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WW 0589 Status Updates
STATUS REPORT ON WW 589 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 45 SSW RSL TO 25 NNW RSL TO 45 NNW RSL TO 15 WSW BIE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 1765. ..MARSH..08/17/19 ATTN...WFO...TOP...EAX...ICT...DDC...GLD...GID...OAX... STATUS REPORT FOR WS 589 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC003-005-009-013-017-027-029-031-041-043-045-053-059-061-085- 087-089-091-103-105-107-111-113-115-117-121-123-127-131-139-141- 143-149-157-159-161-167-169-177-197-201-209-170940- KS . KANSAS COUNTIES INCLUDED ARE ANDERSON ATCHISON BARTON BROWN CHASE CLAY CLOUD COFFEY DICKINSON DONIPHAN DOUGLAS ELLSWORTH FRANKLIN GEARY JACKSON JEFFERSON JEWELL JOHNSON LEAVENWORTH LINCOLN LINN LYON MCPHERSON MARION MARSHALL MIAMI MITCHELL MORRIS NEMAHA OSAGE OSBORNE OTTAWA POTTAWATOMIE REPUBLIC RICE RILEY RUSSELL SALINE SHAWNEE WABAUNSEE WASHINGTON WYANDOTTE Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0300 AM CDT Sat Aug 17 2019 Valid 201200Z - 251200Z ...DISCUSSION... Models are in reasonable agreement with the large-scale pattern through Thursday/D6, showing an upper high moving from the Plains westward toward the Four Corners, and a large trough amplification over much of eastern Canada. This trough will bring strengthening northwest flow aloft across the upper MS Valley on Tuesday/D4, and across the Upper Great Lakes on Wednesday/D5. The greatest threat of severe storms will be on Tuesday/D4, potentially the final day of strong to extreme instability for the forecast period. MUCAPE is forecast to range from 3000-5000 J/kg from eastern NE across much of IA, IL, and MO, on the southern fringe of the stronger winds aloft. ECMWF and MREF members generally show severe storm potential within this corridor, beginning late Tuesday/D4 afternoon over NE, and perhaps early in the day over IA, and continuing through the night across MO and IL. Given the glancing/subtle height falls with the upper trough to the north, and the possibility of early storms over IA, will defer possible upgrades to later outlooks. Damaging winds will be the primary concern on Tuesday/D4. For the period Wednesday D5 through Saturday/D8, models show storm chances translating southward across the central and eventually southern Plains as a front shifts south, but instability will be lessening. In addition, winds aloft will remain weak in these areas. As such, only isolated severe is expected during this time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0300 AM CDT Sat Aug 17 2019 Valid 201200Z - 251200Z ...DISCUSSION... Models are in reasonable agreement with the large-scale pattern through Thursday/D6, showing an upper high moving from the Plains westward toward the Four Corners, and a large trough amplification over much of eastern Canada. This trough will bring strengthening northwest flow aloft across the upper MS Valley on Tuesday/D4, and across the Upper Great Lakes on Wednesday/D5. The greatest threat of severe storms will be on Tuesday/D4, potentially the final day of strong to extreme instability for the forecast period. MUCAPE is forecast to range from 3000-5000 J/kg from eastern NE across much of IA, IL, and MO, on the southern fringe of the stronger winds aloft. ECMWF and MREF members generally show severe storm potential within this corridor, beginning late Tuesday/D4 afternoon over NE, and perhaps early in the day over IA, and continuing through the night across MO and IL. Given the glancing/subtle height falls with the upper trough to the north, and the possibility of early storms over IA, will defer possible upgrades to later outlooks. Damaging winds will be the primary concern on Tuesday/D4. For the period Wednesday D5 through Saturday/D8, models show storm chances translating southward across the central and eventually southern Plains as a front shifts south, but instability will be lessening. In addition, winds aloft will remain weak in these areas. As such, only isolated severe is expected during this time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0300 AM CDT Sat Aug 17 2019 Valid 201200Z - 251200Z ...DISCUSSION... Models are in reasonable agreement with the large-scale pattern through Thursday/D6, showing an upper high moving from the Plains westward toward the Four Corners, and a large trough amplification over much of eastern Canada. This trough will bring strengthening northwest flow aloft across the upper MS Valley on Tuesday/D4, and across the Upper Great Lakes on Wednesday/D5. The greatest threat of severe storms will be on Tuesday/D4, potentially the final day of strong to extreme instability for the forecast period. MUCAPE is forecast to range