Severe Storms

SPC 0600Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 0100 AM CDT Sun Aug 11 2019 Valid 121200Z - 131200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS FROM A PORTION OF THE MIDDLE AND UPPER MS VALLEY INTO THE OHIO VALLEY REGIONS... ...SUMMARY... Severe storms will be possible on Monday, mainly from a portion of the Middle and upper Mississippi Valley to the Ohio Valley. ...Synopsis... Northern-stream upper trough will deamplify as it moves through the northern Plains and upper MS Valley region Monday. The trough will be accompanied by a cold front that should extend from central ND southward through western NE by Monday evening. Farther south a low-amplitude, convectively enhanced shortwave trough will move from the NE/IA area into the southern Great Lakes and OH Valley during the evening into the overnight. At the start of the period, a cold front will extend from a surface low in southeast NE into western KS. A quasi-stationary front will extend eastward from the low through southern IA then southeast as a warm front toward the TN Valley. ...Middle Mississippi Valley into the Ohio Valley regions... Storms should be ongoing from eastern NE into IA in association with the progressive, low-amplitude shortwave trough and will continue east within zone of isentropic ascent north of the front and on nose of an eastward-migrating low-level jet. Additional storms may be ongoing farther southeast from northern MO into IL in vicinity of the warm front. Current expectation is that much of this activity will probably diminish as it spreads eastward toward the OH Valley. These storms may reinforce the stationary/warm front or may result in an effective boundary being farther south than the synoptic fronts. The warm sector is expected to become moderately to strongly unstable supported by surface dewpoints in the 70s F and diabatic warming of the boundary layer. Eastward destabilization toward the OH Valley will occur during the evening. Storms are expected to redevelop in vicinity of the effective boundaries from the middle MS Valley and toward the OH Valley. This region will reside within belt of stronger winds aloft with 40-55 kt effective bulk shear supportive of organized storms including supercells. Storms may eventually evolve into an MCS as they develop eastward through the OH Valley during the evening. All severe threats will be possible, but primary threat will probably transition to damaging wind as activity grows upscale. An upgrade to higher probabilities may ultimately be needed for a portion of this region. However, ongoing uncertainties regarding mesoscale details related to evolution of the morning convection precludes further refinement for this update. ...Northern Plains region... The atmosphere may become at least marginally unstable east of a cold front across the eastern Dakotas and into eastern NE where a belt of stronger winds within base of the northern-stream shortwave trough will reside. A few storms may redevelop in this region during the afternoon, posing some risk for hail or locally strong wind gusts. ...Maine... A few storms may develop along pre-frontal trough during the afternoon where modest low-level moisture and mid-level lapse rates will support marginal instability. This region will reside within belt of stronger winds aloft within base of an amplifying upper trough supporting 35-40 kt effective shear. A few storms may produce locally strong wind gusts and small to marginally severe hail, but overall threat should remain limited by the expected weak thermodynamic environment. ...MAXIMUM RISK BY HAZARD... Tornado: 5% - Slight Wind: 15% - Slight Hail: 15% - Slight ..Dial.. 08/11/2019 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1240 AM CDT Sun Aug 11 2019 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS THE CENTRAL HIGH PLAINS... ...SUMMARY... Areas of strong to severe storms are expected over portions of the northern through central High Plains Sunday afternoon into Sunday night. Large hail and severe gusts are the primary threats. ...High Plains... Early-morning water-vapor imagery depicts a well-defined mid-level short-wave trough over the Pacific northwest, shifting east in line with short-range model guidance. This feature is forecast to shift into western MT/ID by 12/00z which will result in roughly 30m 12hr 500mb height falls across the northern High Plains of MT/WY. In response to the short wave, low-level flow should remain decidedly easterly as a surface low develops over north-central