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SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1128 AM CST Sun Feb 19 2023 Valid 201200Z - 211200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous United States on Monday. ...Discussion... Broad cyclonic flow aloft will continue to prevail across the entire U.S. Monday, as a deep polar vortex remains over northern portions of Hudson Bay through the period. Meanwhile, a separate/closed low -- progged to lie just off the southern California/northern Baja coast early -- is expected to drift eastward/southeastward through the period. As this low moves eastward, modest cooling aloft may combine with daytime heating to allow minimal CAPE development over portions of Arizona. Given this, associated ascent may be sufficient to support development of showers and possibly a thunderstorm or two during the afternoon Elsewhere, a disturbance within the broad cyclonic flow field aloft is progged to cross the Upper Midwest and later the Upper Great Lakes/Ohio Valley. QG ascent associated with the southern fringe of this feature may prove sufficient to allow isolated/elevated convective development across portions of the Middle/Lower Mississippi and Tennessee Valleys and vicinity, where some lightning potential remains evident. Elsewhere, thunderstorms are not expected. ..Goss.. 02/19/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1018 AM CST Sun Feb 19 2023 Valid 191630Z - 201200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected through tonight. ...Discussion... Conditions will remain unfavorable for thunderstorms. A few showers may develop across south Florida and/or near the Atlantic coast later today, but deeper convection capable of lightning is unlikely. ..Guyer/Weinman.. 02/19/2023 Read more

Flows from Iron Gate Dam into the Klamath River were reduced by about 11%, according to the Bureau of Reclamation, as years of drought affect water supplies in the region. Water flows will be managed through April 1, while seeking technical input received through weekly Tribal Nation and stakeholder meetings. KATU-TV ABC 2 Portland (Ore.), Feb 15, 2023

No watches are valid as of Sat Feb 18 20:52:02 UTC 2023.

No Mesoscale Discussions are in effect as of Sat Feb 18 20:52:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0146 PM CST Sat Feb 18 2023 Valid 182000Z - 191200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast through early Sunday. ...20z Update... No changes needed. ..Guyer.. 02/18/2023 .PREV DISCUSSION... /ISSUED 1009 AM CST Sat Feb 18 2023/ ...Discussion... Relatively dry/stable conditions will preclude thunderstorms across the CONUS. Some convection may occur in vicinity of the Florida Straits near a stalling front, but that convection should tend to remain shallow with limited lightning flash potential. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0126 PM CST Sat Feb 18 2023 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... The previous forecast remains on track. Drier and more deeply mixed model solutions continue to hint at the potential for elevated wind/RH conditions across portions of southeast CO into adjacent areas of KS, OK, TX, and NM. Although the snow pack across southeast CO continues to erode, parcel trajectories emanating from this region may see muted diurnal RH reductions. This idea is supported by a low probability for elevated conditions in recent ensemble guidance across much of the central High Plains. Localized elevated conditions remain possible on the periphery of the snow pack and further south across eastern NM, the TX Panhandle and into western OK where low-level trajectories will likely emanate out of central NM (though extensive cloud cover remains a limiting factor for afternoon RH minimums). ..Moore.. 02/18/2023 .PREV DISCUSSION... /ISSUED 0135 AM CST Sat Feb 18 2023/ ...Synopsis... Moderate zonal flow aloft will develop across parts of the central and southern Rockies on Sunday. Off the southern California coast, a cut-off low will edge closer to the Baja Peninsula. At the surface, a cold front will sag southward into the southern Plains through the day. For most of the day, the pressure gradient will be modest. A subtle shortwave trough moving into the central Rockies later in the period will help to deepen a surface low in the High Plains. Models show large variability in terms of afternoon RH reductions from West Texas into western Oklahoma/Kansas. However, it is probable that at least a narrow band of RH around 20% will develop as westerly downslope winds increase in the vicinity of the boundary. Fuels will likely be somewhat drier in many locations given the dry and windy conditions on Saturday. Winds, however, are not expected to be overly strong and may only reach 15-20 mph. Farther south, in the Texas Panhandle/South Plains, similar winds are expected, but higher RH will occur as well due to greater cloud cover. At this time, elevated fire weather concerns appear as though they will be localized. ...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 1112 AM CST Sat Feb 18 2023 Valid 191200Z - 201200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast across the contiguous United States on Sunday. ...Synopsis... Fast, zonal mid/upper-level flow will spread across the southern tier of the U.S. as a midlevel upper trough develops eastward from the northern Rockies toward the Midwest. Surface high pressure over the Southeast will maintain a mostly dry boundary-layer. By the end of the period, weak surface troughing over the High Plains will result in some modest moistening on southerly low-level return flow across coastal and eastern TX. However, little instability, and weak forcing for ascent, will preclude thunderstorm development. ..Leitman.. 02/18/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1009 AM CST Sat Feb 18 2023 Valid 181630Z - 191200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast through early Sunday. ...Discussion... Relatively dry/stable conditions will preclude thunderstorms across the CONUS. Some convection may occur in vicinity of the Florida Straits near a stalling front, but that convection should tend to remain shallow with limited lightning flash potential. ..Guyer/Weinman.. 02/18/2023 Read more

No watches are valid as of Fri Feb 17 19:53:02 UTC 2023.

