Aggregator

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0804 PM CDT Mon Jul 21 2025 Valid 220100Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN PLAINS AND ALSO A SMALL PART OF SOUTH-CENTRAL KS... ...SUMMARY... Severe thunderstorms remain possible into late tonight across parts of the northern Plains, and also through the evening across parts of south-central Kansas. ...Parts of MT into the Dakotas and northwest MN... Multiple clusters of strong to severe storms are ongoing this evening from central/southeast MT into western SD. The downstream environment is moderately to strongly unstable and favorably sheared, and these storm clusters will continue to pose a threat of hail and strong to severe gusts in the short term as they move east-northeastward. See MCD 1748 for more information regarding the short-term threat in this area. With time, a modestly increasing low-level jet may support upscale growth into an MCS somewhere from northwest SD into ND, though short-term guidance continues to vary regarding the details. Rather strong CINH across northwest SD into southwest ND may tend to delay any organized upscale growth until late tonight, though increasing low-level warm advection and steep midlevel lapse rates could help to sustain ongoing convection as it moves through this region. Any organized cluster or larger MCS that develops could pose a damaging-wind threat through the overnight hours into parts of eastern ND, northeast SD, and potentially northwest MN. ...Central/southern Plains... A large cluster of storms across north-central KS may tend to propagate south-southeastward through the evening, within a moderate to strongly unstable environment. Decreasing shear with southward extent and the influence of convective outflow across both northeast and southwest KS will eventually result in a weakening trend, but some threat for strong to severe gusts and hail may persist with this cluster through the evening. See MCD 1749 for more information. Farther south, high-based convection may persist through dusk from the TX/OK Panhandles into southwest TX, with a threat of localized strong to severe gusts. ..Dean.. 07/22/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0804 PM CDT Mon Jul 21 2025 Valid 220100Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN PLAINS AND ALSO A SMALL PART OF SOUTH-CENTRAL KS... ...SUMMARY... Severe thunderstorms remain possible into late tonight across parts of the northern Plains, and also through the evening across parts of south-central Kansas. ...Parts of MT into the Dakotas and northwest MN... Multiple clusters of strong to severe storms are ongoing this evening from central/southeast MT into western SD. The downstream environment is moderately to strongly unstable and favorably sheared, and these storm clusters will continue to pose a threat of hail and strong to severe gusts in the short term as they move east-northeastward. See MCD 1748 for more information regarding the short-term threat in this area. With time, a modestly increasing low-level jet may support upscale growth into an MCS somewhere from northwest SD into ND, though short-term guidance continues to vary regarding the details. Rather strong CINH across northwest SD into southwest ND may tend to delay any organized upscale growth until late tonight, though increasing low-level warm advection and steep midlevel lapse rates could help to sustain ongoing convection as it moves through this region. Any organized cluster or larger MCS that develops could pose a damaging-wind threat through the overnight hours into parts of eastern ND, northeast SD, and potentially northwest MN. ...Central/southern Plains... A large cluster of storms across north-central KS may tend to propagate south-southeastward through the evening, within a moderate to strongly unstable environment. Decreasing shear with southward extent and the influence of convective outflow across both northeast and southwest KS will eventually result in a weakening trend, but some threat for strong to severe gusts and hail may persist with this cluster through the evening. See MCD 1749 for more information. Farther south, high-based convection may persist through dusk from the TX/OK Panhandles into southwest TX, with a threat of localized strong to severe gusts. ..Dean.. 07/22/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0804 PM CDT Mon Jul 21 2025 Valid 220100Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN PLAINS AND ALSO A SMALL PART OF SOUTH-CENTRAL KS... ...SUMMARY... Severe thunderstorms remain possible into late tonight across parts of the northern Plains, and also through the evening across parts of south-central Kansas. ...Parts of MT into the Dakotas and northwest MN... Multiple clusters of strong to severe storms are ongoing this evening from central/southeast MT into western SD. The downstream environment is moderately to strongly unstable and favorably sheared, and these storm clusters will continue to pose a threat of hail and strong to severe gusts in the short term as they move east-northeastward. See MCD 1748 for more information regarding the short-term threat in this area. With time, a modestly increasing low-level jet may support upscale growth into an MCS somewhere from northwest SD into ND, though short-term guidance continues to vary regarding the details. Rather strong CINH across northwest SD into southwest ND