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SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 AM CDT Sun Jul 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The persistent upper-level pattern featuring a ridge over the west and a trough in the central/eastern U.S. will continue on Monday. Some very minor enhancement to mid/upper west/southwesterly flow is possible across parts of the Mid-Atlantic/central Appalachian vicinity as several minor vorticity maxima migrate through the eastern periphery of the upper trough. However, generally weak deep-layer flow will prevail over the CONUS. A moist summertime airmass will exist east of the Rockies, while pockets of stronger destabilization supports widespread thunderstorm activity. Overall, organized severe potential appears low. ...PA/WV into the Mid-Atlantic/Chesapeake Bay vicinity... Vertically veering, but weak low-level flow beneath 25-40 kt southwesterly flow near/above 500 mb will result in 30-40 kt effective shear magnitudes. Typically this would aid in organized thunderstorm activity. However, lapse rates are forecast to remain very poor over the region. Furthermore, areas of morning convection are depicted across parts of NC/VA with broader areas of cloud cover possible further north. Overall, destabilization is forecast to be weak. If any pockets of stronger heating occur, a few strong storms could produce wet microbursts given PW values nearing 2 inches. However, lackluster thermodynamic profiles suggest thunderstorm activity should largely remain disorganized and sub-severe, precluding severe probabilities at this time. ...Eastern ND/central MN/northwest WI... Isolated thunderstorms are expected to develop ahead of a southward-moving surface boundary Monday afternoon and evening. Surface dewpoints in the mid-60s F will contribute to MLCAPE around 1000-1500 J/kg. Vertical shear is expected to remain very weak over the region, but sufficient instability, along with modestly steep low-level lapse rates may support brief strong thunderstorms. Gusty winds may accompany this activity, or perhaps small hail given somewhat cool temperatures aloft, but overall severe potential appears low. ..Leitman.. 07/21/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 AM CDT Sun Jul 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The persistent upper-level pattern featuring a ridge over the west and a trough in the central/eastern U.S. will continue on Monday. Some very minor enhancement to mid/upper west/southwesterly flow is possible across parts of the Mid-Atlantic/central Appalachian vicinity as several minor vorticity maxima migrate through the eastern periphery of the upper trough. However, generally weak deep-layer flow will prevail over the CONUS. A moist summertime airmass will exist east of the Rockies, while pockets of stronger destabilization supports widespread thunderstorm activity. Overall, organized severe potential appears low. ...PA/WV into the Mid-Atlantic/Chesapeake Bay vicinity... Vertically veering, but weak low-level flow beneath 25-40 kt southwesterly flow near/above 500 mb will result in 30-40 kt effective shear magnitudes. Typically this would aid in organized thunderstorm activity. However, lapse rates are forecast to remain very poor over the region. Furthermore, areas of morning convection are depicted across parts of NC/VA with broader areas of cloud cover possible further north. Overall, destabilization is forecast to be weak. If any pockets of stronger heating occur, a few strong storms could produce wet microbursts given PW values nearing 2 inches. However, lackluster thermodynamic profiles suggest thunderstorm activity should largely remain disorganized and sub-severe, precluding severe probabilities at this time. ...Eastern ND/central MN/northwest WI... Isolated thunderstorms are expected to develop ahead of a southward-moving surface boundary Monday afternoon and evening. Surface dewpoints in the mid-60s F will contribute to MLCAPE around 1000-1500 J/kg. Vertical shear is expected to remain very weak over the region, but sufficient instability, along with modestly steep low-level lapse rates may support brief strong thunderstorms. Gusty winds may accompany this activity, or perhaps small hail given somewhat cool temperatures aloft, but overall severe potential appears low. ..Leitman.. 07/21/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 AM CDT Sun Jul 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The persistent upper-level pattern featuring a ridge over the west and a trough in the central/eastern U.S. will continue on Monday. Some very minor enhancement to mid/upper west/southwesterly flow is possible across parts of the Mid-Atlantic/central Appalachian vicinity as several minor vorticity maxima migrate through the eastern periphery of the upper trough. However, generally weak deep-layer flow will prevail over the CONUS. A moist summertime airmass will exist east of the Rockies, while pockets of stronger destabilization supports widespread thunderstorm activity. Overall, organized severe potential appears low. ...PA/WV into the Mid-Atlantic/Chesapeake Bay vicinity... Vertically veering, but weak low-level flow beneath 25-40 kt southwesterly flow near/above 500 mb will result in 30-40 kt effective shear magnitudes. Typically this would aid in organized thunderstorm activity. However, lapse rates are forecast to remain very poor over the