WY. With seasonally high-PW values expected to hold across this region, instability should be more than adequate for robust updrafts. Latest guidance suggests strongest boundary-layer heating will be noted across ID/southern MT/western WY and forecast soundings depict uncapped soundings by 19-20z over the higher terrain. Latest thinking is discrete supercells should evolve over southwestern MT by early afternoon. This activity should then spread/develop east toward the High Plains where low-level moisture will be more conducive for higher buoyancy and perhaps a tornado threat. Otherwise, damaging winds and hail are expected with storms as they spread toward the western Dakotas. Farther south, low-latitude disturbance is gyrating north along the AZ/NM border around the west side of an upper ridge. This feature should translate into south-central CO late Sunday afternoon with a corridor of stronger mid-level flow forecast to extend downstream into the central High Plains. Large-scale forcing ahead of this feature should encourage convective development across the higher terrain early in the period. It appears robust thunderstorms will evolve along the Front Range of CO into southeast WY by 20-21z then spread/develop east. This activity will propagate along cool side of a pronounced surface boundary that should drape itself along the I-70 corridor across northeast CO/KS. Forecast soundings favor supercells, and early activity should prove discrete. However, upward-evolving complex of storms is expected and an organized squall line along the leading edge of an MCS should advance east as LLJ focuses into south-central NE late. Damaging winds are possible if this activity evolves as expected. Otherwise, hail and perhaps a tornado may be noted with early supercells. ..Darrow/Cook.. 08/11/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Sun Aug 11 2019 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... The northern Rockies mid-level trough responsible for heightened fire weather concerns the past few days will continue to weaken and lift northeastward toward the Plains/southern Canadian provinces. In the wake of this system, zonal mid-level flow will extend across the northern tier of the CONUS along with weaker mid-level flow compared to recent days. This pattern will translate to weaker low-level flow across dry areas of the West. Outside of locally elevated fire weather conditions across Wyoming and vicinity, the overall pattern will be quiet and no highlights are needed for this outlook. ..Cook.. 08/11/2019 ...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 1230 AM CDT Sun Aug 11 2019 Valid 121200Z - 131200Z ...NO CRITICAL AREAS... ...Synopsis... The northern Rockies mid-level trough responsible for heightened fire weather concerns the past few days will continue to weaken and lift northeastward toward the Plains/southern Canadian provinces. In the wake of this system, zonal mid-level flow will extend across the northern tier of the CONUS along with weaker mid-level flow compared to recent days. This pattern will translate to weaker low-level flow across dry areas of the West. Outside of locally elevated fire weather conditions across Wyoming and vicinity, the overall pattern will be quiet and no highlights are needed for this outlook. ..Cook.. 08/11/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Sun Aug 11 2019 Valid 111200Z - 121200Z ...Synopsis... Fire weather conditions will gradually improve compared to prior days. A longwave trough initially over Oregon will continue to weaken and lift northeastward toward the northern Rockies. As this occurs, a mid-level jet streak on the periphery of the trough will migrate toward Idaho/Wyoming through peak heating hours. Meanwhile, the widespread thunderstorms observed over Washington/Oregon/northern California and vicinity will diminish significantly as the region comes under the influence of mid/upper subsidence behind the trough. ...Eastern Idaho and western/central Wyoming... Vertical mixing processes beneath the approaching mid-level jet streak will result in areas of 15-25 mph surface winds during peak heating hours - strongest over the Snake River Valley of Idaho and also into southwestern/central Wyoming. RH values will only fall to critical thresholds on a localized basis and will be lowest in central Wyoming (15-30% elsewhere). The atmospheric conditions are most consistent with elevated fire weather thresholds, and the ongoing delineation remains in place for this outlook given the