may tend to delay any organized upscale growth until late tonight, though increasing low-level warm advection and steep midlevel lapse rates could help to sustain ongoing convection as it moves through this region. Any organized cluster or larger MCS that develops could pose a damaging-wind threat through the overnight hours into parts of eastern ND, northeast SD, and potentially northwest MN. ...Central/southern Plains... A large cluster of storms across north-central KS may tend to propagate south-southeastward through the evening, within a moderate to strongly unstable environment. Decreasing shear with southward extent and the influence of convective outflow across both northeast and southwest KS will eventually result in a weakening trend, but some threat for strong to severe gusts and hail may persist with this cluster through the evening. See MCD 1749 for more information. Farther south, high-based convection may persist through dusk from the TX/OK Panhandles into southwest TX, with a threat of localized strong to severe gusts. ..Dean.. 07/22/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0804 PM CDT Mon Jul 21 2025 Valid 220100Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN PLAINS AND ALSO A SMALL PART OF SOUTH-CENTRAL KS... ...SUMMARY... Severe thunderstorms remain possible into late tonight across parts of the northern Plains, and also through the evening across parts of south-central Kansas. ...Parts of MT into the Dakotas and northwest MN... Multiple clusters of strong to severe storms are ongoing this evening from central/southeast MT into western SD. The downstream environment is moderately to strongly unstable and favorably sheared, and these storm clusters will continue to pose a threat of hail and strong to severe gusts in the short term as they move east-northeastward. See MCD 1748 for more information regarding the short-term threat in this area. With time, a modestly increasing low-level jet may support upscale growth into an MCS somewhere from northwest SD into ND, though short-term guidance continues to vary regarding the details. Rather strong CINH across northwest SD into southwest ND may tend to delay any organized upscale growth until late tonight, though increasing low-level warm advection and steep midlevel lapse rates could help to sustain ongoing convection as it moves through this region. Any organized cluster or larger MCS that develops could pose a damaging-wind threat through the overnight hours into parts of eastern ND, northeast SD, and potentially northwest MN. ...Central/southern Plains... A large cluster of storms across north-central KS may tend to propagate south-southeastward through the evening, within a moderate to strongly unstable environment. Decreasing shear with southward extent and the influence of convective outflow across both northeast and southwest KS will eventually result in a weakening trend, but some threat for strong to severe gusts and hail may persist with this cluster through the evening. See MCD 1749 for more information. Farther south, high-based convection may persist through dusk from the TX/OK Panhandles into southwest TX, with a threat of localized strong to severe gusts. ..Dean.. 07/22/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0804 PM CDT Mon Jul 21 2025 Valid 220100Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FOR PARTS OF THE NORTHERN PLAINS AND ALSO A SMALL PART OF SOUTH-CENTRAL KS... ...SUMMARY... Severe thunderstorms remain possible into late tonight across parts of the northern Plains, and also through the evening across parts of south-central Kansas. ...Parts of MT into the Dakotas and northwest MN... Multiple clusters of strong to severe storms are ongoing this evening from central/southeast MT into western SD. The downstream environment is moderately to strongly unstable and favorably sheared, and these storm clusters will continue to pose a threat of hail and strong to severe gusts in the short term as they move east-northeastward. See MCD 1748 for more information regarding the short-term threat in this area. With time, a modestly increasing low-level jet may support upscale growth into an MCS somewhere from northwest SD into ND, though short-term guidance continues to vary regarding the details. Rather strong CINH across northwest SD into southwest ND may tend to delay any organized upscale growth until late tonight, though increasing low-level warm advection and steep midlevel lapse rates could help to sustain ongoing convection as it moves through this region. Any organized cluster or larger MCS that develops could pose a damaging-wind threat through the overnight hours into parts of eastern ND, northeast SD, and potentially northwest MN. ...Central/southern Plains... A large cluster of storms across north-central KS may tend to propagate south-southeastward through the evening, within a moderate to strongly unstable environment. Decreasing shear with southward extent and the influence of convective outflow across both northeast and southwest KS will eventually result in a weakening trend, but some threat for strong to severe gusts and hail may persist with this cluster through the evening. See MCD 1749 for more information. Farther south, high-based convection may persist through dusk from the TX/OK Panhandles into southwest TX, with a threat of localized strong to severe gusts. ..Dean.. 07/22/2025 Read more