region. Furthermore, areas of morning convection are depicted across parts of NC/VA with broader areas of cloud cover possible further north. Overall, destabilization is forecast to be weak. If any pockets of stronger heating occur, a few strong storms could produce wet microbursts given PW values nearing 2 inches. However, lackluster thermodynamic profiles suggest thunderstorm activity should largely remain disorganized and sub-severe, precluding severe probabilities at this time. ...Eastern ND/central MN/northwest WI... Isolated thunderstorms are expected to develop ahead of a southward-moving surface boundary Monday afternoon and evening. Surface dewpoints in the mid-60s F will contribute to MLCAPE around 1000-1500 J/kg. Vertical shear is expected to remain very weak over the region, but sufficient instability, along with modestly steep low-level lapse rates may support brief strong thunderstorms. Gusty winds may accompany this activity, or perhaps small hail given somewhat cool temperatures aloft, but overall severe potential appears low. ..Leitman.. 07/21/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1227 AM CDT Sun Jul 21 2024 Valid 221200Z - 231200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe-thunderstorm potential appears low on Monday. ...Synopsis... The persistent upper-level pattern featuring a ridge over the west and a trough in the central/eastern U.S. will continue on Monday. Some very minor enhancement to mid/upper west/southwesterly flow is possible across parts of the Mid-Atlantic/central Appalachian vicinity as several minor vorticity maxima migrate through the eastern periphery of the upper trough. However, generally weak deep-layer flow will prevail over the CONUS. A moist summertime airmass will exist east of the Rockies, while pockets of stronger destabilization supports widespread thunderstorm activity. Overall, organized severe potential appears low. ...PA/WV into the Mid-Atlantic/Chesapeake Bay vicinity... Vertically veering, but weak low-level flow beneath 25-40 kt southwesterly flow near/above 500 mb will result in 30-40 kt effective shear magnitudes. Typically this would aid in organized thunderstorm activity. However, lapse rates are forecast to remain very poor over the region. Furthermore, areas of morning convection are depicted across parts of NC/VA with broader areas of cloud cover possible further north. Overall, destabilization is forecast to be weak. If any pockets of stronger heating occur, a few strong storms could produce wet microbursts given PW values nearing 2 inches. However, lackluster thermodynamic profiles suggest thunderstorm activity should largely remain disorganized and sub-severe, precluding severe probabilities at this time. ...Eastern ND/central MN/northwest WI... Isolated thunderstorms are expected to develop ahead of a southward-moving surface boundary Monday afternoon and evening. Surface dewpoints in the mid-60s F will contribute to MLCAPE around 1000-1500 J/kg. Vertical shear is expected to remain very weak over the region, but sufficient instability, along with modestly steep low-level lapse rates may support brief strong thunderstorms. Gusty winds may accompany this activity, or perhaps small hail given somewhat cool temperatures aloft, but overall severe potential appears low. ..Leitman.. 07/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Jul 21 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible this afternoon into early evening across parts of central and southern Arizona, and from southern Colorado to northeast New Mexico. ...Southwest... Scattered to widespread thunderstorms are expected this afternoon through sunset within a generally modest north-northwesterly mid/upper flow regime between an anticyclone over the western Great Basin and a low-amplitude trough in the central states. The most likely corridors for thunderstorm development will be across the southern Rockies and the Mogollon Rim. For the CO/NM portion, more favorable wind profiles will exist here, but buoyancy will largely remain weak owing to below-normal surface temperatures. Convection will probably struggle to greatly intensify, but a few updrafts may acquire transient supercell structure and be capable of marginally severe hail during the afternoon. Storms should largely consolidate into multicell clusters moving south-southeastward, with mainly a strong-gust threat over southeast CO and northeast NM that subsides closer to sunset. For the AZ portion, deep-layer shear will remain weak, but a more northerly orientation to the mid/upper flow should foster convection over the Rim spreading south into the lower deserts. Buoyancy south of the Rim should be moderate, with MLCAPE of 1000-2000 J/kg amid hot temperatures and low to mid 60s surface dew points. Loose multicell clustering may occur as outflows spread south-southwestward. While small to marginally severe hail is possible along the Rim, strong to isolated severe gusts will be the main hazard before convection weakens after sunset. ..Grams/Lyons.. 