Severe Storms

WW 0568 Status Updates
STATUS REPORT ON WW 568 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..COOK..08/10/19 ATTN...WFO...BYZ...UNR...RIW... STATUS REPORT FOR WS 568 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC003-009-011-037-065-067-075-087-095-097-103-107-111-102340- MT . MONTANA COUNTIES INCLUDED ARE BIG HORN CARBON CARTER GOLDEN VALLEY MUSSELSHELL PARK POWDER RIVER ROSEBUD STILLWATER SWEET GRASS TREASURE WHEATLAND YELLOWSTONE SDC019-033-047-081-093-102-103-102340- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE BUTTE CUSTER FALL RIVER LAWRENCE MEADE OGLALA LAKOTA PENNINGTON WYC003-005-011-019-033-043-045-102340- WY . WYOMING COUNTIES INCLUDED ARE Read more

WW 567 SEVERE TSTM ID MT 101935Z - 110300Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 567 NWS Storm Prediction Center Norman OK 135 PM MDT Sat Aug 10 2019 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Idaho Western Montana * Effective this Saturday afternoon and evening from 135 PM until 900 PM MDT. * Primary threats include... Scattered large hail and isolated very large hail events to 2 inches in diameter possible Scattered damaging wind gusts to 70 mph possible SUMMARY...Scattered thunderstorms will develop from the Oregon-Idaho border region across southwest Montana. Some of these should become strong to severe, producing large hail and damaging winds. The severe thunderstorm watch area is approximately along and 115 statute miles north and south of a line from 35 miles west northwest of Boise ID to 60 miles southeast of Helena MT. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU7). 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 21030. ...Grams Read more

WW 568 SEVERE TSTM MT SD WY 102105Z - 110400Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 568 NWS Storm Prediction Center Norman OK 305 PM MDT Sat Aug 10 2019 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southern Montana Western South Dakota Northern Wyoming * Effective this Saturday afternoon and evening from 305 PM until 1000 PM MDT. * Primary threats include... Isolated significant damaging wind gusts to 75 mph possible Isolated very large hail events to 2 inches in diameter possible SUMMARY...Scattered thunderstorms will pose a risk for isolated severe hail and wind into late evening. The severe thunderstorm watch area is approximately along and 75 statute miles north and south of a line from 65 miles south southwest of Harlowton MT to 45 miles east of Rapid City SD. 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 567... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 550. Mean storm motion vector 25030. ...Grams Read more

WW 0568 Status Updates
STATUS FOR WATCH 0568 HAS NOT BEEN ISSUED YET Read more

MD 1691 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR SOUTHERN MN...WESTERN/CENTRAL IA
Mesoscale Discussion 1691 NWS Storm Prediction Center Norman OK 0356 PM CDT Sat Aug 10 2019 Areas affected...Southern MN...Western/central IA Concerning...Severe potential...Watch unlikely Valid 102056Z - 102300Z Probability of Watch Issuance...20 percent SUMMARY...At least isolated thunderstorm development is possible this afternoon. The strongest cells will be capable of producing locally damaging wind and perhaps a tornado or two. Due to uncertainty regarding the coverage of the threat, watch issuance is currently considered unlikely. DISCUSSION...The latest surface analysis depicts a weak surface low across southwest MN, with a surface boundary extending eastward across southern MN and then southeastward into northeastern IA. A zone of weakly confluent flow, likely related to differential heating, is also noted extending south of the low into western IA. Widespread cloudiness has limited heating across the region, but rich low-level moisture is supporting MLCAPE ranging from 500 J/kg across the eastern portion of the MCD area to around 2000 J/kg across the western portion. Thunderstorm development will be possible later this afternoon near these surface features, with the greatest threat likely near the confluence zone across northwest/north-central IA where somewhat greater destabilization is occurring. Moderate mid/upper-level flow is resulting in effective shear of 40-50 kt across the region, more than sufficient for organized storm structures (including supercells) should convection develop. Warm midlevel temperatures and generally weak midlevel lapse rates are likely to mitigate the severe threat (especially hail) to some extent, but eventual development of one or two supercells is possible. Locally damaging wind would be the primary threat, but a tornado or two would also be possible, given favorable boundary-layer moisture and marginally supportive low-level shear profiles. Watch issuance is currently considered unlikely due to uncertainty regarding the number of storms that can develop across this region. However, this will be re-evaluated if multiple organized cells appear imminent. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MPX...DMX...FSD... LAT...LON 41379495 42219508 43389523 44169532 44389491 44339399 44029329 42499301 41769330 41539377 41379495 Read more

