SPC 1630Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1029 AM CST Tue Feb 18 2025 Valid 181630Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST TEXAS AND SOUTHERN LOUISIANA... ...SUMMARY... Isolated severe thunderstorms are possible this evening across parts of southeast Texas, shifting across southern Louisiana tonight. Hail should be the primary hazard, but a brief tornado and occasional severe gusts may occur along the immediate Louisiana Coast. ...Southeast Texas into Southern Louisiana... Water-vapor imagery this morning shows a shortwave trough moving into northern AZ from the Great Basin. This upper feature will move east-southeast during the period reaching northern LA/southern AR by daybreak Wednesday. Surface analysis this morning delineates an arctic cold front from the Concho Valley northeastward into north TX. This boundary will continue to surge south-southeastward to the TX coast tonight. A modifying airmass over the northwest Gulf Basin will aid in destabilization this afternoon/evening over southeast TX. Thunderstorms should eventually form by this evening across parts of southeast TX as large-scale ascent increases. Forecast soundings continue to indicate this thunderstorm activity will likely remain elevated with around 1000 J/kg MUCAPE. This activity will spread eastward across portions of southern LA late this evening and overnight while posing mainly an isolated hail threat. The surface-based thunderstorm probabilities are greatest near the south-central and southeast LA coast. However, low-level lapse rates in a deep/saturated environment will be modest, likely limiting tornado potential. Nonetheless, if a couple of storms can become near-surface based in the coastal parishes, a risk for severe gusts may accompany the stronger storms. ..Smith.. 02/18/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0933 AM CST Tue Feb 18 2025 Valid 181700Z - 191200Z The previous forecast remains on track with only minor adjustments needed. Morning surface observations show a strong cold front pushing south along the southern High Plains faster than anticipated by last night's model guidance. 12z guidance has captured recent trends well and suggests cold air damming along the eastern slopes of the Guadelupe and Davis mountains will limit the eastern extent of elevated fire weather conditions. 15-25 mph winds within a dry, well-mixed layer above a shallow nocturnal inversion on the 12z EPZ sounding lends confidence to the ongoing forecast. See the previous discussion for additional details. ..Moore.. 02/18/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Feb 18 2025/ ...Synopsis... The western trough will dig southward and slowly eject across the desert southwest today. Downward mixing of westerly flow aloft across southern Arizona into southern New Mexico will support potential for overlap of relative humidity reductions to 15-20 percent with sustained surface winds around 10-15 mph (gusting 20-30 mph). ERCs are near the 75th percentile, however, primarily localized Critical conditions are expected. This will preclude the need to include any Critical areas at this time. ...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 0933 AM CST Tue Feb 18 2025 Valid 181700Z - 191200Z The previous forecast remains on track with only minor adjustments needed. Morning surface observations show a strong cold front pushing south along the southern High Plains faster than anticipated by last night's model guidance. 12z guidance has captured recent trends well and suggests cold air damming along the eastern slopes of the Guadelupe and Davis mountains will limit the eastern extent of elevated fire weather conditions. 15-25 mph winds within a dry, well-mixed layer above a shallow nocturnal inversion on the 12z EPZ sounding lends confidence to the ongoing forecast. See the previous discussion for additional details. ..Moore.. 02/18/2025 .PREV DISCUSSION... /ISSUED 0142 AM CST Tue Feb 18 2025/ ...Synopsis... The western trough will dig southward and slowly eject across the desert southwest today. Downward mixing of westerly flow aloft across southern Arizona into southern New Mexico will support potential for overlap of relative humidity reductions to 15-20 percent with sustained surface winds around 10-15 mph (gusting 20-30 mph). ERCs are near the 75th percentile, however, primarily localized Critical conditions are expected. This will preclude the need to include any Critical areas at this time. ...Please see www.spc.noaa.gov/fire for graphic product... Read more

