Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 03/13/25


AREA FORECAST DISCUSSION
National Weather Service Eureka CA
323 PM PDT Wed Mar 12 2025 .SYNOPSIS...Risk for very slippery road conditions will increase tonight through Thursday morning as the potential for small hail and low elevation heavy snow showers increase. A brief break is anticipated Thursday evening before the next round of low elevation snow arrives by Friday morning. Snow levels should rise over the weekend as a moderate atmospheric river storm brings an increase risk for heavy rain and strong winds. && .DISCUSSION...Frontal boundary moving across the area today has been producing widespread moderate to locally rainfall. As of 2 PM, 24 hour totals generally ranged from 0.50 to 1.0in with higher amounts in the King Range (2.00-2.50) and 1.0 to 1.5 inches in Del Norte. Prime concern going into tonight and Thu is lowering snow levels and potential for accumulations above 1500-2500 feet. Precip rates and coverage will fall off tonight in the showery air mass regime after frontal passage, however impacts will be much greater as snow levels plummet to 1500-2000 feet by early Thu. Thus we hoisted a winter weather advisory for most all interior zones tonight/early Thu AM where just 1-2 inches could create slippery driving condition and impact travel on major highways. Snow levels should rise up during the day on Thursday and potential for localized intense precip rates should diminish in the afternoon. HRRR is by far the most aggressive with heavier precip rates compared to other CAMS in the HREF. A winter storm warning remains in effect for Trinity County with hefty accumulations of a foot or more likely above 3500 feet. Snow accumulations for lower elevations are less certain for Trinity tonight behind the frontal boundary in the showery air mass. Westerly upslope flow into the coastal ranges of Del Norte and Humboldt should support snow amounts sufficient for a winter weather advisory with totals of 3-5 inches above 2000-2500 feet by 11 AM Thu. This will have significant impact on travel over Berry Summit on 299 as well as route 36 around Dinsmore. Confidence is less for Del Norte on route 199 where an inch or two could accumulate by 11 AM Thu. Another hazard tonight into Thu is small hail with convective storms. Impacts may be much greater considering how rapidly hail accumulates in what may seem like safe driving conditions. We may end up needing a winter weather advisory for coastal areas if the hail accumulates, causing multiple pile ups. We will continue to message this insidious hazard via social media outlets and a weather story graphic on our webpage. Convective allowing models continue to show simulate composite reflectivities over 40dBz and we will need to monitor the activity for the possibility of strong storms and perhaps waterspouts in the lee of Cape Mendocino/around Shelter Cove. After a brief break Thu evening, another storm with low snow levels (1500-2500 feet) is forecast to arrive quickly late Thu night into Friday morning. Snow levels will start out lower with this next round of precip and impacts on major travel corridors and populations will likely be greater even though overall snow amounts will be lower compared to today`s storm. We may see a break in the active and wet weather on Saturday as a ridge pumps up over the area. An atmospheric river storm (AR1/AR2) will likely bring another bout of moderate to heavy rain and possibly hefty high mountain snow as well as strong winds toward the latter portion of the weekend and early next week. Snow levels should rise up over the weekend, however travel impacts above 4000-4500 feet are possible. There is still a great deal of variability and spread with the timing and magnitude of winds with this next storm and fine details are difficult to resolve multiple days out. Stay tuned for updates. Another break in the wet and active weather is forecast for Tuesday as a transient ridge builds. The active flow pattern with periods of precip will probably continue mid to late week next before more stout ridging aloft returns. DB && .AVIATION...A cold front, developed into a frontal wave and ushered in much rain today. Shortly after noonday, the frontal wave began to move onto the North Coast. Therefore, airport impacts became more substantial due to Cig/Vis lowering and rain intensities becoming greater. A threatening flight hazard today was LLWS, associated with a low level jet, ahead of the front. The LLWS hazard diminished as the wave moved onshore. Surface winds were less along the coast as the pressure gradient was more relaxed around a low center off the Del Norte Coast...and associated with the frontal wave. However, the gradient was greater over the Mendocino Interior resulting in continue gusty winds at UKI. As rain persisted today, embedded showers were frequent along the North Coast. These showers, some heavy, will bring a few periods of IFR conditions to the coastal terminals. Convection possibilities will be greater in the evening as instability increases. VCTS is appropriate to be added to the coastal TAFs tonight. /TA && .MARINE...A strong frontal system passed through this waters this morning and gale to strong gale criteria were met in all waters. Winds have eased behind an area of low pressure which followed the front, and the heightened steep, wind driven seas will continue to slowly subside. The southerly winds became quite strong in the southern zones today as the low moved ashore, and steep, hazardous