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yoda

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  1. Expected TOR too... and they mention potential discrete sups as well Mesoscale Discussion 2129 NWS Storm Prediction Center Norman OK 1211 PM CDT Thu Oct 31 2019 Areas affected...Parts of northern North Carolina...much of Virginia...western and central Maryland...south central Pennsylvania Concerning...Severe potential...Watch likely Valid 311711Z - 311945Z Probability of Watch Issuance...95 percent SUMMARY...One or more severe weather watches will likely be needed east of the Allegheny and Blue Ridge Mountains by 4-5 PM EDT. However, isolated severe storm development, including a risk for supercells, could require an earlier watch (likely tornado) issuance. DISCUSSION...Low-level and deep-layer shear are already strong to extreme across and east of the Allegheny and Blue Ridge Mountains, within deepening lee surface troughing, to the southeast of the intensifying surface cyclone now approaching Lake Erie. Despite weak mid/upper lapse rates, the northward return of seasonably moist boundary layer air (including surface dew points near 70F), coupled with boundary layer warming, is also contributing to modest destabilization across this region. Mixed-layer CAPE probably will continue to increase through the 500-1000+ J/kg range into mid to late afternoon, perhaps as far north as south central Pennsylvania. The primary increase in severe weather potential to the east of the Allegheny Mountains still appears likely to occur in association with an intensifying squall line near/just ahead of an approaching strengthening cold front, mainly during and after the 21-23Z time frame. However, it might not be out of the question that the ongoing destabilization, weakening inhibition, and perhaps forcing for ascent associated with weak warm advection, may become sufficient to support isolated to widely scattered discrete convective development in advance of the front. If this occurs, the environment will probably be conducive to supercells, which may be accompanied by the risk for tornadoes, in addition to localized strong surface gusts. ..Kerr/Grams.. 10/31/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...AKQ...CTP...LWX...RAH...RNK...GSP...
  2. 30/20 on the TOR probs and 70/30 on the WIND probs in that watch to our west
  3. URGENT - IMMEDIATE BROADCAST REQUESTED Tornado Watch Number 685 NWS Storm Prediction Center Norman OK 1245 PM EDT Thu Oct 31 2019 The NWS Storm Prediction Center has issued a * Tornado Watch for portions of Far east Kentucky Far northwest North Carolina Far northeast Tennessee Southwest Virginia West Virginia * Effective this Thursday afternoon and evening from 1245 PM until 700 PM EDT. * Primary threats include... A couple tornadoes possible Scattered damaging winds likely with isolated significant gusts to 75 mph possible SUMMARY...A thin line of low-topped convection should spread rapidly northeast this afternoon. Damaging winds from strong to locally severe wind gusts will be the primary hazard. Some intensification to the line is anticipated towards late afternoon, which should support a risk for a couple tornadoes. The tornado watch area is approximately along and 60 statute miles east and west of a line from 20 miles southeast of Bristol TN to 50 miles northwest of Elkins WV. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU5). PRECAUTIONARY/PREPAREDNESS ACTIONS... REMEMBER...A Tornado Watch means conditions are favorable for tornadoes and severe thunderstorms in and close to the watch area. Persons in these areas should be on the lookout for threatening weather conditions and listen for later statements and possible warnings. && AVIATION...Tornadoes and a few severe thunderstorms with hail surface and aloft to 0.5 inches. Extreme turbulence and surface wind gusts to 65 knots. A few cumulonimbi with maximum tops to 350. Mean storm motion vector 21045.
