Aggregator

Issued at 1500 UTC TUE AUG 05 2025 402 WTPZ23 KNHC 051438 TCMEP3 TROPICAL STORM HENRIETTE FORECAST/ADVISORY NUMBER 6 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082025 1500 UTC TUE AUG 05 2025 TROPICAL STORM CENTER LOCATED NEAR 16.4N 124.3W AT 05/1500Z POSITION ACCURATE WITHIN 30 NM PRESENT MOVEMENT TOWARD THE WEST-NORTHWEST OR 290 DEGREES AT 13 KT ESTIMATED MINIMUM CENTRAL PRESSURE 1003 MB MAX SUSTAINED WINDS 45 KT WITH GUSTS TO 55 KT. 34 KT....... 60NE 50SE 50SW 60NW. 4 M SEAS.... 90NE 30SE 45SW 75NW. WINDS AND SEAS VARY GREATLY IN EACH QUADRANT. RADII IN NAUTICAL MILES ARE THE LARGEST RADII EXPECTED ANYWHERE IN THAT QUADRANT. REPEAT...CENTER LOCATED NEAR 16.4N 124.3W AT 05/1500Z AT 05/1200Z CENTER WAS LOCATED NEAR 16.2N 123.7W FORECAST VALID 06/0000Z 16.9N 126.3W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 70NE 50SE 50SW 60NW. FORECAST VALID 06/1200Z 17.5N 129.1W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 65NE 50SE 50SW 60NW. FORECAST VALID 07/0000Z 18.0N 132.0W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 70NE 50SE 50SW 60NW. FORECAST VALID 07/1200Z 18.4N 134.9W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 40SE 40SW 60NW. FORECAST VALID 08/0000Z 18.8N 137.9W MAX WIND 45 KT...GUSTS 55 KT. 34 KT... 60NE 40SE 40SW 60NW. FORECAST VALID 08/1200Z 19.3N 140.8W MAX WIND 40 KT...GUSTS 50 KT. 34 KT... 60NE 40SE 30SW 60NW. EXTENDED OUTLOOK. NOTE...ERRORS FOR TRACK HAVE AVERAGED NEAR 100 NM ON DAY 4 AND 125 NM ON DAY 5...AND FOR INTENSITY NEAR 15 KT EACH DAY OUTLOOK VALID 09/1200Z 21.0N 146.1W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 60NE 40SE 30SW 50NW. OUTLOOK VALID 10/1200Z 23.4N 150.7W MAX WIND 35 KT...GUSTS 45 KT. 34 KT... 60NE 40SE 30SW 50NW. REQUEST FOR 3 HOURLY SHIP REPORTS WITHIN 300 MILES OF 16.4N 124.3W NEXT ADVISORY AT 05/2100Z $$ FORECASTER ROBERTS

Issued at 500 AM HST Tue Aug 05 2025 403 WTPZ33 KNHC 051438 TCPEP3 BULLETIN Tropical Storm Henriette Advisory Number 6 NWS National Hurricane Center Miami FL EP082025 500 AM HST Tue Aug 05 2025 ...HENRIETTE MOVING OVER THE CENTRAL EAST PACIFIC... ...LITTLE CHANGE IN STRENGTH EXPECTED... SUMMARY OF 500 AM HST...1500 UTC...INFORMATION ---------------------------------------------- LOCATION...16.4N 124.3W ABOUT 1035 MI...1670 KM WSW OF THE SOUTHERN TIP OF BAJA CALIFORNIA MAXIMUM SUSTAINED WINDS...50 MPH...85 KM/H PRESENT MOVEMENT...WNW OR 290 DEGREES AT 15 MPH...24 KM/H MINIMUM CENTRAL PRESSURE...1003 MB...29.62 INCHES WATCHES AND WARNINGS -------------------- There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 500 AM HST (1500 UTC), the center of Tropical Storm Henriette was located near latitude 16.4 North, longitude 124.3 West. Henriette is moving toward the west-northwest near 15 mph (24 km/h), and this general motion is expected to continue during the next few days. Maximum sustained winds are near 50 mph (85 km/h) with higher gusts. Little change in strength is expected during the next few days followed by gradual weakening toward the end of the week while the cyclone passes to the east-northeast of the Hawaiian Islands. Tropical-storm-force winds extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 1003 mb (29.62 inches). HAZARDS AFFECTING LAND ---------------------- None. NEXT ADVISORY ------------- Next complete advisory at 1100 AM HST. $$ Forecaster Roberts

