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SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0251 PM CDT Thu Jul 31 2025 Valid 312000Z - 011200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PORTIONS OF THE MID-ATLANTIC STATES AND FROM THE COLORADO FRONT RANGE INTO EASTERN AND NORTHERN WYOMING... ...SUMMARY... Severe thunderstorms capable of damaging winds are possible this afternoon and early evening across the Mid-Atlantic region. Other severe wind and hail producing storms are also possible across the central/northern High Plains. ...20z Update... The forecast remains largely on track with only minor adjustments made based on recent convective trends. Low-end/5% risk probabilities were expanded slightly across portions of the northern Rockies where recent observed dewpoint depressions and short-range forecast soundings show low-level thermodynamic environments favorable for strong/severe downburst winds and GOES imagery shows deepening convection. Elsewhere, the forecast remains on track. See the previous discussion below and MCDs #1853 and #1854 for additional details. ..Moore.. 07/31/2025 .PREV DISCUSSION... /ISSUED 1115 AM CDT Thu Jul 31 2025/ ...Mid Atlantic Region... Midday visible-satellite imagery indicates a moist airmass via a swelling cumulus field from the upper OH Valley eastward into the Mid-Atlantic states and Long Island. Additional heating of an extremely moist boundary layer (12 UTC raobs at IAD and WAL showing 17-18 g/kg lowest 100-mb mean mixing ratios), will result in temperatures warming through the 80s deg F with 74-78 dewpoints to the east of the Fall Line. An upstream mid-level shortwave trough over WI/IL will continue to progress eastward towards the region and promote the gradual southward movement of a weak cold front. Despite weak mid-level lapse rates, the aforementioned warming/destabilization through mid afternoon will promote scattered thunderstorms along/ahead of the front. Forecast hodographs will be elongated due to 50-70 kt upper-level flow, which will support storm organization in the form of multicell clusters and possibly a few weak supercell structures. Weak low-level flow and a deep/moisture-rich profile will facilitate water-loaded downdrafts with the stronger cores. Widely scattered 50-65 mph gusts capable of wind damage will be the primary severe concern before much of this activity moves east of the coast by mid evening. ...High Plains... No change from the previous forecast thinking. Weak shortwave ridging will reside across the central Rockies/plains northward into the northern High Plains. Surface observations and satellite data depict a seasonably moist airmass abutted to the Front Range and northward into the eastern WY. Heating over the higher terrain and along a residual frontal zone will aid in scattered storm development this afternoon. The strongest cells will pose some risk of hail and gusty winds over the higher terrain before spreading onto the plains by late afternoon. Forecast soundings in this region show moderately steep mid-level lapse rates, MLCAPE values of 1000-1500 J/kg, and sufficient vertical shear for transient supercell structures. Upscale growth into a linear cluster or two may evolve (supported by recent HREF guidance), and this appears most probable near the WY/CO/NE border during the early evening. A gradual transition from primarily a hail risk to a threat favoring severe gusts may occur as outflow becomes more pervasive as storm coverage and outflow increases during the evening. ...ID/Western MT... A mid-level trough over northern NV will move slowly northward through tonight into the northern Rockies. Forcing for ascent attendant to this upper feature coupled with orographic circulations will likely result in scattered storms developing by mid to late afternoon. Very steep lapse rates and dry sub-cloud layers will promote evaporative cooling and an isolated risk for severe gusts (60-70 mph) with the stronger cores and outflow surges. ...AR/LA... Scattered diurnally driven storms will likely evolve in the vicinity of a weakness in the southern U.S. mid-level anticyclone. A very moist boundary layer amid moderate buoyancy may result in a few stronger water-loaded microbursts capable of 50-65 mph gusts and pockets of wind damage. Read more

Irrigators in the Kittitas Reclamation District were notified that water deliveries would not continue through Oct. 15 but will end early on Aug. 13. The district won’t have enough water left to make the canal function. Capital Press (Salem, Ore.), July 31, 2025

WW 0562 Status Updates
040- STATUS REPORT ON WW 562 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 25 W CXY TO 30 NW PHL TO 10 E TTN. ..KERR..07/31/25 ATTN...WFO...LWX...PHI...AKQ...OKX...CTP... STATUS REPORT FOR WS 562 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS DEC001-003-005-312040- DE . DELAWARE COUNTIES INCLUDED ARE KENT NEW CASTLE SUSSEX DCC001-312040- DC . DISTRICT OF COLUMBIA COUNTIES INCLUDED ARE DISTRICT OF COLUMBIA MDC001-003-005-009-011-013-015-017-019-021-025-027-029-031-033- 035-037-039-041-043-045-047-510-312040- MD . MARYLAND COUNTIES INCLUDED ARE ALLEGANY ANNE ARUNDEL BALTIMORE CALVERT CAROLINE CARROLL Read more

SPC 1930Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0221 PM CDT Thu Jul 31 2025 Valid 021200Z - 031200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL AND SOUTHERN HIGH PLAINS...AND OVER PORTIONS OF THE SOUTHEAST... ...SUMMARY... Isolated severe storms capable of large hail and severe wind gusts are expected in the central and southern High Plains vicinity on Saturday. Additional strong storms are possible across the Southeast. ...Central/Southern High Plains... The upper ridge over the Rockies will flatten on Saturday, while a weak shortwave trough migrates across the Four Corners and into the southern/central High Plains. South/southeasterly low-level flow will maintain upper 50s to low 60s F dewpoints (perhaps mid 60s over parts of western KS into the OK/TX Panhandles). Steep midlevel lapse rates will support moderate to strong destabilization and thunderstorms are likely to develop by late afternoon. Vertical shear is forecast to remain modest, but sufficient for organized cells capable of producing locally strong outflow winds and hail. With time during the evening, some forecast guidance suggests upscale growth could occur across western KS with a small cluster or MCS moving southeast into parts of northwest OK and the OK/TX Panhandles. If this occurs, damaging wind potential may increase. If confidence in this evolution increases, higher outlook probabilities may be necessary in subsequent outlooks. ...Southeast... A surface cold front will be located in the vicinity of southern AL into southern GA on Saturday. A seasonally very moist and strongly unstable airmass will exist near the boundary. While deep layer shear will be weak, the boundary could become a focus for clustering of thunderstorm activity. Given PW values greater than 2 inches, some potential will exist for wet microbursts and/or forward propagating clusters along outflows producing sporadic/locally damaging gusts. ..Leitman.. 07/31/2025 Read more