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SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1150 AM CDT Sun May 19 2024 Valid 191700Z - 201200Z The previous forecast remains on track, and only minor changes were made with this update. In particular, the Elevated highlights were expanded slightly southward in central AZ, where modestly dry/breezy conditions are expected over recent/ongoing fires. ..Weinman.. 05/19/2024 .PREV DISCUSSION... /ISSUED 0217 AM CDT Sun May 19 2024/ ...Synopsis... Mid-level troughing will amplify across the western CONUS today. Meanwhile, a mid-level speed max will accelerate from the Southwest into the southern Plains. As a result, lee cyclogenesis is anticipated in the central High Plains. This will lead to dry and breezy conditions across much of the central CONUS, but especially across the Southwest and into the southern High Plains. Sustained winds of 15 to 25 mph are expected across eastern New Mexico and perhaps into the TX/OK Panhandles and far southeast Colorado where single digit relative humidity is likely. Fuels across eastern New Mexico and vicinity are only marginally dry after recent rainfall, but will continue to dry during the day. Therefore, with low-end Critical meteorological conditions and marginally dry fuels, an Elevated delineation is warranted. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1120 AM CDT Sun May 19 2024 Valid 191630Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM SOUTH DAKOTA INTO WESTERN NEBRASKA...AND ALONG THE SOUTHEAST COAST OF FLORIDA... ...SUMMARY... Numerous severe thunderstorms capable of widespread damaging winds and giant hail are expected this afternoon and evening across portions of Kansas and northern Oklahoma. Gusts of 75-100 mph are possible, along with very large hail and a few tornadoes. ...KS/OK... Morning water vapor imagery shows a shortwave trough over northern AZ. This feature is expected to accelerate eastward this afternoon, with an associated mid/upper level jet max nosing into the central High Plains. This will lead to scattered high-based thunderstorms over southeast CO by mid-afternoon, capable of locally gusty winds and hail. As this activity builds eastward across the dryline, rapid intensification of supercell storms is expected. Forecast soundings show a relatively deep boundary-layer, but large CAPE values and dry-adiabatic mid-level lapse rates. Deep-layer shear profiles will promote rotating storms capable of very large hail, damaging winds, and a tornado or two across southwest KS and any more isolated cells that form southward along the dryline into western Oklahoma. As this activity moves eastward, congealing outflows will likely result in a fast-moving QLCS capable of widespread significant wind damage for a few hours. It remains unclear how far east this threat will persist, but given current model guidance, will not change the ongoing bounds of the ENH/MDT risk areas in eastern KS. ...Eastern FL... A surface cold front is sagging southward across the central FL peninsula today. Along and ahead of the front, very warm/moist low-level conditions persist with dewpoints in the low-mid 70s and strong daytime heating occurring. It appears likely that at least scattered thunderstorms will form near/along the east-coast sea breeze later this afternoon. Any storm that can intensify before it moves offshore would potentially acquire supercell characteristics and pose a risk of large hail and damaging wind gusts. See mesoscale discussion #829 for further details. ...SD/NE/Northeast CO... Strong heating is occurring across much of western SD/NE, where southerly low-level winds are helping to transport 50s dewpoints in the region. A weak shortwave trough currently over WY will approach the region by mid-afternoon, helping to initiate scattered thunderstorms from the Black Hills region southward into western NE and northeast CO. These storms will be relatively high-based, but in an environment of sufficient vertical shear to promote organized multicell or supercell structures capable of damaging winds and hail. Storms will persist through much of the evening and spread into central SD/NE before weakening. ..Hart/Wendt.. 05/19/2024 Read more

No watches are valid as of Sun May 19 16:25:02 UTC 2024.

