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yoda

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  1. yoda
    SLGT risk pushed north to DC metro... MRGL to near Mason-Dixon line on 1300z SPC OTLK
  2. yoda
    Hmmm... later today surprise? NEAR TERM /THROUGH TONIGHT/... Showers and a few thunderstorms continue to slowly drift southeastward across the northern half of the forecast area early this morning. This remnant activity should continue to weaken over the coming hours, and eventually dissipate prior to daybreak. Clouds associated with this activity may linger for the first half of the morning, but clearing and ample sunshine is expected during the second half of the morning into the early afternoon. A diffuse cold front will continue to slowly drift southward across the forecast area today. Daytime heating will allow instability to build, with around 1000 J/kg of CAPE present by peak heating this afternoon. Additional thunderstorms are expected to develop within the zone of low-level convergence near the surface front later this afternoon. There`s some uncertainty as to where exactly this will occur. Any location in the forecast area has at least a slight chance for a thunderstorm, but the greatest chance should generally be south of I-66/US-50 and east of US-15. Further west, westerly flow and downsloping will act to further dry out an already dry boundary layer, which should limit storm coverage as a result. Further north, they`ll likely end up to the north of the best- low-level convergence, which should also limit the coverage of storms. Where storms do form, they`ll likely be strong to severe. Model soundings show an environment that is more typical of the High Plains than the Mid-Atlantic. Boundary layer moisture will be rather limited, with dewpoints only in the 50s, but lapse rates will be very steep (dry adiabatic in the lowest three kilometers, with mid- level lapse rates around 7.5-8 C/km). Flow will be relatively weak in the boundary layer, but pick up rapidly in the mid- levels, with continued shear through the upper levels. Hodographs are relatively straight, so storm splits may be possible, with both multicells and right/left moving supercells. Model soundings check a lot of boxes in recent research for hail producing storms. That may be the primary threat this afternoon, although the steep lapse rates and DCAPE values around 1000 J/kg should make damaging winds a threat as well. Tornadoes aren`t expected with a dry boundary layer and little to no low- level shear in place. The I-95 corridor south of DC to southern Maryland should stand the greatest chance of seeing a severe stoms. These storms will progress off to the south and east this evening, leading to dry conditions overnight.
  3. yoda
    New Day 1 has SLGT risk in W MD eastward till around HGR, also includes parts of the Panhandle of WV that borders Maryland
  4. yoda
    Could be interesting if any storm can get into our area tomorrow evening .SHORT TERM /SUNDAY THROUGH MONDAY NIGHT/... Flow aloft will become more zonal in nature tomorrow, with a broad belt of west-southwesterly flow extending from the Upper Midwest toward the East Coast. A shortwave disturbance will descend down in the west-northwesterly flow from the Great Lakes toward Upstate NY. A weak area of low pressure will accompany the shortwave, along with an attendant cold front which will drop southward out of NY into northern PA Sunday afternoon. Locally, it will be a warm day to the south of the boundary, with temperatures climbing into the upper 70s to near 80 beneath partly cloudy skies. Thunderstorms are expected to form near the aforementioned frontal boundary up in PA Sunday afternoon. Much of this activity is expected to remain to our north during the daylight hours. As we move into the evening and the first half of the overnight, these storms are expected to drift southward along with the frontal boundary, eventually reaching northern portions of the forecast area. With loss of daytime heating, the trend should be for these storms to gradually weaken as they move in from the north, but a few stronger storms can`t be ruled out. The environment will be an uncommon one for this part of the country, with steep lapse rates of 7-8.5 C/km in place as an elevated mixed layer moves in aloft. If storms do persist as they track into the area, some instances of large hail may be possible. SPC currently has portions of northern Maryland and the West Virginia Panhandle outlooked in a Marginal Risk for severe thunderstorms.
