Aggregator

...FLOSSIE CONTINUES TO STRENGTHEN... ...OUTER RAINBANDS OF FLOSSIE BRUSHING THE COAST OF SOUTHWESTERN MEXICO... As of 12:00 PM CST Tue Jul 01 the center of Flossie was located near 17.5, -106.5 with movement NW at 10 mph. The minimum central pressure was 966 mb with maximum sustained winds of about 110 mph.

Issued at 1200 PM CST Tue Jul 01 2025 944 WTPZ31 KNHC 011744 TCPEP1 BULLETIN Hurricane Flossie Intermediate Advisory Number 10A NWS National Hurricane Center Miami FL EP062025 1200 PM CST Tue Jul 01 2025 ...FLOSSIE CONTINUES TO STRENGTHEN... ...OUTER RAINBANDS OF FLOSSIE BRUSHING THE COAST OF SOUTHWESTERN MEXICO... SUMMARY OF 1200 PM CST...1800 UTC...INFORMATION ----------------------------------------------- LOCATION...17.5N 106.5W ABOUT 180 MI...285 KM SW OF MANZANILLO MEXICO ABOUT 430 MI...700 KM SSE OF CABO SAN LUCAS MEXICO MAXIMUM SUSTAINED WINDS...110 MPH...175 KM/H PRESENT MOVEMENT...NW OR 305 DEGREES AT 10 MPH...17 KM/H MINIMUM CENTRAL PRESSURE...966 MB...28.53 INCHES WATCHES AND WARNINGS -------------------- CHANGES WITH THIS ADVISORY: None. SUMMARY OF WATCHES AND WARNINGS IN EFFECT: A Tropical Storm Warning is in effect for... * Punta San Telmo to Playa Perula A Tropical Storm Watch is in effect for... * East of Punta San Telmo to Zihuatanejo * North of Playa Perula to Cabo Corrientes A Tropical Storm Warning means that tropical storm conditions are expected somewhere within the warning area within 36 hours. A Tropical Storm Watch means that tropical storm conditions are possible within the watch area, generally within 48 hours. Interests elsewhere in southwestern Mexico should monitor the progress of Flossie. For storm information specific to your area, please monitor products issued by your national meteorological service. DISCUSSION AND OUTLOOK ---------------------- At 1200 PM CST (1800 UTC), the center of Hurricane Flossie was located near latitude 17.5 North, longitude 106.5 West. Flossie is moving toward the northwest near 10 mph (17 km/h). A general northwestward to west-northwestward motion with a slight decrease in forward speed is expected for the next few days. On the forecast track, Flossie should move away from southwestern Mexico today and tonight. Maximum sustained winds have increased to near 110 mph (175 km/h) with higher gusts. Additional strengthening is expected through Wednesday morning, and Flossie could become a major hurricane tonight or Wednesday morning. Steady to rapid weakening is expected starting late Wednesday. Hurricane-force winds extend outward up to 25 miles (35 km) from the center and tropical-storm-force winds extend outward up to 90 miles (150 km). The estimated minimum central pressure is 966 mb (28.53 inches). HAZARDS AFFECTING LAND ---------------------- Key messages for Hurricane Flossie can be found in the Tropical Cyclone Discussion under AWIPS header MIATCDEP1 and WMO header WTPZ41 KNHC. RAINFALL: Hurricane Flossie should produce additional rainfall totals of 2 to 4 inches, with isolated maximum totals of 6 inches, across coastal portions of the Mexican states of Michoacán, Colima, and Jalisco into Wednesday. This rainfall could lead to localized flash flooding. For a complete depiction of forecast rainfall associated with Hurricane Flossie, please see the National Weather Service Storm Total Rainfall Graphic available at hurricanes.gov/graphics_ep1.shtml?rainqpf WIND: Tropical storm conditions are expected within portions of the warning area, and are possible within the watch areas, for the next few hours. SURF: Swells generated by Flossie will affect portions of the coast of southwestern Mexico during the next few days. These swells are likely to cause life-threatening surf and rip current conditions. Please consult products from your local weather office. NEXT ADVISORY ------------- Next complete advisory at 300 PM CST. $$ Forecaster Kelly

5-Day Uncertainty Track last updated Tue, 01 Jul 2025 17:45:02 GMT


Wind Speed Probabilities last updated Tue, 01 Jul 2025 15:21:56 GMT

...FLOSSIE CONTINUES TO STRENGTHEN... ...OUTER RAINBANDS OF FLOSSIE BRUSHING THE COAST OF SOUTHWESTERN MEXICO... As of 12:00 PM CST Tue Jul 01 the center of Flossie was located near 17.5, -106.5 with movement NW at 10 mph. The minimum central pressure was 966 mb with maximum sustained winds of about 110 mph.

