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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1140 AM CST Sat Feb 25 2023 Valid 261200Z - 271200Z ...THERE IS A MODERATE RISK OF SEVERE THUNDERSTORMS OVER WESTERN OKLAHOMA... ...SUMMARY... Significant damaging wind and a few tornadoes are expected from the eastern Texas Panhandle during the late afternoon across much of Oklahoma through the evening, with a wind threat persisting into Missouri overnight. Widespread wind damage is possible. ...Synopsis... A potent shortwave trough with midlevel speed max over 120 kt will move quickly across AZ and NM during day and into western TX, KS and OK during the late afternoon and evening. This wave will take on a negative tilt after 00Z as it continues across MO and into western IL by 12Z Monday. A tight midlevel temperature gradient will exist with this system, resulting in rapid height falls. At the surface, a low will develop from eastern CO into western KS during the afternoon, and will continue to deepen as it pivots into northern MO and southern IA through Monday morning. A cold front will extend south from the low and move rapidly east through the period, as southerly winds over the warm sector bring low-level moisture north. Extreme shear profiles coupled with returning moisture and strong lift will likely result in a corridor of particularly damaging winds. ...TX/OK/KS... Warm/moist advection will be underway on Sunday with a relatively cool/capped air mass in place early. As the system rapidly approaches, prolonged mixing with strong southerly winds should result in a corridor of SBCAPE of 500-1000 J/kg, from northwest TX into the TX Panhandle and western OK by 00Z. Heating over western areas will remove the cap, and late afternoon storms are expected over TX. These will likely be supercells capable of hail and a few tornadoes, with tornado strength dependent on degree of moisture return/potential for 60s F dewpoints. A strong tornado may occur prior to the expected upscale growth to a linear MCS along the cold front. As the line of storms develops into western OK, extreme shear should aid damaging wind potential, and a few tornadoes will remain possible within the line. Effective SRH value over 500 m2/s2 are likely, perhaps up to 750 m2/s2 during the evening as the low-level jet increases to over 70 kt. The most favorable corridor of damage is expected to be along and north of the tight midlevel temperature gradient, which will also travel along the northern portion of the warm sector/better moisture. Strong lift will easily remove the cap along the cold front, with winds behind this line becoming westerly. Further supporting significant wind damage potential will be the rare nocturnal boundary-layer mixing and 850 mb winds of 60 kt out of the west. ...MO/IL... A mature line of severe storms is expected to move coincident with the midlevel vort max as it moves out of OK and KS, and proceeds into the MO/Mid MS Valley overnight. Forecast soundings indicate weak instability, but extreme wind fields will exist. Further, an area of steep lapse rates will accompany this system, further increasing the probability of strong winds aloft mixing to the surface. As such, have expanded the Marginal and Slight Risk areas into MO and IL. ..Jewell.. 02/25/2023 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1039 AM CST Sat Feb 25 2023 Valid 251700Z - 261200Z ...NO CRITICAL AREAS... Overall the previous forecast remains on track. Localized dry and breezy conditions will be possible for a few hours across portions of northeastern NM and the TX Panhandle this afternoon. However, poorly receptive fuels and limited overlap of dry and windy conditions should keep fire-weather concerns low. See the previous discussion for additional information. ..Lyons.. 02/25/2023 .PREV DISCUSSION... /ISSUED 1221 AM CST Sat Feb 25 2023/ ...Synopsis... Upper ridging will amplify some across the southern Plains as a mid-level trough approaches from the west today, encouraging surface low development across the southern High Plains, with some westerly downslope component of flow. Modestly dry and breezy conditions may develop by afternoon peak heating across northeastern New Mexico into extreme southeast Colorado and the western Oklahoma and Texas Panhandle areas. However, surface winds and RH should not meet Elevated/Critical criteria on a widespread or longer-term basis, precluding fire weather highlights this outlook. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1027 AM CST Sat Feb 25 2023 Valid 251630Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms will be possible over parts of the Tennessee Valley to southwestern Virginia, along the coast of southern California, and from northeast Oklahoma and southeastern Kansas into the Ozarks. ...Synopsis and Discussion... Deep upper low continues to progress southward off the southern CA coast. This progression is expected to trend more eastward with time, bringing the upper low across southern CA later tonight and into southern NV by early tomorrow morning. Robust wind fields will persist within the southern periphery of this system, with 100+ kt at 500-mb noted throughout the period. Strong forcing for ascent and cold mid-level temperatures will accompany this system, contributing to the potential for thunderstorms across southern CA both within the more banded convection ahead of the low and the more cellular convection at it moves overhead. Farther east, subtropical ridging centered over the FL Keys is expected to persist, with moderate mid-level flow between this ridge, the upper low farther west, and upper troughing farther north. A robust jet streak exists from the Mid MS Valley into the Northeast within this confluent westerly flow aloft. Broad ascent within the right entrance region of this jet will contribute to showers and isolated thunderstorms across the TN Valley and Mid-South this afternoon. Additional isolated thunderstorms are possible later tonight into tomorrow morning across eastern OK amid the strengthening warm-air advection and modest elevated buoyancy. ..Mosier/Thornton.. 02/25/2023 Read more

No watches are valid as of Fri Feb 24 20:14:01 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0155 PM CST Fri Feb 24 2023 Valid 242000Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF COASTAL SOUTHERN CALIFORNIA... ...SUMMARY... Locally damaging wind gusts and/or a brief tornado are possible over parts of coastal southern California today. ...Discussion... No changes are being included in the current outlook. While any risk for severe weather in coastal southern California is very limited at this point, a very weakly rotating storm or two have been observed offshore over the past hours -- though weakening as they approach the coast. Still, a stronger wind gust or very brief/weak tornado cannot be ruled out this afternoon. ..Goss.. 02/24/2023 .PREV DISCUSSION... /ISSUED 1029 AM CST Fri Feb 24 2023/ ...Synopsis... A deep upper low continues to drop southward off the CA coast. This gradual southward progression is forecast to persist throughout much of the period, before pivoting more southeastward early tomorrow morning. This progression is expected to result in the low being centered about 100-120 mi off the central CA coast by 12Z Saturday. Strong westerly/southwesterly flow currently stretches from central/southern CA across the central Plains and through the Great Lakes and Northeast. This flow is expected to trend more zonal east of the Rockies throughout the day, as ridging builds across most of the western CONUS ahead of the upper low. Additionally, subtropical ridging centered over south FL/Bahamas should persist throughout period while gradually drifting westward. A cold front extends from far southern NC west-southwestward across central portions of GA, AL, and MS. Modest warm-air advection and weak low-level convergence will contribute to showers and isolated thunderstorms north of the front from this morning into the early afternoon. Some additional storms are possible near the front across GA and southern SC this afternoon/evening. ...Coastal Southern CA... Lightning was observed about an hour ago within a deeper convective core over northern coastal Santa Barbara County CA. Sporadic lightning flashes will remain possible this morning into the afternoon, mainly over coastal portions of Santa Barbara and Ventura Counties ahead of the primary frontal band. VTX VAD profiles continue to sample low-level veering with height that supports rotation within any more robust, long-lived updrafts. As mentioned in recently issued MCD #197, these low-topped storms ahead of and eventually along a cold front may produce locally damaging gusts, waterspout or a brief tornado. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1239 PM CST Fri Feb 24 2023 Valid 251200Z - 261200Z ...NO CRITICAL AREAS... The previous discussion is on track. Diurnal mixing may create locally elevated fire weather risk Saturday afternoon across parts of southeast Colorado, northeast New Mexico, the western Oklahoma Panhandle and the northwestern Texas Panhandle. Because of limited spatial scope of the risk and marginal fuel dryness, an Elevated area is unnecessary at this time. ..Supinie.. 02/24/2023 .PREV DISCUSSION... /ISSUED 1051 PM CST Thu Feb 23 2023/ ...Synopsis... Upper ridging will continue to amplify across the Plains states as a mid-level trough approaches from the west and overspreads the Lower Colorado River Basin Saturday. Modest surface lee troughing should occur across the southern High Plains during the afternoon, promoting occasional bouts of locally Elevated dry and breezy conditions, especially near the Colorado/New Mexico/Texas and Oklahoma Panhandle borders. Similar to Day 1, the localized nature of the Elevated conditions and mediocre fuel receptiveness suggests that Elevated highlights are not currently warranted. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0188 CONCERNING BLIZZARD FOR INTERIOR SANTA BARBRA COUNTY INTERIOR MOUNTAINS...LOS ANGELES COUNTY MOUNTAINS...AND VENTURA COUNTY MOUNTAINS