seas are expected in those zones into the late afternoon. Seas are not likely to drop below 10 ft as a 14 second WNW swell builds to 10- 12 ft through Thursday. Winds turn northwest up to 20 kts tonight behind the front. Winds will only briefly ease Thursday before southerly winds increase again Thursday night into Friday with the next strong frontal system. Gale strength winds are forecast, and Gale Watches are up for all zones. As the steep wind driven southerly waves subside, a steep westerly swell will then build in Friday evening at around 12-14 ft at 12 seconds and may contribute to a chaotic sea state. Southerly winds are then forecast to once again increase Saturday through Sunday, and gale conditions with potential steep and hazardous seas look likely again with that frontal system. JJW && .EKA WATCHES/WARNINGS/ADVISORIES... CA... Winter Weather Advisory from 5 PM this afternoon to 5 PM PDT Thursday for CAZ102-105. Winter Storm Watch from Thursday evening through Friday evening for CAZ102-105-111-114. Wind Advisory until 2 PM PDT this afternoon for CAZ104>106. Winter Weather Advisory from 11 PM this evening to 11 AM PDT Thursday for CAZ104-106-110-111-113>115. Winter Storm Warning until 8 PM PDT this evening for CAZ107- 108. Winter Storm Watch from late Thursday night through Friday evening for CAZ107-108. Wind Advisory until 5 PM PDT this afternoon for CAZ109-110- 112-113-115. Winter Storm Watch from late Thursday night through Friday afternoon for CAZ110-115. NORTHWEST CALIFORNIA COASTAL WATERS... Small Craft Advisory until 6 PM PDT this evening for PZZ450- 470. Gale Warning until 2 PM PDT this afternoon for PZZ455-475. && $$ Visit us at https://www.weather.gov/eureka Follow us on Facebook and Twitter at: https://www.facebook.com/NWSEureka https://www.twitter.com/NWSEureka For forecast zone information see the forecast zone map online: https://www.weather.gov/images/eka/zonemap.png
Area Forecast Discussion
National Weather Service Huntsville AL
900 PM CDT Wed Mar 12 2025 ...New NEAR TERM, SHORT TERM, LONG TERM... .NEAR TERM... (Tonight) Issued at 900 PM CDT Wed Mar 12 2025 Deep layer shortwave in OK/TX will rapidly trek east tonight spreading high clouds into the region. With a tightening pressure gradient at the surface, south to southwest flow will persist at times at 5-10kt, keeping temperatures on the mild side in the lower to middle 50s for most areas. The exception will be the eastern valleys where the sky remains clear and flow is light or calm the longest. So in these areas, lows will be in the upper 40s. && .SHORT TERM... (Thursday through Saturday night) Issued at 900 PM CDT Wed Mar 12 2025 The wave will swing a negative tilted spoke of vorticity and moisture in mid levels through Thursday morning into the midday hours. This may generate some shower activity, and possibly a storm or two, but the HRRR suggests the main area of thunderstorms now in east TX (and handled by the HRRR rather well currently) will push east through southern AR, central MS, into mainly southern AL. While the ARW and others suggest a more solid band further north into north AL. Another pocket of convection will generate near the center of the low through northern MS eventually reaching northwest AL during the afternoon hours. These storms may produce hail as they generally glide east-southeast, mainly into central AL during the evening hours. So overall, the greatest risk of strong thunderstorms may be to our south on Thursday, but our southwest counties may have a low potential for a strong storm or two with hail potential. Given the clouds and precipitation, high temperatures Thursday will be held into the lower 70s in valley locations and upper 60s atop the higher elevations. Friday still looks to be a warm and breezy day as the long predicted surface cyclone emerges in KS and southern NE. High temperatures will easily climb into the upper 70s to around 80. Southerly winds will gust at 20-25 mph at times. Dew points will climb into the middle to upper 50s, although afternoon mixing may dip them back into the lower 50s. ...Friday Night... Not much change in thinking for Friday night. The EML will overspread the lower MS valley entering the TN valley Friday night. This will provide steep mid level lapse rates atop a capping inversion. With the main upper trough axis and -divQ field lifting well north east into the upper Midwest and Great Lakes, QG forcing will be limited further south. However, many models indicate isolated to scattered cellular development after 06Z, and especially after 09Z across MS spreading northeast into AL and middle TN. With the deeply sheared environment and favorable hodograph, and MUCAPE of 1000-1500 J/kg, supercells are indeed the favored storm type. ...Saturday and Saturday Night... On Saturday, a negatively stacked low pressure system will push northeast towards the Great Lakes Region with a deep upper level trough located across the southern Plains. A cold front positioned to the south of the low will be draped down from the Midwest into the MS River Valley. By Saturday morning, a sfc meso- low is forecast to develop in central MS and lift to the northeast. Showers and storms will develop ahead of this sfc cyclone in an environment primed for severe storms. Ensemble model guidance shows a mean 750-1000 J/kg of CAPE with some members indicating over 1500 J/kg Saturday morning. Despite some potential morning convection, instability is forecast to increase through the morning hours and into the afternoon. By around