existence of dry fuels across the region. ..Cook.. 08/11/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1230 AM CDT Sun Aug 11 2019 Valid 111200Z - 121200Z ...Synopsis... Fire weather conditions will gradually improve compared to prior days. A longwave trough initially over Oregon will continue to weaken and lift northeastward toward the northern Rockies. As this occurs, a mid-level jet streak on the periphery of the trough will migrate toward Idaho/Wyoming through peak heating hours. Meanwhile, the widespread thunderstorms observed over Washington/Oregon/northern California and vicinity will diminish significantly as the region comes under the influence of mid/upper subsidence behind the trough. ...Eastern Idaho and western/central Wyoming... Vertical mixing processes beneath the approaching mid-level jet streak will result in areas of 15-25 mph surface winds during peak heating hours - strongest over the Snake River Valley of Idaho and also into southwestern/central Wyoming. RH values will only fall to critical thresholds on a localized basis and will be lowest in central Wyoming (15-30% elsewhere). The atmospheric conditions are most consistent with elevated fire weather thresholds, and the ongoing delineation remains in place for this outlook given the existence of dry fuels across the region. ..Cook.. 08/11/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 1696 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR NORTHWESTERN AND NORTH CENTRAL KANSAS INTO SOUTHERN NEBRASKA
Mesoscale Discussion 1696 NWS Storm Prediction Center Norman OK 1143 PM CDT Sat Aug 10 2019 Areas affected...northwestern and north central Kansas into southern Nebraska Concerning...Severe potential...Watch possible Valid 110443Z - 110615Z Probability of Watch Issuance...40 percent SUMMARY...A cluster of strong storms has accelerated across portions of northwestern Kansas, with attendant damaging wind and large hail risk. WW may be needed. DISCUSSION...A cluster of storms which moved out of eastern Colorado into northwest Kansas, has recently produced a downburst, with measured winds to 75 MPH observed in Thomas County KS. This cluster of storms is expanding along the outflow, both north and south, and is moving quickly east-northeastward at near 40 kt. A very moist/unstable airmass exists ahead of the convection, with surface southeasterly winds veering/increasing to southwesterly at 30 kt at 1km per the latest DDC VWP, and then on around to westerly through mid levels. It appears possible that the moist/unstable low-level inflow may continue to sustain the storms, and with deep-layer shear supportive of organized updrafts, risk for damaging winds and hail -- and even a brief tornado -- appears to exist locally. Depending upon evolution of this convection in the near term, a downstream WW may be required. ..Goss/Hart.. 08/11/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OAX...TOP...ICT...GID...DDC...GLD... LAT...LON 38670092 39410126 40000109 40569908 40419722 39769720 38999910 38670092 Read more

WW 0568 Status Updates
STATUS REPORT ON WW 568 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 N DGW TO 20 S GCC TO 30 NNW GCC TO 65 SW MLS TO 20 N BIL TO 30 WSW 3HT. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1695 ..COOK..08/11/19 ATTN...WFO...BYZ...UNR...RIW... STATUS REPORT FOR WS 568 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-037-065-075-087-103-107-110340- MT . MONTANA COUNTIES INCLUDED ARE CARTER GOLDEN VALLEY MUSSELSHELL POWDER RIVER ROSEBUD TREASURE WHEATLAND SDC019-033-047-081-093-102-103-110340- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE BUTTE CUSTER FALL RIVER LAWRENCE MEADE OGLALA LAKOTA PENNINGTON WYC005-011-045-110340- WY 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 0567 Status Updates
STATUS REPORT ON WW 567 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 NNW LVM TO 20 WNW BZN TO 30 E BTM TO 15 SE HLN TO 25 E GTF. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1695 ..COOK..08/11/19 ATTN...WFO...BOI...MSO...PIH...TFX... STATUS REPORT FOR WS 567 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC007-027-043-045-059-110340- MT . MONTANA COUNTIES INCLUDED ARE BROADWATER FERGUS JEFFERSON JUDITH BASIN MEAGHER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES CLEARED FROM SEVERE THUNDERSTORM AND TORNADO WATCHES. 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

MD 1695 CONCERNING SEVERE THUNDERSTORM WATCH 567...568... FOR SOUTHERN MONTANA...NORTHEAST WYOMING...AND WESTERN SOUTH DAKOTA
