Storm Prediction Center

WW 0356 Status Updates
STATUS REPORT ON WW 356 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1217 ..SQUITIERI..06/21/26 ATTN...WFO...CYS...UNR...RIW... STATUS REPORT FOR WS 356 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC013-045-157-165-210140- NE . NEBRASKA COUNTIES INCLUDED ARE BOX BUTTE DAWES SCOTTS BLUFF SIOUX SDC047-210140- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE FALL RIVER WYC001-015-021-045-210140- WY . WYOMING COUNTIES INCLUDED ARE ALBANY GOSHEN LARAMIE WESTON Read more

WW 356 SEVERE TSTM NE SD WY 201925Z - 210300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 356 NWS Storm Prediction Center Norman OK 125 PM MDT Sat Jun 20 2026 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Nebraska Panhandle Southwest South Dakota Central and Eastern Wyoming * Effective this Saturday afternoon and evening from 125 PM until 900 PM MDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible A tornado or two possible SUMMARY...Clusters of high-based thunderstorms will affect much of central Wyoming this afternoon, capable of locally damaging wind gusts. Other supercell storms capable of large hail and damaging winds will be a concern over eastern Wyoming and the Nebraska Panhandle later this afternoon. The severe thunderstorm watch area is approximately along and 85 statute miles north and south of a line from 15 miles west southwest of Lander WY to 40 miles east northeast of Scottsbluff NE. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU6). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26030. ...Hart Read more

MD 1214 CONCERNING TORNADO AND SEVERE THUNDERSTORM WATCHES 357...358... FOR PORTIONS OF FAR EASTERN COLORADO...EXTREME SOUTHWESTERN NEBRASKA...AND WESTERN KANSAS
Mesoscale Discussion 1214 NWS Storm Prediction Center Norman OK 0542 PM CDT Sat Jun 20 2026 Areas affected...portions of far eastern Colorado...extreme southwestern Nebraska...and western Kansas Concerning...Tornado and Severe Thunderstorm Watches 357...358... Valid 202242Z - 210045Z The severe weather threat for Tornado and Severe Thunderstorm Watches 357, 358 continues. SUMMARY...All severe hazards are possible over the next couple of hours. However, ongoing storms should merge into an MCS and support a potential severe wind swath between 00-04Z. A few gusts may reach 85-100 mph. DISCUSSION...Multiple HP supercells, with a history of hail 1-3 inches in diameter, and measured gusts up to 90 mph (89 mph measured by NSSL mobile unit), are in the process of gradually merging along the KS/NE border, with a convective outflow boundary noted across Cheyenne into Rawlins Counties. Over the next couple of hours, the more intense and discrete updrafts will persist with a severe hail threat, with a few stones exceeding 2 inches in diameter. While storms may become outflow dominant, an additional tornado or two may still occur given the amount of low-level shear concentrated along the warm front. Over the next few hours, the supercells are expected to merge into a cold-pool-driven MCS, which will surge southward this evening. Given preceding 8-8.5 C/km mid-level lapse rates, and a corridor of 50-60 kt bulk shear vectors oriented roughly normal to the expected MCS leading-line orientation, the MCS could become highly organized and produce a severe wind swath. This swath will most likely occur somewhere in the 00-04Z period, containing abundant gusts in the 60-70 mph range, with the strongest gusts possibly reaching 85-100 mph, as suggested by some of the latest HRRR and WoFS runs. ..Squitieri.. 06/20/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ICT...GID...DDC...GLD...PUB...BOU... LAT...LON 37100100 37220202 37360271 37460296 37660304 38750300 39130299 39800287 40200216 40310147 40280061 40059973 39779902 39229880 38349877 37749879 37329960 37150024 37100100 MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH MOST PROBABLE PEAK WIND GUST...85-100 MPH MOST PROBABLE PEAK HAIL SIZE...2.00-3.50 IN Read more