Mesoscale Discussion 0188 NWS Storm Prediction Center Norman OK 1205 PM CST Fri Feb 24 2023 Areas affected...Interior Santa Barbra County Interior Mountains...Los Angeles County Mountains...and Ventura County Mountains Concerning...Blizzard Valid 241805Z - 242200Z SUMMARY...Heavy snowfall with rates exceeding 2 in/hr possible through the afternoon and evening. Blizzard conditions possible at times with near zero visibility. DISCUSSION...A low currently located off the coast of California continues to bring increasing mid-level moisture inland across Southern California across the axis of a strong 40 kt low-level jet. As the upper-level low advances eastward through the afternoon and evening, colder air will overspread the region with lapse rates steepening to around 6-6.5 C/km ahead of the frontal band. With destabilization and increasing frontal forcing, expect an increase in snowfall rates across the Santa Barbra Interior Mountains, Los Angeles County, and Ventura County Mountains through the afternoon and evening, with snowfall rates exceeding 2"/hr across the mountain passes. Sustained winds of 30-40 mph with gusts 55-70 mph (locally higher) will allow for blowing snow and reduced visibility. Blizzard conditions will be possible, with near white-out conditions and dangerous travel likely. ..Thornton/Mosier.. 02/24/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...SGX...HNX...LOX... LAT...LON 34881993 35031972 34971950 34931920 34811878 34501791 34491744 34431730 34121743 34071764 34181805 34321832 34481873 34491916 34541951 34721985 34881993 Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1108 AM CST Fri Feb 24 2023 Valid 251200Z - 261200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms will be possible along the coast of southern California Saturday into Saturday night. No severe weather is expected. ...Discussion... Relatively flat/featureless flow aloft will prevail across the eastern half of the U.S. this period, while in the West, a deep upper low -- initially off the California coast -- is forecast to advance east-southeastward into southern California/southern Nevada through the period. At the surface, a low associated with the upper system is forecast to shift across the Great Basin with time, while a trailing cold front traverses southern California and then Arizona/southern Utah. Given cold air/steep lapse rates aloft associated with the upper low, very weak CAPE will persist across parts of coastal southern California and vicinity. As a result showers will persist across the area, as well as some lightning -- possibly with a frontal convective band early, but then later with post-frontal cold-core-type convection. Lack of ample instability should preclude any appreciable severe risk. Elsewhere, with surface high pressure prevailing east of the Rockies, thunderstorms are not expected over the remainder of the U.S. through Sunday morning. ..Goss.. 02/24/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Fri Feb 24 2023 Valid 241630Z - 251200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS COASTAL SOUTHERN CALIFORNIA... ...SUMMARY... Locally damaging wind gusts and/or a brief tornado are possible over parts of coastal southern California today. ...Synopsis... A deep upper low continues to drop southward off the CA coast. This gradual southward progression is forecast to persist throughout much of the period, before pivoting more southeastward early tomorrow morning. This progression is expected to result in the low being centered about 100-120 mi off the central CA coast by 12Z Saturday. Strong westerly/southwesterly flow currently stretches from central/southern CA across the central Plains and through the Great Lakes and Northeast. This flow is expected to trend more zonal east of the Rockies throughout the day, as ridging builds across most of the western CONUS ahead of the upper low. Additionally, subtropical ridging centered over south FL/Bahamas should persist throughout period while gradually drifting westward. A cold front extends from far southern NC west-southwestward across central portions of GA, AL, and MS. Modest warm-air advection and weak low-level convergence will contribute to showers and isolated thunderstorms north of the front from this morning into the early afternoon. Some additional storms are possible near the front across GA and southern SC this afternoon/evening. ...Coastal Southern CA... Lightning was observed about an hour ago within a deeper convective core over northern coastal Santa Barbara County CA. Sporadic lightning flashes will remain possible this morning into the afternoon, mainly over coastal portions of Santa Barbara and Ventura Counties ahead of the primary frontal band. VTX VAD profiles continue to sample low-level veering with height that supports rotation within any more robust, long-lived updrafts. As mentioned in recently issued MCD #197, these low-topped storms ahead of and eventually along a cold front may produce locally damaging gusts, waterspout or a brief tornado. ..Mosier/Thornton.. 02/24/2023 Read more