from 3000-5000 J/kg from eastern NE across much of IA, IL, and MO, on the southern fringe of the stronger winds aloft. ECMWF and MREF members generally show severe storm potential within this corridor, beginning late Tuesday/D4 afternoon over NE, and perhaps early in the day over IA, and continuing through the night across MO and IL. Given the glancing/subtle height falls with the upper trough to the north, and the possibility of early storms over IA, will defer possible upgrades to later outlooks. Damaging winds will be the primary concern on Tuesday/D4. For the period Wednesday D5 through Saturday/D8, models show storm chances translating southward across the central and eventually southern Plains as a front shifts south, but instability will be lessening. In addition, winds aloft will remain weak in these areas. As such, only isolated severe is expected during this time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0300 AM CDT Sat Aug 17 2019 Valid 201200Z - 251200Z ...DISCUSSION... Models are in reasonable agreement with the large-scale pattern through Thursday/D6, showing an upper high moving from the Plains westward toward the Four Corners, and a large trough amplification over much of eastern Canada. This trough will bring strengthening northwest flow aloft across the upper MS Valley on Tuesday/D4, and across the Upper Great Lakes on Wednesday/D5. The greatest threat of severe storms will be on Tuesday/D4, potentially the final day of strong to extreme instability for the forecast period. MUCAPE is forecast to range from 3000-5000 J/kg from eastern NE across much of IA, IL, and MO, on the southern fringe of the stronger winds aloft. ECMWF and MREF members generally show severe storm potential within this corridor, beginning late Tuesday/D4 afternoon over NE, and perhaps early in the day over IA, and continuing through the night across MO and IL. Given the glancing/subtle height falls with the upper trough to the north, and the possibility of early storms over IA, will defer possible upgrades to later outlooks. Damaging winds will be the primary concern on Tuesday/D4. For the period Wednesday D5 through Saturday/D8, models show storm chances translating southward across the central and eventually southern Plains as a front shifts south, but instability will be lessening. In addition, winds aloft will remain weak in these areas. As such, only isolated severe is expected during this time frame. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0300 AM CDT Sat Aug 17 2019 Valid 201200Z - 251200Z ...DISCUSSION... Models are in reasonable agreement with the large-scale pattern through Thursday/D6, showing an upper high moving from the Plains westward toward the Four Corners, and a large trough amplification over much of eastern Canada. This trough will bring strengthening northwest flow aloft across the upper MS Valley on Tuesday/D4, and across the Upper Great Lakes on Wednesday/D5. The greatest threat of severe storms will be on Tuesday/D4, potentially the final day of strong to extreme instability for the forecast period. MUCAPE is forecast to range from 3000-5000 J/kg from eastern NE across much of IA, IL, and MO, on the southern fringe of the stronger winds aloft. ECMWF and MREF members generally show severe storm potential within this corridor, beginning late Tuesday/D4 afternoon over NE, and perhaps early in the day over IA, and continuing through the night across MO and IL. Given the glancing/subtle height falls with the upper trough to the north, and the possibility of early storms over IA, will defer possible upgrades to later outlooks. Damaging winds will be the primary concern on Tuesday/D4. For the period Wednesday D5 through Saturday/D8, models show storm chances translating southward across the central and eventually southern Plains as a front shifts south, but instability will be lessening. In addition, winds aloft will remain weak in these areas. As such, only isolated severe is expected during this time frame. Read more

MD 1765 CONCERNING SEVERE THUNDERSTORM WATCH 589... FOR KANSAS AND NORTHWEST MISSOURI