MD 1216 CONCERNING TORNADO AND SEVERE THUNDERSTORM WATCHES 357...358... FOR PORTIONS OF WESTERN KANSAS
Mesoscale Discussion 1216 NWS Storm Prediction Center Norman OK 0708 PM CDT Sat Jun 20 2026 Areas affected...portions of western Kansas Concerning...Tornado and Severe Thunderstorm Watches 357...358... Valid 210008Z - 210045Z The severe weather threat for Tornado and Severe Thunderstorm Watches 357, 358 continues. SUMMARY...A severe wind swath is beginning, with up to 100 mph gusts likely over the next couple of hours. DISCUSSION...Merging supercells have recently formed into a cold-pool-driven MCS. In the last 30 minutes, multiple measured gusts over 90 mph and appreciable damage have been reported in the Colby, KS vicinity. Some bowing tendencies have been noted with this MCS, with KDDC radar inbound velocity data showing the onset of a rear-inflow jet developing with the aid of remnant supercell mesocyclones, which may be transitioning to effective book-end vorticies. This convective morphology is unfolding within a highly favorable mesoscale setup, with the MCS bow echo structure roughly traversing a retreating baroclinic boundary, amid 2500-3000 J/kg MLCAPE and 60+ kts of effective bulk shear perpendicular to the MCS leading line. Several 75+ mph gusts are expected, with some potentially reaching 100 mph over the next couple of hours. ..Squitieri.. 06/21/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...DDC...GLD... LAT...LON 39360079 39240037 38930020 38450016 38330018 38270053 38300105 38370136 38530139 39010133 39260116 39300104 39360079 MOST PROBABLE PEAK TORNADO INTENSITY...100-125 MPH MOST PROBABLE PEAK WIND GUST...85-100 MPH MOST PROBABLE PEAK HAIL SIZE...1.00-1.75 IN Read more

WW 0359 Status Updates
STATUS FOR WATCH 0359 HAS NOT BEEN ISSUED YET Read more

WW 0356 Status Updates
STATUS REPORT ON WW 356 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 20 SE LAR TO 35 S DGW TO 40 SSE GCC. ..SQUITIERI..06/20/26 ATTN...WFO...CYS...UNR...RIW... STATUS REPORT FOR WS 356 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS NEC013-045-157-165-210040- NE . NEBRASKA COUNTIES INCLUDED ARE BOX BUTTE DAWES SCOTTS BLUFF SIOUX SDC047-210040- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE FALL RIVER WYC001-005-009-015-019-021-027-031-045-210040- WY . WYOMING COUNTIES INCLUDED ARE ALBANY CAMPBELL CONVERSE GOSHEN JOHNSON LARAMIE NIOBRARA PLATTE WESTON Read more

WW 0357 Status Updates
STATUS REPORT ON WW 357 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 15 SE LIC TO 30 NNW GLD TO 25 ESE IML TO 40 ENE MCK. ..SQUITIERI..06/20/26 ATTN...WFO...GLD...BOU...CYS...LBF... STATUS REPORT FOR WT 357 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC017-063-210040- CO . COLORADO COUNTIES INCLUDED ARE CHEYENNE KIT CARSON KSC023-039-063-065-109-137-153-179-181-193-199-210040- KS . KANSAS COUNTIES INCLUDED ARE CHEYENNE DECATUR GOVE GRAHAM LOGAN NORTON RAWLINS SHERIDAN SHERMAN THOMAS WALLACE NEC007-033-087-105-123-145-210040- NE . NEBRASKA COUNTIES INCLUDED ARE BANNER CHEYENNE HITCHCOCK Read more

WW 0358 Status Updates
STATUS REPORT ON WW 358 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..SQUITIERI..06/20/26 ATTN...WFO...PUB...DDC...GLD... STATUS REPORT FOR WS 358 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS COC009-011-025-061-089-099-210040- CO . COLORADO COUNTIES INCLUDED ARE BACA BENT CROWLEY KIOWA OTERO PROWERS KSC051-055-057-067-069-071-075-081-083-093-101-119-129-135-165- 171-175-187-189-195-203-210040- KS . KANSAS COUNTIES INCLUDED ARE ELLIS FINNEY FORD GRANT GRAY GREELEY HAMILTON HASKELL HODGEMAN KEARNY LANE MEADE MORTON NESS RUSH SCOTT SEWARD STANTON STEVENS TREGO WICHITA THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL Read more

No Mesoscale Discussions are in effect as of Sat Jun 20 22:26:08 UTC 2026.

