Aggregator

Issued at 200 AM MST Thu Jul 25 2024 000 WTPZ32 KNHC 250833 TCPEP2 BULLETIN Tropical Storm Bud Advisory Number 3 NWS National Hurricane Center Miami FL EP022024 200 AM MST Thu Jul 25 2024 ...BUD A LITTLE STRONGER... SUMMARY OF 200 AM MST...0900 UTC...INFORMATION ---------------------------------------------- LOCATION...17.9N 114.3W ABOUT 445 MI...720 KM SW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...WNW OR 295 DEGREES AT 12 MPH...19 KM/H MINIMUM CENTRAL PRESSURE...1005 MB...29.68 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 200 AM MST (0900 UTC), the center of Tropical Storm Bud was located near latitude 17.9 North, longitude 114.3 West. Bud is moving toward the west-northwest near 12 mph (19 km/h). A turn toward the west is expected later today, followed by a slower southwestward motion on Friday and Friday night. Recent satellite wind data indicate that maximum sustained winds are now near 45 mph (75 km/h) with higher gusts. Bud is expected to begin weakening later today or tonight, and the system is forecast to dissipate by the weekend. Tropical-storm-force winds extend outward up to 45 miles (75 km) from the center. A Mexican Navy automated station on Isla Clarion recently reported a wind gust of 44 mph (71 km/h). The estimated minimum central pressure is 1005 mb (29.68 inches). HAZARDS AFFECTING LAND ---------------------- None NEXT ADVISORY ------------- Next complete advisory at 800 AM MST. $$ Forecaster Beven

...BUD A LITTLE STRONGER... As of 2:00 AM MST Thu Jul 25 the center of Bud was located near 17.9, -114.3 with movement WNW at 12 mph. The minimum central pressure was 1005 mb with maximum sustained winds of about 45 mph.

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Thu Jul 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS VICINITY... ...SUMMARY... Strong to severe thunderstorms are possible across portions of the northern Plains vicinity on Saturday. ...Northern Plains... An upper low will be centered over northern Saskatchewan/Manitoba on Saturday, with the associated northern stream upper trough extending southwest from the upper low into MT. The northern stream trough will develop east across the Canadian Prairies, clipping the northern Plains. Meanwhile, another convectively enhanced shortwave impulse embedded in westerly flow will migrate eastward across WY into the SD/NE vicinity. At the surface, a cold front is forecast to shift southeast across the northern Plains during the evening/overnight hours. Ahead of the front, south/southeasterly low-level flow will aid in northeastward transport of richer boundary layer moisture. Convection will likely develop ahead of the cold front in ND during the evening and into the overnight hours. Additional thunderstorm clusters related to the shortwave impulse emanating out of WY are expected by late afternoon/early evening. Aided by 30-40 kt southerly low-level jet, this activity may also form upscale into an eastward propagating MCS across parts of SD/NE. At least isolated severe thunderstorms appear possible given favorable thermodynamic profiles and effective shear magnitudes greater than 30 kt. Timing of shortwave trough ejection and surface cold front position, as well as questions regarding a recovering airmass in the wake of an early day exiting shortwave trough still lend to plenty of uncertainty for the Day 3/Saturday period. However, greater severe probabilities may be needed in subsequent outlooks as these finer scale details become better resolved in the coming days. ..Leitman.. 07/25/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Thu Jul 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS VICINITY... ...SUMMARY... Strong to severe thunderstorms are possible across portions of the northern Plains vicinity on Saturday. ...Northern Plains... An upper low will be centered over northern Saskatchewan/Manitoba on Saturday, with the associated northern stream upper trough extending southwest from the upper low into MT. The northern stream trough will develop east across the Canadian Prairies, clipping the northern Plains. Meanwhile, another convectively enhanced shortwave impulse embedded in westerly flow will migrate eastward across WY into the SD/NE vicinity. At the surface, a cold front is forecast to shift southeast across the northern Plains during the evening/overnight hours. Ahead of the front, south/southeasterly low-level flow will aid in northeastward transport of richer boundary layer moisture. Convection will likely develop ahead of the cold front in ND during the evening and into the overnight hours. Additional thunderstorm clusters related to the shortwave impulse emanating out of WY are expected by late afternoon/early evening. Aided by 30-40 kt southerly low-level jet, this activity may also form upscale into an eastward propagating MCS across parts of SD/NE. At least isolated severe thunderstorms appear possible given favorable thermodynamic profiles and effective shear magnitudes greater than 30 kt. Timing of shortwave trough ejection and surface cold front position, as well as questions regarding a recovering airmass in the wake of an early day exiting shortwave trough still lend to plenty of uncertainty for the Day 3/Saturday period. However, greater severe probabilities may be needed in subsequent outlooks as these finer scale details become better resolved in the coming days. ..Leitman.. 