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MD 0411 CONCERNING TORNADO WATCH 100... FOR FAR SOUTHEAST TX...SOUTHERN LA...CENTRAL/SOUTHERN MS
Mesoscale Discussion 0411 NWS Storm Prediction Center Norman OK 0535 AM CDT Wed Apr 10 2024 Areas affected...Far Southeast TX...Southern LA...Central/Southern MS Concerning...Tornado Watch 100... Valid 101035Z - 101230Z The severe weather threat for Tornado Watch 100 continues. SUMMARY...Strong wind gusts and line-embedded tornadoes remain possible across far southeast Texas and southwest Louisiana. Additionally, the tornado threat appears to be increasing across southeast Louisiana and southern Mississippi, where a Tornado Watch will be needed soon DISCUSSION...Ongoing convective line continues to move quickly across far southeast TX. Recent radar imagery has shown an increase in echo tops within the line, with a bookend vortex also becoming more observable. This line is now more favorably oriented with the deep-layer vertical shear vector and the downstream air mass remains moist and unstable. As such, the line is expected to continue progresses eastward into southwest LA, with some potential intensification possible. Primary threat remains strong gusts (60-80 mph), but embedded QLCS tornadoes are possible as well. Farther east, a blossoming warm-air advection regime is contributing to increasing storm coverage and intensity. Storm in Assumption Parish has a strong updraft with modest supercellular characteristics. This trend for increasing storm coverage and intensity will likely spread northward/northeastward into more of southeast LA and eventually into southern MS. The parameter space supports supercells capable of all severe hazards and Tornado Watch will likely be needed soon. ..Mosier/Smith.. 04/10/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...MOB...JAN...LIX...LCH...HGX... LAT...LON 29429189 29599311 29509413 29739459 30079467 30529448 30929373 31339162 32379032 32288886 31078899 29439029 29429189 Read more

WW 0100 Status Updates
STATUS REPORT ON WW 100 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ESE GLS TO 40 W POE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0411 ..MOSIER..04/10/24 ATTN...WFO...LCH... STATUS REPORT FOR WT 100 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC001-003-009-011-019-023-039-045-053-055-079-097-099-101-113- 115-101240- LA . LOUISIANA PARISHES INCLUDED ARE ACADIA ALLEN AVOYELLES BEAUREGARD CALCASIEU CAMERON EVANGELINE IBERIA JEFFERSON DAVIS LAFAYETTE RAPIDES ST. LANDRY ST. MARTIN ST. MARY VERMILION VERNON TXC351-101240- TX . TEXAS COUNTIES INCLUDED ARE NEWTON GMZ430-432-435-436-450-452-455-101240- Read more

WW 0100 Status Updates
STATUS REPORT ON WW 100 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ESE GLS TO 40 W POE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0411 ..MOSIER..04/10/24 ATTN...WFO...LCH... STATUS REPORT FOR WT 100 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC001-003-009-011-019-023-039-045-053-055-079-097-099-101-113- 115-101240- LA . LOUISIANA PARISHES INCLUDED ARE ACADIA ALLEN AVOYELLES BEAUREGARD CALCASIEU CAMERON EVANGELINE IBERIA JEFFERSON DAVIS LAFAYETTE RAPIDES ST. LANDRY ST. MARTIN ST. MARY VERMILION VERNON TXC351-101240- TX . TEXAS COUNTIES INCLUDED ARE NEWTON GMZ430-432-435-436-450-452-455-101240- Read more