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0348 PM CDT Sat Jun 20 2026 Valid 221200Z - 281200Z ...Synopsis... To start next week, the western states will be under a brief period of zonal flow aloft, though embedded shortwave troughs will provide opportunity for breezy surface winds, before ridging returns to the Intermountain West. This pattern will reinforce warmer-than-normal and dry conditions, continuing to accelerate fuel desiccation across the region. A high centered near the AZ/NM borders will persist long enough that moisture will begin to advect north and eastward over the larger Four Corners region. Conversely, expansive troughing will dominate the Northeast, sending periodic cold fronts and widespread precipitation across the eastern United States to suppress regional fire threats there. The consensus among the latest long-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. As this high breaks down, additional fire weather concerns will be possible late next week. ...Southwest and southern Great Basin... ...Day 4/Tuesday... As high pressure builds over the Southwest, hot and dry surface conditions will promote deep boundary layer mixing, contributing to increased westerly surface winds. As such, an area of 40 percent probability of Critical wind/RH continues over portions of northern AZ and far southern UT. ...Day 5/Wednesday and Day 6/Thursday... Persistent high pressure over the Southwest will eventually lead to increasing moisture wrapped in from the Gulf of California. It appears that this moisture will begin to reach eastern AZ and western NM followed by UT and CO mid-next-week. As is typical with this pattern, hot and dry air at the surface will lag increasing moisture aloft, leading to high-based thunderstorms. Expect adjustments in time/space with future forecast issuances as the timing and placement of this potential moisture becomes more clear. The consensus among the latest mid-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. ..Stearns.. 06/20/2026 ...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 0348 PM CDT Sat Jun 20 2026 Valid 221200Z - 281200Z ...Synopsis... To start next week, the western states will be under a brief period of zonal flow aloft, though embedded shortwave troughs will provide opportunity for breezy surface winds, before ridging returns to the Intermountain West. This pattern will reinforce warmer-than-normal and dry conditions, continuing to accelerate fuel desiccation across the region. A high centered near the AZ/NM borders will persist long enough that moisture will begin to advect north and eastward over the larger Four Corners region. Conversely, expansive troughing will dominate the Northeast, sending periodic cold fronts and widespread precipitation across the eastern United States to suppress regional fire threats there. The consensus among the latest long-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. As this high breaks down, additional fire weather concerns will be possible late next week. ...Southwest and southern Great Basin... ...Day 4/Tuesday... As high pressure builds over the Southwest, hot and dry surface conditions will promote deep boundary layer mixing, contributing to increased westerly surface winds. As such, an area of 40 percent probability of Critical wind/RH continues over portions of northern AZ and far southern UT. ...Day 5/Wednesday and Day 6/Thursday... Persistent high pressure over the Southwest will eventually lead to increasing moisture wrapped in from the Gulf of California. It appears that this moisture will begin to reach eastern AZ and western NM followed by UT and CO mid-next-week. As is typical with this pattern, hot and dry air at the surface will lag increasing moisture aloft, leading to high-based thunderstorms. Expect adjustments in time/space with future forecast issuances as the timing and placement of this potential moisture becomes more clear. The consensus among the latest mid-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. ..Stearns.. 06/20/2026 ...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 0348 PM CDT Sat Jun 20 2026 Valid 221200Z - 281200Z ...Synopsis... To start next week, the western states will be under a brief period of zonal flow aloft, though embedded shortwave troughs will provide opportunity for breezy surface winds, before ridging returns to the Intermountain West. This pattern will reinforce warmer-than-normal and dry conditions, continuing to accelerate fuel desiccation across the region. A high centered near the AZ/NM borders will persist long enough that moisture will begin to advect north and eastward over the larger Four Corners region. Conversely, expansive troughing will dominate the Northeast, sending periodic cold fronts and widespread precipitation across the eastern United States to suppress regional fire threats there. The consensus among the latest long-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. As this high breaks down, additional fire weather concerns will be possible late next week. ...Southwest and southern Great Basin... ...Day 4/Tuesday... As high pressure builds over the Southwest, hot and dry surface conditions will promote deep boundary layer mixing, contributing to increased westerly surface winds. As such, an area of 40 percent probability of Critical wind/RH continues over portions of northern AZ and far southern UT. ...Day 5/Wednesday and Day 6/Thursday... Persistent high pressure over the Southwest will eventually lead to increasing moisture wrapped in from the Gulf of California. It appears that this moisture will begin to reach eastern AZ and western NM followed by UT and CO mid-next-week. As is typical with this pattern, hot and dry air at the surface will lag increasing moisture aloft, leading to high-based thunderstorms. Expect adjustments in time/space with future forecast issuances as the timing and placement of this potential moisture becomes more clear. The consensus among the latest mid-term forecast guidance is that this pattern will be temporary with the Southwest high expected to weaken by late next week. ..Stearns.. 06/20/2026 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0358 Status Updates
STATUS FOR WATCH 0358 HAS NOT BEEN ISSUED YET Read more