651
ABPZ20 KNHC 011733
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
1100 AM PDT Tue Jul 1 2025

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

Active Systems:
The National Hurricane Center is issuing advisories on Hurricane
Flossie, located in the eastern Pacific basin around 180 miles
offshore the coast of southwestern Mexico.

South of Southwestern Mexico:
An area of low pressure is forecast to develop several hundred miles
offshore of southwestern Mexico late this week. Environmental
conditions appear conducive for some gradual development of this
system thereafter, and a tropical depression could form over the
weekend while it moves generally west-northwestward.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...medium...40 percent.

$$
Forecaster Beven

MD 1529 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR THE MID-ATLANTIC STATES
Mesoscale Discussion 1529 NWS Storm Prediction Center Norman OK 1048 AM CDT Tue Jul 01 2025 Areas affected...the Mid-Atlantic States Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 011548Z - 011745Z Probability of Watch Issuance...95 percent SUMMARY...An increasing damaging wind threat and Severe Thunderstorm Watch issuance are expected this afternoon DISCUSSION...Convection has been slowly building across the central Appalachians, ahead of a low-amplitude shortwave trough that is progressing east across the Upper OH Valley. While there is some near-term uncertainty of how quickly this initial activity will strengthen amid weak DCAPE, the downstream airmass east of the Blue Ridge is destabilizing well as surface temperatures have already warmed into the upper 80s to low 90s. This will yield an uptick in convective intensity as clusters impinge on the Piedmont to Coastal Plain where mid 70s surface dew points are pervasive. Although lower-level winds will remain weak and predominately veered, moderate mid to upper-level westerlies will support organized multicells capable of producing multiple strong to isolated severe gust swaths. Scattered damaging winds appear likely towards mid to late afternoon. ..Grams/Mosier.. 07/01/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PHI...AKQ...CTP...LWX... LAT...LON 40117372 39117452 37967617 37757901 38627929 40127907 40667848 40497568 40117372 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1228 PM CDT Tue Jul 01 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE NORTHERN ROCKIES AND UPPER MIDWEST INTO THE GREAT LAKES... ...SUMMARY... At least scattered storms are possible across a large portion of the continental U.S. on Wednesday. Isolated severe gusts may accompany the stronger storms over portions of the Northern Rockies and the Upper Midwest to central Michigan region. ...Synopsis... A mid-level trough will amplify while tracking toward New England, with an upper ridge poised to build over the central U.S. as another mid-level trough impinges on the Pacific Northwest tomorrow (Wednesday). Widespread, rich low-level moisture will encourage at least scattered thunderstorm development across much of the CONUS. However, the best chance for strong to isolated severe thunderstorms will be over parts of the Northern Rockies and the Upper Midwest/Great Lakes regions. Here, low-level moisture and instability will best overlap with modest mid-level westerly flow along the periphery of the upper ridge, where some vertical wind shear will be present to encourage storm organization. ...Portions of the Northern Rockies... Through the day, surface heating will support mixing of a dry boundary layer, which may deepen to 500 mb in spots. Tropospheric lapse rates will steepen to around 9 C/km, boosting SBCAPE into the 500-1500 J/kg range. High-based thunderstorms should develop by afternoon peak heating. Modest mid-level flow along the periphery of the ridge will overspread the dry boundary layer, resulting in elongated, straight hodographs and 30 kts of effective bulk shear. Multicell structures or perhaps a transient supercell will be the likely storm modes. Given the dry boundary layer, the stronger storm cores may produce a few severe gusts. ...Upper Midwest into the Great Lakes... Along the eastern periphery of the upper ridge, broad northwesterly mid/upper flow will overspread the Upper Midwest and Great Lakes region during the afternoon. Modest low-level moisture and mid-level lapse rates will contribute to 1000-2000 J/kg MLCAPE by afternoon peak heating. A belt of stronger northwesterly 500 mb flow will overspread the Great Lakes as the eastern trough deepens in the 18-00Z time frame, contributing to vertical speed shear and elongated, straight hodographs. Over 30 kts of unidirectional effective bulk shear will support multicells capable of producing a few instances of severe wind and/or hail. ..Squitieri.. 07/01/2025 Read more