No Mesoscale Discussions are in effect as of Fri Feb 17 19:53:02 UTC 2023.

SPC 2000Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0138 PM CST Fri Feb 17 2023 Valid 172000Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous U.S. today. ...20z Update... The 10 percent general thunderstorm area as been trimmed across GA and portions of north FL with the 20z update based on current location of the surface cold front. A few lightning flashes will remain possible across parts of north Florida into coastal North Carolina as the front shifts eastward through early evening. ..Leitman.. 02/17/2023 .PREV DISCUSSION... /ISSUED 1011 AM CST Fri Feb 17 2023/ ...Discussion... A positive-tilt upper trough, extending from the lower Great Lakes and Ohio Valley to the Mid-South, will continue eastward and reach the western Atlantic late tonight and early Saturday. Although subsidence inversions/weak lapse rates were commonly noted in warm sector 12z observed soundings, a low potential for a few thunderstorms will persist today across eastern North Carolina and north Florida/southern Georgia near and ahead of a cold front. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0118 PM CST Fri Feb 17 2023 Valid 181200Z - 191200Z The Elevated area for fire weather conditions tomorrow (Saturday) has been expanded northeastward into portions of NW OK and central KS. While some guidance continues to depict minimum relative humidities around 20%, recent RAP/HRRR runs suggests that minima around 10-15% may materialize in the Elevated area. Despite these models' overmixing tendencies, this scenario appears plausible given the ejection of a subtle mid-level speed max and associated 20-30 mph surface winds. The expanded area encompasses the region where this flow will overspread ERCs around the 70th percentile (south of the current snowpack). Critical fire weather conditions are possible -- perhaps along the northern portion of the Elevated area -- but confidence in this scenario is low given model spread in minimum relative humidity forecasts, uncertainty regarding the impact of the melting snowpack on fuel dryness, and the possibility for broken mid-/upper-level clouds through the morning. ..Flournoy/Moore.. 02/17/2023 .PREV DISCUSSION... /ISSUED 0118 AM CST Fri Feb 17 2023/ ...Synopsis... A cut-off low pressure system aloft will move slowly eastward toward the Baja Peninsula on Saturday. A shortwave trough is expected to move into parts of West Texas. This feature will promote some deepening of a lee trough in the southern High Plains. With a surface high in the Southeast maintaining intensity, southwesterly winds should increase from the southern High Plains into parts of the central Plains. Recent precipitation and cooler temperatures have kept fuel moisture above critical thresholds in most of these areas. Marginally drier fuels can be expected in parts of the Texas Panhandle. Winds of 15-25 mph are possible. RH, along with fuels, will be on the marginal side. Reductions to around 20% are possible by the afternoon. Low-end elevated fire weather concerns may develop where lower RH can overlap gusty winds. ...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 1108 AM CST Fri Feb 17 2023 Valid 181200Z - 191200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast over the contiguous United States on Saturday. ...Synopsis... Quiescent weather conditions are expected on Saturday. Low-amplitude midlevel shortwave perturbations will migrate west to east across central portions of the U.S. However, strong surface high pressure centered over the southern states and Gulf Coast vicinity will result in a dry airmass unfavorable for thunderstorm development. ..Leitman.. 02/17/2023 Read more

SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1011 AM CST Fri Feb 17 2023 Valid 171630Z - 181200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Severe thunderstorms are not forecast across the contiguous U.S. today. ...Discussion... A positive-tilt upper trough, extending from the lower Great Lakes and Ohio Valley to the Mid-South, will continue eastward and reach the western Atlantic late tonight and early Saturday. Although subsidence inversions/weak lapse rates were commonly noted in warm sector 12z observed soundings, a low potential for a few thunderstorms will persist today across eastern North Carolina and north Florida/southern Georgia near and ahead of a cold front. ..Guyer/Weinman.. 02/17/2023 Read more