WW 0535 Status Updates
STATUS FOR WATCH 0535 HAS NOT BEEN ISSUED YET Read more

MD 1748 CONCERNING SEVERE THUNDERSTORM WATCH 535... FOR SOUTHEAST MONTANA...FAR NORTHEAST WYOMING...SOUTHWEST NORTH DAKOTA...NORTHWEST SOUTH DAKOTA
Mesoscale Discussion 1748 NWS Storm Prediction Center Norman OK 0656 PM CDT Mon Jul 21 2025 Areas affected...Southeast Montana...far northeast Wyoming...southwest North Dakota...northwest South Dakota Concerning...Severe Thunderstorm Watch 535... Valid 212356Z - 220200Z The severe weather threat for Severe Thunderstorm Watch 535 continues. SUMMARY...A greater threat for severe wind gusts may develop along and north of the South Dakota/North Dakota border this evening. DISCUSSION...Initial supercells have already grown upscale into a small linear segment in southeast Montana. Strong buoyancy exists just southeast of this activity, south of a modified outflow boundary from morning convection. Given the expected strengthening of the low-level jet in the Dakotas this evening, this boundary and greater moisture/buoyancy will likely shift northward over time. The favorable wind shear within the region should allow this activity to propagate along the theta-e gradient so long as the linear segment does not move too far north too quickly (outrunning the increasing buoyancy). It is not exactly certain how far north the greater buoyancy will move this evening, but areas near and north of the South Dakota/North Dakota border will be monitored for an increasing threat of severe wind gusts into the evening. ..Wendt.. 07/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BIS...UNR...BYZ...GGW... LAT...LON 47390179 47010113 46220145 45720291 45540365 45160512 45130610 45230643 45610663 46260685 46790571 47110445 47390179 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

MD 1747 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTH-CENTRAL/NORTHEAST KS
Mesoscale Discussion 1747 NWS Storm Prediction Center Norman OK 0455 PM CDT Mon Jul 21 2025 Areas affected...North-Central/Northeast KS Concerning...Severe potential...Watch unlikely Valid 212155Z - 220000Z Probability of Watch Issuance...20 percent SUMMARY...Isolated hail and damaging gusts are possible this afternoon and evening across north-central/northeast Kansas. Limited severe coverage should preclude the need for a watch. DISCUSSION...Strong/severe thunderstorms have developed over north-central KS amid a localized area of strong buoyancy and low-level convergence. Deep-layer vertical shear is weak and overall storm motion has been very slow. Deepening cumulus is also apparent along the outflow southwestward of this storm. Ample buoyancy exists across the region, suggesting additional storm development is possible. However, given the limited shear and anticipated lack of storm organization, the overall longevity of any particular updraft should be limited. Even so, isolated hail is possible with the initial updrafts. Strong downbursts are possible as storms collapse. Farther east, outflow from earlier storms continues to push southwestward across northeast KS, with temperatures in the upper 70s and low 80s behind it. This should limit the intensity of storms across northeast KS. However, the cluster across Washington and Marshall has shown some trend towards forward propagation recently, suggesting some damaging gust are possible even as it moves into the stabilizing airmass downstream. ..Mosier/Hart.. 07/21/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...EAX...TOP...ICT...GID...DDC...GLD... LAT...LON 39929975 39989583 39029525 38389636 38730027 39929975 MOST PROBABLE PEAK WIND GUST...UP TO 60 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

000
ABNT20 KNHC 212317
TWOAT

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
800 PM EDT Mon Jul 21 2025

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

Central Tropical Atlantic (AL94):
Shower and thunderstorm activity remains disorganized associated
with a weak area of low pressure located about 800 miles
east-southeast of the Lesser Antilles. Environmental conditions are
forecast to become increasingly unfavorable for development during
the next few days while the wave moves westward at around 15 mph.
* Formation chance through 48 hours...low...10 percent.
* Formation chance through 7 days...low...10 percent.

$$
Forecaster Papin

217
ABPZ20 KNHC 212309
TWOEP

Tropical Weather Outlook
NWS National Hurricane Center Miami FL
500 PM PDT Mon Jul 21 2025

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

Well West-Southwest of the Baja California Peninsula:
A trough of low pressure located well west-southwest of the Baja
California peninsula is producing limited shower activity. The
system is moving westward into an unfavorable environment, and
development is no longer expected.
* Formation chance through 48 hours...low...near 0 percent.
* Formation chance through 7 days...low...near 0 percent.