MD 0113 CONCERNING WINTER MIXED PRECIPITATION FOR PARTS OF CENTRAL/EASTERN OK INTO NORTHWEST AR AND EXTREME SOUTHWEST MO
Mesoscale Discussion 0113 NWS Storm Prediction Center Norman OK 0748 AM CST Tue Feb 18 2025 Areas affected...Parts of central/eastern OK into northwest AR and extreme southwest MO Concerning...Winter mixed precipitation Valid 181348Z - 181645Z SUMMARY...Light to locally moderate freezing rain and/or sleet is possible this morning. Increasing snow rates are possible by late morning across northeast Oklahoma and vicinity. DISCUSSION...Light precipitation is gradually increasing this morning across parts of central/eastern OK, in response to warm advection near/above 850 mb atop a southward-advancing arctic airmass. The 12Z OUN sounding depicts saturation primarily below a notable temperature inversion around 700 mb. In the short term, given the relatively shallow saturated layer and lack of deeper ascent above this layer, a period of freezing drizzle/light freezing rain will be possible, with relatively efficient ice accretion in areas where near-surface temperatures fall through the 20s F. With time, deeper/stronger ascent will result in locally heavier precipitation rates later this morning. This may be accompanied by an transition to sleet and snow (especially with northward extent), due to continued near-surface cold advection and wet-bulb cooling of the initially dry layer near 700 mb. Snow rates may begin to increase by late morning across northeast OK and vicinity, with locally heavy snow possible this afternoon. ..Dean.. 02/18/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...LZK...SGF...SHV...TSA...ICT...FWD...OUN... LAT...LON 35729755 36679734 37079643 37039450 36179406 34359354 34229401 34719468 34859503 34789559 34549622 34219700 33929779 34189828 34879786 35269768 35729755 Read more

No Mesoscale Discussions are in effect as of Tue Feb 18 12:46:02 UTC 2025.

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0630 AM CST Tue Feb 18 2025 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST TEXAS AND SOUTHERN LOUISIANA... ...SUMMARY... Isolated severe thunderstorms are possible this evening across parts of southeast Texas, shifting across southern Louisiana tonight. Hail should be the primary hazard, but a brief tornado and occasional severe gusts may occur along the immediate Louisiana Coast. ...Southeast Texas into Southern Louisiana... A mid-level shortwave trough will progress east-southeastward from the Great Basin to the southern Plains by tonight. At the surface, an arctic cold front will continue surging southward across TX through the day, eventually reaching the TX Coast by late tonight. Modest low-level moisture is forecast to advance northward along/near the middle/upper TX Coast ahead of the front. Thunderstorms should eventually form by this evening across parts of southeast TX as the shortwave trough approaches. Various NAM/RAP forecast soundings suggest this convection will likely remain elevated above a near-surface stable layer. Still, around 1000-1250 J/kg of MUCAPE aided by modestly steepened mid-level lapse rates, and strong deep-layer shear in the cloud bearing layer, may support isolated severe hail with the more robust cores. This activity will spread eastward across portions of southern LA late this evening and overnight while posing mainly a continued hail threat. There is also a low, but non-zero, chance of near-surface-based thunderstorms along the immediate LA Coast late tonight into early Wednesday morning, where somewhat greater low-level moisture should be present. If convection can become surface-based across this area, then isolated strong to severe wind gusts and perhaps a brief tornado would be possible. ..Gleason/Dean.. 02/18/2025 Read more