Mesoscale Discussion 1765 NWS Storm Prediction Center Norman OK 0240 AM CDT Sat Aug 17 2019 Areas affected...kansas and northwest Missouri Concerning...Severe Thunderstorm Watch 589... Valid 170740Z - 170915Z The severe weather threat for Severe Thunderstorm Watch 589 continues. SUMMARY...Thunderstorms continue across much of Kansas and are spreading into northwest Missouri. Large hail and a gusty thunderstorm winds are the main threats. DISCUSSION...Multiple clusters of thunderstorms persist this morning across much of northern Kansas and into northwest Missouri. The mesoscale airmass across the region remains supportive of severe thunderstorms -- namely large hail and gusty thunderstorm winds -- as evidenced by most-unstable CAPE values in excess of 3000 J/kg and deep layer shear between 30-50 knots. One negative to a more widespread severe episode is the number of ongoing/developing storms tapping into this airmass, which should locally reduce the overall instability. The result should be a gradual weakening of overall thunderstorm intensity and a transition to a more episodic severe threat, especially across north-central Kansas where previous thunderstorm duration and ongoing thunderstorm coverage is greatest. Farther east, where the airmass is less contaminated by early convection, a more sustained severe potential will exist initially, before a gradual weakening trend takes hold. Large hail and damaging winds will be the primary severe threats. ..Marsh.. 08/17/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LSX...SGF...EAX...OAX...TOP...ICT...GID...DDC... GLD... LAT...LON 38240156 38680158 38700146 39110151 39120135 39530135 39579959 40029960 39989824 40339828 40369692 40519690 40509647 40289647 40259503 40149502 40119462 40019464 40019426 40139421 40119378 40229375 40249339 40049334 40039232 39269230 39229242 38999258 38939249 38699262 38689304 38509306 38529348 38219356 38209406 38019407 38059599 38159598 38179631 38069634 38099715 38209716 38179849 38269854 38259901 38339904 38349963 38259959 38240156 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Sat Aug 17 2019 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Isolated severe storms are possible over parts of the northern Plains Monday evening and overnight. ...Synopsis and Discussion... A negative-tilt shortwave trough will quickly move from southern Ontario across Quebec, followed closely by another area of cyclonic flow aloft amplifying over SK and MB. The southern periphery of the stronger flow aloft will affect parts of the Dakotas and MN late in the day when subtle height falls will commence. At the surface, a wind shift/weak front will approach the central Dakotas by late afternoon with a plume of mid to upper 60s F dewpoints spreading northward out of the central Plains ahead of the front. Strong instability will develop across this region, but capping will mitigate storm formation during much of the day. Isolated storms are possible along the front by late afternoon or early evening, aided by heating and modest low-level warm advection with 20 kt 850 mb flow. Additional nocturnal storms, likely elevated, are possible into western MN and southward along the MO River in the warm advection regime, and where instability will remain strong. Hail appears to be the main threat with this activity. Models suggest an increase in storm coverage, possibly an MCS, after 12Z Tuesday which is later than previously forecast. As such, have reduced severe probabilities for expected isolated coverage on Monday. Elsewhere, scattered storms are possible from the mid MS Valley across the OH Valley, where instability will remain strong but with rising heights aloft and weak shear. ..Jewell.. 08/17/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Sat Aug 17 2019 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Isolated severe storms are possible over parts of the northern Plains Monday evening and overnight. ...Synopsis and Discussion... A negative-tilt shortwave trough will quickly move from southern Ontario across Quebec, followed closely by another area of cyclonic flow aloft amplifying over SK and MB. The southern periphery of the stronger flow aloft will affect parts of the Dakotas and MN late in the day when subtle height falls will commence. At the surface, a wind shift/weak front will approach the central Dakotas by late afternoon with a plume of mid to upper 60s F dewpoints spreading northward out of the central Plains ahead of the front. Strong instability will develop across this region, but capping will mitigate storm formation during much of the day. Isolated storms are possible along the front by late afternoon or early evening, aided by heating and modest low-level warm advection with 20 kt 850 mb flow. Additional nocturnal storms, likely elevated, are possible into western MN and southward along the MO River in the warm advection regime, and where instability will remain strong. Hail appears to be the main threat with this activity. Models suggest an increase in storm coverage, possibly an MCS, after 12Z Tuesday which is later than previously forecast. As such, have reduced severe probabilities for expected isolated coverage on Monday. Elsewhere, scattered storms are possible from the mid MS Valley across the OH Valley, where instability will remain strong but with rising heights aloft and weak shear. ..Jewell.. 