lunchtime, low level wind fields begin to ramp up increasing to 70-80 kts at 850 mb with 0-1 km shear between 35-45 kts. This environment would be favorable for supercells. Given the good overlap of instability and shear, tornadoes, hail, and damaging wind gusts are all possible. Flash flooding may also become a concern given the potential for multiple rounds of thunderstorms. The first round being the supercells and the second the line of storms along the front. PWs increase to around 1.5 inches which would indicate heavy rain potential. Current forecast has between 2-3 inches areawide with locally higher amounts in the most intense thunderstorms. Showers and storms will clear the area around midnight. && .LONG TERM... (Sunday through Wednesday) Issued at 900 PM CDT Wed Mar 12 2025 With the powerful frontal system located along the East Coast on Sunday a much needed tranquil period of weather is forecast for the Tennessee Valley through the long term forecast period. Cooler and drier conditions return on Sunday with highs in the low 60s. As we start next week, the upper level trough axis pushes further off the East Coast which will help usher in a longwave upper level ridge into the central CONUS. Northwest flow continues on Monday resulting in highs once again in the 60s, but sfc winds back to the southwest by Tuesday and Wednesday. This results in temperatures increasing into the low 70s as we head into the middle of the week. && .AVIATION... (00Z TAFS) Issued at 445 PM CDT Wed Mar 12 2025 VFR flight weather conditions are expected through 09-10Z before ceilings of 020-025agl (MVFR) arrive. Scattered -SHRA and possibly a few TSRA will occur from 14-20Z from west to east across north AL and southern middle TN as a fast moving upper level low pressure system pushes east through the region. A return to VFR conditions is expected after 18Z-19Z. && .HUN WATCHES/WARNINGS/ADVISORIES... AL...None. TN...None. && $$ NEAR TERM...17 SHORT TERM....17/GH LONG TERM....GH AVIATION...17
Area Forecast Discussion...UPDATED
National Weather Service Los Angeles/Oxnard CA
842 PM PDT Wed Mar 12 2025 .SYNOPSIS...12/715 PM. A strong storm will move across the area tonight with periods of heavy rain, mountain snow, and gusty winds. Thursday will continue to be unsettled with periodic showers, a chance of thunderstorms, periods of heavy rain and lower elevation snow, but with some sunny breaks as well. Light showers expected Friday then dry and warmer over the weekend. && .SHORT TERM (WED-SAT)...12/835 PM. ***UPDATE*** The warm front did not really live up to advanced billing with most of the area seeing mostly dry conditions. The foothills and coastal slopes saw a little more rain. Over all about a tenth of an inch fell across the flatter portions of the csts/vlys and a third to locally 2 thirds of an inch across the coastal slopes of VTA and SBA counties. Max temps were about 12 degrees under normals today with cst/vly temps coming in a few degrees either side of 60. The main front is over the Central Coast and is living up to expectations with heavy rainfall, waterspouts, downbursts and strong straight line winds. No lightning has been observed yet, but TSTMs are a possibility with this front as well. Frontal timing by way of the latest HRRR shows it over SBA city between 9 and 10pm, VTA county between 1030pm and 200am and LA county between 200am and 600am. Satellite shows plenty of convection under the upper low to the west of SLO county and this bodes well for scattered convection tomorrow. Forecast was massaged with rain chances and clouds. ***From Previous Discussion*** This storm will pack quite a wallop despite it`s short duration as a strong southerly low level jet will interact with a narrow but potent frontal band with PW`s projected to be close to 1.2". So the necessary ingredients will be in place to generate a 3 to 6 hour period of very heavy rain tonight, especially near and on the south facing mountain slopes from Santa Barbara to LA County. Hi res ensembles have been consistent showing a 60-80% chance of rain rates reaching a half inch per hour somewhere in those upslope areas and a 10-20% chance of hourly rates close to an inch per hour. Sub-hourly rain rates may be just as or perhaps even more important to monitor as it`s likely those will be exceeded as well. Strong winds at times are expected, especially interior SLO County. Thunderstorms are possible as well, though the best chances for those will likely be following the frontal passage Thursday as the colder and more unstable air moves in. PW`s drop about 50% during this phase of the storm but with the colder and more unstable air present periods of very heavy rain, along with small hail, gusty winds, and possibly even a waterspout or small tornado are all possible through the day so the threat of flooding and debris flows will continue through at least Thursday afternoon. Snow levels will stay at or above 6000 feet for most of the night but then will fall rapidly Thursday down to around 3000 feet. There may be some light accumulations on some of the lower mountain passes including the Grapevine on Interstate 5, highway 14 and 33, as well as possibly Highway 154 over San Marcos Pass, and some of the Santa Lucias. Up to 1 to 2 feet of snow expected above 6000 feet with lighter amounts below that. Showers are expected to decrease late in the day and evening Thursday. However, another area of showers is expected to move through Friday into early Saturday. Additional amounts are expected to from around a