  5. yoda
    Yay wind URGENT - WEATHER MESSAGE National Weather Service Baltimore MD/Washington DC 1022 PM EDT Fri Apr 12 2024 DCZ001-MDZ005-006-011-013-014-503>508-VAZ053-054-506-526-131030- /O.EXB.KLWX.WI.Y.0015.240413T0400Z-240413T2200Z/ District of Columbia-Carroll-Northern Baltimore- Southern Baltimore-Prince Georges-Anne Arundel- Northwest Montgomery-Central and Southeast Montgomery- Northwest Howard-Central and Southeast Howard-Northwest Harford- Southeast Harford-Fairfax-Arlington/Falls Church/Alexandria- Eastern Loudoun-Northwest Prince William- Including the cities of Washington, Eldersburg, Westminster, Reisterstown, Cockeysville, Baltimore, Bowie, Suitland-Silver Hill, Clinton, College Park, Greenbelt, Laurel, Camp Springs, Glen Burnie, Annapolis, Severn, South Gate, Severna Park, Arnold, Odenton, Germantown, Damascus, Bethesda, Rockville, Gaithersburg, Silver Spring, Lisbon, Columbia, Ellicott City, Jarrettsville, Aberdeen, Reston, Herndon, Annandale, Centreville, Chantilly, McLean, Franconia, Arlington, Alexandria, Falls Church, Leesburg, Ashburn, Sterling, and Haymarket 1022 PM EDT Fri Apr 12 2024 ...WIND ADVISORY IN EFFECT UNTIL 6 PM EDT SATURDAY... * WHAT...West winds 15 to 25 mph with gusts around 45 mph overnight, increasing to 20 to 30 mph with gusts around 50 mph Saturday. * WHERE...Portions of central, north-central, and northern Maryland, The District of Columbia, and northern Virginia. * WHEN...Until 6 PM EDT Saturday. * IMPACTS...Gusty winds could blow around unsecured objects. Tree limbs could be blown down and a few power outages may result.
  6. yoda
    1630z OTLK disco ...Mid-Atlantic States and Carolinas... A less focused and less certain severe risk appears to exist across the region. Cloud cover remains prevalent at midday coincident with low-level upslope flow, although some clearing is noted early this afternoon across the southern Appalachians vicinity. Where modest destabilization does occur this afternoon, long hodographs would conditionally support storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, particularly near the mountains/Blue Ridge, with a lower probability/lesser anticipated storm coverage expected farther east over the coastal plain/Delmarva.
  7. yoda
    30 wind added in SW PA/W WV on 1630z OTLK
  8. yoda
    Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 1019 AM EDT Thu Apr 11 2024 .SYNOPSIS... Low pressure will track into the Great Lakes today, with an associated cold front moving through tonight. Upper troughing will linger overhead tomorrow, with a reinforcing cold front moving through tomorrow evening. High pressure will build to our south this weekend. A weak area of low pressure will track to our north late Sunday night into early Monday, before high pressure regains control early next week. && .NEAR TERM /THROUGH TONIGHT/... 1030 AM Update: Showers are starting to approach the area late this morning with some partial clearing happening across western portions of MD and the eastern WV panhandle. Temperatures are already climbing into the mid to upper 60s across the lower elevations. It is worth noting a dry slot building in behind the initial cold front passage affecting areas further south of our CWA. Discrete cells and clouds should begin building back in through the early afternoon with increasing rain chances.
  9. yoda
    Both 12z NAM and NAM NEST have some decent curved and looping hodographs around 06z in the region with 300 m2/s2 with 500 to 1000 SBCAPE
  10. yoda
    1300z SPC OTLK update Mid-Atlantic states into Carolinas... A less focused and more conditional severe risk seems evident for the Carolinas later this afternoon and northward into the Mid-Atlantic states this evening as the upper trough encroaches on the general region. A broad warm-air advection regime north of the FL/GA early-day MCS will slowly destabilize today, aided in part by lower 60 deg F dewpoints north, mid to upper 60s south. Long hodographs will favor storm organization with any robust updrafts. Isolated to widely scattered strong to severe storms capable of a threat for damaging gusts and a couple of tornadoes are possible, mainly over parts of western VA, with lower coverage expected farther east over the coastal plain/Delmarva.