WW 0567 Status Updates
STATUS REPORT ON WW 567 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. ..EDWARDS..08/10/19 ATTN...WFO...BOI...MSO...PIH...TFX... STATUS REPORT FOR WS 567 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IDC001-003-015-027-035-037-039-045-049-059-073-075-085-087- 102140- ID . IDAHO COUNTIES INCLUDED ARE ADA ADAMS BOISE CANYON CLEARWATER CUSTER ELMORE GEM IDAHO LEMHI OWYHEE PAYETTE VALLEY WASHINGTON MTC001-007-023-027-031-039-043-045-049-057-059-061-063-077-081- 093-102140- MT . MONTANA COUNTIES INCLUDED ARE BEAVERHEAD BROADWATER DEER LODGE FERGUS GALLATIN GRANITE JEFFERSON JUDITH BASIN LEWIS AND CLARK MADISON MEAGHER MINERAL MISSOULA POWELL RAVALLI SILVER BOW Read more

MD 1690 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR SOUTHWEST ND...WESTERN SD
Mesoscale Discussion 1690 NWS Storm Prediction Center Norman OK 0256 PM CDT Sat Aug 10 2019 Areas affected...Southwest ND...Western SD Concerning...Severe potential...Watch possible Valid 101956Z - 102130Z Probability of Watch Issuance...40 percent SUMMARY...Isolated severe thunderstorms capable of large hail and severe wind will continue into late afternoon. The need for a watch is uncertain due to the limited areal coverage of the threat. DISCUSSION...A supercell has recently developed across southwest ND, with other cells attempting to develop across northeast SD, and further south over the Black Hills. Ongoing convection is being aided by moderate buoyancy (MLCAPE of 1000-1500 J/kg) and effective shear of 35-45 kt, which will continue to support a threat of isolated supercells posing a risk of large hail, severe wind gusts, and perhaps a brief tornado. The airmass downstream of ongoing activity is noticeably cooler and more stable. Thus, the eastward extent of the threat may be relatively limited, with cells exhibiting more of a rightward motion (such as the cell in southwest ND) having more of a residence time within the generally uncapped and more favorable environment. The constrained area of the threat may preclude watch issuance, though at least a couple supercells will be possible into late afternoon across a portion of the region. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...ABR...BIS...UNR... LAT...LON 43640369 44580375 45740326 46580260 46800231 46810193 46610161 46290146 45570162 44600197 43610247 43540320 43640369 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z The elevated was extended eastward into portions of central Wyoming, as the latest model guidance depicts 15-25 mph sustained westerly surface winds and corresponding 15-25% RH overlapping drier fuels here, particularly for the lower terrain areas. In addition, a few dry lightning strikes may occur within the broader area of thunderstorm activity near the Idaho/Montana border. However, the potential for Day 1 precipitation accumulation, and heavy rain from the Day 2 round, may temper the lightning-induced wildfire spread threat, thus precluding an isolated dry thunderstorm delineation at this time. Otherwise, the previous forecast remains generally on track (see below for details). ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... Fire weather conditions will gradually improve some as a persistent West Coast mid-level low weakens and migrates northeastward toward the central Rockies. Most of the thunderstorm potential evident over OR/CA and vicinity the past few days will lessen in the midst of subsidence aloft west of the mid-level trough. Meanwhile, slackening flow aloft over the Great Basin will result in weaker winds and a lessened (locally elevated) fire weather threat in these areas. A lingering risk of elevated fire weather will extend from eastern Idaho into western Wyoming Sunday afternoon. ...Eastern Idaho, far northern Utah, and western Wyoming... As the mid-level wave ejects northeastward, a belt of enhanced mid-level flow will migrate away from the western Great Basin and reach the discussion area during peak heating hours. Vertical mixing processes beneath this flow will result in areas of 15-25 mph westerly surface flow for several hours. RH values will only flirt with critical thresholds on a limited/localized basis, however, and should mitigate the overall fire risk. Dry fuels should continue to support a risk of fire spread especially with ongoing fires, however. An isolated thunderstorm may also occur especially in eastern Idaho and vicinity, though coverage atop dry fuels currently does not warrant any dry thunder delineations for this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z The elevated was extended eastward into portions of central Wyoming, as the latest model guidance depicts 15-25 mph sustained westerly surface winds and corresponding 15-25% RH overlapping drier fuels here, particularly for the lower terrain areas. In addition, a few dry lightning strikes may occur within the broader area of thunderstorm activity near the Idaho/Montana border. However, the potential for Day 1 precipitation accumulation, and heavy rain from the Day 2 round, may temper the lightning-induced wildfire spread threat, thus precluding an isolated dry thunderstorm delineation at this time. Otherwise, the previous forecast remains generally on track (see below for details). ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... Fire weather conditions will gradually improve some as a persistent West Coast mid-level low weakens and migrates northeastward toward the central Rockies. Most of the thunderstorm potential evident over OR/CA and vicinity the past few days will lessen in the midst of subsidence aloft west of the mid-level trough. Meanwhile, slackening flow aloft over the Great Basin will result in weaker winds and a lessened (locally elevated) fire weather threat in these areas. A lingering risk of elevated fire weather will extend from eastern Idaho into western Wyoming Sunday afternoon. ...Eastern Idaho, far northern Utah, and western Wyoming... As the mid-level wave ejects northeastward, a belt of enhanced mid-level flow will migrate away from the western Great Basin and reach the discussion area during peak heating hours. Vertical mixing processes beneath this flow will result in areas of 15-25 mph westerly surface flow for several hours. RH values will only flirt with critical thresholds on a limited/localized basis, however, and should mitigate the overall fire risk. Dry fuels should continue to support a risk of fire spread especially with ongoing fires, however. An isolated thunderstorm may also occur especially in eastern Idaho and vicinity, though coverage atop dry fuels currently does not warrant any dry thunder delineations for this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z The elevated was extended eastward into portions of central Wyoming, as the latest model guidance depicts 15-25 mph sustained westerly surface winds and corresponding 15-25% RH overlapping drier fuels here, particularly for the lower terrain areas. In addition, a few dry lightning strikes may occur within the broader area of thunderstorm activity near the Idaho/Montana border. However, the potential for Day 1 precipitation accumulation, and heavy rain from the Day 2 round, may temper the lightning-induced wildfire spread threat, thus precluding an isolated dry thunderstorm delineation at this time. Otherwise, the previous forecast remains generally on track (see below for details). ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... Fire weather conditions will gradually improve some as a persistent West Coast mid-level low weakens and migrates northeastward toward the central Rockies. Most of the thunderstorm potential evident over OR/CA and vicinity the past few days will lessen in the midst of subsidence aloft west of the mid-level trough. Meanwhile, slackening flow aloft over the Great Basin will result in weaker winds and a lessened (locally elevated) fire weather threat in these areas. A lingering risk of elevated fire weather will extend from eastern Idaho into western Wyoming Sunday afternoon. ...Eastern Idaho, far northern Utah, and western Wyoming... As the mid-level wave ejects northeastward, a belt of enhanced mid-level flow will migrate away from the western Great Basin and reach the discussion area during peak heating hours. Vertical mixing processes beneath this flow will result in areas of 15-25 mph westerly surface flow for several hours. RH values will only flirt with critical thresholds on a limited/localized basis, however, and should mitigate the overall fire risk. Dry fuels should continue to support a risk of fire spread especially with ongoing fires, however. An isolated thunderstorm may also occur especially in eastern Idaho and vicinity, though coverage atop dry fuels currently does not warrant any dry thunder delineations for this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0242 PM CDT Sat Aug 10 2019 Valid 111200Z - 121200Z The elevated was extended eastward into portions of central Wyoming, as the latest model guidance depicts 15-25 mph sustained westerly surface winds and corresponding 15-25% RH overlapping drier fuels here, particularly for the lower terrain areas. In addition, a few dry lightning strikes may occur within the broader area of thunderstorm activity near the Idaho/Montana border. However, the potential for Day 1 precipitation accumulation, and heavy rain from the Day 2 round, may temper the lightning-induced wildfire spread threat, thus precluding an isolated dry thunderstorm delineation at this time. Otherwise, the previous forecast remains generally on track (see below for details). ..Squitieri.