half inch north of Pt Conception to around a quarter inch or less south. .LONG TERM (SUN-WED)...12/211 PM. A weak high pressure ridge will bring a return to dry and warmer weather late Saturday into Sunday. Another system will arrive late Sunday night into Monday with another round of mostly light showers with little to no impacts. Still some uncertainty with this one as some of the ensemble solutions keep most of the precipitation north of Pt Conception. The rest of the week looks dry and slightly warmer. Some gusty northerly winds possible Tuesday and Wednesday, with small chances of a weak Santa Ana. && .AVIATION...12/2309Z. At 2255Z at KLAX, there was no marine layer or inversion. Overall, low to moderate confidence in 00Z TAF package. Potent cold front will sweep across all sites from 00Z-12Z, bringing moderate to heavy rainfall and CIG/VSBY restrictions. However, low confidence in exact flight categories with front (could range from MVFR to LIFR) and only moderate confidence in timing of rain/flight category changes (+/- 2 hours of current forecasts). After 12Z, precipitation will turn showery and flight categories will improve to MVFR/VFR levels, but confidence in timing of category changes will remain low. Also, gusty westerly winds can be expected Thursday morning through the afternoon behind the frontal passage. There is a 10-20% chance of thunderstorms for all sites through the TAF period. Any thunderstorms that develop will be capable of brief heavy rain, small hail, gusty and erratic winds and frequent lightning. KLAX...Low to moderate confidence in 00Z TAF. High confidence in cold front passage overnight, but low confidence in flight categories associated with front and moderate confidence in timing of frontal passage/flight category changes (could be +/- 2 hours of current forecasts). Moderate confidence in southeasterly winds 10-15 knots through 11Z, then switch to gusty westerly winds after 11Z behind front as flight categories improve. There is a 10-20% chance of thunderstorms through the period. KBUR...Low to moderate confidence in 00Z TAF. High confidence in cold front passage overnight, but low confidence in flight categories associated with front and moderate confidence in timing of frontal passage/flight category changes (could be +/- 2 hours of current forecasts). There is a 10-20% chance of thunderstorms through the period. && .MARINE...12/800pm. Hazardous sea conditions will continue through Friday. Stay in safe harbor. Wait for the weekend with improved conditions. Very confused seas will continue through Thursday, with both long period northwest to west swell and short period southwest swell along with southerly wind waves. A moderate to strong cold front currently moving into the western Santa Barbara channel will move through the area from through the rest of the waters overnight. overnight hours. All areas will see at least a few hours of high end Small Craft Advisory (SCA) level south winds today, with low end Gale Force winds expected north of Point Conception. For the waters south of Point Conception, there is a 40-50% chance of brief Gale Force winds as the front passes through the region, but winds will be localized and short lived, thus a Gale Warning will not be issued at the moment. Rain will be heavy at times, with a chance of thunderstorms (through Thursday afternoon) and associated hazards like locally strong winds, lightning, and waterspouts. Post-frontal west to northwest winds will quickly form later tonight into Thursday, with a 40-60% chance of reaching Gale Force south of Point Conception. Best chances in zones PZZ650/655 especially for the nearshore waters from Point Mugu to Santa Monica, and the San Pedro Channel. Another storm will move through the area on Friday, with another round of gusty south winds and post frontal west to northwest winds. Winds should be weaker than today/Thursday, but SCA-levels are likely over most waters. && .LOX WATCHES/WARNINGS/ADVISORIES... CA...Wind Advisory remains in effect until 10 PM PDT this evening for zones 38-340>343-346>349-351. (See LAXNPWLOX). Flood Watch remains in effect through Thursday afternoon for zones 87-88-349>352-354>358-362-366>375-378>380-548. (See LAXFFALOX). High Surf Advisory in effect until 9 PM PDT Friday for zones 340-346. (See LAXCFWLOX). High Wind Warning remains in effect until 2 AM PDT Thursday for zones 344-345. (See LAXNPWLOX). Winter Storm Warning remains in effect until 5 AM PDT Saturday for zones 353-376>382. (See LAXWSWLOX). High Surf Advisory in effect from 9 AM Thursday to 3 PM PDT Friday for zones 354-362-366. (See LAXCFWLOX). Wind Advisory remains in effect until 6 AM PDT Thursday for zones 369-370-375. (See LAXNPWLOX). Wind Advisory now in effect until midnight PDT tonight for zone 383. (See LAXNPWLOX). Wind Advisory now in effect from midnight tonight to 6 AM PDT Thursday for zone 383. (See LAXNPWLOX). PZ...Small Craft Advisory in effect until 3 AM PDT Friday for zones 645-670-673. (See LAXMWWLOX). Small Craft Advisory in effect until noon PDT Thursday for zones 650-655. (See LAXMWWLOX). Gale Watch in effect from Thursday morning through Thursday evening for zones 650-655-676. (See LAXMWWLOX). Small Craft Advisory in effect until 9 AM PDT Thursday for zone 676. (See LAXMWWLOX). && $$ PUBLIC...MW/Rorke AVIATION...RAT MARINE...Phillips/Lewis/Black SYNOPSIS...MW/Smith weather.gov/losangeles Experimental Graphical Hazardous Weather Outlook at: https://www.weather.gov/erh/ghwo?wfo=lox
forecast discussion will be broken up by day.