WW 358 SEVERE TSTM CO KS 202035Z - 210300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 358 NWS Storm Prediction Center Norman OK 335 PM CDT Sat Jun 20 2026 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Colorado Southwest Kansas * Effective this Saturday afternoon and evening from 335 PM until 1000 PM CDT. * Primary threats include... Scattered large hail and isolated very large hail events to 3 inches in diameter likely Scattered damaging wind gusts to 70 mph likely A tornado or two possible SUMMARY...Thunderstorms will develop over southeast Colorado this afternoon and spread eastward into southwest Kansas. A hot and humid air mass is present, favorable for severe storms capable of damaging winds and large hail. A tornado or two cannot be ruled out. The severe thunderstorm watch area is approximately along and 60 statute miles north and south of a line from 40 miles west southwest of Lamar CO to 40 miles northeast of Dodge City KS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU8). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Severe Thunderstorm Watch means conditions are favorable for severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. Severe thunderstorms can and occasionally do produce tornadoes. && OTHER WATCH INFORMATION...CONTINUE...WW 356...WW 357... AVIATION...A few severe thunderstorms with hail surface and aloft to 3 inches. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 27030. ...Hart Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Jun 20 2026 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms remain likely across parts of the central Plains mainly this afternoon and evening. Large to very large hail, severe winds (some 75+ mph), and a few tornadoes are possible. ...20z Update WY/NE/CO/KS... Scattered severe storms are likely over much of the central High Plains this afternoon and evening. Incipient convection is developing over the higher terrain/foothills and should spread eastward into a moist and destabilizing air mass. Aided by strong ascent from an upper trough and mid-level jet (observed via 18z RAOBs), supercells and organized clusters remain likely. All hazards are expected, with a focus for a few more persistent supercells and a strong tornado or two along a notable differential heating axis in southwestern NE. With time upscale growth into and MCS is likely tonight with a risk for damaging winds into the central Plains. Minor adjustments were made to the probabilities for the latest observed trends. For short term information see MCD #1212. ...Great Basin... Scattered thunderstorms have developed over parts of NV and southern ID along a diffuse frontal zone. While moisture is limited, enough instability beneath the passing upper trough will support the potential for a few severe gusts. 5% wind probabilities were extended westward. See MCD #1213 for more info. ...Southeast... Scattered to widespread thunderstorms continue across much of the Gulf Coast and Southeast States this afternoon. Sporadic damaging gusts remain possible with the stronger clusters across northern FL and southern LA. Weak shear will preclude much if any storm organization. 5% wind probabilities were adjusted to better match damaging wind potential. ..Lyons.. 06/20/2026 .PREV DISCUSSION... /ISSUED 1109 AM CDT Sat Jun 20 2026/ ...Central Plains... Water vapor imagery shows a shortwave trough over ID/UT tracking eastward toward the central High Plains. Southerly/southeasterly low-level winds ahead of this feature over parts of eastern CO/western NE/KS will help to maintain a moist and moderately unstable air mass across the region, especially as low clouds continue to burn off and afternoon heating commences. Scattered thunderstorm development is expected by mid-afternoon over central WY down into central CO in favored terrain/convergence areas. This activity will spread eastward into a progressively more moist/unstable air mass and intensify into supercells. A corridor of favorable vertical shear will develop later today from northeast CO into southwest NE/northwest KS for isolated tornadoes. Otherwise, very large hail and damaging winds will be the main concerns. Activity is likely to organize upscale during the evening and spread across KS with a damaging wind risk persisting much of the night. ...Southeast... A very moist and moderately unstable air mass is present again today over much of the southeast US. Most CAM solutions suggest scattered afternoon thunderstorms across this area, including along the FL east coast. Dewpoints in the 70s and PWAT values around 2 inches, coupled with strong daytime heating and steep low-level lapse rates suggest a risk of locally gusty/damaging wind gusts in the most intense cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Jun 20 2026 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms remain likely across parts of the central Plains mainly this afternoon and evening. Large to very large hail, severe winds (some 75+ mph), and a few tornadoes are possible. ...20z Update WY/NE/CO/KS... Scattered severe storms are likely over much of the central High Plains this afternoon and evening. Incipient convection is developing over the higher terrain/foothills and should spread eastward into a moist and destabilizing air mass. Aided by strong ascent from an upper trough and mid-level jet (observed via 18z RAOBs), supercells and organized clusters remain likely. All hazards are expected, with a focus for a few more persistent supercells and a strong tornado or two along a notable differential heating axis in southwestern NE. With time upscale growth into and MCS is likely tonight with a risk for damaging winds into the central Plains. Minor adjustments were made to the probabilities for the latest observed trends. For short term information see MCD #1212. ...Great Basin... Scattered thunderstorms have developed over parts of NV and southern ID along a diffuse frontal zone. While moisture is limited, enough instability beneath the passing upper trough will support the potential for a few severe gusts. 5% wind probabilities were extended westward. See MCD #1213 for more info. ...Southeast... Scattered to widespread thunderstorms continue across much of the Gulf Coast and Southeast States this afternoon. Sporadic damaging gusts remain possible with the stronger clusters across northern FL and southern LA. Weak shear will preclude much if any storm organization. 5% wind probabilities were adjusted to better match damaging wind potential. ..Lyons.. 06/20/2026 .PREV DISCUSSION... /ISSUED 1109 AM CDT Sat Jun 20 2026/ ...Central Plains... Water vapor imagery shows a shortwave trough over ID/UT tracking eastward toward the central High Plains. Southerly/southeasterly low-level winds ahead of this feature over parts of eastern CO/western NE/KS will help to maintain a moist and moderately unstable air mass across the region, especially as low clouds continue to burn off and afternoon heating commences. Scattered thunderstorm development is expected by mid-afternoon over central WY down into central CO in favored terrain/convergence areas. This activity will spread eastward into a progressively more moist/unstable air mass and intensify into supercells. A corridor of favorable vertical shear will develop later today from northeast CO into southwest NE/northwest KS for isolated tornadoes. Otherwise, very large hail and damaging winds will be the main concerns. Activity is likely to organize upscale during the evening and spread across KS with a damaging wind risk persisting much of the night. ...Southeast... A very moist and moderately unstable air mass is present again today over much of the southeast US. Most CAM solutions suggest scattered afternoon thunderstorms across this area, including along the FL east coast. Dewpoints in the 70s and PWAT values around 2 inches, coupled with strong daytime heating and steep low-level lapse rates suggest a risk of locally gusty/damaging wind gusts in the most intense cores. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0257 PM CDT Sat Jun 20 2026 Valid 202000Z - 211200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE CENTRAL PLAINS... ...SUMMARY... Severe thunderstorms remain likely across parts of the central Plains mainly this afternoon and evening. Large to very large hail, severe winds (some 75+ mph), and a few tornadoes are possible. ...20z Update WY/NE/CO/KS... Scattered severe storms are likely over much of the central High Plains this afternoon and evening. Incipient convection is developing over the higher terrain/foothills and should spread eastward into a moist and destabilizing air mass. Aided by strong ascent from an upper trough and mid-level jet (observed via 18z RAOBs), supercells and organized clusters remain likely. All hazards are expected, with a focus for a few more persistent supercells and a strong tornado or two along a notable differential heating axis in southwestern NE. With time upscale growth into and MCS is likely tonight with a risk for damaging winds into the central Plains. Minor adjustments were made to the probabilities for the latest observed trends. For short term information see MCD #1212. ...Great Basin... Scattered thunderstorms have developed over parts of NV and southern ID along a diffuse frontal zone. While moisture is limited, enough instability beneath the passing upper trough will support the potential for a few severe gusts. 5% wind probabilities were extended westward. See MCD #1213 for more info. ...Southeast... Scattered to widespread thunderstorms continue across much of the Gulf Coast and Southeast States this afternoon. Sporadic damaging gusts remain possible with the stronger clusters across northern FL and southern LA. Weak shear will preclude much if any storm organization. 5% wind probabilities were adjusted to better match damaging wind potential. ..Lyons.. 06/20/2026 .PREV DISCUSSION... /ISSUED 1109 AM CDT Sat Jun 20 2026/ ...Central Plains... Water vapor imagery shows a shortwave trough over ID/UT tracking eastward toward the central High Plains. Southerly/southeasterly low-level winds ahead of this feature over parts of eastern CO/western NE/KS will help to maintain a moist and moderately unstable air mass across the region, especially as low clouds continue to burn off and afternoon heating commences. Scattered thunderstorm development is expected by mid-afternoon over central WY down into central CO in favored terrain/convergence areas. This activity will spread eastward into a progressively more moist/unstable air mass and intensify into supercells. A corridor of favorable vertical shear will develop later today from northeast CO into southwest NE/northwest KS for isolated tornadoes. Otherwise, very large hail and damaging winds will be the main concerns. Activity is likely to organize upscale during the evening and spread across KS with a damaging wind risk persisting much of the night. ...Southeast... A very moist and moderately unstable air mass is present again today over much of the southeast US. Most CAM solutions suggest scattered afternoon thunderstorms across this area, including along the FL east coast. Dewpoints in the 70s and PWAT values around 2 inches, coupled with strong daytime heating and steep low-level lapse rates suggest a risk of locally gusty/damaging wind gusts in the most intense cores. Read more