MD 0410 CONCERNING SEVERE POTENTIAL...WATCH POSSIBLE FOR CENTRAL MS
Mesoscale Discussion 0410 NWS Storm Prediction Center Norman OK 0501 AM CDT Wed Apr 10 2024 Areas affected...Central MS Concerning...Severe potential...Watch possible Valid 101001Z - 101200Z Probability of Watch Issuance...40 percent SUMMARY...Isolated damaging gusts and potentially a brief tornado are possible across central Mississippi over the next few hours. DISCUSSION...Convective line stretching from northern MS southwestward through central LA has shown a bit more forward propagation over the past hour or so, as this portion of the line becomes more perpendicular to the deep-layer shear vector. The strongest updrafts within the line now exist over central MS, where a few bowing segments currently exist. Recent VAD profile from KDGX sample 220-225 m2/s2 of 0-1 km storm-relatively helicity over the past half hour, which matches well with a small maximum in 0-1 km storm-relatively helicity in the same region on the mesoanalysis. However, low-level stability persists across the region, with recent mesoanalysis and forecast soundings estimating substantial convective inhibition remains in place. Even so, a few damaging gusts may still be able to reach the surface. Additionally, any sustained mesovortex may be able to produce a brief tornado. However, the low-level stability is expected to keep the overall severe potential low, despite the favorable kinematics. ..Mosier/Smith.. 04/10/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...JAN... LAT...LON 31509122 31869092 32329031 32948998 33468978 33678928 33478878 32948883 31818928 31488964 31399023 31509122 Read more

WW 0101 Status Updates
STATUS REPORT ON WW 100 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ESE GLS TO 40 W POE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0411 ..MOSIER..04/10/24 ATTN...WFO...LCH... STATUS REPORT FOR WT 100 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC001-003-009-011-019-023-039-045-053-055-079-097-099-101-113- 115-101240- LA . LOUISIANA PARISHES INCLUDED ARE ACADIA ALLEN AVOYELLES BEAUREGARD CALCASIEU CAMERON EVANGELINE IBERIA JEFFERSON DAVIS LAFAYETTE RAPIDES ST. LANDRY ST. MARTIN ST. MARY VERMILION VERNON TXC351-101240- TX . TEXAS COUNTIES INCLUDED ARE NEWTON GMZ430-432-435-436-450-452-455-101240- Read more

WW 0101 Status Updates
STATUS REPORT ON WW 100 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 50 ESE GLS TO 40 W POE. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0411 ..MOSIER..04/10/24 ATTN...WFO...LCH... STATUS REPORT FOR WT 100 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC001-003-009-011-019-023-039-045-053-055-079-097-099-101-113- 115-101240- LA . LOUISIANA PARISHES INCLUDED ARE ACADIA ALLEN AVOYELLES BEAUREGARD CALCASIEU CAMERON EVANGELINE IBERIA JEFFERSON DAVIS LAFAYETTE RAPIDES ST. LANDRY ST. MARTIN ST. MARY VERMILION VERNON TXC351-101240- TX . TEXAS COUNTIES INCLUDED ARE NEWTON GMZ430-432-435-436-450-452-455-101240- Read more

MD 0409 CONCERNING SEVERE THUNDERSTORM WATCH 99... FOR UPPER TX COAST/SOUTHEAST TEXAS...SOUTHWEST/SOUTH-CENTRAL LOUISIANA
Mesoscale Discussion 0409 NWS Storm Prediction Center Norman OK 0321 AM CDT Wed Apr 10 2024 Areas affected...Upper TX Coast/Southeast Texas...Southwest/South-Central Louisiana Concerning...Severe Thunderstorm Watch 99... Valid 100821Z - 101015Z The severe weather threat for Severe Thunderstorm Watch 99 continues. SUMMARY...Damaging wind gusts, some of which could exceed 75 mph, and line-embedded tornadoes are expected to become more common over the next few hours. A downstream Tornado Watch will likely be needed across far southeast Texas and southwest/south-central Louisiana. DISCUSSION...Convective trends within the ongoing line across southeast TX/Upper TX Coast continue to suggest organization into a more formidable squall line is underway. Current storm motion of this line is eastward at 40 kt, and this storm motion takes it to the edge of Severe Thunderstorm Watch 99 at 10Z. However, some additional acceleration is likely as the line becomes better organized, potentially taking it to the edge of the watch sooner. An outflow boundary remains draped from northern Harris County eastward in Calcasieu Parish. Interaction with this boundary likely contributed to the mesovortex currently ongoing over northern Harris County. This boundary will likely act as the northern extent of the severe risk over the next few hours. Damaging wind gusts, some of which could exceed 75 mph, will remain the primary severe risk. However, line-embedded mesovorticies capable of tornadoes are also expected to become more common as the line moves into far southeast TX and southwest LA. As a result, a Tornado Watch will likely be needed downstream within the next hour. ..Mosier/Smith.. 04/10/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LCH...HGX... LAT...LON 30099569 30949474 31029225 30119185 29699259 29579325 29489395 29099489 28699592 30099569 Read more