07/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Jul 21 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible this afternoon into early evening across parts of central and southern Arizona, and from southern Colorado to northeast New Mexico. ...Southwest... Scattered to widespread thunderstorms are expected this afternoon through sunset within a generally modest north-northwesterly mid/upper flow regime between an anticyclone over the western Great Basin and a low-amplitude trough in the central states. The most likely corridors for thunderstorm development will be across the southern Rockies and the Mogollon Rim. For the CO/NM portion, more favorable wind profiles will exist here, but buoyancy will largely remain weak owing to below-normal surface temperatures. Convection will probably struggle to greatly intensify, but a few updrafts may acquire transient supercell structure and be capable of marginally severe hail during the afternoon. Storms should largely consolidate into multicell clusters moving south-southeastward, with mainly a strong-gust threat over southeast CO and northeast NM that subsides closer to sunset. For the AZ portion, deep-layer shear will remain weak, but a more northerly orientation to the mid/upper flow should foster convection over the Rim spreading south into the lower deserts. Buoyancy south of the Rim should be moderate, with MLCAPE of 1000-2000 J/kg amid hot temperatures and low to mid 60s surface dew points. Loose multicell clustering may occur as outflows spread south-southwestward. While small to marginally severe hail is possible along the Rim, strong to isolated severe gusts will be the main hazard before convection weakens after sunset. ..Grams/Lyons.. 07/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Jul 21 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible this afternoon into early evening across parts of central and southern Arizona, and from southern Colorado to northeast New Mexico. ...Southwest... Scattered to widespread thunderstorms are expected this afternoon through sunset within a generally modest north-northwesterly mid/upper flow regime between an anticyclone over the western Great Basin and a low-amplitude trough in the central states. The most likely corridors for thunderstorm development will be across the southern Rockies and the Mogollon Rim. For the CO/NM portion, more favorable wind profiles will exist here, but buoyancy will largely remain weak owing to below-normal surface temperatures. Convection will probably struggle to greatly intensify, but a few updrafts may acquire transient supercell structure and be capable of marginally severe hail during the afternoon. Storms should largely consolidate into multicell clusters moving south-southeastward, with mainly a strong-gust threat over southeast CO and northeast NM that subsides closer to sunset. For the AZ portion, deep-layer shear will remain weak, but a more northerly orientation to the mid/upper flow should foster convection over the Rim spreading south into the lower deserts. Buoyancy south of the Rim should be moderate, with MLCAPE of 1000-2000 J/kg amid hot temperatures and low to mid 60s surface dew points. Loose multicell clustering may occur as outflows spread south-southwestward. While small to marginally severe hail is possible along the Rim, strong to isolated severe gusts will be the main hazard before convection weakens after sunset. ..Grams/Lyons.. 07/21/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Sun Jul 21 2024 Valid 211200Z - 221200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHWEST... ...SUMMARY... Isolated, marginally severe thunderstorms are possible this afternoon into early evening across parts of central and southern Arizona, and from southern Colorado to northeast New Mexico. ...Southwest... Scattered to widespread thunderstorms are expected this afternoon through sunset within a generally modest north-northwesterly mid/upper flow regime between an anticyclone over the western Great Basin and a low-amplitude trough in the central states. The most likely corridors for thunderstorm development will be across the southern Rockies and the Mogollon Rim. For the CO/NM portion, more favorable wind profiles will exist here, but buoyancy will largely remain weak owing to below-normal surface temperatures. Convection will probably struggle to greatly intensify, but a few updrafts may acquire transient supercell structure and be capable of marginally severe hail during the afternoon. Storms should largely consolidate into multicell clusters moving south-southeastward, with mainly a strong-gust threat over southeast CO and northeast NM that subsides closer to sunset. For the AZ portion, deep-layer shear will remain weak, but a more northerly orientation to the mid/upper flow should foster convection over the Rim spreading south into the lower deserts. Buoyancy south of the Rim should be moderate, with MLCAPE of 1000-2000 J/kg amid hot temperatures and low to mid 60s surface dew points. Loose multicell clustering may occur as outflows spread south-southwestward. While small to marginally severe hail is possible along the Rim, strong to isolated severe gusts will be the main hazard before convection weakens after sunset. ..Grams/Lyons.. 07/21/2024 Read more

000
ABPZ20 KNHC 210513
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 PM PDT Sat Jul 20 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Central and Western East Pacific:
A tropical wave located well to the south of the southern tip of the
Baja California Peninsula is producing a broad area of showers and
thunderstorms. Environmental conditions appear conducive for some
gradual development of this system over the next several days while
it moves westward to west-northwestward at 10 to 15 mph across the