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1247 AM CDT Sat Aug 10 2019/ ...Synopsis... Fire weather conditions will gradually improve some as a persistent West Coast mid-level low weakens and migrates northeastward toward the central Rockies. Most of the thunderstorm potential evident over OR/CA and vicinity the past few days will lessen in the midst of subsidence aloft west of the mid-level trough. Meanwhile, slackening flow aloft over the Great Basin will result in weaker winds and a lessened (locally elevated) fire weather threat in these areas. A lingering risk of elevated fire weather will extend from eastern Idaho into western Wyoming Sunday afternoon. ...Eastern Idaho, far northern Utah, and western Wyoming... As the mid-level wave ejects northeastward, a belt of enhanced mid-level flow will migrate away from the western Great Basin and reach the discussion area during peak heating hours. Vertical mixing processes beneath this flow will result in areas of 15-25 mph westerly surface flow for several hours. RH values will only flirt with critical thresholds on a limited/localized basis, however, and should mitigate the overall fire risk. Dry fuels should continue to support a risk of fire spread especially with ongoing fires, however. An isolated thunderstorm may also occur especially in eastern Idaho and vicinity, though coverage atop dry fuels currently does not warrant any dry thunder delineations for this outlook. ...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 0235 PM CDT Sat Aug 10 2019 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF ID/MT/WY AND EASTERN NC... ...SUMMARY... Scattered severe thunderstorms with large hail and damaging wind gusts are most likely across parts of Idaho, Montana, Wyoming, and eastern North Carolina. The severe threat should be greatest during the late afternoon to early evening. ...Discussion... Minimal adjustment was made to the previous convective outlook. ..Smith.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 10 2019/ ...Northwest... A closed mid-level low near the CA/OR coastal border will gradually evolve into an open wave while ejecting towards the OR/ID border through tonight, as other subtle speed maxima rotate around the eastern periphery of the low. A plume of weak to moderate buoyancy will develop at peak heating, arcing from OR/ID east across the northern Rockies and High Plains where scattered thunderstorms will likely form by late afternoon. Greatest effective shear should be centered across southern MT where weak low-level easterlies will be present beneath southwesterlies aloft that strengthen with height. This should yield an elongated, straight-line hodograph favorable for several splitting supercell structures. Large hail and severe wind gusts will be the primary hazards. Relatively high LCLs may limit the overall tornado threat, but brief ones are possible where 50s surface dew points can be sustained. ...Eastern NC... Sea breeze circulations along with a weakly convergent quasi-stationary front should be the focus for isolated to perhaps scattered thunderstorm development during the next few hours. Rich boundary-layer moisture characterized by low to mid 70s surface dew points exists over coastal southern NC into SC which will result in a confined corridor of MLCAPE in excess of 2000 J/kg. A few cells should briefly organize amid 30-40 kt 500-mb west-northwesterlies. Isolated large hail and damaging winds are anticipated. A marginal severe threat may persist into tonight amid weak low-level warm advection. ...Central High Plains to IA vicinity... A messy/low confidence scenario is anticipated through tonight with multiple MCVs and lingering cloud debris across the region. Forcing for ascent will likely persist across the Mid-MO Valley in a zone of low-level warm advection. Pockets of greater surface heating are apparent within cloud breaks into IA which combined with low-level moistening should support weak to moderate MLCAPE. Moderate enlargement/curvature to the low-level hodograph may foster a conditional brief tornado/locally damaging wind risk. Relatively warm profiles aloft and weak mid-level lapse rates will be unfavorable for large hail. Otherwise, scattered late afternoon storms should develop off the southern Rockies across eastern CO. Modest effective shear may be adequate to support multicell clustering as convection impinges on substantially greater buoyancy across KS/NE. Low-level warm advection will also increase across KS tonight in response to a nocturnal low-level jet, when more widespread convection is expected in the form of multiple clusters. Given the shear profiles, convection may be only weakly organized and slow-moving. But a threat for locally severe wind gusts should exist given heavy precipitation loading amid PW in excess of 2 inches. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Sat Aug 10 2019 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF ID/MT/WY AND EASTERN NC... ...SUMMARY... Scattered severe thunderstorms with large hail and damaging wind gusts are most likely across parts of Idaho, Montana, Wyoming, and eastern North Carolina. The severe threat should be greatest during the late afternoon to early evening. ...Discussion... Minimal adjustment was made to the previous convective outlook. ..Smith.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 10 2019/ ...Northwest... A closed mid-level low near the CA/OR coastal border will gradually evolve into an open wave while ejecting towards the OR/ID border through tonight, as other subtle speed maxima rotate around the eastern periphery of the low. A plume of weak to moderate buoyancy will develop at peak heating, arcing from OR/ID east across the northern Rockies and High Plains where scattered thunderstorms will likely form by late afternoon. Greatest effective shear should be centered across southern MT where weak low-level easterlies will be present beneath southwesterlies aloft that strengthen with height. This should yield an elongated, straight-line hodograph favorable for several splitting supercell structures. Large hail and severe wind gusts will be the primary hazards. Relatively high LCLs may limit the overall tornado threat, but brief ones are possible where 50s surface dew points can be sustained. ...Eastern NC... Sea breeze circulations along with a weakly convergent quasi-stationary front should be the focus for isolated to perhaps scattered thunderstorm development during the next few hours. Rich boundary-layer moisture characterized by low to mid 70s surface dew points exists over coastal southern NC into SC which will result in a confined corridor of MLCAPE in excess of 2000 J/kg. A few cells should briefly organize amid 30-40 kt 500-mb west-northwesterlies. Isolated large hail and damaging winds are anticipated. A marginal severe threat may persist into tonight amid weak low-level warm advection. ...Central High Plains to IA vicinity... A messy/low confidence scenario is anticipated through tonight with multiple MCVs and lingering cloud debris across the region. Forcing for ascent will likely persist across the Mid-MO Valley in a zone of low-level warm advection. Pockets of greater surface heating are apparent within cloud breaks into IA which combined with low-level moistening should support weak to moderate MLCAPE. Moderate enlargement/curvature to the low-level hodograph may foster a conditional brief tornado/locally damaging wind risk. Relatively warm profiles aloft and weak mid-level lapse rates will be unfavorable for large hail. Otherwise, scattered late afternoon storms should develop off the southern Rockies across eastern CO. Modest effective shear may be adequate to support multicell clustering as convection impinges on substantially greater buoyancy across KS/NE. Low-level warm advection will also increase across KS tonight in response to a nocturnal low-level jet, when more widespread convection is expected in the form of multiple clusters. Given the shear profiles, convection may be only weakly organized and slow-moving. But a threat for locally severe wind gusts should exist given heavy precipitation loading amid PW in excess of 2 inches. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Sat Aug 10 2019 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF ID/MT/WY AND EASTERN NC... ...SUMMARY... Scattered severe thunderstorms with large hail and damaging wind gusts are most likely across parts of Idaho, Montana, Wyoming, and eastern North Carolina. The severe threat should be greatest during the late afternoon to early evening. ...Discussion... Minimal adjustment was made to the previous convective outlook. ..Smith.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 10 2019/ ...Northwest... A closed mid-level low near the CA/OR coastal border will gradually evolve into an open wave while ejecting towards the OR/ID border through tonight, as other subtle speed maxima rotate around the eastern periphery of the low. A plume of weak to moderate buoyancy will develop at peak heating, arcing from OR/ID east across the northern Rockies and High Plains where scattered thunderstorms will likely form by late afternoon. Greatest effective shear should be centered across southern MT where weak low-level easterlies will be present beneath southwesterlies aloft that strengthen with height. This should yield an elongated, straight-line hodograph favorable for several splitting supercell structures. Large hail and severe wind gusts will be the primary hazards. Relatively high LCLs may limit the overall tornado threat, but brief ones are possible where 50s surface dew points can be sustained. ...Eastern NC... Sea breeze circulations along with a weakly convergent quasi-stationary front should be the focus for isolated to perhaps scattered thunderstorm development during the next few