07/25/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Thu Jul 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS VICINITY... ...SUMMARY... Strong to severe thunderstorms are possible across portions of the northern Plains vicinity on Saturday. ...Northern Plains... An upper low will be centered over northern Saskatchewan/Manitoba on Saturday, with the associated northern stream upper trough extending southwest from the upper low into MT. The northern stream trough will develop east across the Canadian Prairies, clipping the northern Plains. Meanwhile, another convectively enhanced shortwave impulse embedded in westerly flow will migrate eastward across WY into the SD/NE vicinity. At the surface, a cold front is forecast to shift southeast across the northern Plains during the evening/overnight hours. Ahead of the front, south/southeasterly low-level flow will aid in northeastward transport of richer boundary layer moisture. Convection will likely develop ahead of the cold front in ND during the evening and into the overnight hours. Additional thunderstorm clusters related to the shortwave impulse emanating out of WY are expected by late afternoon/early evening. Aided by 30-40 kt southerly low-level jet, this activity may also form upscale into an eastward propagating MCS across parts of SD/NE. At least isolated severe thunderstorms appear possible given favorable thermodynamic profiles and effective shear magnitudes greater than 30 kt. Timing of shortwave trough ejection and surface cold front position, as well as questions regarding a recovering airmass in the wake of an early day exiting shortwave trough still lend to plenty of uncertainty for the Day 3/Saturday period. However, greater severe probabilities may be needed in subsequent outlooks as these finer scale details become better resolved in the coming days. ..Leitman.. 07/25/2024 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0208 AM CDT Thu Jul 25 2024 Valid 271200Z - 281200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN PLAINS VICINITY... ...SUMMARY... Strong to severe thunderstorms are possible across portions of the northern Plains vicinity on Saturday. ...Northern Plains... An upper low will be centered over northern Saskatchewan/Manitoba on Saturday, with the associated northern stream upper trough extending southwest from the upper low into MT. The northern stream trough will develop east across the Canadian Prairies, clipping the northern Plains. Meanwhile, another convectively enhanced shortwave impulse embedded in westerly flow will migrate eastward across WY into the SD/NE vicinity. At the surface, a cold front is forecast to shift southeast across the northern Plains during the evening/overnight hours. Ahead of the front, south/southeasterly low-level flow will aid in northeastward transport of richer boundary layer moisture. Convection will likely develop ahead of the cold front in ND during the evening and into the overnight hours. Additional thunderstorm clusters related to the shortwave impulse emanating out of WY are expected by late afternoon/early evening. Aided by 30-40 kt southerly low-level jet, this activity may also form upscale into an eastward propagating MCS across parts of SD/NE. At least isolated severe thunderstorms appear possible given favorable thermodynamic profiles and effective shear magnitudes greater than 30 kt. Timing of shortwave trough ejection and surface cold front position, as well as questions regarding a recovering airmass in the wake of an early day exiting shortwave trough still lend to plenty of uncertainty for the Day 3/Saturday period. However, greater severe probabilities may be needed in subsequent outlooks as these finer scale details become better resolved in the coming days. ..Leitman.. 07/25/2024 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...Synopsis... As a mid-level shortwave trough moves onshore to the California coast and into Nevada tomorrow, isolated dry thunderstorms are expected across northern Utah into southeastern Idaho and southwestern Wyoming. Elevated fire-weather conditions are also expected across portions of the Northwest, including northern California into southwestern Oregon, western portions of the Upper Snake River Region in Idaho, and far northern Montana. ...Northern Utah into Southern Idaho and Southwestern Wyoming... Isolated dry thunderstorms are expected as a mid-level trough and associated jet streak approaches the California coast. Hot, dry boundary-layer profiles, coupled with 35-40 kt mean wind speed estimates for storm motions, will result in little wetting rainfall occurring over receptive fuels. A mix of dry and wet thunderstorms are possible further into Wyoming, but fuels in the region are less receptive to ignitions. There may be a chance for isolated dry thunderstorms in far southern Montana, but the threat appears to be too localized to include a highlight area at this time. ...Northwest... Elevated fire-weather conditions will persist across portions of southern Oregon and into northwestern California with the approaching trough. The strongest winds will likely be confined to the Fremont mountains and Modoc Plateau. Portions of northern Montana could also see elevated fire-weather conditions on Friday, where prolonged dry and windy conditions will overlap with receptive fuels as a mid-level jet extending from Saskatchewan into Montana begins to exit the region and progress eastward. The most pronounced region for elevated conditions is expected to be across portions of the Snake River Plain and into the Upper Snake Region, where there is significant overlap between 20-25 kt surface winds, < 15% RH, and receptive fuels. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...Synopsis... As a mid-level shortwave trough moves onshore to the California coast and into Nevada tomorrow, isolated dry thunderstorms are expected across northern Utah into southeastern Idaho and southwestern Wyoming. Elevated fire-weather conditions are also expected across portions of the Northwest, including northern California into southwestern Oregon, western portions of the Upper Snake River Region in Idaho, and far northern Montana. ...Northern Utah into Southern Idaho and Southwestern Wyoming... Isolated dry thunderstorms are expected as a mid-level trough and associated jet streak approaches the California coast. Hot, dry boundary-layer profiles, coupled with 35-40 kt mean wind speed estimates for storm motions, will result in little wetting rainfall occurring over receptive fuels. A mix of dry and wet thunderstorms are possible further into Wyoming, but fuels in the region are less receptive to ignitions. There may be a chance for isolated dry thunderstorms in far southern Montana, but the threat appears to be too localized to include a highlight area at this time. ...Northwest... Elevated fire-weather conditions will persist across portions of southern Oregon and into northwestern California with the approaching trough. The strongest winds will likely be confined to the Fremont mountains and Modoc Plateau. Portions of northern Montana could also see elevated fire-weather conditions on Friday, where prolonged dry and windy conditions will overlap with receptive fuels as a mid-level jet extending from Saskatchewan into Montana begins to exit the region and progress eastward. The most pronounced region for elevated conditions is expected to be across portions of the Snake River Plain and into the Upper Snake Region, where there is significant overlap between 20-25 kt surface winds, < 15% RH, and receptive fuels. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...Synopsis... As a mid-level shortwave trough moves onshore to the California coast and into Nevada tomorrow, isolated dry thunderstorms are expected across northern Utah into southeastern Idaho and southwestern Wyoming. Elevated fire-weather conditions are also expected across portions of the Northwest, including northern California into southwestern Oregon, western portions of the Upper Snake River Region in Idaho, and far northern Montana. ...Northern Utah into Southern Idaho and Southwestern Wyoming... Isolated dry thunderstorms are expected as a mid-level trough and associated jet streak approaches the California coast. Hot, dry boundary-layer profiles, coupled with 35-40 kt mean wind speed estimates for storm motions, will result in little wetting rainfall occurring over receptive fuels. A mix of dry and wet thunderstorms are possible further into Wyoming, but fuels in the region are less receptive to ignitions. There may be a chance for isolated dry thunderstorms in far southern Montana, but the threat appears to be too localized to include a highlight area at this time. ...Northwest... Elevated fire-weather conditions will persist across portions of southern Oregon and into northwestern California with the approaching trough. The strongest winds will likely be confined to the Fremont mountains and Modoc Plateau. Portions of northern Montana could also see elevated fire-weather conditions on Friday, where prolonged dry and windy conditions will overlap with receptive fuels as a mid-level jet extending from Saskatchewan into Montana begins to exit the region and progress eastward. The most pronounced region for elevated conditions is expected to be across portions of the Snake River Plain and into the Upper Snake Region, where there is significant overlap between 20-25 kt surface winds, < 15% RH, and receptive fuels. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0201 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...Synopsis... As a mid-level shortwave trough moves onshore to the California coast and into Nevada tomorrow, isolated dry thunderstorms are expected across northern Utah into southeastern Idaho and southwestern Wyoming. Elevated fire-weather conditions are also expected across portions of the Northwest, including northern California into southwestern Oregon, western portions of the Upper Snake River Region in Idaho, and far northern Montana. ...Northern Utah into Southern Idaho and Southwestern Wyoming... Isolated dry thunderstorms are expected as a mid-level trough and associated jet streak approaches the California coast. Hot, dry boundary-layer profiles, coupled with 35-40 kt mean wind speed estimates for storm motions, will result in little wetting rainfall occurring over receptive fuels. A mix of dry and wet thunderstorms are possible further into Wyoming, but fuels in the region are less receptive to ignitions. There may be a chance for isolated dry thunderstorms in far southern Montana, but the threat appears to be too localized to include a highlight area at this time. ...Northwest... Elevated fire-weather conditions will persist across portions of southern Oregon and into northwestern California with the approaching trough. The strongest winds will likely be confined to the Fremont mountains and Modoc Plateau. Portions of northern Montana could also see elevated fire-weather conditions on Friday, where prolonged dry and windy conditions will overlap with receptive fuels as a mid-level jet extending from Saskatchewan into Montana begins to exit the region and progress eastward. The most pronounced region for elevated conditions is expected to be across portions of the Snake River Plain and into the Upper Snake Region, where there is significant overlap between 20-25 kt surface winds, < 15% RH, and receptive fuels. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1248 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...Synopsis... Isolated dry thunderstorms are anticipated across portions of southern Idaho into southwestern Montana as an upper-level trough progresses eastward across the Northwest. Additionally, elevated fire-weather conditions are expected across the southern Cascades, portions of northern Montana, and the northern Great Plains. ...Pacific Northwest... As an upper-level trough is forecast to progress eastward out of the Pacific Northwest and into Montana, isolated dry thunderstorms are expected across southeastern Idaho and into southwestern Montana over receptive fuels. Some trimming of the previous forecast area, particularly over southwestern Idaho, was necessary after significant wetting rainfall occurred the previous day. Additionally, current forecast guidance suggests a mix of both wet and dry thunderstorms, precluding the introduction of a scattered dry thunder area despite widespread thunderstorm coverage. Forecast profiles across southwestern Montana show deep inverted-v boundary layers supportive of gusty thunderstorm outflow that could contribute to wildfire spread with both existing fires and new lightning ignitions. Elevated fire-weather conditions are expected to occur over the southern Cascades, especially where local gap flow enhanced winds could contribute to wildfire spread with existing fires. Some trimming of the previous forecast areas was necessary to account for wetting rainfall occurring the previous day, leaving fuels less receptive to ignition. Some elevated fire-weather conditions are also possible in portions of north-central Montana, but the overlap of stronger surface winds/low relative humidity and receptive fuels is somewhat narrow. ...Northern Great Plains... Elevated fire-weather conditions are anticipated, particularly along portions of western Montana and Wyoming, into eastern Nebraska and the Dakotas. Strong southerly flow, coupled with hot, dry boundary layer profiles, are expected to persist for much of the afternoon and into the evening. Fuels in this region will be at or exceed the 90th percentile for ERCs, but conditions are expected to remain below critical criteria for wind and relative humidity. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1248 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...Synopsis... Isolated dry thunderstorms are anticipated across portions of southern Idaho into southwestern Montana as an upper-level trough progresses eastward across the Northwest. Additionally, elevated fire-weather conditions are expected across the southern Cascades, portions of northern Montana, and the northern Great Plains. ...Pacific Northwest... As an upper-level trough is forecast to progress eastward out of the Pacific Northwest and into Montana, isolated dry thunderstorms are expected across southeastern Idaho and into southwestern Montana over receptive fuels. Some trimming of the previous forecast area, particularly over southwestern Idaho, was necessary after significant wetting rainfall occurred the previous day. Additionally, current forecast guidance suggests a mix of both wet and dry thunderstorms, precluding the introduction of a scattered dry thunder area despite widespread thunderstorm coverage. Forecast profiles across southwestern Montana show deep inverted-v boundary layers supportive of gusty thunderstorm outflow that could contribute to wildfire spread with both existing fires and new lightning ignitions. Elevated fire-weather conditions are expected to occur over the southern Cascades, especially where local gap flow enhanced winds could contribute to wildfire spread with existing fires. Some trimming of the previous forecast areas was necessary to account for wetting rainfall occurring the previous day, leaving fuels less receptive to ignition. Some elevated fire-weather conditions are also possible in portions of north-central Montana, but the overlap of stronger surface winds/low relative humidity and receptive fuels is somewhat narrow. ...Northern Great Plains... Elevated fire-weather conditions are anticipated, particularly along portions of western Montana and Wyoming, into eastern Nebraska and the Dakotas. Strong southerly flow, coupled with hot, dry boundary layer profiles, are expected to persist for much of the afternoon and into the evening. Fuels in this region will be at or exceed the 90th percentile for ERCs, but conditions are expected to remain below critical criteria for wind and relative humidity. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1248 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...Synopsis... Isolated dry thunderstorms are anticipated across portions of southern Idaho into southwestern Montana as an upper-level trough progresses eastward across the Northwest. Additionally, elevated fire-weather conditions are expected across the southern Cascades, portions of northern Montana, and the northern Great Plains. ...Pacific Northwest... As an upper-level trough is forecast to progress eastward out of the Pacific Northwest and into Montana, isolated dry thunderstorms are expected across southeastern Idaho and into southwestern Montana over receptive fuels. Some trimming of the previous forecast area, particularly over southwestern Idaho, was necessary after significant wetting rainfall occurred the previous day. Additionally, current forecast guidance suggests a mix of both wet and dry thunderstorms, precluding the introduction of a scattered dry thunder area despite widespread thunderstorm coverage. Forecast profiles across southwestern Montana show deep inverted-v boundary layers supportive of gusty thunderstorm outflow that could contribute to wildfire spread with both existing fires and new lightning ignitions. Elevated fire-weather conditions are expected to occur over the southern Cascades, especially where local gap flow enhanced winds could contribute to wildfire spread with existing fires. Some trimming of the previous forecast areas was necessary to account for wetting rainfall occurring the previous day, leaving fuels less receptive to ignition. Some elevated fire-weather conditions are also possible in portions of north-central Montana, but the overlap of stronger surface winds/low relative humidity and receptive fuels is somewhat narrow. ...Northern Great Plains... Elevated fire-weather conditions are anticipated, particularly along portions of western Montana and Wyoming, into eastern Nebraska and the Dakotas. Strong southerly flow, coupled with hot, dry boundary layer profiles, are expected to persist for much of the afternoon and into the evening. Fuels in this region will be at or exceed the 90th percentile for ERCs, but conditions are expected to remain below critical criteria for wind and relative humidity. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1248 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...Synopsis... Isolated dry thunderstorms are anticipated across portions of southern Idaho into southwestern Montana as an upper-level trough progresses eastward across the Northwest. Additionally, elevated fire-weather conditions are expected across the southern Cascades, portions of northern Montana, and the northern Great Plains. ...Pacific Northwest... As an upper-level trough is forecast to progress eastward out of the Pacific Northwest and into Montana, isolated dry thunderstorms are expected across southeastern Idaho and into southwestern Montana over receptive fuels. Some trimming of the previous forecast area, particularly over southwestern Idaho, was necessary after significant wetting rainfall occurred the previous day. Additionally, current forecast guidance suggests a mix of both wet and dry thunderstorms, precluding the introduction of a scattered dry thunder area despite widespread thunderstorm coverage. Forecast profiles across southwestern Montana show deep inverted-v boundary layers supportive of gusty thunderstorm outflow that could contribute to wildfire spread with both existing fires and new lightning ignitions. Elevated fire-weather conditions are expected to occur over the southern Cascades, especially where local gap flow enhanced winds could contribute to wildfire spread with existing fires. Some trimming of the previous forecast areas was necessary to account for wetting rainfall occurring the previous day, leaving fuels less receptive to ignition. Some elevated fire-weather conditions are also possible in portions of north-central Montana, but the overlap of stronger surface winds/low relative humidity and receptive fuels is somewhat narrow. ...Northern Great Plains... Elevated fire-weather conditions are anticipated, particularly along portions of western Montana and Wyoming, into eastern Nebraska and the Dakotas. Strong southerly flow, coupled with hot, dry boundary layer profiles, are expected to persist for much of the afternoon and into the evening. Fuels in this region will be at or exceed the 90th percentile for ERCs, but conditions are expected to remain below critical criteria for wind and relative humidity. ..Halbert/Lyons.. 07/25/2024 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST MONTANA AND NORTHEAST WYOMING INTO WESTERN SOUTH DAKOTA...AND ACROSS FAR EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern High Plains and far eastern North Dakota into northwest Minnesota on Friday. ...Synopsis... A more progressive upper pattern in expected on Friday as an upper trough develops westward across the western U.S. This will shunt the Plains upper ridge east, extending from the Great Lakes, southward to the Gulf Coast states. While the upper trough envelops much of the western U.S., an upper anticyclone will remain centered over northern Baja, and extend northeast into AZ/NM. At the surface, a cold front will extend southward across the western Dakotas early in the day. The northern extent of the front will develop east toward the ND/MN border by 00z, while the SD portion of the front stalls and becomes diffuse. Surface high pressure over the Great Lakes will maintain a mostly dry airmass from the Ohio Valley into the Northeast in the wake of a prior cold frontal passage. Meanwhile, a baroclinic zone over the Upper Midwest will allow for rich boundary layer moisture beneath the eastward-develop upper ridge. Southwesterly low-level flow across northwest Mexico into AZ will bring modest boundary-layer moisture into the southern AZ deserts as well. ...WY into western SD and Vicinity... Boundary-layer moisture is expected to modestly return in the wake of the morning cold front as the boundary stalls over western/central SD. Low-level flow is expected to become east/southeasterly during the afternoon, allowing for modest moisture return and destabilization in this post-frontal upslope flow regime. Forecast guidance suggests at least isolated thunderstorms will develop as large-scale ascent increases in response to a shortwave impulse migrating through southwesterly flow, generating modest height falls across the region. Forecast soundings indicate a deeply mixed boundary layer with inverted-v thermodynamic sub-cloud profiles amid 25 kt effective shear magnitudes. Isolated strong/severe gusts may accompany thunderstorm activity during the evening, especially if clustering/outflow consolidation occurs. ...Eastern ND into MN... Thunderstorms are expected to develop ahead of the eastward-advancing cold front by late Friday afternoon as the boundary impinges on richer boundary layer moisture. Initial capping should erode as the upper ridge shifts east toward the Great Lakes, resulting in falling heights/cooling aloft while warm advection continues in the low-levels. Even if weak capping is maintained, elevated convection is still expected. A narrow corridor of MLCAPE up to 2500 J/kg is forecast amid effective shear magnitudes around 35 kt, supporting robust updrafts and marginal supercells. Isolated hail will be possible in addition locally strong gusts. ...AZ... Modest boundary layer moisture and steep lapse rates will support around 500-1000 J/kg MLCAPE. Thunderstorms will once again develop over higher terrain and move south during the evening. Mid and upper-level flow will be a bit more northerly compared to the prior few days and fairly weak (generally less than 15 kt). Nevertheless, deep mixing and inverted-v thermodynamic profiles will support sporadic strong gusts. Given somewhat less favorable flow compared to recent days, will hold off on marginal wind probabilities at this time. ..Leitman.. 