  11. yoda
    Morning AFD from LWX on the threat The upper trough will take on a negative tilt as it moves overhead tonight. At the surface, low pressure will deepen as it tracks into the Ohio Valley. Thunderstorms are expected to form within the zone of strong forcing for ascent ahead of the negatively tilted trough across OH/WV/SW VA late this afternoon into early this evening. These storms should initially reach far southwestern portions of the forecast area during the late evening, before progressing northeastward across the remainder of the forecast area between 10 PM and 4 AM. Instability will increase through the evening as a low level mass response occurs ahead of the approaching trough. CAPE values are expected to increase to around 300-600 J/kg across much of the area. When coupled with an impressive low- level jet and ample deep layer shear present, some of the storms this evening into the overnight may be on the strong to severe side. Damaging winds should be the primary threat, but a brief tornado can`t be ruled out given the strong low-level jet, 0-1 km SRH values increasing to around 200-300 m2/s2, and STP values climbing above 1. Weak stabilization evident on forecast soundings right near the surface may potentially serve as a limiting factor for both the damaging wind and tornado potential. SPC currently has locations to the west of the Blue Ridge outlooked in a Slight Risk for severe thunderstorms, while locations to the east of the Blue Ridge are in a Marginal Risk.
  12. yoda
    Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1247 AM CDT Thu Apr 11 2024 Valid 111200Z - 121200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS ACROSS PARTS OF THE UPPER OHIO RIVER VALLEY... ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS ACROSS PORTIONS OF THE OHIO RIVER VALLEY AND NORTHERN FLORIDA TO SOUTHERN GEORGIA... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are possible across the upper Ohio River Valley and parts of the Appalachians this afternoon. Scattered damaging winds and a couple tornadoes will also be possible across southeast Georgia into northern Florida, mainly this morning through early afternoon. ...Synopsis... 04 UTC surface observations depict a diffuse surface low over the lower MS River Valley. This low is forecast to deepen over the next 24 hours as it lifts northward into the OH Valley/Great Lakes region in tandem with the phasing of an amplified upper-level trough over the MS Valley with an approaching upstream perturbation. A surface cold front currently draped across southeast LA will surge to the east/northeast as the low deepens, and should act to focus thunderstorm development through the late morning and afternoon hours across both the upper OH Valley and Southeast. ...Upper OH River Valley... Recent 925/850 mb analyses and surface observations show a consolidating warm frontal zone draped from the surface low over the lower MS Valley into the upper OH River Valley. The surface low will deepen along this corridor amid a combination of strong height falls and ascent within the left-exit region of a mid-level jet. A plume of low to mid-60s dewpoints will advect northward with the deepening low, establishing a focused warm sector ahead of the approaching cold front by early afternoon across parts of KY, OH, and WV. The current expectation is for sufficient destabilization within the warm sector to support surface-based convection by the 18-21 UTC time frame. A combination of strong synoptic-scale ascent and 40-50 knot deep-layer shear vectors off the cold front should promote a mix of discrete cells and semi-discrete clusters - including the potential for a few supercells. Increasing southeasterly winds through the lowest 1-2 km should yield effective SRH values between 150-300 m2/s2, which will support a tornado threat with the more robust/organized cells as well as a wind threat with more organized clusters. This threat appears greatest across southeast OH into western WV where latest guidance continues to show a focused convective signal. Further to the east into parts of northwest VA, a somewhat weaker convective signal is noted in most CAM guidance, but 50-knot flow in the lowest 2 km will likely pose a substantial wind threat with any storms that can mature. Risk probabilities have been expanded into this region to account for this potential. That said, this scenario appears to be conditional on achieving sufficient low-level warming within the warm sector. While an extensive dry slot is noted in water-vapor imagery across the Mid-South into central IN, the low/mid-level warm advection regime is maintaining mid-level stratus across the region with most ASOS stations reporting overcast skies and ceilings near 6 kft. It is unclear how much clearing will occur through early afternoon given persistent ascent, and a 10 F spread in afternoon high temperatures is noted across OH/WV in recent ensemble guidance. Based on forecast soundings, surface temperatures in the upper 60s may be required to realize 500+ J/kg SBCAPE with minimal inhibition. The median of the temperature distribution appears to reside in the upper 60s, but SBCAPE may still only reach 500-1000 J/kg per ensemble distributions.