Late Tonight into Thursday - a stout shortwave trough will dig across the ArkLaTex region. The most recent CAMs depict showers and thunderstorms developing over east central Texas this evening, eventually congealing into a bowing line segment. The best severe parameters exist over central Mississippi overnight, with the Mid-South centered underneath the upper level low. Locally, storms will be hindered by decreasing shear and lapse rates. Therefore, expect any storms tonight to become outflow dominate, posing a low (5%) severe storm risk. The greater chances for severe storm development occur Thursday morning as daytime heating quickly allows for SBCAPE values to increase to about 400 J/kg by mid-morning. The 18Z HRRR depicts a secondary line of storms developing over north MS after sunrise, trekking southeast into Alabama. The greatest threat with these storms will be damaging winds and hail. Friday - A rather concerning synoptic pattern emerges on Friday as a strong, negatively tilted trough ejects from the Rockies. At the surface, dewpoints begin increasing to the upper 50s and low 60s by midday. The exact northward extend of moisture availability remains uncertain due to a southerly shift in 60s dewpoints on the GFS and ECMWF. Regardless, guidance continues to depict a line of storms developing over the Midwest, pushing eastward into the evening. The greatest uncertainty with this line lies in the southerly portion, as storms may struggle to overcome a capping inversion. Both the GFS and ECMWF develop a cap by Friday morning. However, each solution varies widely in airmass modification throughout the day. In fact, the ECMWF remains the more bullish of the two as it favors a southern extent QLCS that moves through an environment comprised of 700-1000 J/kg of SBCAPE and bulk shear on the order of 65 kts. On the other hand, the GFS struggles to initialize storms this far south and favors a more persistent cap. Despite model differences, it is important to note that any storms that do move into the area will likely experience significant upscale growth, posing a damaging wind and tornado threat into the overnight hours. Saturday - Quickly on the heels of Friday`s trough, a secondary trough emerges over the Gulf Coast Region on Saturday. Moisture availability will surge over north MS on Saturday, with many solutions depicting mid 60s dewpoints in place by midday. In addition, severe parameters become even more conducive for severe storm development as lapse rates exceed 7.0 C/km, SBCAPE rises above 1500 J/kg and bulk shear nears 60 kts. One thing to watch on Saturday is the potential for a contaminated warm sector as large areas of convection kick off in the morning. In fact, both the GFS and ECMWF depict the best severe parameters waning by midday due to multiple rounds of convection in the early morning. However, areas in northeast MS appear to quickly recover after the morning convection. Looping hodographs suggest potential supercell development in the afternoon and evening. As such, the Storm Prediction Center continues to keep extreme northeast MS in a 30% (equivalent to an Enhanced Risk) area on their Day 4 outlook. All severe weather hazards are at play for northeast MS on Saturday. As we move into this active pattern, we suggest you ensure you have multiple ways to receive warnings. Check your weather radio batteries and monitor the forecast for changes. ANS && .AVIATION... (00Z TAFS) Issued at 625 PM CDT Wed Mar 12 2025 VFR conditions will remain across the airspace through much of the TAF period. The biggest question this issuance remains timing and intensity of convection tomorrow morning with the movement of an upper low. Previous PROB30s were changed to TEMPOs at MEM and TUP as subsequent CAM runs have aligned decently on timing and placement of the upper low. As thunderstorms move across terminals, a brief drop to MVFR will likely occur. Wind gusts, up to 20 kts, will drop in and out this evening, ahead of convection. Otherwise, south winds will be predominately sub 10 kts. AEH && .MEG WATCHES/WARNINGS/ADVISORIES... AR...None. MO...None. MS...None. TN...None. && $$ PUBLIC FORECAST...SJM AVIATION...AEH
Area Forecast Discussion
National Weather Service Raleigh NC
856 PM EDT Wed Mar 12 2025 .SYNOPSIS... High pressure will build from the southern states to near Bermuda ahead of a moisture-starved mid and upper-level disturbance that will move across the Carolinas Thursday and Thursday night. && .NEAR TERM /THROUGH TONIGHT/... As of 130 PM Wednesday... Sunny and dry through tonight. Temperatures this afternoon are well into the mid to upper 70s, a few warmer spots could see 80 degrees. High pressure remains over the area as a weak upper level short wave shifts across the TN/OH valley this afternoon and evening. A few high clouds will move in and out of the area late this afternoon and early evening. RH values still expected to drop into the upper teens to low 20s this afternoon across much of the western Piedmont and portions of the Sandhills. The IFD statement will continue through at least 8pm this evening. Lows tonight will be in the mid to upper 40s. && .SHORT TERM /THURSDAY AND THURSDAY NIGHT/... As of 135 PM Wednesday... A mid/upper level trough will move across the region Thursday with increased moisture in the atmosphere. However, Thursday is