  4. Tornado Watch issued to our west
  5. That end up confirmed later on? Or just TWs issued by LWX?
  6. Subtropical Storm Rebekah Discussion Number 4 NWS National Hurricane Center Miami FL AL192019 1100 AM AST Thu Oct 31 2019 The storm has lost organization since yesterday with only a skeletal curved band west and north of the center. However, ASCAT just came in with 35-40 kt winds, so the initial wind speed will stay 40 kt. Weakening is anticipated today as the low moves over cool waters and into a convergent environment aloft. All of the guidance shows any remaining convection dissipating by this evening, so the storm will likely be in the graveyard in about 12 h. A general eastward track is forecast until Rebekah decomposes into a trough sometime tomorrow, at best becoming a wave along an approaching cold front. Since Rebekah is not expected to be a tropical or subtropical cyclone near the Azores, hazard information can be found in regular products issued by the Portuguese Institute for the Sea and Atmosphere (IPMA) for those islands at https://www.ipma.pt/pt/index.html. FORECAST POSITIONS AND MAX WINDS INIT 31/1500Z 40.7N 35.3W 40 KT 45 MPH 12H 01/0000Z 41.1N 32.1W 35 KT 40 MPH...POST-TROPICAL 24H 01/1200Z 41.0N 27.5W 30 KT 35 MPH...POST-TROP/EXTRATROP 36H 02/0000Z...DISSIPATED $$ Forecaster Blake
  7. BULLETIN Subtropical Storm Rebekah Advisory Number 4 NWS National Hurricane Center Miami FL AL192019 1100 AM AST Thu Oct 31 2019 ...REBEKAH LOSING ORGANIZATION OVER THE FAR NORTH ATLANTIC OCEAN... SUMMARY OF 1100 AM AST...1500 UTC...INFORMATION ----------------------------------------------- LOCATION...40.7N 35.3W ABOUT 480 MI...775 KM WNW OF THE AZORES MAXIMUM SUSTAINED WINDS...45 MPH...75 KM/H PRESENT MOVEMENT...ENE OR 70 DEGREES AT 18 MPH...30 KM/H MINIMUM CENTRAL PRESSURE...990 MB...29.24 INCHES WATCHES AND WARNINGS -------------------- Interests in the Azores should monitor the progress of Rebekah. There are no coastal watches or warnings in effect. DISCUSSION AND OUTLOOK ---------------------- At 1100 AM AST (1500 UTC), the center of Subtropical Storm Rebekah was located near latitude 40.7 North, longitude 35.3 West. The storm is moving toward the east-northeast near 18 mph (30 km/h). An eastward turn with some increase in forward speed is anticipated by early Friday. Maximum sustained winds remain near 45 mph (75 km/h) with higher gusts. The storm should weaken and become a post-tropical cyclone by this evening or early tomorrow. Winds of 40 mph extend outward up to 70 miles (110 km) from the center. The estimated minimum central pressure is 990 mb (29.24 inches). HAZARDS AFFECTING LAND ---------------------- Rebekah is forecast to be a post-tropical cyclone when it moves near the Azores in a day or so. Please see products issued by the Portuguese Institute for the Sea and Atmosphere (IPMA) for hazard information in the Azores related to Rebekah, which can found at https://www.ipma.pt/pt/index.html. NEXT ADVISORY ------------- Next complete advisory at 500 PM AST. $$ Forecaster Blake
  8. Day 1 Convective Outlook NWS Storm Prediction Center Norman OK 1112 AM CDT Thu Oct 31 2019 Valid 311630Z - 011200Z ...THERE IS AN ENHANCED RISK OF SEVERE THUNDERSTORMS PARTS OF NC...VA...WV...MD...DC...PA... ...SUMMARY... An extensive squall line of strong to severe thunderstorms is expected to develop during the late afternoon into this evening, near and east of the Appalachians from parts of New York to the Carolinas. At least a few tornadoes and scattered to widespread damaging winds are possible. ...Northeast to the Carolinas... Have upgraded peak probabilities for both wind and tornado hazards with an active period of severe weather anticipated later this afternoon into the evening. An amplifying shortwave trough now over IL will accelerate east-northeast toward the Saint Lawrence Valley through tonight toward PA/NY, while taking on a more neutral-to-negative tilt with peak 500 mb wind speeds exceeding 120 kt. Strong surface cyclogenesis is expected in advance of the amplifying trough, with a cyclone moving from OH to far southern QC by early Friday. South of the deepening cyclone, a strong cold front will sweep eastward across the Appalachians this afternoon, reaching the Atlantic coast overnight. The cold front will be the primary focus for