hours. Rich boundary-layer moisture characterized by low to mid 70s surface dew points exists over coastal southern NC into SC which will result in a confined corridor of MLCAPE in excess of 2000 J/kg. A few cells should briefly organize amid 30-40 kt 500-mb west-northwesterlies. Isolated large hail and damaging winds are anticipated. A marginal severe threat may persist into tonight amid weak low-level warm advection. ...Central High Plains to IA vicinity... A messy/low confidence scenario is anticipated through tonight with multiple MCVs and lingering cloud debris across the region. Forcing for ascent will likely persist across the Mid-MO Valley in a zone of low-level warm advection. Pockets of greater surface heating are apparent within cloud breaks into IA which combined with low-level moistening should support weak to moderate MLCAPE. Moderate enlargement/curvature to the low-level hodograph may foster a conditional brief tornado/locally damaging wind risk. Relatively warm profiles aloft and weak mid-level lapse rates will be unfavorable for large hail. Otherwise, scattered late afternoon storms should develop off the southern Rockies across eastern CO. Modest effective shear may be adequate to support multicell clustering as convection impinges on substantially greater buoyancy across KS/NE. Low-level warm advection will also increase across KS tonight in response to a nocturnal low-level jet, when more widespread convection is expected in the form of multiple clusters. Given the shear profiles, convection may be only weakly organized and slow-moving. But a threat for locally severe wind gusts should exist given heavy precipitation loading amid PW in excess of 2 inches. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0235 PM CDT Sat Aug 10 2019 Valid 102000Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS PARTS OF ID/MT/WY AND EASTERN NC... ...SUMMARY... Scattered severe thunderstorms with large hail and damaging wind gusts are most likely across parts of Idaho, Montana, Wyoming, and eastern North Carolina. The severe threat should be greatest during the late afternoon to early evening. ...Discussion... Minimal adjustment was made to the previous convective outlook. ..Smith.. 08/10/2019 .PREV DISCUSSION... /ISSUED 1130 AM CDT Sat Aug 10 2019/ ...Northwest... A closed mid-level low near the CA/OR coastal border will gradually evolve into an open wave while ejecting towards the OR/ID border through tonight, as other subtle speed maxima rotate around the eastern periphery of the low. A plume of weak to moderate buoyancy will develop at peak heating, arcing from OR/ID east across the northern Rockies and High Plains where scattered thunderstorms will likely form by late afternoon. Greatest effective shear should be centered across southern MT where weak low-level easterlies will be present beneath southwesterlies aloft that strengthen with height. This should yield an elongated, straight-line hodograph favorable for several splitting supercell structures. Large hail and severe wind gusts will be the primary hazards. Relatively high LCLs may limit the overall tornado threat, but brief ones are possible where 50s surface dew points can be sustained. ...Eastern NC... Sea breeze circulations along with a weakly convergent quasi-stationary front should be the focus for isolated to perhaps scattered thunderstorm development during the next few hours. Rich boundary-layer moisture characterized by low to mid 70s surface dew points exists over coastal southern NC into SC which will result in a confined corridor of MLCAPE in excess of 2000 J/kg. A few cells should briefly organize amid 30-40 kt 500-mb west-northwesterlies. Isolated large hail and damaging winds are anticipated. A marginal severe threat may persist into tonight amid weak low-level warm advection. ...Central High Plains to IA vicinity... A messy/low confidence scenario is anticipated through tonight with multiple MCVs and lingering cloud debris across the region. Forcing for ascent will likely persist across the Mid-MO Valley in a zone of low-level warm advection. Pockets of greater surface heating are apparent within cloud breaks into IA which combined with low-level moistening should support weak to moderate MLCAPE. Moderate enlargement/curvature to the low-level hodograph may foster a conditional brief tornado/locally damaging wind risk. Relatively warm profiles aloft and weak mid-level lapse rates will be unfavorable for large hail. Otherwise, scattered late afternoon storms should develop off the southern Rockies across eastern CO. Modest effective shear may be adequate to support multicell clustering as convection impinges on substantially greater buoyancy across KS/NE. Low-level warm advection will also increase across KS tonight in response to a nocturnal low-level jet, when more widespread convection is expected in the form of multiple clusters. Given the shear profiles, convection may be only weakly organized and slow-moving. But a threat for locally severe wind gusts should exist given heavy precipitation loading amid PW in excess of 2 inches. Read more