MD 1213 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHERN UTAH INTO SOUTHEAST IDAHO
Mesoscale Discussion 1213 NWS Storm Prediction Center Norman OK 0233 PM CDT Sat Jun 20 2026 Areas affected...Northern Utah into southeast Idaho Concerning...Severe potential...Watch unlikely Valid 201933Z - 202130Z Probability of Watch Issuance...20 percent SUMMARY...Isolated strong to severe downburst winds will be possible through early evening across the northern Great Basin into far southwest Wyoming. This threat should remain sufficiently isolated to preclude watch issuance. DISCUSSION...The early stages of thunderstorm initiation are ongoing across northern NV and into adjacent portions of southern ID and northwest UT. This activity is largely being driven by large-scale ascent in proximity to a mid-level vorticity maximum evident in recent water-vapor imagery, and is being aided by localized orographic ascent within the higher terrain features. Across much of northeast NV into UT/ID, temperatures are warming into the mid 70s to low 80s with dewpoint depressions increasing into the 30-40 F range, indicative of deep boundary-layer mixing. Recent RAP mesoanalyses corroborate these observations and suggest 0-3 km lapse rates are nearly dry adiabatic. While dry low-level conditions are limiting overall buoyancy, the boundary-layer thermodynamic conditions are favorable for downdraft accelerations capable of producing strong to severe downburst winds. Additionally, 20-30 knots of bulk shear through the CAPE-bearing layer should provide some storm longevity, further supporting the potential for strong/severe winds. In general, thunderstorm coverage should remain isolated to perhaps widely scattered, and the downburst wind threat associated with any particular storm should remain relatively transient (10-30 minutes). These factors limit confidence in the need for a watch. ..Moore/Hart.. 06/20/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...RIW...SLC...PIH...BOI...LKN... LAT...LON 41531057 41021089 40531174 40031345 39981385 40021433 40441523 40811592 40871709 40931777 41061807 41201818 41511820 41861812 42031794 42181770 42331727 42501398 42661310 43191149 43181097 42971074 42511070 41531057 MOST PROBABLE PEAK WIND GUST...55-70 MPH Read more