  13. yoda
    SLGT risk moved into most of N VA and C MD on new Day 1 for 15 wind and 5 tornado
  14. yoda
  15. yoda
    Still MRGL on 1730z SPC OTLK... but a small ENH risk was added in E Ohio into West Virginia with 10% tor probs added
  16. yoda
    Might get a slight risk upgrade at 1730z
  17. yoda
    Updated morning AFD from LWX now mentions tornado threat SHORT TERM /THURSDAY THROUGH FRIDAY NIGHT/... Rain chances increase further Thursday morning as a frontal system inches closer to the region, but the bulk of precipitation likely arrives Thursday afternoon. Strong southerly winds are expected to develop ahead of the approaching cold front, which could reach 25 to 35 mph or so. The upper trough that is currently digging into the MS River Valley will lift northeastward towards the Great Lakes, becoming negatively-tilted into Thursday evening/night. Given the amount of pre-frontal showers and clouds, instability looks to be hard to come by, especially with the timing looking to be later in the evening into Thursday night. However, given height falls aloft and anomalous low-level moisture, 200-400 J/kg ML/SBCAPE still looks achievable. This, combined with increasing low-level flow to 50+ kts at a few thousand feet AGL (especially late at night Thursday into early Friday morning) could be enough for low-topped convection capable of bringing down damaging wind gusts or spinning up a brief tornado or two. The greatest potential for any severe weather appears to be Thursday night.
  18. yoda
    SPC AC 100551 Day 2 Convective Outlook NWS Storm Prediction Center Norman OK 1251 AM CDT Wed Apr 10 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN THE UPPER OH VALLEY AND PARTS OF THE SOUTHEAST... ...SUMMARY... Severe thunderstorms with a few tornadoes, scattered damaging winds, and isolated large hail are likely across the Upper Ohio Valley vicinity, mainly during Thursday afternoon. Scattered damaging winds and a few tornadoes will also be possible across southeast Georgia into central Florida, from Thursday morning into the afternoon. ...Synopsis... A full-latitude mid/upper trough will be centered near the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A steadily deepening surface cyclone will track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clustering into short-line segments appears likely to develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. MLCAPE should reach 500-1000 J/kg amid a meridional supercell wind profile, before low-level flow becomes veered from the southwest. Consensus of 00Z CAM guidance supports the potential for a few supercells, with some upscale growth into a line segment as convection consolidates northeastward. This may be relatively short-lived as convection outpaces the weak buoyancy plume and likely weakens after dusk. A mesoscale corridor of greater severe probabilities, seemingly in the form of damaging wind, may be warranted in later outlooks. ...Southeast GA to central FL... Extensive deep convection should be ongoing from north FL into GA at 12Z Thursday. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat during the late morning into about mid-afternoon as stronger boundary-layer heating occurs across the FL Peninsula. Large-scale ascent will subside with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. ...Carolinas and VA... Overall severe threat appears rather conditional during the daytime hours given extensive convection across at least north FL and GA on Thursday morning. Diabatic surface heating should be quite limited by abundant downstream cloudiness/weak convection north of the deeper convection during the day. Consensus of guidance largely attempts to destabilize on the backside of early-day convection within a plume of at least mid 60s surface dew points. Overall threat will probably consist of sporadic damaging winds and up to a few brief tornadoes within lower-topped convection, mainly from midday through Thursday evening. With the expectation for lesser severe weather coverage relative to areas farther northwest and south, have opted to highlight much of this region with a cat 1-MRGL this cycle. ..Grams.. 04/10/2024
  19. yoda
    Morning day 2 OTLK from SPC (no hail probs so skipped that image)
  20. yoda
    https://earthquake.usgs.gov/earthquakes/eventpage/us7000mawq/executive?utm_medium=email&utm_source=ENS&utm_campaign=realtime
  21. yoda
    Day 3 Convective Outlook NWS Storm Prediction Center Norman OK 0226 AM CDT Tue Apr 09 2024 Valid 111200Z - 121200Z ...THERE IS A SLIGHT RISK OF SEVERE THUNDERSTORMS IN PARTS OF THE SOUTHEAST AND THE UPPER OH VALLEY... ...SUMMARY... Scattered severe thunderstorms are possible on Thursday across parts of the Southeast and the Upper Ohio Valley. ...Synopsis... A full-latitude mid/upper trough should be centered near the MS Valley at 12Z Thursday, comprised of two primary shortwave impulses. The southern-stream impulse should pivot northeast and accelerate as the northern-stream impulse becomes the dominant embedded feature. A steadily deepening surface cyclone should track northeast from the Lower OH Valley to the Lake Huron vicinity during the period. ...Southeast... A convective swath should be ongoing from parts of the FL Panhandle into GA on Thursday morning. The southern portion