central and western portions of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Kelly

MD 1689 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE FRONT RANGE OF COLORADO
Mesoscale Discussion 1689 NWS Storm Prediction Center Norman OK 0919 PM CDT Sat Jul 20 2024 Areas affected...portions of the Front Range of Colorado Concerning...Severe potential...Watch unlikely Valid 210219Z - 210315Z Probability of Watch Issuance...20 percent SUMMARY...A pair of supercells moving south along the I-25 corridor may pose a risk for hail and severe gusts for a couple more hours tonight. The longevity and spatial extent of the threat is uncertain. DISCUSSION...As of 0210 UTC, a pair of supercells have evolved within the upslope flow regime across eastern CO. These storms have produced reports of measured severe hail and wind gusts over the last hour. Extrapolation places these storms near Denver in the next hour. Around 1000 J/kg of MUCAPE and 35-40 kt of northerly deep-layer shear will remain sufficient for storm organization this evening. Some risk for severe hail and damaging gusts could continue as these storms track along and south of the Metro this evening. A complicating factor is the presence of westward surging outflow from prior convection over the adjacent plains. With the loss of diurnal heating and cooler surface temperatures post outflow, surface stabilization is expected. However, it remains unclear how long it will take for the decrease in instability to affect these storms. Convective trends are being monitored, but the severe risk could persist for another couple of hours in and south of the Denver metro before weakening later this evening. ..Lyons/Gleason.. 07/21/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PUB...BOU... LAT...LON 40310533 40460510 40410478 40200442 39690435 39050461 39010472 38950511 39250538 40180552 40310533 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Jul 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTH-CENTRAL HIGH PLAINS AND EASTERN NC... ...SUMMARY... Isolated, marginally severe storms remain possible this evening over a portion of the south-central High Plains and eastern North Carolina. ...Eastern CO vicinity... A string of broken cells are moving southward across northeast to east-central CO within 30-35 kt mid-level north-northwesterlies per regional VWP data. The lack of observed sounding data ahead of this activity renders uncertainty over potential intensification, but based on marginal MRMS MESH values, it is plausible that this activity may produce marginally severe hail and locally strong gusts for a few more hours, before weakening near the Raton Mesa/Sangre de Cristo Mountains later this evening. ...Eastern NC... Convection has increased somewhat into the coastal plain with measured gusts to around 50 mph over the past hour. While lapse rates are weak, a belt of unidirectional west-southwesterly low to mid-level flow, characterized by 30 kts at 700-mb per the 00Z MHX sounding, could support locally strong gusts capable of tree damage as convection spreads towards the Outer Banks tonight. ...Elsewhere... Convection near the I-40 corridor in west-central OK should slowly sink southward this evening with about 15 kts of low-level southerly inflow. The 00Z OUN sounding is supportive of small to marginally severe hail along with a localized strong gust or two. Slow-moving cells with prominent outflows will persist across the southeast AZ area for a few more hours. 00Z TUS sounding sampled very weak shear, so an organized severe wind threat is not expected. But any pulse cell will be capable of a localized strong gust. ..Grams.. 07/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Jul 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTH-CENTRAL HIGH PLAINS AND EASTERN NC... ...SUMMARY... Isolated, marginally severe storms remain possible this evening over a portion of the south-central High Plains and eastern North Carolina. ...Eastern CO vicinity... A string of broken cells are moving southward across northeast to east-central CO within 30-35 kt mid-level north-northwesterlies per regional VWP data. The lack of observed sounding data ahead of this activity renders uncertainty over potential intensification, but based on marginal MRMS MESH values, it is plausible that this activity may produce marginally severe hail and locally strong gusts for a few more hours, before weakening near the Raton Mesa/Sangre de Cristo Mountains later this evening. ...Eastern NC... Convection has increased somewhat into the coastal plain with measured gusts to around 50 mph over the past hour. While lapse rates are weak, a belt of unidirectional west-southwesterly low to mid-level flow, characterized by 30 kts at 700-mb per the 00Z MHX sounding, could support locally strong gusts capable of tree damage as convection spreads towards the Outer Banks tonight. ...Elsewhere... Convection near the I-40 corridor in west-central OK should slowly sink southward this evening with about 15 kts of low-level southerly inflow. The 00Z OUN sounding is supportive of small to marginally severe hail along with a localized strong gust or two. Slow-moving cells with prominent outflows will persist across the southeast AZ area for a few more hours. 00Z TUS sounding sampled very weak shear, so an organized severe wind threat is not expected. But any pulse cell will be capable of a localized strong gust. ..Grams.. 