MD 1211 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR WYOMING
Mesoscale Discussion 1211 NWS Storm Prediction Center Norman OK 0150 PM CDT Sat Jun 20 2026 Areas affected...Wyoming Concerning...Severe potential...Watch possible Valid 201850Z - 202045Z Probability of Watch Issuance...40 percent SUMMARY...High-based thunderstorms capable of severe downburst winds will spread across central and northeast Wyoming through the afternoon. Trends are being monitored for the need for a watch issuance, though thunderstorm coverage remains uncertain. DISCUSSION...Over the past 1-2 hours, relatively shallow, but high-based, convection has begun spreading across western WY with a second region of storms more recently developing within the Wyoming Basin/southern WY. Across both regions, clearing skies ahead of the developing storms has allowed surface temperatures to warm into the 70s with dewpoints mixing into the mid to upper 30s. Based on recent forecast guidance, these surface conditions suggest that the boundary-layer has now fully mixed to around 3 to 3.5 km deep with around 250-500 J/kg of MLCAPE. Although buoyancy is fairly meager, the combination of a deeply mixed boundary layer and 30-35 knots of effective shear should promote persistent convection capable of producing strong to severe downburst winds. Latest CAM guidance continues to depict this threat well and suggests swaths of 50-75 mph winds may emerge across central to northeast WY through the early evening hours. The primary uncertainty in the short-term forecast is the lingering cloud cover further downstream across central/northeast WY, which is muting diurnal heating (temperatures remain in the 60s) and limiting boundary-layer depth. Although this cloud cover is rapidly progressing northeast, it is unclear if the window of mostly clear skies will be sufficient to produce a deeply-mixed boundary layer conducive for severe winds. Consequently, confidence in the severe wind threat is greatest in the near-term, but some severe wind threat may materialize further downstream through the evening if sufficient heating can occur. Convective trends are being monitored, and watch issuance may be needed. ..Moore/Hart.. 06/20/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...CYS...BYZ...RIW... LAT...LON 41590803 41560864 41810917 42790999 43380985 43820942 44730731 44770647 44650585 44370528 44010471 43560421 43280411 43290414 42950408 42050407 41540430 41260460 41160491 41210540 41490579 41700619 41790658 41750715 41590803 MOST PROBABLE PEAK WIND GUST...65-80 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN Read more