severe thunderstorms through this evening. Northward advection of low-level moisture will continue with mid 60s boundary-layer dew points up the OH Valley west of the Appalachians and across southeast PA to coastal southern New England. Poor low to mid-level lapse rates amid widespread clouds will hinder destabilization with northern extent in the Northeast. Richer low-level moisture (upper 60s to low 70s boundary-layer dew points) and some surface heating in cloud breaks will support a confined plume of MLCAPE between 750-1500 J/kg across parts of VA into the Carolinas at peak heating. Within the warm sector, vertical shear will increase in response to the approach and deepening of the mid-level trough/surface cyclone. Long hodographs with effective bulk shear of 50-60 kt are expected, and there will also be enlarged low-level hodograph curvature for numerous rotating storms amid effective SRH of 300-500 m2/s2. Strong linear forcing for ascent along the cold front will be the primary focus for storm development, mainly east of the Appalachians later this afternoon/evening. The strong linear ascent will favor upscale growth into a squall line, though strong deep-layer shear and enough east component to storm motions should allow embedded supercell structures to persist. The modest buoyancy and very strong 850-700 mb flow will favor damaging winds as the primary threat. These could be potentially widespread within longer-tracked bowing segments. At least a few tornadoes are also anticipated with embedded supercell and mesovortex structures, particularly from central NC to central MD. The severe threat will diminish during the late evening to overnight given an increasing dearth of surface-based instability with east/northeast extent. ..Grams/Wendt.. 10/31/2019
  9. 10% TOR PROBS AND 45% WIND PROBS ON 1630 OTLK
  10. First TW of the day issued from KMRX in extreme SW VA
  11. Mesoscale Discussion 2128 NWS Storm Prediction Center Norman OK 1012 AM CDT Thu Oct 31 2019 Areas affected...Parts of eastern North Carolina...northeastern Tennessee...southwestern Virginia...far eastern Kentucky...West Virginia and southwestern Pennsylvania Concerning...Severe potential...Watch likely Valid 311512Z - 311715Z Probability of Watch Issuance...80 percent SUMMARY...A more substantial increase in potential for severe wind gusts, and perhaps isolated tornadoes, is expected with a developing line of storms during the 1-3 PM EDT time frame. One or more watches probably will be needed within the next couple of hours. DISCUSSION...Although mid/upper-level lapse rates across much of the region are more or less moist adiabatic, latest objective analysis suggests that boundary layer warming and moistening are contributing to at least weak destabilization along the western slopes of the Allegheny Mountains. Mixed-layer CAPE may not become much more than roughly 500 J/kg, but this is expected to occur in the presence of strengthening lower/mid tropospheric wind fields, as deepening of the surface cyclone (now centered near Columbus OH) proceeds more rapidly through early to mid afternoon. Model forecast soundings indicate south to southwesterly flow intensifying to 50-70+ kt, just off the surface through around 500 mb, as the strengthening surface cold front advances toward the Alleghenies. This is expected to coincide with increasing lift along/ahead of the cold front, aided by forcing for upward vertical motion ahead of a vigorous short wave trough gradually pivoting east of the the Mississippi Valley, to support an intensifying line of thunderstorms. It is possible that this may be gradually underway across parts of northeastern Tennessee through eastern Kentucky and southeastern Ohio, but a more notable increase/intensification seems more likely during the 17-19Z time frame, before gradually spreading eastward into/through the Appalachians. As convection intensifies, downward momentum transport in downdrafts will contribute to increasing potential for damaging convective surface gusts. Large low-level hodographs could also support supercell structures along and perhaps just ahead of the developing line of storms, with a risk for tornadoes. ..Kerr/Grams.. 10/31/2019 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...CTP...LWX...RNK...PBZ...RLX...GSP...MRX...JKL...
