Aggregator

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0112 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z The Elevated area was expanded across portions of the Great Basin and into the northern Rockies as dry/breezy conditions are becoming more likely with the breakdown of the upper-level ridge. Latest high-resolution guidance has higher probabilities of elevated to locally critical winds/RH along/ahead of a cold front with above normal temperatures across this area. The IsoDryT area was modified, but uncertainty regarding coverage of thunderstorms has increased. Moisture and instability will be limited, but enough instability and forcing for ascent may be sufficient to produce isolated high-based showers and thunderstorms. Chances of convection begin early in the morning and do persist overnight. If thunderstorms fail to develop, high-based showers mixed with building cumulus are likely. Additionally, any active large wildfires in/near the IsoDryT area have increased chances of deep pyroconvection given the favorable sounding profiles. ..Nauslar.. 08/19/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Aug 19 2025/ ...Synopsis... A strong upper ridge is forecast to build over the Southwest as weak troughing continues over parts of the Northwest. A shortwave trough, embedded within the broader northern trough, will move eastward into the northern Rockies Wednesday. Increased southwesterly flow aloft will help monsoon moisture (PWATs 0.6-0.8 inches) advect northward over NV and western UT. A surface cold front associated with the upper trough will stall over the western Great Basin serving as a focus for thunderstorm development through the afternoon. Isolated and likely dry storms are expected over parts of NV and UT. A few storms may possibly continue overnight in eastern Idaho and northwest Wyoming. ...ID... In addition to the isolated risk for thunderstorms, the strong flow aloft and cold front will promote gusty west/southwest winds through portions of the Snake River Plane and northern Great Basin Wednesday. Afternoon gusts of 15-20 mph are possible ahead of the cold front. Very warm temperatures are expected under the ridge with afternoon humidity also expected to be low. With winds and low humidity overlapping with dry fuels, elevated fire-weather conditions are possible. Some dry and breezy conditions may also develop farther south over the Great Basin. However, increasing monsoon moisture along the front and more sporadic surface winds suggest lower confidence for sustained elevated fire-weather conditions. Localized dry and breezy could still occur, especially around any active fires given the very warm and dry conditions. ...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 0112 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z The Elevated area was expanded across portions of the Great Basin and into the northern Rockies as dry/breezy conditions are becoming more likely with the breakdown of the upper-level ridge. Latest high-resolution guidance has higher probabilities of elevated to locally critical winds/RH along/ahead of a cold front with above normal temperatures across this area. The IsoDryT area was modified, but uncertainty regarding coverage of thunderstorms has increased. Moisture and instability will be limited, but enough instability and forcing for ascent may be sufficient to produce isolated high-based showers and thunderstorms. Chances of convection begin early in the morning and do persist overnight. If thunderstorms fail to develop, high-based showers mixed with building cumulus are likely. Additionally, any active large wildfires in/near the IsoDryT area have increased chances of deep pyroconvection given the favorable sounding profiles. ..Nauslar.. 08/19/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Aug 19 2025/ ...Synopsis... A strong upper ridge is forecast to build over the Southwest as weak troughing continues over parts of the Northwest. A shortwave trough, embedded within the broader northern trough, will move eastward into the northern Rockies Wednesday. Increased southwesterly flow aloft will help monsoon moisture (PWATs 0.6-0.8 inches) advect northward over NV and western UT. A surface cold front associated with the upper trough will stall over the western Great Basin serving as a focus for thunderstorm development through the afternoon. Isolated and likely dry storms are expected over parts of NV and UT. A few storms may possibly continue overnight in eastern Idaho and northwest Wyoming. ...ID... In addition to the isolated risk for thunderstorms, the strong flow aloft and cold front will promote gusty west/southwest winds through portions of the Snake River Plane and northern Great Basin Wednesday. Afternoon gusts of 15-20 mph are possible ahead of the cold front. Very warm temperatures are expected under the ridge with afternoon humidity also expected to be low. With winds and low humidity overlapping with dry fuels, elevated fire-weather conditions are possible. Some dry and breezy conditions may also develop farther south over the Great Basin. However, increasing monsoon moisture along the front and more sporadic surface winds suggest lower confidence for sustained elevated fire-weather conditions. Localized dry and breezy could still occur, especially around any active fires given the very warm and dry conditions. ...