MD 1212 CONCERNING SEVERE POTENTIAL...WATCH LIKELY FOR PARTS OF EASTERN COLORADO...SOUTHWESTERN NEBRASKA...WESTERN KANSAS
Mesoscale Discussion 1212 NWS Storm Prediction Center Norman OK 0211 PM CDT Sat Jun 20 2026 Areas affected...parts of eastern Colorado...southwestern Nebraska...western Kansas Concerning...Severe potential...Watch likely Valid 201911Z - 202115Z Probability of Watch Issuance...80 percent SUMMARY...Intensifying scattered thunderstorm development increasingly probable by 2-4 PM MDT, with a few supercells evolving thereafter. This may be accompanied by increasing potential for a couple of strong tornadoes, mainly in a corridor west through south of the Imperial, NE vicinity toward early evening. DISCUSSION...Beneath a plume of very warm (including 14-16 C+ temperatures around 700 mb) elevated mixed-layer advecting east of the southern Rockies, a surface low is beginning to develop within rapidly deepening surface troughing across eastern Colorado. This is coinciding with strong boundary heating and deep mixing, to the south of a zone of strengthening differential surface heating evolving to the north of the developing low, across parts of northwestern Kansas into the southern slopes of the Cheyenne Ridge. Along and to the cooler side of this boundary, higher boundary-layer moisture content and potential instability (including CAPE exceeding 2000 J/kg) are forecast to be maintained through the afternoon. Even to the south of this boundary, the more deeply mixed boundary-layer is forecast to become characterized by modest (but increasing across the plains toward the Kansas state border) CAPE, as convective temperatures are approached later this afternoon. Inhibition may remain strong along the zone of differential heating, but forcing for ascent associated with focused low-level convergence and warm advection may eventually contribute to isolated supercell development. In the presence of strengthening deep-layer and low-level shear, this may be accompanied by increasing potential for a strong tornado or two, in addition to large hail, by early evening, if not earlier. Otherwise, high-based convective development now underway across and to the east of the higher terrain is expected to continue to spread eastward across the plains and intensify, with scattered thunderstorms increasingly probable by 20-22Z. This will be accompanied by increasing potential for large hail, locally damaging wind gusts, and perhaps at least some risk for a couple of tornadoes as well. ..Kerr/Hart.. 06/20/2026 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...DDC...GLD...PUB...BOU...CYS... LAT...LON 41060388 41090243 40420074 39400063 38270150 37160181 37170326 37510356 38450320 39330408 40290403 41060388 Read more