  12. 12z 3km NAM has a mean squall line/QLCS that comes roaring through the LWX CWA -- around 23z for I81 corridor... 01z along the BR... and 02z through I95 corridor
  13. lol 12z NAM throwing out PDS TOR down by EZF and and just south of Warrenton on the soundings on pivotalweather for 00z in the possible hazard type
  14. 12z NAM pushing a little harder on the potential TOR threat this evening... gets SBCAPE up to near 800 J/KG and MLCAPE near 1000 J/KG at KIAD at 00z with EHI at 3.0 and 1km SRH at 470 m2/s2. STP is 6.6 and LCLs are fairly low - under 400m
  15. Well this post aged well... there was a gem from Strasburg in Game 6 and the Nats bats came alive in both Game 6 and 7... congrats to the Nats on becoming WS Champs
  16. @high risk @Kmlwx @Eskimo Joe ENH risk on 0600 Day 1 OTLK... rather large 5% tor and 30% wind probs
  17. I would believe so... is that correct @high risk?
  18. Ton of low level shear at 00z THUR at KDCA on the 00z NAM sounding... look at the winds turn, damn... also 60kts at 900mb is yikes
  19. Seeing some SRH values approaching or exceeding 400 m2/s2 at the 1km level... hodographs are decently curved as well around 00z
  20. I hear schools are closing tomorrow
  21. So... who's staying up tonight for the 0600 SPC Day 1 OTLK at or just before 2 am? Anyone?
  22. Subtropical Storm Rebekah Discussion Number 1 NWS National Hurricane Center Miami FL AL192019 500 PM AST Wed Oct 30 2019 Cloudiness and showers associated with a small low pressure system embedded within a larger non-tropical low over the north-central Atlantic have become better organized during the day. The cyclone has a broken convective band that wraps about halfway around its eastern semicircle, with a small area of central convection near its center. The cloud tops within the convection are not particularly cold and the system is co-located with a large upper-level low, so it is initially designated as a subtropical cyclone. The intensity is assessed as 40 kt based primarily on earlier ASCAT data. It is worth mentioning that the system also has some characteristics of a tropical cyclone, since the radius of maximum winds is not very large and the system has some moderate central convection. Much like Pablo just a few days ago, Rebekah is currently rotating around a larger non-tropical low pressure system. The initial motion estimate is 080/11 kt, but an east-northeastward motion is expected later tonight. The track model spread is larger than normal and confidence in the track forecast is low, though most of the models generally show Rebekah turning back toward the east by early Friday, followed by a turn toward the east-southeast until it dissipates later this week. On the forecast track, the center of Rebekah is forecast to approach the western-most Azores early Friday as a post-tropical/extratropical cyclone. The intensity guidance unanimously forecasts that Rebekah will change little in strength during the next 24 h, though given the small size of the cyclone, some short-term fluctuations are possible tonight. Most of the dynamical models then forecast that Rebekah's convection will decrease substantially by early Friday, likely due to a combination of colder SSTs and unfavorable upper-level winds. The cyclone is therefore forecast to become post-tropical around that time, and gradual weakening is expected. Rebekah will likely dissipate by the weekend, if not sooner. Since Rebekah is not currently forecast to be a tropical or subtropical cyclone when it nears the Azores, hazard information can be found in regular products issued by the Portuguese Institute for the Sea and Atmosphere (IPMA) for those islands. FORECAST POSITIONS AND MAX WINDS INIT 30/2100Z 38.3N 40.7W 40 KT 45 MPH 12H 31/0600Z 39.0N 38.4W 40 KT 45 MPH 24H 31/1800Z 39.9N 35.0W 40 KT 45 MPH 36H 01/0600Z 39.8N 31.3W 35 KT 40 MPH...POST-TROP/EXTRATROP 48H 01/1800Z 38.9N 26.3W 30 KT 35 MPH...POST-TROP/EXTRATROP 72H 02/1800Z...DISSIPATED $$ Forecaster Zelinsky
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