08/17/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Sat Aug 17 2019 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Isolated severe storms are possible over parts of the northern Plains Monday evening and overnight. ...Synopsis and Discussion... A negative-tilt shortwave trough will quickly move from southern Ontario across Quebec, followed closely by another area of cyclonic flow aloft amplifying over SK and MB. The southern periphery of the stronger flow aloft will affect parts of the Dakotas and MN late in the day when subtle height falls will commence. At the surface, a wind shift/weak front will approach the central Dakotas by late afternoon with a plume of mid to upper 60s F dewpoints spreading northward out of the central Plains ahead of the front. Strong instability will develop across this region, but capping will mitigate storm formation during much of the day. Isolated storms are possible along the front by late afternoon or early evening, aided by heating and modest low-level warm advection with 20 kt 850 mb flow. Additional nocturnal storms, likely elevated, are possible into western MN and southward along the MO River in the warm advection regime, and where instability will remain strong. Hail appears to be the main threat with this activity. Models suggest an increase in storm coverage, possibly an MCS, after 12Z Tuesday which is later than previously forecast. As such, have reduced severe probabilities for expected isolated coverage on Monday. Elsewhere, scattered storms are possible from the mid MS Valley across the OH Valley, where instability will remain strong but with rising heights aloft and weak shear. ..Jewell.. 08/17/2019 Read more

SPC 0730Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0225 AM CDT Sat Aug 17 2019 Valid 191200Z - 201200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE NORTHERN PLAINS... ...SUMMARY... Isolated severe storms are possible over parts of the northern Plains Monday evening and overnight. ...Synopsis and Discussion... A negative-tilt shortwave trough will quickly move from southern Ontario across Quebec, followed closely by another area of cyclonic flow aloft amplifying over SK and MB. The southern periphery of the stronger flow aloft will affect parts of the Dakotas and MN late in the day when subtle height falls will commence. At the surface, a wind shift/weak front will approach the central Dakotas by late afternoon with a plume of mid to upper 60s F dewpoints spreading northward out of the central Plains ahead of the front. Strong instability will develop across this region, but capping will mitigate storm formation during much of the day. Isolated storms are possible along the front by late afternoon or early evening, aided by heating and modest low-level warm advection with 20 kt 850 mb flow. Additional nocturnal storms, likely elevated, are possible into western MN and southward along the MO River in the warm advection regime, and where instability will remain strong. Hail appears to be the main threat with this activity. Models suggest an increase in storm coverage, possibly an MCS, after 12Z Tuesday which is later than previously forecast. As such, have reduced severe probabilities for expected isolated coverage on Monday. Elsewhere, scattered storms are possible from the mid MS Valley across the OH Valley, where instability will remain strong but with rising heights aloft and weak shear. ..Jewell.. 08/17/2019 Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0145 AM CDT Sat Aug 17 2019 Valid 181200Z - 191200Z ...Synopsis... Upper-level ridging begins to amplify across the western CONUS behind a shortwave trough moving over the Upper Midwest and Great Lakes tomorrow. Mid-level westerly flow of 25-50 knots will likely remain from southern Idaho into the central/northern High Plains. Once again, daytime heating will deepen the boundary layer and allow stronger winds to mix to the surface resulting in elevated to locally critical conditions (westerly sustained surface winds of 15-20 mph, RH values of 10-20%). This will be the fourth consecutive day for dry/windy conditions across the area and ERCs are now mostly between the 70th and 90th percentile. Hot/dry conditions will continue across much of the Intermountain West. ..Nauslar.. 08/17/2019 ...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 0145 AM CDT Sat Aug 17 2019 Valid 181200Z - 191200Z ...Synopsis... Upper-level ridging begins to amplify across the western CONUS behind a shortwave trough moving over the Upper Midwest and Great Lakes tomorrow. Mid-level westerly flow of 25-50 knots will likely remain from southern Idaho into the central/northern High Plains. Once again, daytime heating will deepen the boundary layer and allow stronger winds to mix to the surface resulting in elevated to locally critical conditions (westerly sustained surface winds of 15-20 mph, RH values of 10-20%). This will be the fourth consecutive day for dry/windy conditions across the area and ERCs are now mostly between the 70th and 90th percentile. Hot/dry conditions will continue across much of the Intermountain West. ..Nauslar.. 