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 0112 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z The Elevated area was expanded across portions of the Great Basin and into the northern Rockies as dry/breezy conditions are becoming more likely with the breakdown of the upper-level ridge. Latest high-resolution guidance has higher probabilities of elevated to locally critical winds/RH along/ahead of a cold front with above normal temperatures across this area. The IsoDryT area was modified, but uncertainty regarding coverage of thunderstorms has increased. Moisture and instability will be limited, but enough instability and forcing for ascent may be sufficient to produce isolated high-based showers and thunderstorms. Chances of convection begin early in the morning and do persist overnight. If thunderstorms fail to develop, high-based showers mixed with building cumulus are likely. Additionally, any active large wildfires in/near the IsoDryT area have increased chances of deep pyroconvection given the favorable sounding profiles. ..Nauslar.. 08/19/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Aug 19 2025/ ...Synopsis... A strong upper ridge is forecast to build over the Southwest as weak troughing continues over parts of the Northwest. A shortwave trough, embedded within the broader northern trough, will move eastward into the northern Rockies Wednesday. Increased southwesterly flow aloft will help monsoon moisture (PWATs 0.6-0.8 inches) advect northward over NV and western UT. A surface cold front associated with the upper trough will stall over the western Great Basin serving as a focus for thunderstorm development through the afternoon. Isolated and likely dry storms are expected over parts of NV and UT. A few storms may possibly continue overnight in eastern Idaho and northwest Wyoming. ...ID... In addition to the isolated risk for thunderstorms, the strong flow aloft and cold front will promote gusty west/southwest winds through portions of the Snake River Plane and northern Great Basin Wednesday. Afternoon gusts of 15-20 mph are possible ahead of the cold front. Very warm temperatures are expected under the ridge with afternoon humidity also expected to be low. With winds and low humidity overlapping with dry fuels, elevated fire-weather conditions are possible. Some dry and breezy conditions may also develop farther south over the Great Basin. However, increasing monsoon moisture along the front and more sporadic surface winds suggest lower confidence for sustained elevated fire-weather conditions. Localized dry and breezy could still occur, especially around any active fires given the very warm and dry conditions. ...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 0112 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z The Elevated area was expanded across portions of the Great Basin and into the northern Rockies as dry/breezy conditions are becoming more likely with the breakdown of the upper-level ridge. Latest high-resolution guidance has higher probabilities of elevated to locally critical winds/RH along/ahead of a cold front with above normal temperatures across this area. The IsoDryT area was modified, but uncertainty regarding coverage of thunderstorms has increased. Moisture and instability will be limited, but enough instability and forcing for ascent may be sufficient to produce isolated high-based showers and thunderstorms. Chances of convection begin early in the morning and do persist overnight. If thunderstorms fail to develop, high-based showers mixed with building cumulus are likely. Additionally, any active large wildfires in/near the IsoDryT area have increased chances of deep pyroconvection given the favorable sounding profiles. ..Nauslar.. 08/19/2025 .PREV DISCUSSION... /ISSUED 0159 AM CDT Tue Aug 19 2025/ ...Synopsis... A strong upper ridge is forecast to build over the Southwest as weak troughing continues over parts of the Northwest. A shortwave trough, embedded within the broader northern trough, will move eastward into the northern Rockies Wednesday. Increased southwesterly flow aloft will help monsoon moisture (PWATs 0.6-0.8 inches) advect northward over NV and western UT. A surface cold front associated with the upper trough will stall over the western Great Basin serving as a focus for thunderstorm development through the afternoon. Isolated and likely dry storms are expected over parts of NV and UT. A few storms may possibly continue overnight in eastern Idaho and northwest Wyoming. ...ID... In addition to the isolated risk for thunderstorms, the strong flow aloft and cold front will promote gusty west/southwest winds through portions of the Snake River Plane and northern Great Basin Wednesday. Afternoon gusts of 15-20 mph are possible ahead of the cold front. Very warm temperatures are expected under the ridge with afternoon humidity also expected to be low. With winds and low humidity overlapping with dry fuels, elevated fire-weather conditions are possible. Some dry and breezy conditions may also develop farther south over the Great Basin. However, increasing monsoon moisture along the front and more sporadic surface winds suggest lower confidence for sustained elevated fire-weather conditions. Localized dry and breezy could still occur, especially around any active fires given the very warm and dry conditions. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