The Central Texas Groundwater Conservation District opted to remain in drought Stage 4, the most severe, in Burnet County during the Board of Directors regular meeting on Feb. 17. Although the county has seen slight increases in soil moisture, groundwater is still at historic drought levels. Well level typically rebound during the winter when there is less pumping, but they haven’t rebounded much. Stage 4 of the district’s drought management plan recommends 30 percent voluntary water use reductions for county residents, no outdoor watering, no filling of pools or reservoirs, no washing of sidewalks, no water for dust control, and leak-proof livestock troughs. In December, mandatory 15% water restrictions were enacted for permitted users, due to alarmingly low groundwater levels. DailyTrib.com (Marble Falls, Texas), Feb 21, 2023

Marin Municipal Water District adopted a new plan that will trigger water conservation measures and usage restrictions earlier and more often. The district Board of Directors voted unanimously to adopt the new conservation triggers on Feb. 21. The plan will enact either mandatory or voluntary conservation measures and potential drought surcharges on rates based on reservoir storage levels as of April 1 of each year. The plan also has a drought surcharge component that would take effect when reservoir levels fall below 65,000 acre-feet. Marin Independent Journal (Calif.), Feb 22, 2023

No watches are valid as of Thu Feb 23 20:33:02 UTC 2023.

No watches are valid as of Thu Feb 23 20:33:02 UTC 2023.

No Mesoscale Discussions are in effect as of Thu Feb 23 20:33:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CST Thu Feb 23 2023 Valid 232000Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...20Z Update... Overall forecast outlined in the previous discussion (appended below) remain valid. Isolated thunderstorms are still expected across portions of the Tennessee Valley and southern Appalachians this afternoon and evening. Isolated lightning flashes also remain possible from southwest Oregon southward into southern CA. Highest coverage is currently expected early tomorrow morning along the central CA coast as the primary frontal band associated with the upper low moves over the region. ..Mosier.. 02/23/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Thu Feb 23 2023/ ...Tennessee Valley/Southern Appalachians... Weak height rises are expected regionally through tonight. Weak but persistent warm/moist advection may influence thunderstorms across the Tennessee Valley toward the southern Appalachians, with a few thunderstorms also possible in the more immediate vicinity of an east/southeastward-advancing cold front moving into/across western portions of Tennessee and Kentucky, where thermodynamic profiles are marginally supportive of lightning flashes today. While deep-layer shear and weak buoyancy would be conditionally favorable, diminishing low-level shear combined with the nebulous forcing for ascent and relatively warm/dry mid-levels suggest the threat of severe thunderstorms is low. ...Coastal Central/Southern California... Primary vort max off the Washington/Oregon coast, embedded within the deep western CONUS upper trough, should gradually move south to just off the northern California coast through 12Z Friday. While surface dew points will be initially low from the 30s to low 40s F, an increase into the mid 40s is possible near the coast by early Friday. This combined with strengthening low-level winds may be sufficient for a few weakly rotating cells and locally strong convective gusts from low-topped convection near the end of the period. However, organized severe storms currently appear unlikely. Read more

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CST Thu Feb 23 2023 Valid 232000Z - 241200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast through tonight. ...20Z Update... Overall forecast outlined in the previous discussion (appended below) remain valid. Isolated thunderstorms are still expected across portions of the Tennessee Valley and southern Appalachians this afternoon and evening. Isolated lightning flashes also remain possible from southwest Oregon southward into southern CA. Highest coverage is currently expected early tomorrow morning along the central CA coast as the primary frontal band associated with the upper low moves over the region. ..Mosier.. 