08/17/2019 ...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 0145 AM CDT Sat Aug 17 2019 Valid 181200Z - 191200Z ...Synopsis... Upper-level ridging begins to amplify across the western CONUS behind a shortwave trough moving over the Upper Midwest and Great Lakes tomorrow. Mid-level westerly flow of 25-50 knots will likely remain from southern Idaho into the central/northern High Plains. Once again, daytime heating will deepen the boundary layer and allow stronger winds to mix to the surface resulting in elevated to locally critical conditions (westerly sustained surface winds of 15-20 mph, RH values of 10-20%). This will be the fourth consecutive day for dry/windy conditions across the area and ERCs are now mostly between the 70th and 90th percentile. Hot/dry conditions will continue across much of the Intermountain West. ..Nauslar.. 08/17/2019 ...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 0145 AM CDT Sat Aug 17 2019 Valid 181200Z - 191200Z ...Synopsis... Upper-level ridging begins to amplify across the western CONUS behind a shortwave trough moving over the Upper Midwest and Great Lakes tomorrow. Mid-level westerly flow of 25-50 knots will likely remain from southern Idaho into the central/northern High Plains. Once again, daytime heating will deepen the boundary layer and allow stronger winds to mix to the surface resulting in elevated to locally critical conditions (westerly sustained surface winds of 15-20 mph, RH values of 10-20%). This will be the fourth consecutive day for dry/windy conditions across the area and ERCs are now mostly between the 70th and 90th percentile. Hot/dry conditions will continue across much of the Intermountain West. ..Nauslar.. 08/17/2019 ...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 0145 AM CDT Sat Aug 17 2019 Valid 181200Z - 191200Z ...Synopsis... Upper-level ridging begins to amplify across the western CONUS behind a shortwave trough moving over the Upper Midwest and Great Lakes tomorrow. Mid-level westerly flow of 25-50 knots will likely remain from southern Idaho into the central/northern High Plains. Once again, daytime heating will deepen the boundary layer and allow stronger winds to mix to the surface resulting in elevated to locally critical conditions (westerly sustained surface winds of 15-20 mph, RH values of 10-20%). This will be the fourth consecutive day for dry/windy conditions across the area and ERCs are now mostly between the 70th and 90th percentile. Hot/dry conditions will continue across much of the Intermountain West. ..Nauslar.. 08/17/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

WW 0589 Status Updates
STATUS REPORT ON WW 589 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 30 N DDC TO 50 W HLC TO 35 ESE MCK. ..MARSH..08/17/19 ATTN...WFO...TOP...EAX...ICT...DDC...GLD...GID...OAX... STATUS REPORT FOR WS 589 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS KSC003-005-009-013-017-027-029-031-041-043-045-051-053-059-061- 063-065-085-087-089-091-103-105-107-111-113-115-117-121-123-127- 131-135-139-141-143-147-149-157-159-161-163-165-167-169-177-179- 183-195-197-201-209-170740- KS . KANSAS COUNTIES INCLUDED ARE ANDERSON ATCHISON BARTON BROWN CHASE CLAY CLOUD COFFEY DICKINSON DONIPHAN DOUGLAS ELLIS ELLSWORTH FRANKLIN GEARY GOVE GRAHAM JACKSON JEFFERSON JEWELL JOHNSON LEAVENWORTH LINCOLN LINN LYON MCPHERSON MARION MARSHALL MIAMI MITCHELL MORRIS NEMAHA NESS OSAGE OSBORNE OTTAWA PHILLIPS POTTAWATOMIE REPUBLIC RICE RILEY ROOKS RUSH RUSSELL SALINE SHAWNEE SHERIDAN SMITH TREGO WABAUNSEE WASHINGTON Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0139 AM CDT Sat Aug 17 2019 Valid 171200Z - 181200Z ...Synopsis... An upper-level shortwave trough will move over the northern Rockies and northern Plains with zonal upper-level flow across much of the CONUS. The dry slot will move over portions of the Intermountain West with stronger 700-500 mb flow stretching from southern Idaho into the central/northern High Plains. With daytime heating, stronger winds will likely mix to the surface resulting in elevated to locally critical conditions from the Snake River Plain through the Great Divide Basin and across portions of western/northern Colorado. Westerly winds of 15-20 mph and RH values of 10-20% are likely to develop this afternoon/evening across the area. Additionally, locally