...HENRIETTE MOVING OVER THE CENTRAL EAST PACIFIC... ...LITTLE CHANGE IN STRENGTH EXPECTED... As of 5:00 AM HST Tue Aug 05 the center of Henriette was located near 16.4, -124.3 with movement WNW at 15 mph. The minimum central pressure was 1003 mb with maximum sustained winds of about 50 mph.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ...Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ..Mosier/Bentley.. 08/05/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ...Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ..Mosier/Bentley.. 08/05/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ...Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ..Mosier/Bentley.. 08/05/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ...Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ..Mosier/Bentley.. 08/05/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0742 AM CDT Tue Aug 05 2025 Valid 051300Z - 061200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS MUCH OF NORTH AND SOUTH DAKOTA... ...SUMMARY... Thunderstorms associated with a threat for severe gusts and large hail will be possible across parts of the Dakotas today into this evening. ...Northern Plains... Warm-air advection showers and thunderstorms are ongoing this morning across the western Dakotas, where the western edge of the low-level jet overlaps the eastern edge of the steep mid-level lapse rates. These storms will likely continue northeastward this morning, perhaps even expanding in coverage, as the low-level jet persists and large-scale ascent attendant to an approaching shortwave trough strengthens. Occasionally strong updrafts could produce hail and a damaging gust or two. Cloud cover and outflow associated with these storms could result in an effective warm front extending from a weak low over western SD eastward across central and eastern SD. The exact location and sharpness of this front remain uncertain. Given that the shortwave trough will likely remain well west of the region, low-level convergence near this boundary as well as the surface low should both be areas where convective initiation is most likely this afternoon. Ample buoyancy and vertical shear will be in place for supercells with the initial development, with large hail and damaging gusts as the primary risks. Stronger low to mid-level flow may be in place across eastern SD, contributing to greater low-level shear and relatively higher tornado potential. Primary concern across eastern SD is whether or not the warmer low to mid-level temperatures inhibit the development of mature updrafts. One other scenario that seems plausible is for storms on southern periphery the ongoing cluster to become increasingly surface based as they move eastward/northeastward with time. Given current trends and recent guidance, this would most likely occur along the eastern ND/SD border after 20Z. As previously mentioned, hail is possible within this cluster throughout the day, but the transition to a more surface-based character could introduce the threat for stronger gusts as well. A strengthening low-level jet coupled with persistent mid-level westerlies support the potential for upscale growth in a east-southeastward progressing MCS. Damaging gusts will be possible with this MCS, particularly over SD, but increasing low-level stability should result in a gradually diminishing severe potential with eastward/southeastward extend into northeast NE, northwest IA, and southwest MN. ..Mosier/Bentley.. 08/05/2025 Read more

681
ABPZ20 KNHC 051123
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 AM PDT Tue Aug 5 2025

For the eastern and central North Pacific east of 180 longitude:

Active Systems:
The National Hurricane Center is issuing advisories on Tropical
Storm Henriette, located well southwest of the Baja California
Peninsula. Henriette is expected to move into the Central Pacific
basin Thursday night or Friday morning.