211
ABNT20 KNHC 191738
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
200 PM EDT Tue Aug 19 2025

For the North Atlantic...Caribbean Sea and the Gulf of America:

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Erin, located a couple of hundred miles to the northeast of the
Southeast Bahamas.

Near the Leeward Islands in the Tropical Atlantic:
A tropical wave located over the central tropical Atlantic continues
to produce a broad area of disorganized showers and thunderstorms.
Environmental conditions appear conducive for gradual development of
this system, and a tropical depression could form toward the end of
the week or this weekend. This system should move westward to
west-northwestward at about 20 mph and approach the vicinity of the
northern Leeward Islands on Friday.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...medium...60 percent.

Eastern Tropical Atlantic (AL99):
A tropical wave located about a hundred miles to the south of the
Cabo Verde Islands continues to produce disorganized showers and
thunderstorms. Environmental conditions appear marginally favorable
for additional development over the next couple of days as the
system moves westward at around 15 mph. Towards the end of this
week, this system could encounter a less favorable environment,
limiting its development chances after that time.
* Formation chance through 48 hours...low...30 percent.
* Formation chance through 7 days...low...30 percent.

$$
Forecaster Bucci

000
ABPZ20 KNHC 191737
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Aug 19 2025

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

Tropical cyclone formation is not expected during the next 7 days.