SPC 1300Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0630 AM CST Tue Feb 18 2025 Valid 181300Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF SOUTHEAST TEXAS AND SOUTHERN LOUISIANA... ...SUMMARY... Isolated severe thunderstorms are possible this evening across parts of southeast Texas, shifting across southern Louisiana tonight. Hail should be the primary hazard, but a brief tornado and occasional severe gusts may occur along the immediate Louisiana Coast. ...Southeast Texas into Southern Louisiana... A mid-level shortwave trough will progress east-southeastward from the Great Basin to the southern Plains by tonight. At the surface, an arctic cold front will continue surging southward across TX through the day, eventually reaching the TX Coast by late tonight. Modest low-level moisture is forecast to advance northward along/near the middle/upper TX Coast ahead of the front. Thunderstorms should eventually form by this evening across parts of southeast TX as the shortwave trough approaches. Various NAM/RAP forecast soundings suggest this convection will likely remain elevated above a near-surface stable layer. Still, around 1000-1250 J/kg of MUCAPE aided by modestly steepened mid-level lapse rates, and strong deep-layer shear in the cloud bearing layer, may support isolated severe hail with the more robust cores. This activity will spread eastward across portions of southern LA late this evening and overnight while posing mainly a continued hail threat. There is also a low, but non-zero, chance of near-surface-based thunderstorms along the immediate LA Coast late tonight into early Wednesday morning, where somewhat greater low-level moisture should be present. If convection can become surface-based across this area, then isolated strong to severe wind gusts and perhaps a brief tornado would be possible. ..Gleason/Dean.. 02/18/2025 Read more

Day 4-8 Outlook
Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0315 AM CST Tue Feb 18 2025 Valid 211200Z - 261200Z ...DISCUSSION... Dry and stable surface high pressure will persist across much of the CONUS during the Day 4-8 period. This will result in a dearth of moisture and continental trajectories preclude Gulf moisture return. By the end of the period around Day 8/Tue, an upper ridge over the western U.S. will creep east over the Plains. This may allow some modest Gulf moisture to return northward across parts of TX. Regardless, thunderstorm potential appears low this weekend into early next week. Read more

SPC Day 2 Fire Weather Outlook
Day 2 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0144 AM CST Tue Feb 18 2025 Valid 191200Z - 201200Z ...NO CRITICAL AREAS... ...Synopsis... Height rises and building high pressure across the western US and southern/central Rockies will result in lighter winds where dry conditions are expected. Across the Plains, an arctic air mass will settle in, with cool and wet conditions across much of the southern and central Plains. Less precipitation is forecast across western Texas, but light winds and higher relative humidity is expected. Overall, fire weather concerns will be minimal owing to cool conditions and lighter wind speeds where the driest conditions are expected. ..Thornton.. 02/18/2025 ...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 0142 AM CST Tue Feb 18 2025 Valid 181200Z - 191200Z ...Synopsis... The western trough will dig southward and slowly eject across the desert southwest today. Downward mixing of westerly flow aloft across southern Arizona into southern New Mexico will support potential for overlap of relative humidity reductions to 15-20 percent with sustained surface winds around 10-15 mph (gusting 20-30 mph). ERCs are near the 75th percentile, however, primarily localized Critical conditions are expected. This will preclude the need to include any Critical areas at this time. ..Thornton.. 02/18/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

SPC 0830Z Day 3 Outlook
Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0130 AM CST Tue Feb 18 2025 Valid 201200Z - 211200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not expected on Thursday. ...Synopsis... Strong surface high pressure and an Arctic airmass will settle over much of the CONUS on Thursday. A cold front will shift south over South FL, but poor lapse rates and warm temperatures aloft will preclude sufficient destabilization for thunderstorms. Elsewhere, cold and stable conditions will preclude thunderstorm activity. ..Leitman.. 02/18/2025 Read more

SPC 0700Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1222 AM CST Tue Feb 18 2025 Valid 191200Z - 201200Z ...NO SEVERE THUNDERSTORM AREAS FORECAST... ...SUMMARY... Isolated thunderstorms are possible across portions of the Southeast on Wednesday, but severe storms are not expected. ...Synopsis... A weak surface low is forecast to be near far southeast LA at the beginning of the forecast period, with a trailing Arctic cold front extending southwest into the western Gulf. Isolated thunderstorms will likely be ongoing from southeast LA eastward along the central Gulf coast vicinity during the morning. Stronger convection will remain over the warmer Gulf waters as the cold front develops east/southeast through the day. Poor lapse rates and modest boundary-layer moisture ahead of the cold front will preclude much destabilization over land. A couple of thunderstorms may develop over the FL Peninsula during the late afternoon/early evening, but severe thunderstorms are not expected given the expected poor thermodynamic environment. ..Leitman.. 02/18/2025 Read more