South of Southern Mexico:
An area of low pressure located a couple hundred miles offshore of
the coast of Central America is producing a large area of
disorganized showers and thunderstorms. Environmental conditions
appear conducive for development of this system, and a tropical
depression is likely to form during the next couple of days while
it moves west-northwestward around 15 mph.
* Formation chance through 48 hours...medium...60 percent.
* Formation chance through 7 days...high...90 percent.

$$
Forecaster Roberts

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0358 AM CDT Tue Aug 05 2025 Valid 081200Z - 131200Z ...DISCUSSION... ...Friday/Day 4 to Sunday/Day 6... On Friday, a mid-level trough and an associated speed max is forecast to move into the northern Plains. At the surface, a moist airmass will be in place over much of the northern Plains, where surface dewpoints are likely to be in the lower to mid 70s F. As surface temperatures warm during the day, moderate to strong instability is expected to develop. Along the northwestern edge of this unstable airmass, thunderstorms should form in parts of central and eastern North Dakota. Convective coverage is forecast to expand southward into South Dakota during the evening. Moderate to strong deep-layer shear associated with the speed max will be favorable for a severe threat during the afternoon and evening. Supercells with large hail, severe wind gusts and a tornado threat will be possible. On Saturday, the mid-level trough and associated cold front are forecast to move eastward into the upper Mississippi and mid Missouri Valleys. Thunderstorms are forecast to be ongoing along and near the front during the morning, with additional thunderstorm development taking place further southeast in the afternoon. Moderate instability and deep-layer shear is forecast across much of the region, suggesting that a severe threat will again be possible. There is some uncertainty as to how much the airmass will be negatively affected by the morning convection. Also, model forecasts suggest that the greatest convective potential will be during the overnight period on Saturday. For this reason, will not add a threat area for Saturday at this time. On Sunday, a mid-level trough is forecast to move across the north-central U.S., being positioned from the northern Plains to the central Rockies by afternoon. A moderately unstable airmass is forecast further to the east, from the upper Mississippi Valley southward into the mid Missouri Valley. An isolated severe threat will be possible Sunday afternoon along and near the instability axis. However, the mid-level trough is forecast to remain well to the west of the instability axis, which should limit large-scale ascent over the unstable airmass, helping to keep any severe threat isolated. ...Monday/Day 7 and Tuesday/Day 8... A low-amplitude mid-level trough is forecast to move into the upper Mississippi Valley on Monday, and into the western Great Lakes on Tuesday. Further southwest, a mid-level low is forecast across the central Plains. Thunderstorms will be possible on Monday and Tuesday afternoon, along the northern edge of a moist airmass from the central Plains northeastward to the Great Lakes. Model forecasts suggest that deep-layer shear will be relatively weak. Although convective coverage and any associated severe threat will likely remain isolated, a few marginally severe storms could occur in areas that heat up the most. Read more

MD 1889 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR FAR SOUTHEAST MONTANA...FAR NORTHEAST WYOMING AND WESTERN SOUTH DAKOTA.
Mesoscale Discussion 1889 NWS Storm Prediction Center Norman OK 0258 AM CDT Tue Aug 05 2025 Areas affected...far southeast Montana...far northeast Wyoming and western South Dakota. Concerning...Severe potential...Watch unlikely Valid 050758Z - 050930Z Probability of Watch Issuance...20 percent SUMMARY...Isolated large hail is possible early this morning across portions of southeast Montana, northeast Wyoming, and western South Dakota. DISCUSSION...The low-level jet has strengthened significantly over the past hour across western South Dakota (now approaching 40 knots on the KUDX VWP). As a result, elevated thunderstorms have increased in coverage across western South Dakota and far southeast Montana. An environment featuring 30 to 40 knots of deep layer shear, 2000 to 2500 J/kg MUCAPE, and support from the low-level jet may result in a few elevated supercells capable of primarily large hail early this morning. In addition, a mature MCS has developed across southeast Montana. As this MCS advances east, at least some severe wind potential could exist if a more consolidated/faster moving segment can emerge from this MCS. At this time, the stronger storm in Powder River, Montana would likely have the greatest potential for this solution as it moves east-southeast along the instability gradient early this morning. Given the isolated nature of the threat, a severe thunderstorm watch is unlikely. ..Bentley/Mosier.. 08/05/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...BYZ... LAT...LON 44850523 45120566 45320572 45520561 45690440 45650320 45280185 44810143 44080122 43310115 43000191 43020270 43150354 44010408 44590467 44850523 MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