02/23/2023 .PREV DISCUSSION... /ISSUED 1030 AM CST Thu Feb 23 2023/ ...Tennessee Valley/Southern Appalachians... Weak height rises are expected regionally through tonight. Weak but persistent warm/moist advection may influence thunderstorms across the Tennessee Valley toward the southern Appalachians, with a few thunderstorms also possible in the more immediate vicinity of an east/southeastward-advancing cold front moving into/across western portions of Tennessee and Kentucky, where thermodynamic profiles are marginally supportive of lightning flashes today. While deep-layer shear and weak buoyancy would be conditionally favorable, diminishing low-level shear combined with the nebulous forcing for ascent and relatively warm/dry mid-levels suggest the threat of severe thunderstorms is low. ...Coastal Central/Southern California... Primary vort max off the Washington/Oregon coast, embedded within the deep western CONUS upper trough, should gradually move south to just off the northern California coast through 12Z Friday. While surface dew points will be initially low from the 30s to low 40s F, an increase into the mid 40s is possible near the coast by early Friday. This combined with strengthening low-level winds may be sufficient for a few weakly rotating cells and locally strong convective gusts from low-topped convection near the end of the period. However, organized severe storms currently appear unlikely. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1241 PM CST Thu Feb 23 2023 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... The previous forecast is on track. Brief, localized areas of elevated fire risk are possible in eastern New Mexico on Friday afternoon. No changes are needed. ..Supinie.. 02/23/2023 .PREV DISCUSSION... /ISSUED 1257 AM CST Thu Feb 23 2023/ ...Synopsis... The upper-level trough along the West Coast will continue to dig southward on Friday. As this occurs, the trough is expected to intensify. Downstream ridging will develop ahead of the trough in the Southwest and Southern Plains. At the surface, cold air will remain up against the southern Rockies. A very limited region of dry and breezy conditions is possible in eastern New Mexico. These conditions will generally be brief and fuels will not be particularly receptive. Fire weather concerns across the CONUS will be low. ...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 1241 PM CST Thu Feb 23 2023 Valid 241200Z - 251200Z ...NO CRITICAL AREAS... The previous forecast is on track. Brief, localized areas of elevated fire risk are possible in eastern New Mexico on Friday afternoon. No changes are needed. ..Supinie.. 02/23/2023 .PREV DISCUSSION... /ISSUED 1257 AM CST Thu Feb 23 2023/ ...Synopsis... The upper-level trough along the West Coast will continue to dig southward on Friday. As this occurs, the trough is expected to intensify. Downstream ridging will develop ahead of the trough in the Southwest and Southern Plains. At the surface, cold air will remain up against the southern Rockies. A very limited region of dry and breezy conditions is possible in eastern New Mexico. These conditions will generally be brief and fuels will not be particularly receptive. Fire weather concerns across the CONUS will be low. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1114 AM CST Thu Feb 23 2023 Valid 241200Z - 251200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... A few thunderstorms may occur on Friday over parts of coastal and central California as well as southeast Georgia and southern South Carolina. ...Synopsis and Discussion... Strong westerly/southwesterly flow is forecast to stretch from central/southern CA across the central Plains and through the Great Lakes and Northeast early Friday morning. This flow is expected to trend more zonal east of the Rockies throughout the day, as ridging builds across most of the western CONUS and a strong upper low drops southward along the CA coast. Additionally, subtropical ridging initially centered over south FL/Bahamas should gradually drift westward throughout the period. At the surface, a cold front will likely extend from a low just off the ME coast southeastward through eastern NC across northern portions of the Southeast States into southeast TX. This boundary is expected to remain largely in place during the period while weakening. Showers with a few deeper cores are anticipated from northeast TX through the Mid-South into northern AL tomorrow morning, north of the cold front. A few lightning flashes are possible but modest lift coupled with warm temperatures aloft is expected to limit lightning production. A greater chance of thunderstorms exists across southeast GA/southern SC tomorrow afternoon along the front, which will be more progress here than areas farther west. Additional lightning flashes are expected within the persistent forcing for ascent and cold mid-level temperatures associated with the upper low moving southward along the CA coast. Highest coverage is expected early in the period along the coast, but an additional increase in lightning is possible during the early afternoon across southern CA as the frontal band moves through. ..Mosier.. 02/23/2023 Read more