MD 0167 CONCERNING TORNADO WATCH 38...40... FOR PORTIONS OF SOUTH-CENTRAL AND SOUTHEASTERN MISSISSIPPI...INTO WESTERN ALABAMA
Mesoscale Discussion 0167 NWS Storm Prediction Center Norman OK 0220 PM CST Thu Feb 16 2023 Areas affected...portions of south-central and southeastern Mississippi...into western Alabama Concerning...Tornado Watch 38...40... Valid 162020Z - 162115Z The severe weather threat for Tornado Watch 38, 40 continues. SUMMARY...The tornado threat continues and may intensify over the next 1-2 hours across portions of southern MS into western AL. DISCUSSION...As of 2015 UTC, hi-res radar imagery showed a loose cluster of supercells becoming better organized across Jasper, Jefferson Davis, Marion and Walthal counties, MS. Area VADs have shown consistently strong low-level wind profiles with 0-1km bulk shear around 25-30 kt. As these supercells have matured, low-level mesocyclones have trended stronger, suggesting tornado potential is increasing. This is further corroborated by a recent report of a tornado in Smith County, MS. A corridor of enhanced tornado potential may evolve over the next hour or two as supercells continue to track northeastward and reach maturity within the strongly sheared airmass. ..Lyons.. 02/16/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...BMX...MOB...JAN...LIX... LAT...LON 31159064 32068946 32558868 32718809 32328780 31238834 31128862 31078927 31049033 31159064 Read more

MD 0166 CONCERNING TORNADO WATCH 39... FOR THE TENNESSEE VALLEY AREA
Mesoscale Discussion 0166 NWS Storm Prediction Center Norman OK 0202 PM CST Thu Feb 16 2023 Areas affected...the Tennessee Valley area Concerning...Tornado Watch 39... Valid 162002Z - 162200Z The severe weather threat for Tornado Watch 39 continues. SUMMARY...Severe potential -- including local tornado risk -- is evident across WW 39. DISCUSSION...Latest radar loop shows that storms have increased in intensity across the area, coincident with gradual/modest destabilization -- indicated by RAP-based objective analysis and confirmed by 18Z BNA RAOB revealing roughly 300 J/kg mixed-layer CAPE. While instability remains modest, very strong shear is indicated, with low-level south-southwesterly flow veering rapidly and increasing to 55 kt at roughly 1.5km per the BNA RAOB, resulting in intense low-level shear. Within the past hour, storms seem to have responded to the increasingly favorable overall environment, with rotating storms now indicated over eastern Humphreys County Tennessee (which will move into Dickson County shortly), and across McNairy County Tennessee and adjacent Tippah and Alcorn Counties in Mississippi. Expect severe weather potential -- including accompanying tornado risk -- to continue over the next couple of hours. ..Goss.. 02/16/2023 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LMK...OHX...BMX...HUN...MEG...JAN... LAT...LON 33848978 35838829 36658675 37098596 36898526 36338500 34378669 33698854 33848978 Read more

WW 0040 Status Updates
STATUS REPORT ON WW 32 SEVERE WEATHER THREAT CONTINUES RIGHT OF A LINE FROM 40 E 7R4 TO 60 NNW PIB TO 30 SSW GWO. ..SMITH..02/09/23 ATTN...WFO...LCH...LIX...JAN... STATUS REPORT FOR WT 32 SEVERE WEATHER THREAT CONTINUES FOR THE FOLLOWING AREAS LAC005-007-063-091-093-095-101-103-105-117-090440- LA . LOUISIANA PARISHES INCLUDED ARE ASCENSION ASSUMPTION LIVINGSTON ST. HELENA ST. JAMES ST. JOHN THE BAPTIST ST. MARY ST. TAMMANY TANGIPAHOA WASHINGTON MSC007-015-031-035-043-051-061-065-067-073-077-079-083-089-091- 097-099-101-109-113-121-123-127-129-147-163-090440- MS . MISSISSIPPI COUNTIES INCLUDED ARE ATTALA CARROLL COVINGTON FORREST GRENADA HOLMES JASPER JEFFERSON DAVIS JONES LAMAR LAWRENCE LEAKE LEFLORE MADISON MARION MONTGOMERY NESHOBA NEWTON PEARL RIVER PIKE RANKIN SCOTT SIMPSON SMITH Read more

WW 40 TORNADO AL MS 161950Z - 170200Z
URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 40 NWS Storm Prediction Center Norman OK 150 PM CST Thu Feb 16 2023 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Central and southwest Alabama Extreme southeast Mississippi * Effective this Thursday afternoon and evening from 150 PM until 800 PM CST. * Primary threats include... A few tornadoes likely with a couple intense tornadoes possible Scattered damaging wind gusts to 70 mph possible Isolated large hail events to 1 inch in diameter possible SUMMARY...Scattered supercells will spread northeastward from Mississippi into Alabama through the remainder of the afternoon/evening, and additional storm development will be possible into central/southwest Alabama. The storm environment will favor a threat for tornadoes, a couple of which could be strong, along with damaging gusts of 60-70 mph and isolated large hail near 1 inch in diameter. The tornado watch area is approximately along and 60 statute miles east and west of a line from 55 miles north northwest of Birmingham AL to 75 miles south southeast of Meridian MS. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU0). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and 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. && OTHER WATCH INFORMATION...CONTINUE...WW 38...WW 39... AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 1 inch. Extreme turbulence and surface wind gusts to 60 knots. A few cumulonimbi with maximum tops to 500. Mean storm motion vector 24035. ...Thompson Read more