$$
Forecaster Bucci

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1202 PM CDT Tue Aug 19 2025 Valid 201200Z - 211200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS FAR NORTHEAST MONTANA AND PARTS OF NORTHERN NORTH DAKOTA... ...SUMMARY... Isolated severe thunderstorms are possible on Wednesday evening across northern North Dakota and far northeast Montana. ...Northeast MT into northern ND... A strong upper anticyclone will be centered over the Four Corners, with attendant upper riding extending north/northeast into the northern Plains. A shortwave upper trough is forecast to develop east across the Canadian Rockies, and eventually into Saskatchewan late in the period. This will result in height falls across the northern Rockies into the northern Plains generally after 00z. As this occurs, mid/upper westerly flow will increase. Modestly deepening low pressure over eastern MT likely will result in increasing southerly low-level flow ahead of a southeastward-advancing cold front moving across the region from late afternoon into the nighttime hours. A narrow corridor of rich boundary layer moisture will exist across western ND ahead of the front. Steep lapse rates will support 1500-3000 J/kg MLCAPE values. However, capping will likely suppress diurnal convection. As strong ascent accompanies the approach of the surface front and upper trough during the evening/nighttime hours, isolated convection is possible. A marginal wind/hail risk could accompany any stronger sustained storms near the advancing cold front. ..Leitman.. 08/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Aug 19 2025 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY TO THE SOUTHERN/CENTRAL PLAINS...AND OVER PORTIONS OF WESTERN/NORTHERN MONTANA... ...SUMMARY... Scattered thunderstorms capable of producing occasional damaging winds will be possible across parts of the south-central Plains and Ozarks to the Ohio Valley this afternoon and evening. Isolated severe thunderstorms may also occur this evening across parts of western and northern Montana. ...Ohio Valley to the Central/Southern Plains... Upper ridging will remain prominent today across the Southwest and southern/central Rockies, as a weak mid/upper-level trough moves east-southeastward across the Great Lakes and OH Valley regions. At the surface, a weak cold front is forecast to advance east-southeastward across parts of the OH Valley and mid MS Valley today, and more slowly southward over portions of the central/southern Plains while weakening. This boundary should aid in at least scattered thunderstorm development through the afternoon as diurnal heating of a moist airmass along/south of the front occurs. While deep-layer flow and related shear are expected to remain generally weak, moderate to strong instability and the steepening of low-level lapse rates may support occasional strong to damaging winds with water-loaded downdrafts within the stronger cores. Only minor adjustments have been made to the broad Marginal Risk based on latest observational and short-term guidance trends. ...Northern Rockies/High Plains... An embedded mid-level shortwave trough will advance northeastward this evening and overnight across parts of the northern Rockies and adjacent High Plains on the western to northern periphery of prominent upper ridging over the Southwest. Isolated to perhaps widely scattered thunderstorms should develop through the evening hours across parts of western MT and vicinity as large-scale ascent associated with the shortwave trough overspreads the northern Rockies. Instability is forecast to remain rather limited, but steepened lapse rates aloft and a well-mixed boundary layer could still aid in some convective downdraft enhancement, with isolated strong to severe gusts possible as convection spreads northeastward towards the international border. ...Coastal Texas... A weak mid-level perturbation with ongoing thunderstorms along parts of the middle TX Coast should continue south-southwestward this afternoon and evening. Low/mid-level flow should remain modest, which will generally limit thunderstorm organization. Still, some clustering could support isolated strong/gusty winds in the presence of increasing instability this afternoon across parts of south-central TX and the lower TX Coast. Confidence in severe-caliber gusts remains too low to include any severe probabilities at this time. ..Gleason/Wendt.. 08/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Aug 19 2025 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY TO THE SOUTHERN/CENTRAL PLAINS...AND OVER PORTIONS OF WESTERN/NORTHERN MONTANA... ...SUMMARY... Scattered thunderstorms capable of producing occasional damaging winds will be possible across parts of the south-central Plains and Ozarks to the Ohio Valley this afternoon and evening. Isolated severe thunderstorms may also occur this evening across parts of western and northern Montana. ...Ohio Valley to the Central/Southern Plains... Upper ridging will remain prominent today across the Southwest and southern/central Rockies, as a weak mid/upper-level trough moves east-southeastward across the Great Lakes and OH Valley regions. At the surface, a weak cold front is forecast to advance east-southeastward across parts of the OH Valley and mid MS Valley today, and more slowly southward over portions of the central/southern Plains while weakening. This boundary should aid in at least scattered thunderstorm development through the afternoon as diurnal heating of a moist airmass along/south of the front occurs. While deep-layer flow and related shear are expected to remain generally weak, moderate to strong instability and the steepening of low-level lapse rates may support occasional strong to damaging winds with water-loaded downdrafts within the stronger cores. Only minor adjustments have been made to the broad Marginal Risk based on latest observational and short-term guidance trends. ...Northern Rockies/High Plains... An embedded mid-level shortwave trough will advance northeastward this evening and overnight across parts of the northern Rockies and adjacent High Plains on the western to northern periphery of prominent upper ridging over the Southwest. Isolated to perhaps widely scattered thunderstorms should develop through the evening hours across parts of western MT and vicinity as large-scale ascent associated with the shortwave trough overspreads the northern Rockies. Instability is forecast to remain rather limited, but steepened lapse rates aloft and a well-mixed boundary layer could still aid in some convective downdraft enhancement, with isolated strong to severe gusts possible as convection spreads northeastward towards the international border. ...Coastal Texas... A weak mid-level perturbation with ongoing thunderstorms along parts of the middle TX Coast should continue south-southwestward this afternoon and evening. Low/mid-level flow should remain modest, which will generally limit thunderstorm organization. Still, some clustering could support isolated strong/gusty winds in the presence of increasing instability this afternoon across parts of south-central TX and the lower TX Coast. Confidence in severe-caliber gusts remains too low to include any severe probabilities at this time. ..Gleason/Wendt.. 08/19/2025 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CDT Tue Aug 19 2025 Valid 191630Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE OHIO VALLEY TO THE SOUTHERN/CENTRAL PLAINS...AND OVER PORTIONS OF WESTERN/NORTHERN MONTANA... ...SUMMARY... Scattered thunderstorms capable of producing occasional damaging winds will be possible across parts of the south-central Plains and Ozarks to the Ohio Valley this afternoon and evening. Isolated severe thunderstorms may also occur this evening across parts of western and northern Montana. ...Ohio Valley to the Central/Southern Plains... Upper ridging will remain prominent today across the Southwest and southern/central Rockies, as a weak mid/upper-level trough moves east-southeastward across the Great Lakes and OH Valley regions. At the surface, a weak cold front is forecast to advance east-southeastward across parts of the OH Valley and mid MS Valley today, and more slowly southward over portions of the central/southern Plains while weakening. This boundary should aid in at least scattered thunderstorm development through the afternoon as diurnal heating of a moist airmass along/south of the front occurs. While deep-layer flow and related shear are expected to remain generally weak, moderate to strong instability and the steepening of low-level lapse rates may support occasional strong to damaging winds with water-loaded downdrafts within the stronger cores. Only minor adjustments have been made to the broad Marginal Risk based on latest observational and short-term guidance trends. ...Northern Rockies/High Plains... An embedded mid-level shortwave trough will advance northeastward this evening and overnight across parts of the northern Rockies and adjacent High Plains on the western to northern periphery of prominent upper ridging over the Southwest. Isolated to perhaps widely scattered thunderstorms should develop through the evening hours across parts of western MT and vicinity as large-scale ascent associated with the shortwave trough overspreads the northern Rockies. Instability is forecast to remain rather limited, but steepened lapse rates aloft and a well-mixed boundary layer could still aid in some convective downdraft enhancement, with isolated strong to severe gusts possible as convection spreads northeastward towards the international border. ...Coastal Texas... A weak mid-level perturbation with ongoing thunderstorms along parts of the middle TX Coast should continue south-southwestward this afternoon and evening. Low/mid-level flow should remain modest, which will generally limit thunderstorm organization. Still, some clustering could support isolated strong/gusty winds in the presence of increasing instability this afternoon across parts of south-central TX and the lower TX Coast. Confidence in severe-caliber gusts remains too low to include any severe probabilities at this time. ..Gleason/Wendt.. 08/19/2025 Read more