No Mesoscale Discussions are in effect as of Sun May 19 13:52:02 UTC 2024.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 AM CDT Sun May 19 2024 Valid 191300Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PORTIONS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF EAST-CENTRAL/SOUTHEASTERN FLORIDA... ...SUMMARY... An organized swath of severe thunderstorm wind (potential derecho) is expected mainly across parts of Kansas this afternoon and evening, possibly extending into northern Oklahoma. Gusts of 75-100 mph are possible, along with large hail and a few tornadoes. ...Synopsis... A broad fetch of westerly to southwesterly flow will cover most of the central CONUS. This will persist downstream from a synoptic- scale trough over the Pacific Northwest that should amplify into the Great Basin region through the period. The downstream flow field contains several embedded shortwaves, including a convectively generated perturbation now over parts of KS/NE. This feature should eject northeastward over the upper Mississippi Valley this evening, and away from the main threat area. However, an upstream shortwave trough -- apparent in moisture-channel imagery over the Four Corners region -- will move east-northeastward and influence convective potential over the central Plains this afternoon and evening. Elsewhere aloft, a persistent trough was evident across portions of VA, the Carolinas, GA, and AL, with cyclonic flow downstream over the southern Atlantic Coast and as far south as most of the FL Peninsula. This trough should reach the NC/SC/GA coastlines and northwestern FL by 00Z, and south FL by 12Z tomorrow. The 11Z surface analysis showed a cold front from northeastern ON across Lower MI, western IL, west-central MO and east-central KS, where it is being overtaken by an outflow boundary arching southwestward across south-central KS to the OK Panhandle. The outflow boundary is expected to stall in the next few hours, then shift northward over southern and central KS through the day. A dryline extended from eastern CO across the western TX Panhandle to near LBB, MAF and northern Coahuila. The dryline should mix eastward slightly today, reaching near the KS/CO line and eastern TX Panhandle by mid/late afternoon. Elsewhere, a weak cold front was drawn from a low offshore from NC southwestward over northern FL, and should move slowly southward into central FL today. ...Central Plains... Thunderstorms are expected to develop during mid/late afternoon behind the dryline over the eastern Raton Mesa region, as well as along the dryline itself, and move east-northeastward to eastward into increasing moisture and instability. As they do, some of the activity should aggregate into clusters as smaller-scale outflows combine and enlarge. With supportive internal feedback of an organizing cold pool, associated forced ascent at the front and rear-inflow jet, and supportive midlevel winds for downward momentum transfer, as well as the residual and diurnally destabilized outflow boundary, the overall meso-alpha-scale pattern appears quite suitable for an organized, potentially significant-severe convective-wind swath to result. The most probable corridor for such growth still appears to be across KS in and near the "moderate risk" corridor, driven by wind probabilities. Initially separate dryline development over the northeastern TX Panhandle and northwestern OK may blend into (or even get undercut by outflow from) the broader event as well, after a few hours' discrete time to its south, with a threat of large hail, locally severe gusts and perhaps a tornado or two. Other afternoon development, along the dryline, in the mountains of northern CO and southeastern WY, and over the Black Hills, may move east- northeastward across a narrow moist sector and produce severe gusts and hail into parts of the adjoining High Plains of western NE and the Dakotas. Near and behind the KS-to-Panhandles dryline segment, the storm- initiation environment will be characterized by increasing large-scale ascent and upper divergence ahead of the ejecting Four Corners shortwave trough, as well as strong diurnal heating, mixing and deepening of the boundary layer. Superposition of these effects will lead to nearly 9 deg C/km lapse rates throughout the lower/ middle troposphere, supporting 2000-3000 J/kg MLCAPE just east of the dryline. A deep subcloud layer conducive to strong-severe downdrafts will be available to storms over western KS from the beginning, and should support growth/merger of resultant outflows before activity moves into greater moisture. Forced ascent of the moist boundary layer should help to sustain the forward-propagating complex into strengthening nocturnal MLCINH at least across eastern KS, and perhaps into parts of the lower Missouri Valley, before it weakens tonight. ...FL... Scattered thunderstorms should develop this afternoon near the I-95 corridor and roughly between MIA and the Space Coast, along and south of a weak cold front. Organized multicells and a few supercells are possible, offering large hail and damaging to locally severe gusts before they move offshore. An active Atlantic sea-breeze pattern will be augmented by mid/upper support preceding the trough aloft. Strong diurnal heating, a deep troposphere and rich low-level moisture (with dewpoints commonly in the 70s F and 16.5-18.5 g/kg mean mixing ratios) will support 2000-3000 J/kg peak MLCAPE. Though weak near-surface winds will limit hodograph size, 30-45 kt effective-shear magnitudes and potential boundary interactions will support storm organization, including supercell potential. ..Edwards/Goss.. 05/19/2024 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 AM CDT Sun May 19 2024 Valid 191300Z - 201200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS IN PORTIONS OF KANSAS... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS OVER PARTS OF EAST-CENTRAL/SOUTHEASTERN FLORIDA... ...SUMMARY... An organized swath of severe thunderstorm wind (potential derecho) is expected mainly across parts of Kansas this afternoon and evening, possibly extending into northern Oklahoma. Gusts of 75-100 mph are possible, along with large hail and a few tornadoes. ...Synopsis... A broad fetch of westerly to southwesterly flow will cover most of the central CONUS. This will persist downstream from a synoptic- scale trough over the Pacific Northwest that should amplify into the Great Basin region through the period. The downstream flow field contains several embedded shortwaves, including a convectively generated perturbation now over parts of KS/NE. This feature should eject northeastward over the upper Mississippi Valley this evening, and away from the main threat area. However, an upstream shortwave trough -- apparent in moisture-channel imagery over the Four Corners region -- will move east-northeastward and influence convective potential over the central Plains this afternoon and evening. Elsewhere aloft, a persistent trough was evident across portions of VA, the Carolinas, GA, and AL, with cyclonic flow downstream over the southern Atlantic Coast and as far south as most of the FL Peninsula. This trough should reach the NC/SC/GA coastlines and northwestern FL by 00Z, and south FL by 12Z tomorrow. The 11Z surface analysis showed a cold front from northeastern ON across Lower MI, western IL, west-central MO and east-central KS, where it is being overtaken by an outflow boundary arching southwestward across south-central KS to the OK Panhandle. The outflow boundary is expected to stall in the next few hours, then shift northward over southern and central KS through the day. A dryline extended from eastern CO across the western TX Panhandle to near LBB, MAF and northern Coahuila. The dryline should mix eastward slightly today, reaching near the KS/CO line and eastern TX Panhandle by mid/late afternoon. Elsewhere, a weak cold front was drawn from a low offshore from NC southwestward over northern FL, and should move slowly southward into central FL today. ...Central Plains... Thunderstorms are expected to develop during mid/late afternoon behind the dryline over the eastern Raton Mesa region, as well as along the dryline itself, and move east-northeastward to eastward into increasing moisture and instability. As they do, some of the activity should aggregate into clusters as smaller-scale outflows combine and enlarge. With supportive internal feedback of an organizing cold pool, associated forced ascent at the front and rear-inflow jet, and supportive midlevel winds for downward momentum transfer, as well as the residual and diurnally destabilized outflow boundary, the overall meso-alpha-scale pattern appears quite suitable for an organized, potentially significant-severe convective-wind swath to result. The most probable corridor for such growth still appears to be across KS in and near the "moderate risk" corridor, driven by wind probabilities. Initially separate dryline development over the northeastern TX Panhandle and northwestern OK may blend into (or even get undercut by outflow from) the broader event as well, after a few hours' discrete time to its south, with a threat of large hail, locally severe gusts and perhaps a tornado or two. Other afternoon development, along the dryline, in the mountains of northern CO and southeastern WY, and over the Black Hills, may move east- northeastward across a narrow moist sector and produce severe gusts and hail into parts of the adjoining High Plains of western NE and the Dakotas. Near and behind the KS-to-Panhandles dryline segment, the storm- initiation environment will be characterized by increasing large-scale ascent and upper divergence ahead of the ejecting Four Corners shortwave trough, as well as strong diurnal heating, mixing and deepening of the boundary layer. Superposition of these effects will lead to nearly 9 deg C/km lapse rates throughout the lower/ middle troposphere, supporting 2000-3000 J/kg MLCAPE just east of the dryline. A deep subcloud layer conducive to strong-severe downdrafts will be available to storms over western KS from the beginning, and should support growth/merger of resultant outflows before activity moves into greater moisture. Forced ascent of the moist boundary layer should help to sustain the forward-propagating complex into strengthening nocturnal MLCINH at least across eastern KS, and perhaps into parts of the lower Missouri Valley, before it weakens tonight. ...FL... Scattered thunderstorms should develop this afternoon near the I-95 corridor and roughly between MIA and the Space Coast, along and south of a weak cold front. Organized multicells and a few supercells are possible, offering large hail and damaging to locally severe gusts before they move offshore. An active Atlantic sea-breeze pattern will be augmented by mid/upper support preceding the trough aloft. Strong diurnal heating, a deep troposphere and rich low-level moisture (with dewpoints commonly in the 70s F and 16.5-18.5 g/kg mean mixing ratios) will support 2000-3000 J/kg peak MLCAPE. Though weak near-surface winds will limit hodograph size, 30-45 kt effective-shear magnitudes and potential boundary interactions will support storm organization, including supercell potential. ..Edwards/Goss.. 05/19/2024 Read more