07/25/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST MONTANA AND NORTHEAST WYOMING INTO WESTERN SOUTH DAKOTA...AND ACROSS FAR EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern High Plains and far eastern North Dakota into northwest Minnesota on Friday. ...Synopsis... A more progressive upper pattern in expected on Friday as an upper trough develops westward across the western U.S. This will shunt the Plains upper ridge east, extending from the Great Lakes, southward to the Gulf Coast states. While the upper trough envelops much of the western U.S., an upper anticyclone will remain centered over northern Baja, and extend northeast into AZ/NM. At the surface, a cold front will extend southward across the western Dakotas early in the day. The northern extent of the front will develop east toward the ND/MN border by 00z, while the SD portion of the front stalls and becomes diffuse. Surface high pressure over the Great Lakes will maintain a mostly dry airmass from the Ohio Valley into the Northeast in the wake of a prior cold frontal passage. Meanwhile, a baroclinic zone over the Upper Midwest will allow for rich boundary layer moisture beneath the eastward-develop upper ridge. Southwesterly low-level flow across northwest Mexico into AZ will bring modest boundary-layer moisture into the southern AZ deserts as well. ...WY into western SD and Vicinity... Boundary-layer moisture is expected to modestly return in the wake of the morning cold front as the boundary stalls over western/central SD. Low-level flow is expected to become east/southeasterly during the afternoon, allowing for modest moisture return and destabilization in this post-frontal upslope flow regime. Forecast guidance suggests at least isolated thunderstorms will develop as large-scale ascent increases in response to a shortwave impulse migrating through southwesterly flow, generating modest height falls across the region. Forecast soundings indicate a deeply mixed boundary layer with inverted-v thermodynamic sub-cloud profiles amid 25 kt effective shear magnitudes. Isolated strong/severe gusts may accompany thunderstorm activity during the evening, especially if clustering/outflow consolidation occurs. ...Eastern ND into MN... Thunderstorms are expected to develop ahead of the eastward-advancing cold front by late Friday afternoon as the boundary impinges on richer boundary layer moisture. Initial capping should erode as the upper ridge shifts east toward the Great Lakes, resulting in falling heights/cooling aloft while warm advection continues in the low-levels. Even if weak capping is maintained, elevated convection is still expected. A narrow corridor of MLCAPE up to 2500 J/kg is forecast amid effective shear magnitudes around 35 kt, supporting robust updrafts and marginal supercells. Isolated hail will be possible in addition locally strong gusts. ...AZ... Modest boundary layer moisture and steep lapse rates will support around 500-1000 J/kg MLCAPE. Thunderstorms will once again develop over higher terrain and move south during the evening. Mid and upper-level flow will be a bit more northerly compared to the prior few days and fairly weak (generally less than 15 kt). Nevertheless, deep mixing and inverted-v thermodynamic profiles will support sporadic strong gusts. Given somewhat less favorable flow compared to recent days, will hold off on marginal wind probabilities at this time. ..Leitman.. 07/25/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST MONTANA AND NORTHEAST WYOMING INTO WESTERN SOUTH DAKOTA...AND ACROSS FAR EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern High Plains and far eastern North Dakota into northwest Minnesota on Friday. ...Synopsis... A more progressive upper pattern in expected on Friday as an upper trough develops westward across the western U.S. This will shunt the Plains upper ridge east, extending from the Great Lakes, southward to the Gulf Coast states. While the upper trough envelops much of the western U.S., an upper anticyclone will remain centered over northern Baja, and extend northeast into AZ/NM. At the surface, a cold front will extend southward across the western Dakotas early in the day. The northern extent of the front will develop east toward the ND/MN border by 00z, while the SD portion of the front stalls and becomes diffuse. Surface high pressure over the Great Lakes will maintain a mostly dry airmass from the Ohio Valley into the Northeast in the wake of a prior cold frontal passage. Meanwhile, a baroclinic zone over the Upper Midwest will allow for rich boundary layer moisture beneath the eastward-develop upper ridge. Southwesterly low-level flow across northwest Mexico into AZ will bring modest boundary-layer moisture into the southern AZ deserts as well. ...WY into western SD and Vicinity... Boundary-layer moisture is expected to modestly return in the wake of the morning cold front as the boundary stalls over western/central SD. Low-level flow is expected to become east/southeasterly during the afternoon, allowing for modest moisture return and destabilization in this post-frontal upslope flow regime. Forecast guidance suggests at least isolated thunderstorms will develop as large-scale ascent increases in response to a shortwave impulse migrating through southwesterly flow, generating modest height falls across the region. Forecast soundings indicate a deeply mixed boundary layer with inverted-v thermodynamic sub-cloud profiles amid 25 kt effective shear magnitudes. Isolated strong/severe gusts may accompany thunderstorm activity during the evening, especially if clustering/outflow consolidation occurs. ...Eastern ND into MN... Thunderstorms are expected to develop ahead of the eastward-advancing cold front by late Friday afternoon as the boundary impinges on richer boundary layer moisture. Initial capping should erode as the upper ridge shifts east toward the Great Lakes, resulting in falling heights/cooling aloft while warm advection continues in the low-levels. Even if weak capping is maintained, elevated convection is still expected. A narrow corridor of MLCAPE up to 2500 J/kg is forecast amid effective shear magnitudes around 35 kt, supporting robust updrafts and marginal supercells. Isolated hail will be possible in addition locally strong gusts. ...AZ... Modest boundary layer moisture and steep lapse rates will support around 500-1000 J/kg MLCAPE. Thunderstorms will once again develop over higher terrain and move south during the evening. Mid and upper-level flow will be a bit more northerly compared to the prior few days and fairly weak (generally less than 15 kt). Nevertheless, deep mixing and inverted-v thermodynamic profiles will support sporadic strong gusts. Given somewhat less favorable flow compared to recent days, will hold off on marginal wind probabilities at this time. ..Leitman.. 