SPC 1200Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1140 PM CST Mon Feb 17 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS IN SOUTHEAST TX AND SOUTH LA... ...SUMMARY... Isolated severe thunderstorms are possible this evening across parts of southeast Texas, shifting across south Louisiana tonight. Large hail should be the primary hazard, but a tornado and severe gusts will be possible along the immediate Louisiana coast. ...Southeast TX and south LA... A low-amplitude shortwave trough over the eastern Great Basin will progress east and reach the Mid-MS to Lower Red River Valley by early morning Wednesday. Weak surface cyclogenesis will occur tonight over the northwest Gulf, as a baroclinic zone strengthens in its wake with a surface ridge expanding south across the southern Great Plains. The downstream surface warm front should approach coastal LA, mainly near the mouth of the MS River, struggling to displace the modified continental air mass inland. Prior to the arrival of the Arctic air mass nosing south over the Plains, Gulf air should spread across parts of the Lower to Middle TX Coast this afternoon. To the northeast of this across southeast TX, strengthening low-level warm theta-e advection should foster elevated thunderstorms by early evening. While MUCAPE should remain weak amid moderate mid-level lapse rates, favorable speed shear within a nearly unidirectional west-southwesterly wind profile will support a threat for isolated severe hail. Elevated convection will likely consolidate into a broadening cluster in the mid to late evening across southeast TX and LA, further reinforcing the stable surface air mass inland where mid-level lapse rates will also be weaker. Overnight, organization of the cluster/short-line segments should occur near the immediate LA coast. Embedded supercell structures may brush the mouth of the MS River vicinity with an attendant tornado/severe gust threat. ..Grams/Thornton.. 02/18/2025 Read more

SPC 0100Z Day 1 Outlook
Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 0630 PM CST Mon Feb 17 2025 Valid 180100Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... The risk for thunderstorms should remain negligible tonight. ...Discussion... Conditions will be too dry/stable for lightning-producing convection across much of the CONUS through the period. A lone thunderstorm occurred in the past hour over western CO amid scant buoyancy and very steep lapse rates per the 00Z GJT sounding. While an additional storm or two might occur in the next hour or so, amid moderate large-scale ascent, predominately sub-freezing thermodynamic profiles with eastern extent across the CO Rockies and adjacent High Plains should largely mitigate thunderstorm potential. ..Grams.. 02/18/2025 Read more

SPC Day 3-8 Fire Weather Outlook
Day 3-8 Fire Weather Outlook NWS Storm Prediction Center Norman OK 0355 PM CST Mon Feb 17 2025 Valid 191200Z - 251200Z The extended forecast period will begin with a very strong Arctic high pressure in the central Plains. The associated cold front will push into the High Plains with warm and dry conditions confined to portions of the Southwest. Dry fuels remain confined to southern New Mexico and vicinity where no additional precipitation is expected this week. Therefore, by the end of the week and into the weekend when dry westerly conditions resume ahead of an approaching mid-level trough, some elevated fire weather conditions may resume. Some critical fire weather conditions may be possible, but there still remains too much uncertainty regarding the strength of winds and the timing of the trough for any probabilities at this time. ..Bentley.. 02/17/2025 ...Please see www.spc.noaa.gov/fire for graphic product... Read more

No watches are valid as of Mon Feb 17 17:34:01 UTC 2025.

No Mesoscale Discussions are in effect as of Mon Feb 17 17:34:01 UTC 2025.