07/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Jul 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTH-CENTRAL HIGH PLAINS AND EASTERN NC... ...SUMMARY... Isolated, marginally severe storms remain possible this evening over a portion of the south-central High Plains and eastern North Carolina. ...Eastern CO vicinity... A string of broken cells are moving southward across northeast to east-central CO within 30-35 kt mid-level north-northwesterlies per regional VWP data. The lack of observed sounding data ahead of this activity renders uncertainty over potential intensification, but based on marginal MRMS MESH values, it is plausible that this activity may produce marginally severe hail and locally strong gusts for a few more hours, before weakening near the Raton Mesa/Sangre de Cristo Mountains later this evening. ...Eastern NC... Convection has increased somewhat into the coastal plain with measured gusts to around 50 mph over the past hour. While lapse rates are weak, a belt of unidirectional west-southwesterly low to mid-level flow, characterized by 30 kts at 700-mb per the 00Z MHX sounding, could support locally strong gusts capable of tree damage as convection spreads towards the Outer Banks tonight. ...Elsewhere... Convection near the I-40 corridor in west-central OK should slowly sink southward this evening with about 15 kts of low-level southerly inflow. The 00Z OUN sounding is supportive of small to marginally severe hail along with a localized strong gust or two. Slow-moving cells with prominent outflows will persist across the southeast AZ area for a few more hours. 00Z TUS sounding sampled very weak shear, so an organized severe wind threat is not expected. But any pulse cell will be capable of a localized strong gust. ..Grams.. 07/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Jul 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTH-CENTRAL HIGH PLAINS AND EASTERN NC... ...SUMMARY... Isolated, marginally severe storms remain possible this evening over a portion of the south-central High Plains and eastern North Carolina. ...Eastern CO vicinity... A string of broken cells are moving southward across northeast to east-central CO within 30-35 kt mid-level north-northwesterlies per regional VWP data. The lack of observed sounding data ahead of this activity renders uncertainty over potential intensification, but based on marginal MRMS MESH values, it is plausible that this activity may produce marginally severe hail and locally strong gusts for a few more hours, before weakening near the Raton Mesa/Sangre de Cristo Mountains later this evening. ...Eastern NC... Convection has increased somewhat into the coastal plain with measured gusts to around 50 mph over the past hour. While lapse rates are weak, a belt of unidirectional west-southwesterly low to mid-level flow, characterized by 30 kts at 700-mb per the 00Z MHX sounding, could support locally strong gusts capable of tree damage as convection spreads towards the Outer Banks tonight. ...Elsewhere... Convection near the I-40 corridor in west-central OK should slowly sink southward this evening with about 15 kts of low-level southerly inflow. The 00Z OUN sounding is supportive of small to marginally severe hail along with a localized strong gust or two. Slow-moving cells with prominent outflows will persist across the southeast AZ area for a few more hours. 00Z TUS sounding sampled very weak shear, so an organized severe wind threat is not expected. But any pulse cell will be capable of a localized strong gust. ..Grams.. 07/21/2024 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0758 PM CDT Sat Jul 20 2024 Valid 210100Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN THE SOUTH-CENTRAL HIGH PLAINS AND EASTERN NC... ...SUMMARY... Isolated, marginally severe storms remain possible this evening over a portion of the south-central High Plains and eastern North Carolina. ...Eastern CO vicinity... A string of broken cells are moving southward across northeast to east-central CO within 30-35 kt mid-level north-northwesterlies per regional VWP data. The lack of observed sounding data ahead of this activity renders uncertainty over potential intensification, but based on marginal MRMS MESH values, it is plausible that this activity may produce marginally severe hail and locally strong gusts for a few more hours, before weakening near the Raton Mesa/Sangre de Cristo Mountains later this evening. ...Eastern NC... Convection has increased somewhat into the coastal plain with measured gusts to around 50 mph over the past hour. While lapse rates are weak, a belt of unidirectional west-southwesterly low to mid-level flow, characterized by 30 kts at 700-mb per the 00Z MHX sounding, could support locally strong gusts capable of tree damage as convection spreads towards the Outer Banks tonight. ...Elsewhere... Convection near the I-40 corridor in west-central OK should slowly sink southward this evening with about 15 kts of low-level southerly inflow. The 00Z OUN sounding is supportive of small to marginally severe hail along with a localized strong gust or two. Slow-moving cells with prominent outflows will persist across the southeast AZ area for a few more hours. 00Z TUS sounding sampled very weak shear, so an organized severe wind threat is not expected. But any pulse cell will be capable of a localized strong gust. ..Grams.. 07/21/2024 Read more

No watches are valid as of Sat Jul 20 23:46:02 UTC 2024.