07/25/2024 Read more

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1224 AM CDT Thu Jul 25 2024 Valid 261200Z - 271200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR SOUTHEAST MONTANA AND NORTHEAST WYOMING INTO WESTERN SOUTH DAKOTA...AND ACROSS FAR EASTERN NORTH DAKOTA INTO NORTHWEST MINNESOTA... ...SUMMARY... Isolated severe thunderstorms are possible across parts of the northern High Plains and far eastern North Dakota into northwest Minnesota on Friday. ...Synopsis... A more progressive upper pattern in expected on Friday as an upper trough develops westward across the western U.S. This will shunt the Plains upper ridge east, extending from the Great Lakes, southward to the Gulf Coast states. While the upper trough envelops much of the western U.S., an upper anticyclone will remain centered over northern Baja, and extend northeast into AZ/NM. At the surface, a cold front will extend southward across the western Dakotas early in the day. The northern extent of the front will develop east toward the ND/MN border by 00z, while the SD portion of the front stalls and becomes diffuse. Surface high pressure over the Great Lakes will maintain a mostly dry airmass from the Ohio Valley into the Northeast in the wake of a prior cold frontal passage. Meanwhile, a baroclinic zone over the Upper Midwest will allow for rich boundary layer moisture beneath the eastward-develop upper ridge. Southwesterly low-level flow across northwest Mexico into AZ will bring modest boundary-layer moisture into the southern AZ deserts as well. ...WY into western SD and Vicinity... Boundary-layer moisture is expected to modestly return in the wake of the morning cold front as the boundary stalls over western/central SD. Low-level flow is expected to become east/southeasterly during the afternoon, allowing for modest moisture return and destabilization in this post-frontal upslope flow regime. Forecast guidance suggests at least isolated thunderstorms will develop as large-scale ascent increases in response to a shortwave impulse migrating through southwesterly flow, generating modest height falls across the region. Forecast soundings indicate a deeply mixed boundary layer with inverted-v thermodynamic sub-cloud profiles amid 25 kt effective shear magnitudes. Isolated strong/severe gusts may accompany thunderstorm activity during the evening, especially if clustering/outflow consolidation occurs. ...Eastern ND into MN... Thunderstorms are expected to develop ahead of the eastward-advancing cold front by late Friday afternoon as the boundary impinges on richer boundary layer moisture. Initial capping should erode as the upper ridge shifts east toward the Great Lakes, resulting in falling heights/cooling aloft while warm advection continues in the low-levels. Even if weak capping is maintained, elevated convection is still expected. A narrow corridor of MLCAPE up to 2500 J/kg is forecast amid effective shear magnitudes around 35 kt, supporting robust updrafts and marginal supercells. Isolated hail will be possible in addition locally strong gusts. ...AZ... Modest boundary layer moisture and steep lapse rates will support around 500-1000 J/kg MLCAPE. Thunderstorms will once again develop over higher terrain and move south during the evening. Mid and upper-level flow will be a bit more northerly compared to the prior few days and fairly weak (generally less than 15 kt). Nevertheless, deep mixing and inverted-v thermodynamic profiles will support sporadic strong gusts. Given somewhat less favorable flow compared to recent days, will hold off on marginal wind probabilities at this time. ..Leitman.. 07/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1229 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF THE EASTERN CAROLINAS AND ADJACENT SOUTHEASTERN VIRGINIA...SOUTHEASTERN ARIZONA AND ADJACENT PORTIONS OF SOUTHWESTERN NEW MEXICO...AND CENTRAL MONTANA... ...SUMMARY... The risk for severe thunderstorms appears likely to remain seasonably low across much of the U.S. today through tonight. ...Synopsis... Stronger westerlies remain generally confined to the northern mid-latitudes, with one significant short wave trough and embedded low currently progressing inland of the British Columbia/Pacific Northwest coast. This perturbation is forecast to continue slowly across and east-northeast of the Canadian/northern U.S. Rockies today into early Friday, accompanied by cyclogenesis across the northern Canadian Prairies (near the northern Alberta/Saskatchewan border vicinity). While ridging to its east and south is likely to be maintained across the northern Great Plains/upper Mississippi Valley into the Southwest, models indicate that it may undergo at least some suppression, with the Southwestern mid-level high center shifting across western Arizona toward northern Baja. Farther downstream, broad mid-level troughing is forecast to continue slowly eastward across the Ohio Valley, Mid Atlantic and Northeast, with the primary embedded short wave digging southeast of the lower Great