SPC 1730Z Day 2 Outlook
Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1127 AM CST Mon Feb 17 2025 Valid 181200Z - 191200Z ...THERE IS A MARGINAL RISK OF SEVERE THUNDERSTORMS FROM PORTIONS OF SOUTHEASTERN TEXAS EASTWARD ACROSS SOUTHERN LOUISIANA... ...SUMMARY... A couple of strong to severe thunderstorms are expected to evolve across southeast Texas and portions of southern Louisiana, mainly Tuesday evening and into the overnight hours. ...Synopsis... A mid-/upper-level short-wave trough will continue digging southeastward across the Four Corners states during the day Tuesday, before arcing more eastward into the across the southern Plains overnight. As this system advances, weak/gradual surface wave development is expected along the primary baroclinic zone across Texas during the day. With time, as the wave shifts eastward to the Texas Coastal Plain by evening, a southward surge of Arctic air will occur in its wake. Overnight, this wave should continue eastward roughly along the western Gulf Coast, reaching the vicinity of the mouth of the Mississippi by 12Z Wednesday. By this time, the trailing cold front will likely have reached the western Gulf, with cold air penetrating south of the Rio Grande into northern Mexico. ...Southeastern Texas eastward across southern Louisiana... A broad zone of low-level theta-e advection is expected across all but western portions of the southern Plains at the start of the period, shifting gradually eastward across the Sabine and Lower Mississippi Valleys, and reaching central Gulf Coast and eventually the Southeast states overnight. As the relatively warm/moist air spreads northward atop a still-cool/stable boundary layer, elevated convection is forecast to gradually increase/expand across the eastern half of the southern Plains and into Arkansas/Louisiana through the day. By late afternoon/early evening, some convection will likely have deepened sufficiently to produce some lightning, with thunderstorm coverage then increasing and spreading eastward through the overnight hours in tandem with the advance of the aforementioned surface wave. With convection largely remaining elevated, severe potential will likely be relegated to marginal hail with a few of the strongest storms, largely evolving after sunset. Potential for near-surface-based storms will remain confined to southern portions of the MRGL risk area, where gusty winds may occur with one or two of the strongest storms. Any risk for a tornado will remain even more limited -- confined to coastal areas of southern Louisiana, and most likely after midnight. ..Goss.. 02/17/2025 Read more

SPC Day 1 Fire Weather Outlook
Day 1 Fire Weather Outlook NWS Storm Prediction Center Norman OK 1028 AM CST Mon Feb 17 2025 Valid 171700Z - 181200Z No changes. See previous discussion below. ..Bentley.. 02/17/2025 .PREV DISCUSSION... /ISSUED 1158 PM CST Sun Feb 16 2025/ ...Synopsis... A disturbance will bring enhanced westerly flow today across California into the desert southwest and across the southern Rockies. This will lead to an increase in surface winds across southern Arizona into New Mexico, as well as into the southern high Plains as lee troughing strengthens and surface low development occurs. This will promote windy and dry conditions from southern Arizona into New Mexico. Across western Texas into southern New Mexico, ERCs will generally be around the 50th-75th percentile. Across southern Arizona, very little rainfall/snowfall has been observed, with ERCs also near the 75th percentile. Within these regions, overlap of relative humidity to around 15-20 percent with sustained winds around 15-20 mph (gusting locally higher) will be possible. Hi-res guidance from the HREF suggests longest duration Critical conditions would be tied to favored downslope regions near terrain features. As such, an Elevated was maintained with this outlook but locally Critical fire weather will be possible. Elevated to critical meteorological conditions will likely extend into northeastern New Mexico. However, fuels in this region are below the 50th percentile which will preclude the need to include additional Elevated or Critical areas. ...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 1012 AM CST Mon Feb 17 2025 Valid 171630Z - 181200Z ...NO THUNDERSTORM AREAS FORECAST... ...SUMMARY... Thunderstorms are not forecast through tonight across the contiguous United States. ...Synopsis... A cold, continental-polar airmass is in place across the much of the Lower 48 today due to a 1045-mb surface high centered over the ND/Canada border region. Dry/cool offshore flow this morning has led to tranquil conditions across much of the Eastern Seaboard and Gulf coastlines. As a cold front pushes south across the central into the southern Great Plains, low-level flow will veer across the northwest Gulf Coast with onshore flow beginning mainly tonight. Thunderstorm potential in this region will be negated by the onset and limited duration of moisture return into the TX Gulf Coast. Cool/dry conditions will be pervasive across much of the CONUS. ..Smith/Lyons.. 02/17/2025 Read more