expected to be dry. We will see some mid to high clouds move across the region mid morning through early evening which will result in slightly cooler temperatures than Wednesday. Highs will range from low 70s near the VA/NC border to mid upper 70s elsewhere. Lows will be similar to Wednesday nights, ranging from the mid/upper 40s. && .LONG TERM /FRIDAY THROUGH WEDNESDAY... As of 315 PM Wednesday... * A strong cold front will bring strong winds and a threat for severe storms/squall line Sunday... * Unseasonably warm through much of the period... Friday: In the wake of the exiting low-amplitude/sheared shortwave trough, shortwave ridging will briefly build over the SE US Friday. The stalled sfc front across the area will quickly retreat north as a warm front during the day. Due to the dry stable air in place, dry conditions should persist with a continuation of warm/mild temperatures. Highs ranging from lower/mid 70s north to upper 70s/near 80 south. Saturday: The eastward advancement of the strong upper trough into the Central US and MS Valley will kick the mid/upper level offshore early in the day. Strengthening southerly flow and associated moisture transport between offshore Bermuda high pressure and the upstream trough/cold front will result in some weak buoyancy and chance of some diurnally driven isolated to widely scattered shower activity. Otherwise, becoming breezy and a few degrees warmer than Friday. Highs in the mid 70s to lower 80s. Saturday night and Sunday: A strong upper trough will advance east into the region late Sunday and into the day on Monday. Strong deep- layer southwesterly flow ahead of the trough, highlighted by a 100kt H5 jet and a 60-70 kt wind maximum at H8, will precede the passage of a cold front that will cross the area Sunday night. Even outside of any storms, these strong background flow will result in gusts of 30-40 mph at times late Saturday and Sunday. Weak destabilization is possible across the area as BL dewpoints increase into the lower/mid 60s. Convective onset/timing will likely play a critical role in how the lead convective line evolves as it moves east through the area with an earlier onset likely to temper or restrict severe chances to eastern portions of the forecast area. Given, strong, cyclonic curved hodographs, swaths of strong to severe gusts and supercell capable of producing tornadoes is possible. Additionally, the development of a secondary band of showers/storms is possible along the actual cold front as it moves east through the area Sunday evening/night. There remains timing discrepancies in the termination of PoPs across the area, with some of the slower solutions keeping precip across eastern NC into the day on Monday. Storm total rainfall of 1-2 inches could lead to some isolated/localized instances of minor flooding, mainly in urban/poor drainage environments. Monday through Wednesday: A period of of light ana-frontal rain could linger across eastern NC early Monday . Otherwise, drying out behind the exiting trough. Temperatures will cool down briefly to near normal Monday/Monday night only to quickly return to well-above normal readings(75-80 F) by mid week as the next trough/cold front approaches from the west. Rain chances could return as early as Wednesday night. && .AVIATION /00Z THURSDAY THROUGH MONDAY/... As of 830 PM Wednesday... High pressure and a related dry, continental air mass over the South Atlantic states will favor VFR weather conditions in cntl NC through Thu. However, there were multiple pilot reports of smoke and/or haze, and restrictions to visibility at flight levels between 3000-8000 ft AGL Wed afternoon, around a wildfire ("Falls Dam") centered about 20 miles southwest of HBI, or about 10 miles southeast of VUJ. A combination of smoke from that fire and others over the Southeast, including from a few prescribed/controlled burns over the NC Sandhills, may marginally restrict surface visibility at RDU tonight based on extrapolation of those plumes from late afternoon visible satellite imagery and also recent HRRR model forecasts of surface smoke. A weakening and moisture-starved mid and upper-level disturbance will result in an increase in mid/upr-level moisture and clouds on Thu, but associated ceilings should remain at or above 15 thousand ft. Outlook: An area of IFR stratus will develop behind a backdoor cold front from sern and srn VA swwd into nrn NC Fri morning; and these clouds and ceilings may reach RWI, INT, and GSO before lifting to VFR with daytime heating through midday Fri. Swly flow will then strengthen and transport moisture into the Carolinas by this weekend, with an associated chance of IFR-MVFR stratus Sat morning and light showers Sat afternoon. A better chance of MVFR ceilings will result Sat night-Sun morning, followed by the passage of a band of showers/storms along a passing cold front on Sun. Very strong and gusty swly surface winds will also result especially ahead of the cold front this weekend. && .FIRE WEATHER... As of 855 PM Wednesday... NCFS has requested and coordinated with NWS Forecast Offices another day of Increased Fire Danger for a large part of NC for Thursday. A continued very dry and warm, continental air mass will favor minimum relatively humidity values mostly between 20-30 percent Thu afternoon. RH will be slightly higher over the nrn Coastal Plain and far northeast Piedmont, where the proximity of a backdoor front will favor RH values between 30-40 percent. Surface winds will be mainly light swly and mitigate an otherwise greater threat of fire danger, with highest speed between 10-15 mph likely over the Sandhills and srn and cntl Coastal Plain. && .RAH WATCHES/WARNINGS/ADVISORIES... None. && $$ SYNOPSIS...MWS NEAR TERM...CA SHORT TERM...CA LONG TERM...CBL AVIATION...MWS FIRE WEATHER...MWS