Lakes/St. Lawrence Valley, before turning across and offshore of the New England coast. Seasonably high precipitable water content will generally remain confined to portions of the northwestern Gulf coast into lower Mississippi Valley, the eastern Gulf into south Atlantic Coast states, and near the Southwestern international border area. ...Northern Rockies... Near/just ahead of the base of the mid-level short wave trough, scattered thunderstorm development is forecast to initiate off the higher terrain, and in advance of a cold front, across central Montana late this afternoon, where a hot and deeply mixed boundary layer may become characterized by modest instability. With forecast soundings suggesting 40-60 degree F temperature-dew point spreads by peak heating, a few strong downbursts are possible. Downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to the potential development of localized damaging wind gusts in consolidating outflows, as convection spreads eastward into this evening. ...Arizona... Perhaps aided by forcing associated with a perturbation progressing around the periphery of the mid-level high, thunderstorms appear likely to again initiate across the Mogollon Rim and adjacent mountains of southwestern New Mexico this afternoon. Given the position and movement of the mid-level high, northeasterly steering flow off the higher terrain toward the more strongly heated and deeply mixed lower elevations appears likely to remain focused across southeastern into adjacent portions of central Arizona, possibly including portions of the Greater Phoenix area. ...Southern Mid Atlantic... Near the southern periphery of the larger-scale mid-level troughing, a belt of 30-40 kt south to southwesterly flow in the 850-500 mb layer may enhance convective development today within a plume of seasonably high moisture content across eastern North Carolina and adjacent portions of northeastern South Carolina/southeastern Virginia. With moderate CAPE contributing to vigorous updrafts, heavy precipitation loading and downward mixing of momentum may contribute to a few strong downdrafts with potentially damaging surface gusts. ..Kerr/Halbert/Lyons.. 07/25/2024 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1229 AM CDT Thu Jul 25 2024 Valid 251200Z - 261200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS THIS AFTERNOON AND EVENING ACROSS PARTS OF THE EASTERN CAROLINAS AND ADJACENT SOUTHEASTERN VIRGINIA...SOUTHEASTERN ARIZONA AND ADJACENT PORTIONS OF SOUTHWESTERN NEW MEXICO...AND CENTRAL MONTANA... ...SUMMARY... The risk for severe thunderstorms appears likely to remain seasonably low across much of the U.S. today through tonight. ...Synopsis... Stronger westerlies remain generally confined to the northern mid-latitudes, with one significant short wave trough and embedded low currently progressing inland of the British Columbia/Pacific Northwest coast. This perturbation is forecast to continue slowly across and east-northeast of the Canadian/northern U.S. Rockies today into early Friday, accompanied by cyclogenesis across the northern Canadian Prairies (near the northern Alberta/Saskatchewan border vicinity). While ridging to its east and south is likely to be maintained across the northern Great Plains/upper Mississippi Valley into the Southwest, models indicate that it may undergo at least some suppression, with the Southwestern mid-level high center shifting across western Arizona toward northern Baja. Farther downstream, broad mid-level troughing is forecast to continue slowly eastward across the Ohio Valley, Mid Atlantic and Northeast, with the primary embedded short wave digging southeast of the lower Great Lakes/St. Lawrence Valley, before turning across and offshore of the New England coast. Seasonably high precipitable water content will generally remain confined to portions of the northwestern Gulf coast into lower Mississippi Valley, the eastern Gulf into south Atlantic Coast states, and near the Southwestern international border area. ...Northern Rockies... Near/just ahead of the base of the mid-level short wave trough, scattered thunderstorm development is forecast to initiate off the higher terrain, and in advance of a cold front, across central Montana late this afternoon, where a hot and deeply mixed boundary layer may become characterized by modest instability. With forecast soundings suggesting 40-60 degree F temperature-dew point spreads by peak heating, a few strong downbursts are possible. Downward mixing of 30-40+ kt ambient southwesterly to westerly flow in the 700-500 mb layer may contribute to the potential development of localized damaging wind gusts in consolidating outflows, as convection spreads eastward into this evening. ...Arizona... Perhaps aided by forcing associated with a perturbation progressing around the periphery of the mid-level high, thunderstorms appear likely to again initiate across the Mogollon Rim and adjacent mountains of southwestern New Mexico this afternoon. Given the position and movement of the mid-level high, northeasterly steering flow off the higher terrain toward the more strongly heated and deeply mixed lower elevations appears likely to remain focused across southeastern into adjacent portions of central Arizona, possibly including portions of the Greater Phoenix area. ...Southern Mid Atlantic... Near the southern periphery of the larger-scale mid-level troughing, a belt of 30-40 kt south to southwesterly flow in the 850-500 mb layer may enhance convective development today within a plume of seasonably high moisture content across eastern North Carolina and adjacent portions of northeastern South Carolina/southeastern Virginia. With moderate CAPE contributing to vigorous updrafts, heavy precipitation loading and downward mixing of momentum may contribute to a few strong downdrafts with potentially damaging surface gusts. ..Kerr/Halbert/Lyons.. 07/25/2024 Read more