$$
Forecaster Hagen

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0449 PM CDT Mon Jul 21 2025 Valid 231200Z - 291200Z A mid-level trough is forecast to eject across the northern Rockies and into Canada by the midweek. A portion of this trough is progged to remain as a cutoff low off the California coast D3/Wednesday through Day 6/Friday. A secondary trough will deepen across the western United States next weekend, with continued dry and occasionally breezy conditions across the Southwest, Great Basin, and Pacific Northwest. ...D3/Wednesday-D4/Thursday... Dry thunderstorm potential returns across portions of northern California into southern Oregon and eastern Nevada D3/Wednesday into D4/Thursday. Initially moisture and forcing will be modest, with potential for isolated dry thunderstorms mainly across northeastern California on D3/Wednesday, possible continuing overnight into D4/Thursday. On D4/Thursday moisture increases which will likely lead to an increase in coverage and a transition to a mix of wet/dry thunderstorms. As instability increases, lightning efficiency will increase with more widespread strikes amid critically dry fuels. As such, isolated dry thunderstorm chances were included on both days across portions of northern California into far western Utah and southern Oregon. ..Thornton.. 07/21/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0255 PM CDT Mon Jul 21 2025 Valid 212000Z - 221200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Severe thunderstorms capable of producing large hail, severe gusts, and perhaps a tornado or two will be possible late this afternoon into tonight across parts of the northern Plains. ...20Z Update... The previous forecast remains on track, and only minor adjustments were made with this update. In the northern Plains, the Slight risk was expanded eastward in portions of ND, driven by 15-percent wind probabilities. The latest model guidance is in relatively good agreement, depicting an eastward-moving cluster of storms through the early morning hours -- aided by a strengthening low-level jet and convectively augmented midlevel impulse. Farther south, the Marginal risk was expanded slightly southward across central KS. Here, continued diurnal heating/destabilization amid rich boundary-layer moisture and steep lapse rates will favor severe wind gusts with any storm clusters that evolve through this evening. ..Weinman.. 07/21/2025 .PREV DISCUSSION... /ISSUED 1132 AM CDT Mon Jul 21 2025/ ...Northern Plains into the Upper Midwest... Water-vapor imagery shows a mid-level trough progressing eastward across the Pacific Northwest towards the northern Rockies. A lead mid-level vorticity max rotating through the base of the trough is forecast to pivot east-northeastward from north-central ID into MT by the early evening. In the low levels, a stationary frontal zone extends from near the NE/SD border west-northwestward to near the ID/WY/MT border with an easterly component to the low-level flow being maintained across eastern into central portions of MT. A moisture plume protrudes northwestward along and north of this boundary with a reservoir of 70s F dewpoints over NE to lower 60s in southeast MT (850-mb dewpoints around 16 deg C per objective analysis). A notable capping inversion will likely inhibit storm development until mid afternoon and the initial storm activity will likely focus near higher terrain and over southern MT. Steep mid-level lapse rates and 30-45 kt southwesterly 500-mb flow will support supercells with large to very large hail accompanying these storms from near the Black Hills into southern MT. A tornado risk may develop where locally backed flow in the presence of smaller temperature-dewpoint spreads could evolve near the boundary. Upscale growth into one or more clusters or an MCS seems plausible this evening into the overnight as storms move/develop east into the Dakotas. ...Central Plains... No change was made to the previous forecast for the Central Plains region. Much of the central Plains will remain capped today, as the upper ridge and warm temperatures aloft exert their influence. A surface trough is expected to extend southward across the central High Plains this afternoon, and a remnant MCV related to earlier convection should move eastward along/near the NE/KS border. Both of these features may aid in at least isolated thunderstorm development this afternoon, in the presence of moderate to strong instability amid modest deep-layer shear. Isolated severe hail and wind gusts may occur with any of the more robust cores that can develop and be maintained in an otherwise weak forcing regime. ...Tennessee Valley into the Southeast... Midday visible-satellite imagery shows an agitated cumulus field from southern GA northwestward into the southern Appalachians and Cumberland Plateau. 12 UTC raobs from Jacksonville, Atlanta, and Charleston showed PW in excess of 2 inches, signifying a very moist, deep troposphere. Surface temperatures will continue to warm into the 90s F, thereby steepening 0-2 km lapse rates. As storms develop, some of the stronger water-loaded downdrafts may yield a threat for localized 50-65 mph gusts and pockets of wind damage. This activity will likely diminish by the evening. Read more