Mesoscale Discussion 1695 NWS Storm Prediction Center Norman OK 0934 PM CDT Sat Aug 10 2019 Areas affected...southern Montana...northeast Wyoming...and western South Dakota Concerning...Severe Thunderstorm Watch 567...568... Valid 110234Z - 110400Z The severe weather threat for Severe Thunderstorm Watch 567, 568 continues. SUMMARY...Local severe risk -- mainly in the form of gusty/damaging winds -- continues, but should gradually diminish over the next 1-2 hours. DISCUSSION...Latest IR satellite and radar loops show convection gradually decreasing in intensity across WW 567 and 568, with the most persistent/intense storms occurring across portions of southwestern Montana, as well as over northeast Wyoming -- within WW 568. Here, local severe risk continues. Otherwise, a continued diurnally driven decrease in storm intensity is expected through watch expiration. ..Goss.. 08/11/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LBF...UNR...CYS...BYZ...GGW...RIW...TFX...MSO... LAT...LON 46151044 45941209 46771247 46911068 46490559 44910197 42710179 43320697 44920754 46150994 46151044 Read more

WW 0568 Status Updates
STATUS REPORT ON WW 568 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 35 NNW DGW TO 35 SW GCC TO 40 E SHR TO 55 NNE SHR TO 55 E BIL TO 20 N BIL TO 30 WSW 3HT. ..COOK..08/11/19 ATTN...WFO...BYZ...UNR...RIW... STATUS REPORT FOR WS 568 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS MTC011-037-065-075-087-103-107-110240- MT . MONTANA COUNTIES INCLUDED ARE CARTER GOLDEN VALLEY MUSSELSHELL POWDER RIVER ROSEBUD TREASURE WHEATLAND SDC019-033-047-081-093-102-103-110240- SD . SOUTH DAKOTA COUNTIES INCLUDED ARE BUTTE CUSTER FALL RIVER LAWRENCE MEADE OGLALA LAKOTA PENNINGTON WYC005-011-045-110240- WY . WYOMING COUNTIES INCLUDED ARE Read more

WW 0567 Status Updates
STATUS REPORT ON WW 567 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 WNW MYL TO 15 ENE MYL TO 30 SSW SMN TO 30 WNW MQM TO 20 SSE DLN TO 25 ENE DLN TO 10 ESE HLN TO 25 E GTF. ..COOK..08/11/19 ATTN...WFO...BOI...MSO...PIH...TFX... STATUS REPORT FOR WS 567 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS IDC001-003-015-027-037-039-045-073-075-085-087-110240- ID . IDAHO COUNTIES INCLUDED ARE ADA ADAMS BOISE CANYON CUSTER ELMORE GEM OWYHEE PAYETTE VALLEY WASHINGTON MTC007-027-031-043-045-057-059-110240- MT . MONTANA COUNTIES INCLUDED ARE BROADWATER FERGUS GALLATIN JEFFERSON JUDITH BASIN MADISON MEAGHER THE WATCH STATUS MESSAGE IS FOR GUIDANCE PURPOSES ONLY. PLEASE REFER TO WATCH COUNTY NOTIFICATION STATEMENTS FOR OFFICIAL INFORMATION ON COUNTIES...INDEPENDENT CITIES AND MARINE ZONES Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sat Aug 10 2019 Valid 110100Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN ROCKIES/HIGH PLAINS AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms will continue this evening across the northern Rockies region into the central High Plains. Wind and hail remain the primary threats. ...01z Update... Scattered robust convection continues across the northern Rockies, arcing east-southeast over southern MT into the Black Hills region. This activity is partly driven by a weak short-wave trough that is ejecting across western MT ahead of the main Pacific northwest trough. Given the large-scale support, scattered severe thunderstorms should focus along a corridor primarily across southern MT into northeast WY through late evening. Farther south across the central High Plains, scattered thunderstorms developed within easterly low-level flow regime over northeast CO/southwest NE. This activity is beginning to cluster and an MCS may ultimately evolve over south-central NE/north-central KS along nose of LLJ. Have adjusted severe probs to account for this higher severe probability development. ..Darrow.. 08/11/2019 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sat Aug 10 2019 Valid 110100Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN ROCKIES/HIGH PLAINS AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms will continue this evening across the northern Rockies region into the central High Plains. Wind and hail remain the primary threats. ...01z Update... Scattered robust convection continues across the northern Rockies, arcing east-southeast over southern MT into the Black Hills region. This activity is partly driven by a weak short-wave trough that is ejecting across western MT ahead of the main Pacific northwest trough. Given the large-scale support, scattered severe thunderstorms should focus along a corridor primarily across southern MT into northeast WY through late evening. Farther south across the central High Plains, scattered thunderstorms developed within easterly low-level flow regime over northeast CO/southwest NE. This activity is beginning to cluster and an MCS may ultimately evolve over south-central NE/north-central KS along nose of LLJ. Have adjusted severe probs to account for this higher severe probability development. ..Darrow.. 