No Mesoscale Discussions are in effect as of Sat Jul 20 23:46:02 UTC 2024.

000
ABPZ20 KNHC 202318
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Sat Jul 20 2024

For the eastern North Pacific...east of 140 degrees west longitude:

Central and Western East Pacific:
Shower activity associated with a tropical wave located well to the
south of the southern tip of the Baja California Peninsula has
become a little more concentrated since yesterday. Environmental
conditions appear conducive for some gradual development of this
system over the next several days while it moves westward to
west-northwestward at 10 to 15 mph across the central and western
portions of the basin.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Beven

MD 1688 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF SOUTHEAST COLORADO AND FAR SOUTHWEST KANSAS.
Mesoscale Discussion 1688 NWS Storm Prediction Center Norman OK 0516 PM CDT Sat Jul 20 2024 Areas affected...portions of southeast colorado and far southwest Kansas. Concerning...Severe potential...Watch unlikely Valid 202216Z - 202345Z Probability of Watch Issuance...20 percent SUMMARY...Damaging gusts and hail will be possible with isolated thunderstorms this evening. A WW appears unlikely though conditions will be monitored. DISCUSSION...As of 2210 UTC regional radar imagery showed isolated thunderstorms ongoing across the foothills of southeast CO and farther east over the High Plains. Over the last hour, storms have gradually increased in coverage and intensity within the weak northeasterly upslope flow regime. While not overly robust, modest mid-level lapse rates and 50s F dewpoints are supporting moderate buoyancy. Flow aloft is also not overly strong, but 25-30 kt of effective shear should be sufficient for brief storm organization with multicells and transient supercell structures. As storms continue to develop they should move off the higher terrain this evening. Isolated damaging gusts and some hail are possible with the stronger cores. However, storm organization appears transient and the lack of greater forcing aloft will keep coverage limited. This should keep the severe risk marginal and a WW is unlikely. ..Lyons/Gleason.. 07/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DDC...GLD...AMA...PUB...BOU...ABQ... LAT...LON 39420311 39350248 38340163 37210161 36950211 36880319 37000450 37900496 38840497 39190460 39420311 Read more

MD 1687 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR PORTIONS OF THE CENTRAL HIGH PLAINS
Mesoscale Discussion 1687 NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Jul 20 2024 Areas affected...Portions of the central High Plains Concerning...Severe potential...Watch unlikely Valid 201957Z - 202230Z Probability of Watch Issuance...20 percent SUMMARY...Thunderstorms are expected to increase in coverage and intensity across eastern Wyoming and Colorado and the Nebraska Panhandle through the afternoon and evening hours posing a threat of severe hail and wind gusts. Given the isolated nature of the threat, a severe thunderstorm watch is unlikely. DISCUSSION...With strong heating across the region, thunderstorms have initiated ahead of a weak midlevel impulse moving southeastward into northern Wyoming (per latest water vapor imagery). These storms are developing in an environment characterized by ~1000 J/kg of MLCAPE and ~25 knots of effective shear, supporting primarily multicell storms with some short-lived supercell characteristics. As such, severe hail and damaging winds may be possible, but the threat is expected to remain too marginal and isolated to warrant a watch. ..Jirak/Smith.. 07/20/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...GLD...BOU...CYS... LAT...LON 39530440 40280498 41600557 42660562 43070547 43410485 43280394 42860305 42310252 41010225 40070234 39520249 39250317 39190399 39530440 Read more