5-Day Uncertainty Track last updated Tue, 05 Aug 2025 08:44:54 GMT


Wind Speed Probabilities last updated Tue, 05 Aug 2025 08:44:54 GMT

Issued at 1100 PM HST Mon Aug 04 2025 000 WTPZ43 KNHC 050842 TCDEP3 Tropical Storm Henriette Discussion Number 5 NWS National Hurricane Center Miami FL EP082025 1100 PM HST Mon Aug 04 2025 The satellite presentation of Henriette has degraded some since the previous advisory, with cloud tops warming and the curved band structure becoming more fragmented. The latest subjective Dvorak intensity estimates from TAFB and SAB are both 3.0/45 kt, while objective estimates from UW-CIMSS have ranged from 37 to 46 kt during the past several hours. Meanwhile, a timely 05/0545Z Metop-C ASCAT pass showed several 40-45 kt wind barbs, assisting with determining the initial intensity as well as the extent of the tropical-storm-force wind radii. The initial intensity for this advisory has been held at 45 kt. The cyclone is moving west-northwest, or 290 degrees, at 13 knots. This general motion is expected to continue during the next day or so, as Henriette moves along the southern edge of a subtropical ridge to the north. Between 36 and 72 hours, a slight turn toward the west is forecast as the ridge strengthens north of the cyclone. Beyond 72 hours, a turn back toward the west-northwest or northwest is anticipated as an amplifying longwave trough northwest of Hawaii erodes the western extent of the subtropical ridge steering the cyclone. The official track forecast closely follows a blend of the latest HCCA/TVCE/FSSE consensus guidance, and is very close to the track from the previous advisory. Henriette appears to have a brief window for further intensification over the next 12 to 18 hours, as sea surface temperatures hover between 26 and 26.5C, mid-level moisture remains sufficient, and vertical wind shear stays light. Little change in strength is expected then through 36 hours as the cyclone moves over slightly cooler water but close to the 26C isotherm, while shear remains light and the mid-levels remain moist. Beyond 36 hours, the cyclone is expected to move over progressively cooler waters, with mid-level moisture decreasing, and these conditions should lead to gradual weakening. The official forecast maintains Henriette as a tropical cyclone through 120 hours, however, it would not be surprising if it transitions into a post-tropical low prior to day 5. The intensity forecast is most closely aligned with the FSSE, which is near the middle of the intensity guidance envelope. FORECAST POSITIONS AND MAX WINDS INIT 05/0900Z 15.9N 123.1W 45 KT 50 MPH 12H 05/1800Z 16.5N 125.0W 50 KT 60 MPH 24H 06/0600Z 17.2N 127.7W 50 KT 60 MPH 36H 06/1800Z 17.8N 130.6W 50 KT 60 MPH 48H 07/0600Z 18.2N 133.5W 45 KT 50 MPH 60H 07/1800Z 18.5N 136.5W 45 KT 50 MPH 72H 08/0600Z 19.0N 139.6W 40 KT 45 MPH 96H 09/0600Z 20.3N 144.9W 35 KT 40 MPH 120H 10/0600Z 22.3N 149.8W 35 KT 40 MPH $$ Forecaster Jelsema (CPHC)