Area Forecast Discussion
National Weather Service Shreveport LA
933 PM CDT Wed Mar 12 2025 ...New UPDATE... .UPDATE... Issued at 931 PM CDT Wed Mar 12 2025 In this update, Severe Thunderstorm Watch #29 has been trimmed back to Deep East Texas into Louisiana to account for the latest position of the convective cluster. Large hail and damaging winds remain as a hazard that these storms are capable of producing, although the latest environmental trends suggest that storm intensity has peaked. Plentiful lightning hazards will also remain with this cluster as strikes have occurred 10 to 20 miles ahead of the heaviest precipitation, so remain cautious/aware with any nighttime travel. /16/ && .SHORT TERM... (This evening through Thursday Night) Issued at 212 PM CDT Wed Mar 12 2025 Well mixed upper 70s and lower 80s at 3pm across our Four-State area. The SW winds have not dried the air much with mid to upper 50 dew points areawide. Skies are mostly sunny everywhere except deep east TX and Toledo Bend Country of LA with some stratocu streeting. Just the last hour or two we see some midlevel gathering of moisture from Tyler to Terrel on a lead push with more clouds concentrated around the short wave and TCUs over Abilene now. The HRRR has continued to trend farther south with development in the coming hours. The SPC alerted us to this with the midday day one update extending the Slight Risk down over more of our TX counties. And accordingly, we have a mention of severe with the current MCD extending into our TX counties and the expectation to move eastward this evening into S AR. The convective development will be quick as heating peaks with the same severe expectations of mostly large hail as the dominant threat with a quarter inch of rain for some. The upper level feature will see a surface reflection a low forming late this afternoon over our western most fringe of counties. Moisture will be most useful here with a notable drop in coverage over our I-30 from the past several runs with this system. Skies will become fair in the wake overnight with lows back in the 50s just about areawide by daybreak. We will be keeping the S/SW winds into the long term, so highs too will be back in the low to mid 80s for Thursday afternoon. Overnight under fair skies to partly cloudy skies, our lows will range again in the mid to upper 50s. The moon will be full this second short term night at 1:55 am with a totally eclipsed "Worm" blood moon, appearing reddish for those interested as the sun`s light picks up on dust in the earth`s atmosphere. This full moon is a big cue for the Spring fish spawn as we put on bow on whats left of Winter. /24/ && .LONG TERM... (Friday through next Tuesday) Issued at 212 PM CDT Wed Mar 12 2025 Friday afternoon will see more sunshine, but morning low clouds that may hone off a couple of degrees for the high temps which will be nice as will the start of the weekend. We will have more low clouds and eventually some rain clouds ahead of our next week cool front. The core upper low in the pattern will push off the front range and explode out over the plains, occluding Friday night. This will end up giving a minor push on Friday with limited moisture and then again Saturday`s daytime heating will develop more thunderstorms, mainly east of I-49 during the afternoon. The SPC has continued their day 3 with a Slight Risk for S AR and NE and central LA. So, good news for more of us as the event energy is split between two days of heating so to speak. The rest of the weekend looks very nice with NW winds and a 1022mb surface high drifting overhead into the next week. We will see winds back to SW for Monday with more warm temps to start the week and another chance to get wet overnight Tuesday into Wednesday. /24/ && .AVIATION... (00Z TAFS) Issued at 632 PM CDT Wed Mar 12 2025 For the 13/00Z TAFs, incoming thunderstorms from the west will begin to impact KTYR and KLFK within an hour or so. From there, storms will track quickly east, impacting KSHV and KMLU through the evening. Impacts to KTXK and KELD are less certain, but not being ruled out at this time. These impacts are reflected in TEMPO groups. Storms will bring large hail, torrential rainfall and damaging wind gusts. Locally higher gusts than depicted in groups may be possible. Storms will come to an end through the evening, with VFR conditions to follow, then lower VFR CIGs becoming MVFR towards daybreak, rebounding quickly into the late morning and afternoon tomorrow. Prevailing southerly winds will become westerly behind the frontal passage before becoming southerly again tomorrow, at sustained speeds of 5 to 10 kts with gusts of up to 20 kts possible. /26/ && .SPOTTER INFORMATION STATEMENT... Issued at 0931 PM CDT Wed Mar 12 2025 Spotter activation will remain necessary tonight across portions of Deep East Texas and Northwest Louisiana. && .PRELIMINARY POINT TEMPS/POPS... SHV 60 85 59 84 / 30 0 0 20 MLU 62 83 56 81 / 30 0 0 20 DEQ 51 82 53 79 / 30 0 0 20 TXK 57 83 59 83 / 30 0 0 20 ELD 57 82 55 81 / 30 0 0 20 TYR 56 84 59 81 / 20 0 0 10 GGG 56 85 59 84 / 30 0 0 10 LFK 58 86 58 84 / 40 0 0 10 && .SHV WATCHES/WARNINGS/ADVISORIES... AR...None. LA...None. OK...None. TX...None. && $$ SHORT TERM...16 LONG TERM....24 AVIATION...26