of this activity will have the best chance to maintain a damaging wind and embedded tornado threat from late morning into the early afternoon as stronger boundary-layer heating occurs across FL. Large-scale ascent will weaken with southern extent through the day given the northeastward track of the surface cyclone, in addition to low-level winds becoming more veered in time over the FL Peninsula. Farther north, fast 850-700 mb winds should be coincident with a plume of mid to upper 60s advecting north into the Carolinas. However, diabatic surface heating may be quite limited by abundant downstream cloudiness/stratiform rain north of the deeper convection in FL. Mid-level lapse rates will also be weak and overall instability may remain meager. Still, the high-shear/low-CAPE setup with at least low-topped convection likely persisting until it progresses off the coast will foster some threat for sporadic damaging winds and a few brief tornadoes, mainly midday through early evening. How far north and how long the severe threat persists into Thursday night is unclear, but low probabilities appear warranted through at least the Lower Mid-Atlantic States. ...Upper OH Valley... A synoptically favorable corridor for a few supercells and organized clusters should develop east of the gradually deepening surface cyclone track. This region should have a period where an overspreading mid-level dry slot coincides with the diurnal heating cycle, before early afternoon convection develops within the left-exit region of the strong mid-level jet across the Southeast and southern Appalachians. While MLCAPE will remain weak, a meridional supercell wind profile should be present before low-level flow becomes veered from the southwest. A couple tornadoes, isolated to scattered damaging winds, and isolated severe hail are possible. ..Grams.. 04/09/2024
  22. yoda
    LWX AFD from this afternoon mentions the severe threat LONG TERM /THURSDAY THROUGH MONDAY/... Potent low pressure in the southern stream will begin to phase with northern stream energy as it tracks through the Midwest into the Great Lakes Thursday, before moving into Canada Thursday night into Friday. A strong cold front associated with this system will approach the area Thursday before most likely passing through late Thursday through Thursday night. A strong southerly flow ahead of the system will allow for plenty of moisture to advect into the area, causing widespread showers to develop. There will be some instability, bringing the chance for thunderstorms especially later Thursday into Thursday night (ahead of the cold front). There is still low confidence regarding how unstable it will get since clouds and rain will thwart diabatic heating, but plenty of warm and moist air will cause at least some instability. A line of heavier showers and thunderstorms may develop late Thursday into Thursday night, bringing the threat for damaging wind gusts. This will be dependent on how much instability can develop an whether or not it will be rooted within the boundary layer. Locally heavy rainfall may lead to isolated instances of flooding during this time as well.
  23. yoda
    Day 4-8 Convective Outlook NWS Storm Prediction Center Norman OK 0359 AM CDT Sat Apr 06 2024 Valid 091200Z - 141200Z ...DISCUSSION... An active severe weather pattern should persist through mid-week before diminishing towards next weekend. Primary feature of interest will be a southern-stream shortwave trough near the Southwest/Mexico border area at 12Z Tuesday. Non-GFS/GEFS guidance suggest this wave should eject east and amplify as it approaches the Lower MS Valley, before pivoting northeast ahead of a northern-stream shortwave trough digging towards the Upper Midwest. As this likely occurs, extensive convection is expected across the Gulf Coast region. Initially steep mid-level lapse rates and fast mid-level flow will support a broad severe weather area for D4/Tuesday across much of central/east TX and LA. Although mid-level lapse rates should be weaker on D5/Wednesday, the amplifying trough and resultant deepening of the surface cyclone, in conjunction with rich boundary-layer moisture, will support a continued severe threat area focused on the Sabine and Lower MS Valleys. D6/Thursday is the lower confidence forecast of the three days, given probable weak mid-level lapse rates with east/north extent. Still, there is enough signal in appreciable boundary-layer heating in the Southeast to warrant a severe area highlight within a highly sheared/weak CAPE environment. Flow fields throughout the troposphere will become quite strong across an even broader area farther north both east and west of the Appalachians. 00Z ECMWF ensemble data indicates a decent amount spread in timing/amplitude of the surface cyclone in the OH Valley/Midwest by Thursday, within a probable low CAPE environment. An area-of-interest for a future severe area highlight is evident in this region and into parts of the Northeast late Thursday or D7 Friday. ..Grams.. 04/06/2024
  24. yoda
    Good luck! My mom and sister are going up to Amherst in W NY (right by Buffalo). I have to stay here for work stuff
  25. yoda
    Well the 40s does. The clouds and rain return Wednesday
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