WW 0567 Status Updates
STATUS FOR WATCH 0567 HAS NOT BEEN ISSUED YET Read more

WW 0567 Status Updates
STATUS FOR WATCH 0567 HAS NOT BEEN ISSUED YET Read more

MD 1689 CONCERNING SEVERE POTENTIAL...SEVERE THUNDERSTORM WATCH LIKELY FOR PORTIONS OF SOUTHERN MT INTO NORTHERN WY
Mesoscale Discussion 1689 NWS Storm Prediction Center Norman OK 0144 PM CDT Sat Aug 10 2019 Areas affected...portions of southern MT into northern WY Concerning...Severe potential...Severe Thunderstorm Watch likely Valid 101844Z - 102015Z Probability of Watch Issuance...80 percent SUMMARY...Thunderstorms are expected to develop over the higher terrain of southern MT and northern WY in the next couple of hours. These storms will pose a threat for large hail and locally damaging gusts. DISCUSSION...Strong heating across southern MT into WY is resulting in a rapidly destabilizing airmass early this afternoon, especially in the I-90 corridor from LVM to BIL to GCC. CU have been increasing along the higher terrain of the Beartooth-Absaroka ranges as well as along the Big Horns. Some weak inhibition remains across the region per 18z mesoanalysis, and is likely suppressing the full potential of a storm near the southern end of the Big Horns over Johnson County WY. Most recently, this storm has produced hail a half an inch in diameter. Remaining inhibition should quickly erode over the next couple of hours with additional heating and as forcing for ascent increases modestly. Midlevel lapse rates are a bit more modest across this area than points further west where mid/upper level temperatures are cooler, but still favorable for large hail potential in the presence of 35+ kt effective shear. Thunderstorms should first develop along higher terrain and track east/northeast across the High Plains into early evening. Discrete cells or storm clusters with rotating updrafts will be capable of severe hail. Additionally, high-based storms with steep low-level lapse rates and inverted-v sub-cloud layer thermodynamic profiles will support locally damaging winds. How far northeast the threat may extend across eastern MT is somewhat uncertain. A weak cold front moved across parts of eastern MT and western ND this morning. The airmass across this area should remain capped and under the influence of at least weak subsidence, with the greater severe threat likely remaining south of I-94 across southeast MT. A severe thunderstorm watch will likely be needed for portions of the MCD area by 20z or 21z. ..Leitman/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...UNR...BYZ...RIW...TFX... LAT...LON 46521025 46740922 46640727 46260595 45780482 45180420 44570407 44060428 43810469 43680546 43660621 44120838 44380941 44671033 44871072 45671075 46521025 Read more

MD 1688 CONCERNING SEVERE POTENTIAL...WATCH UNLIKELY FOR NORTHERN CA...SOUTH-CENTRAL/SOUTHWEST OR
Mesoscale Discussion 1688 NWS Storm Prediction Center Norman OK 0136 PM CDT Sat Aug 10 2019 Areas affected...Northern CA...South-central/southwest OR Concerning...Severe potential...Watch unlikely Valid 101836Z - 102030Z Probability of Watch Issuance...20 percent SUMMARY...Isolated severe thunderstorms are possible into this afternoon, with the primary threats being locally severe wind gusts and marginally severe hail. Watch issuance is unlikely. DISCUSSION...At 1830Z, a longer-lived thunderstorm cluster is moving across far northeast CA, while other convection is beginning to develop across a larger portion of northern CA, in the vicinity of a seasonably strong mid/upper-level low. Despite widespread cloudiness and generally limited heating, cool temperatures aloft are supporting SBCAPE of 500-1250 J/kg across this region, per recent mesoanalyses. Deep-layer shear is rather limited in the immediate vicinity of the mid/upper low across north-central CA into southwest OR, but somewhat stronger within a belt of southerly midlevel flow to the east across northeast CA into south-central OR. Generally cool temperatures aloft and steep midlevel lapse rates will support some potential for marginally severe hail across the region into this afternoon. Where effective shear is stronger across the northeast CA into south-central OR, a somewhat greater risk for hail with more organized storm structures will be present, in addition to the threat for isolated severe wind gusts. In general, the severe threat is expected to remain too limited in coverage and magnitude for watch issuance. ..Dean/Grams.. 08/10/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...PDT...REV...MFR...STO...PQR...EKA... LAT...LON 39992118 40062318 41352323 42662293 43542246 43812192 43902115 43732058 42962008 41301989 40932002 39992118 Read more

No watches are valid as of Sat Aug 10 18:01:02 UTC 2019.