08/11/2019 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sat Aug 10 2019 Valid 110100Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN ROCKIES/HIGH PLAINS AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms will continue this evening across the northern Rockies region into the central High Plains. Wind and hail remain the primary threats. ...01z Update... Scattered robust convection continues across the northern Rockies, arcing east-southeast over southern MT into the Black Hills region. This activity is partly driven by a weak short-wave trough that is ejecting across western MT ahead of the main Pacific northwest trough. Given the large-scale support, scattered severe thunderstorms should focus along a corridor primarily across southern MT into northeast WY through late evening. Farther south across the central High Plains, scattered thunderstorms developed within easterly low-level flow regime over northeast CO/southwest NE. This activity is beginning to cluster and an MCS may ultimately evolve over south-central NE/north-central KS along nose of LLJ. Have adjusted severe probs to account for this higher severe probability development. ..Darrow.. 08/11/2019 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sat Aug 10 2019 Valid 110100Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN ROCKIES/HIGH PLAINS AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms will continue this evening across the northern Rockies region into the central High Plains. Wind and hail remain the primary threats. ...01z Update... Scattered robust convection continues across the northern Rockies, arcing east-southeast over southern MT into the Black Hills region. This activity is partly driven by a weak short-wave trough that is ejecting across western MT ahead of the main Pacific northwest trough. Given the large-scale support, scattered severe thunderstorms should focus along a corridor primarily across southern MT into northeast WY through late evening. Farther south across the central High Plains, scattered thunderstorms developed within easterly low-level flow regime over northeast CO/southwest NE. This activity is beginning to cluster and an MCS may ultimately evolve over south-central NE/north-central KS along nose of LLJ. Have adjusted severe probs to account for this higher severe probability development. ..Darrow.. 08/11/2019 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0743 PM CDT Sat Aug 10 2019 Valid 110100Z - 111200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS THE NORTHERN ROCKIES/HIGH PLAINS AND THE CENTRAL HIGH PLAINS... ...SUMMARY... Scattered severe thunderstorms will continue this evening across the northern Rockies region into the central High Plains. Wind and hail remain the primary threats. ...01z Update... Scattered robust convection continues across the northern Rockies, arcing east-southeast over southern MT into the Black Hills region. This activity is partly driven by a weak short-wave trough that is ejecting across western MT ahead of the main Pacific northwest trough. Given the large-scale support, scattered severe thunderstorms should focus along a corridor primarily across southern MT into northeast WY through late evening. Farther south across the central High Plains, scattered thunderstorms developed within easterly low-level flow regime over northeast CO/southwest NE. This activity is beginning to cluster and an MCS may ultimately evolve over south-central NE/north-central KS along nose of LLJ. Have adjusted severe probs to account for this higher severe probability development. ..Darrow.. 08/11/2019 Read more

WW 0567 Status Updates
STATUS REPORT ON WW 567 THE SEVERE WEATHER THREAT CONTINUES ACROSS THE ENTIRE WATCH AREA. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1692 ..COOK..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- 110040- 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- 093-110040- MT . MONTANA COUNTIES INCLUDED ARE BEAVERHEAD BROADWATER DEER LODGE FERGUS GALLATIN GRANITE JEFFERSON JUDITH BASIN LEWIS AND CLARK MADISON MEAGHER MINERAL MISSOULA POWELL RAVALLI Read more