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 0099 Status Updates
STATUS REPORT ON WW 99 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 ESE PSX TO 35 SSE UTS TO 15 SW UTS. FOR ADDITIONAL INFORMATION SEE MESOSCALE DISCUSSION 0409 ..MOSIER..04/10/24 ATTN...WFO...HGX... STATUS REPORT FOR WS 99 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS TXC039-071-167-291-373-407-471-101040- TX . TEXAS COUNTIES INCLUDED ARE BRAZORIA CHAMBERS GALVESTON LIBERTY POLK SAN JACINTO WALKER GMZ335-355-101040- CW . ADJACENT COASTAL WATERS INCLUDED ARE GALVESTON BAY COASTAL WATERS FROM HIGH ISLAND TO FREEPORT TX OUT 20 NM 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

WW 99 SEVERE TSTM TX CW 100450Z - 101200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 99 NWS Storm Prediction Center Norman OK 1150 PM CDT Tue Apr 9 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of Southeast Texas Coastal Waters * Effective this Tuesday night and Wednesday morning from 1150 PM until 700 AM CDT. * Primary threats include... Widespread damaging winds and isolated significant gusts to 85 mph likely Scattered large hail and isolated very large hail events to 2 inches in diameter possible A tornado or two possible SUMMARY...An intense line of thunderstorms over south Texas will track eastward overnight across the watch area. The potential exists for considerable coverage of damaging wind gust and some hail. Isolated tornadoes are also possible along the leading edge of the squall line. The severe thunderstorm watch area is approximately along and 65 statute miles east and west of a line from 65 miles north northwest of Houston TX to 30 miles southeast of Palacios TX. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU9). 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 98... AVIATION...A few severe thunderstorms with hail surface and aloft to 2 inches. Extreme turbulence and surface wind gusts to 75 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 26035. ...Hart Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Wed Apr 10 2024 Valid 131200Z - 181200Z ...DISCUSSION... Primary feature of concern will be an amplified upper low that is initially off the CA coast at 12Z Saturday. This low should dampen as it steadily progresses across the Southwest, before amplifying once again as it emerges onto the central Great Plains sometime on D6, as a separate shortwave trough digs towards the Pacific Northwest. Timing spread within the 00Z deterministic and ensemble guidance appears larger relative to yesterday, with the 00Z ECMWF decidedly trending farther east over the past 24 hours. It appears to be on the eastern envelope compared to its ensemble members. The overall forecast impact is with regard to dryline placement and surface cyclone evolution during the day on Monday and beyond. The actual severe weather setup appears substantial. Air mass modification will ensue northward from the western Gulf on D3, with multiple days to improve the low-level moisture profile amid well above-normal surface temperatures and a pronounced elevated mixed layer. With the likely flow field amplification through the troposphere, all ingredients appear present for a significant severe weather day on D6/Monday. The areal uncertainty of the synoptic features is the primary limiting factor. For now, have added a confined 30 percent highlight to indicate the higher-end potential and the most probable corridor, while broadening the previous 15 percent area. A lesser severe threat will probably continue into D7/Tuesday. But even further spatial uncertainty, in conjunction with the impact of the prior day convection and consensus signal for the deep cyclone to occlude northeastward, renders low confidence for highlighting a severe threat area yet. The area-of-interest appears to have shifted more to the east relative to yesterday, in an arc around the eastern Corn Belt to the Ark-La-Tex. Read more