elevated conditions are possible in northern Arizona where multiple large fires are active, which produced smoke plumes seen on visible satellite imagery on Friday. Isolated dry thunderstorms are likely to develop across northwest Colorado, far northeast Utah, and far southern Wyoming this afternoon/evening. High LCLs (around 3 km), a dry sub-cloud layer, and storm motions of 30-35 knots will limit wetting rains and increase chances for lightning ignitions. There is some concern that the Cu field will not become vertically developed enough for thunderstorms due to the limited amount of moisture (forecast precipitable water values of 0.4-0.55") and instability present. Isolated dry thunderstorms may also be possible across the Caprock and Texas Rolling Plains this afternoon and evening. While wetting rains are likely, lightning ignitions on the periphery of storms have occurred recently per LUB. Given the high LCLs and forecast DCAPE of 1500+ J/kg, strong outflow winds are also possible. ..Nauslar.. 08/17/2019 ...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 0139 AM CDT Sat Aug 17 2019 Valid 171200Z - 181200Z ...Synopsis... An upper-level shortwave trough will move over the northern Rockies and northern Plains with zonal upper-level flow across much of the CONUS. The dry slot will move over portions of the Intermountain West with stronger 700-500 mb flow stretching from southern Idaho into the central/northern High Plains. With daytime heating, stronger winds will likely mix to the surface resulting in elevated to locally critical conditions from the Snake River Plain through the Great Divide Basin and across portions of western/northern Colorado. Westerly winds of 15-20 mph and RH values of 10-20% are likely to develop this afternoon/evening across the area. Additionally, locally elevated conditions are possible in northern Arizona where multiple large fires are active, which produced smoke plumes seen on visible satellite imagery on Friday. Isolated dry thunderstorms are likely to develop across northwest Colorado, far northeast Utah, and far southern Wyoming this afternoon/evening. High LCLs (around 3 km), a dry sub-cloud layer, and storm motions of 30-35 knots will limit wetting rains and increase chances for lightning ignitions. There is some concern that the Cu field will not become vertically developed enough for thunderstorms due to the limited amount of moisture (forecast precipitable water values of 0.4-0.55") and instability present. Isolated dry thunderstorms may also be possible across the Caprock and Texas Rolling Plains this afternoon and evening. While wetting rains are likely, lightning ignitions on the periphery of storms have occurred recently per LUB. Given the high LCLs and forecast DCAPE of 1500+ J/kg, strong outflow winds are also possible. ..Nauslar.. 08/17/2019 ...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 0139 AM CDT Sat Aug 17 2019 Valid 171200Z - 181200Z ...Synopsis... An upper-level shortwave trough will move over the northern Rockies and northern Plains with zonal upper-level flow across much of the CONUS. The dry slot will move over portions of the Intermountain West with stronger 700-500 mb flow stretching from southern Idaho into the central/northern High Plains. With daytime heating, stronger winds will likely mix to the surface resulting in elevated to locally critical conditions from the Snake River Plain through the Great Divide Basin and across portions of western/northern Colorado. Westerly winds of 15-20 mph and RH values of 10-20% are likely to develop this afternoon/evening across the area. Additionally, locally elevated conditions are possible in northern Arizona where multiple large fires are active, which produced smoke plumes seen on visible satellite imagery on Friday. Isolated dry thunderstorms are likely to develop across northwest Colorado, far northeast Utah, and far southern Wyoming this afternoon/evening. High LCLs (around 3 km), a dry sub-cloud layer, and storm motions of 30-35 knots will limit wetting rains and increase chances for lightning ignitions. There is some concern that the Cu field will not become vertically developed enough for thunderstorms due to the limited amount of moisture (forecast precipitable water values of 0.4-0.55") and instability present. Isolated dry thunderstorms may also be possible across the Caprock and Texas Rolling Plains this afternoon and evening. While wetting rains are likely, lightning ignitions on the periphery of storms have occurred recently per LUB. Given the high LCLs and forecast DCAPE of 1500+ J/kg, strong outflow winds are also possible. ..Nauslar.. 08/17/2019 ...Please see www.spc.noaa.gov/fire for graphic product... Read more