Issued at 0900 UTC TUE AUG 05 2025 000 FOPZ13 KNHC 050842 PWSEP3 TROPICAL STORM HENRIETTE WIND SPEED PROBABILITIES NUMBER 5 NWS NATIONAL HURRICANE CENTER MIAMI FL EP082025 0900 UTC TUE AUG 05 2025 AT 0900Z THE CENTER OF TROPICAL STORM HENRIETTE WAS LOCATED NEAR LATITUDE 15.9 NORTH...LONGITUDE 123.1 WEST WITH MAXIMUM SUSTAINED WINDS NEAR 45 KTS...50 MPH...85 KM/H. Z INDICATES COORDINATED UNIVERSAL TIME (GREENWICH) PACIFIC DAYLIGHT TIME (PDT)...SUBTRACT 7 HOURS FROM Z TIME HAWAIIAN STANDARD TIME (HST)...SUBTRACT 10 HOURS FROM Z TIME WIND SPEED PROBABILITY TABLE FOR SPECIFIC LOCATIONS CHANCES OF SUSTAINED (1-MINUTE AVERAGE) WIND SPEEDS OF AT LEAST ...34 KT (39 MPH... 63 KM/H)... ...50 KT (58 MPH... 93 KM/H)... ...64 KT (74 MPH...119 KM/H)... FOR LOCATIONS AND TIME PERIODS DURING THE NEXT 5 DAYS PROBABILITIES FOR LOCATIONS ARE GIVEN AS OP(CP) WHERE OP IS THE PROBABILITY OF THE EVENT BEGINNING DURING AN INDIVIDUAL TIME PERIOD (ONSET PROBABILITY) (CP) IS THE PROBABILITY OF THE EVENT OCCURRING BETWEEN 06Z TUE AND THE FORECAST HOUR (CUMULATIVE PROBABILITY) PROBABILITIES ARE GIVEN IN PERCENT X INDICATES PROBABILITIES LESS THAN 1 PERCENT PROBABILITIES FOR 34 KT AND 50 KT ARE SHOWN AT A GIVEN LOCATION WHEN THE 5-DAY CUMULATIVE PROBABILITY IS AT LEAST 3 PERCENT. PROBABILITIES FOR 34...50...64 KT SHOWN WHEN THE 5-DAY 64-KT CUMULATIVE PROBABILITY IS AT LEAST 1 PERCENT. - - - - WIND SPEED PROBABILITIES FOR SELECTED LOCATIONS - - - - FROM FROM FROM FROM FROM FROM FROM TIME 06Z TUE 18Z TUE 06Z WED 18Z WED 06Z THU 06Z FRI 06Z SAT PERIODS TO TO TO TO TO TO TO 18Z TUE 06Z WED 18Z WED 06Z THU 06Z FRI 06Z SAT 06Z SUN FORECAST HOUR (12) (24) (36) (48) (72) (96) (120) - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - LOCATION KT 15N 125W 34 16 1(17) X(17) X(17) X(17) X(17) X(17) 20N 125W 34 1 2( 3) 1( 4) X( 4) X( 4) X( 4) X( 4) 15N 130W 34 X 2( 2) 3( 5) 1( 6) X( 6) X( 6) X( 6) 20N 130W 34 X 2( 2) 8(10) 1(11) X(11) X(11) X(11) 15N 135W 34 X X( X) X( X) 2( 2) 1( 3) X( 3) X( 3) 20N 135W 34 X X( X) 1( 1) 8( 9) 12(21) X(21) X(21) 20N 135W 50 X X( X) X( X) X( X) 3( 3) X( 3) X( 3) 20N 140W 34 X X( X) X( X) X( X) 19(19) 6(25) X(25) 20N 140W 50 X X( X) X( X) X( X) 4( 4) 1( 5) X( 5) 20N 145W 34 X X( X) X( X) X( X) X( X) 14(14) 2(16) 20N 145W 50 X X( X) X( X) X( X) X( X) 2( 2) 1( 3) 20N 150W 34 X X( X) X( X) X( X) X( X) X( X) 4( 4) 25N 150W 34 X X( X) X( X) X( X) X( X) X( X) 3( 3) $$ FORECASTER JELSEMA (CPHC)