border. Warm front is expected to lift slowly north through central and eastern KS, while the dryline mixes through west TX during the day. Farther east a surface low attending the northern-stream shortwave trough will move through southern Canada while trailing cold front advances southeast through the Great Lakes. A warm front will advance east into a portion of the Northeast States. ...Central and southern Plains... Elevated storms may be ongoing over a portion of western and central KS north of the warm front early Thursday and could pose some risk for large hail. A very moist and unstable airmass with dewpoints in the upper 60s to around 70 F will reside in the warm sector from southern KS to OK and TX beneath 7-7.5 C/km mid-level lapse rates, contributing to moderate to strong instability (2500-3500 J/kg MLCAPE). Forcing for ascent attending the northeast-ejecting upper jet will glance western portion of the warm sector and in vicinity of the dryline that should mix east into the TX Panhandle and west TX. Storms development is probable along this boundary from the TX Panhandle into southwest KS where convergence will be maximized. Vertical wind profiles with 45-55 kt effective bulk shear will support supercells, and 0-2km hodographs size will also increase as the low-level jet strengthens during the late afternoon and evening. Activity will spread northeast with all hazards possible with storms remaining in warm sector. Some storms may eventually move or develop north of the warm front, but strong effective bulk shear and moderate MUCAPE will still support potential for supercells with large hail. Overnight the entrance region of the upper jet and merging of Pacific front with dryline should promote additional severe thunderstorm development across west TX. ...Northeast States through Ohio Valley... The warm sector will gradually moisten west of the warm front during the day with low to mid 60s F dewpoints beneath 6.5 C/km lapse rates, along with diabatic warming contributing to modest instability (800-1200 J/kg MLCAPE). Current indications are that storms will most likely develop along and ahead of southeast-advancing cold front spread southeast through the OH Valley and Northeast States during the afternoon and evening. Winds will strengthen as the mid-level speed max attending the shortwave trough approaches the region with effective shear supporting supercells. These storms may produce large hail, damaging wind and a couple of tornadoes as they move southeast through the region later Thursday afternoon into the evening. ...MAXIMUM RISK BY HAZARD... Tornado: 10% SIG - Enhanced Wind: 15% SIG - Slight Hail: 30% SIG - Enhanced ..Dial.. 05/22/2019 Read more

SPC May 22, 2019 0600 UTC Day 2 Convective Outlook

8 hours 48 minutes ago
SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Wed May 22 2019 Valid 231200Z - 241200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS OVER A PORTION OF THE SOUTHERN AND CENTRAL PLAINS AND NORTHEAST STATES... ...SUMMARY... Severe storms with large hail, damaging wind and tornadoes will be possible over a part of the central and southern Plains Thursday. Other severe storms with a threat for mainly damaging wind and large hail are expected from a portion of the Northeast States into the Ohio Valley. ...Synopsis... A significant shortwave trough will rotate through the base of an upper low centered over the Great Basin 12Z Thursday and into the central High Plains Thursday afternoon and evening. Farther east, a low-amplitude shortwave trough will crest an upper ridge anchored over the southeast U.S. and move through the Great Lakes before turning southeast into the Northeast States Thursday evening. At the surface a warm or stationary front will likely extend from the middle MS Valley region southwest into southern KS. A dryline will reside near the TX/NM border. Warm front is expected to lift slowly north through central and eastern KS, while the dryline mixes through west TX during the day. Farther east a surface low attending the northern-stream shortwave trough will move through southern Canada while trailing cold front advances southeast through the Great Lakes. A warm front will advance east into a portion of the Northeast States. ...Central and southern Plains... Elevated storms may be ongoing over a portion of western and central KS north of the warm front early Thursday and could pose some risk for large hail. A very moist and unstable airmass with dewpoints in the upper 60s to around 70 F will reside in the warm sector from southern KS to OK and TX beneath 7-7.5 C/km mid-level lapse rates, contributing to moderate to strong instability (2500-3500 J/kg MLCAPE). Forcing for ascent attending the northeast-ejecting upper jet will glance western portion of the warm sector and in vicinity of the dryline that should mix east into the TX Panhandle and west TX. Storms development is probable along this boundary from the TX Panhandle into southwest KS where convergence will be maximized. Vertical wind profiles with 45-55 kt effective bulk shear will support supercells, and 0-2km hodographs size will also increase as the low-level jet strengthens during the late afternoon and evening. Activity will spread northeast with all hazards possible with storms remaining in warm sector. Some storms may eventually move or develop north of the warm front, but strong effective bulk shear and moderate MUCAPE will still support potential for supercells with large hail. Overnight the entrance region of the upper jet and merging of Pacific front with dryline should promote additional severe thunderstorm development across west TX. ...Northeast States through Ohio Valley... The warm sector will gradually moisten west of the warm front during the day with low to mid 60s F dewpoints beneath 6.5 C/km lapse rates, along with diabatic warming contributing to modest instability (800-1200 J/kg MLCAPE). Current indications are that storms will most likely develop along and ahead of southeast-advancing cold front spread southeast through the OH Valley and Northeast States during the afternoon and evening. Winds will strengthen as the mid-level speed max attending the shortwave trough approaches the region with effective shear supporting supercells. These storms may produce large hail, damaging wind and a couple of tornadoes as they move southeast through the region later Thursday afternoon into the evening. ...MAXIMUM RISK BY HAZARD... Tornado: 10% SIG - Enhanced Wind: 15% SIG - Slight Hail: 30% SIG - Enhanced ..Dial.. 05/22/2019 Read more
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