previous forecast discussion remains on track. A potent upper
level low will eject out of the Four Corners region and emerge
into the southern/central Plains on Friday. Attendant surface low will deepen to ~976 mb over eastern Colorado/western Kansas. Strong westerly winds at the mid levels (50-60 knots at 850 mb) will translate to 30-40 mph winds at the surface. There is also a high probability (greater than 70%) of winds gusts exceeding 50 mph across the Big Country and Concho Valley. These winds combined with very dry conditions will lead to critical fire weather conditions (see the fire weather discussion for further details). Upper level trough axis moves across the area on Saturday. Winds will not be nearly as strong as what is expected on Friday but will still be breezy out of the west-northwest in the afternoon. Afternoon highs will be in the 60s as a slightly cooler airmass settles into the region. Sunday will be quite pleasant with highs in the 70s and overnight lows in the 30s and 40s. Warmer and breezy conditions are expected for the beginning of next week as southerly flow resumes. Rain chances very remain low. && .AVIATION... (00Z TAFS) Issued at 623 PM CDT Wed Mar 12 2025 VFR conditions continue across West Central Texas terminals through Thursday afternoon. Some blowing dust will drop visibility some through mid evening before it settles out as the wind speed decreases. Wind speeds will decrease rapidly after sunset at most locations, with some gusty winds near 20 knots returning by Thursday afternoon. && .FIRE WEATHER... Issued at 242 PM CDT Wed Mar 12 2025 Critical to near critical fire weather conditions will continue through this evening to around 7 PM, so will leave the Red Flag Warning that has been issued in effect for the rest of this afternoon. Winds will quickly diminish to 10 MPH or less this evening, and remain less than 20 knots through Thursday. We may need an RFD for Thursday, but critical fire weather conditions are not expected. A Fire Weather Watch has been issued for Friday for the entire area for strong west winds and RH`s of 10% to 20%. A strong upper level low will move from northeastern New Mexico into eastern Kansas by Friday afternoon. West to southwest winds of 40 to 50 knots are expected at 850mb, 60 to 75 knots at 700mb, and 75 to 100+ knots at 500mb. At the surface, a deep surface low of less than 980mb will develop over western Kansas and move eastward throughout the day. This will create a tightened north to south surface pressure gradient to develop in our area, and increased westerly surface winds. With wind directions aligned well from the surface through the mid/upper levels, west winds of at least 30 to 40 MPH, with gusts up to around 60 MPH, and widespread blowing dust will develop by late Friday morning, especially north of Interstate 10. Although temperatures will be cooler, RH`s will still be able to fall well below 20%, as much drier air will move in with the west winds. A High Wind Warning may also be needed for parts of the area, mainly north of Interstate 10. Critical fire weather conditions are expected again on Saturday, mainly south of a Sterling City to Brownwood line. Northwest winds of 20 to 30 MPH, with gusts to 40+ MPH will develop in the wake of Friday`s Pacific cold front on Saturday. Although temperatures will likely only warm into the 60s, dewpoint values will be in the teens, allowing RH values to drop into the 15% to 20%. These winds, and low RH`s will combine with several days of drying which will also aid in the potential for hazardous fire weather conditions. Elevated to critical fire weather conditions are expected to persist through next Tuesday. && .PRELIMINARY POINT TEMPS/POPS... Abilene 51 84 59 72 / 0 0 0 0 San Angelo 50 85 57 72 / 0 0 0 0 Junction 48 88 58 80 / 0 0 0 0 Brownwood 48 86 56 75 / 0 0 0 0 Sweetwater 51 82 55 69 / 0 0 0 0 Ozona 50 83 57 73 / 0 0 0 0 Brady 53 86 62 76 / 0 0 0 0 && .SJT WATCHES/WARNINGS/ADVISORIES... Red Flag Warning until 9 PM CDT this evening for Brown-Callahan- Coke-Coleman-Concho-Crockett-Fisher-Haskell-Irion-Jones-Kimble- Mason-McCulloch-Menard-Nolan-Runnels-San Saba-Schleicher- Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green. Wind Advisory until 9 PM CDT this evening for Brown-Callahan- Coke-Coleman-Concho-Crockett-Fisher-Haskell-Irion-Jones-Kimble- Mason-McCulloch-Menard-Nolan-Runnels-San Saba-Schleicher- Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green. High Wind Watch from Friday morning through Friday evening for Brown-Callahan-Coke-Coleman-Concho-Fisher-Haskell-Irion-Jones- Nolan-Runnels-Shackelford-Sterling-Taylor-Throckmorton-Tom Green. Fire Weather Watch from Friday morning through Friday evening for Brown-Callahan-Coke-Coleman-Concho-Crockett-Fisher-Haskell- Irion-Jones-Kimble-Mason-McCulloch-Menard-Nolan-Runnels-San Saba- Schleicher-Shackelford-Sterling-Sutton-Taylor-Throckmorton-Tom Green. && $$ SHORT TERM...20 LONG TERM....42 AVIATION...07