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yoda

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  1. https://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0925&yr=2025 Mesoscale Precipitation Discussion 0925 NWS Weather Prediction Center College Park MD 1025 AM EDT Wed Aug 13 2025 Areas affected...Portions of the Central Appalachians and Mid-Atlantic Concerning...Heavy rainfall...Flash flooding likely Valid 131425Z - 132025Z SUMMARY...Clusters of heavy showers and thunderstorms with locally extreme rainfall rates will tend to expand in coverage over the next several hours. Scattered areas of flash flooding will gradually become likely, and especially later this afternoon closer to the I-95 corridor of the Mid-Atlantic where an urban flash flood threat is expected to evolve. DISCUSSION...The latest satellite and radar imagery shows a band of heavy showers and thunderstorms moving into northern WV, and the latest trends show cooling cloud tops associated with this activity. This convection is associated with the southwest flank of mid-level vort energy going into the central Appalachians which is embedded within a very moist and moderately unstable environment. MLCAPE values across northern WV and western MD, and areas east of the Blue Ridge over the Mid-Atlantic, are locally on the order of 1000+ J/kg. However, the PWs are quite high and locally over 2 standard deviations above normal. In fact, the 12Z RAOB soundings from KPIT and KIAD showed PWs of 1.86 and 2.22 inches respectively with tall skinny CAPE profiles and elevated WBZ/freezing levels. This is strongly suggestive of a very efficient and tropical environment that will promote highly efficient processes for locally extreme rainfall rates that may reach well into the 2 to 3+ inch/hour range. Convection should tend to generally build in coverage over the next several hours as this vort energy advances off to the east across the central Appalachians and northern Mid-Atlantic region. This will support heavy showers and thunderstorms advancing east through central and northern WV, western MD and southwest PA in the near-term. However, as instability and convergent low-level flow becomes better established this afternoon east of the Blue Ridge and into the Chesapeake Bay region, there will likely be the development and expansion of very heavy showers and thunderstorms across much of northern VA, central to northeast MD and southern PA, including areas along the I-95 corridor from Washington D.C. to Philadelphia. The latest hires model guidance may be underplaying the rainfall potential given the level of moisture that is in place, and there will the influence of diurnal heating and orographics that will also support an uptick in coverage of showers and thunderstorms. Slow cell-motions and localized cell-training concerns coupled with locally extreme rainfall rates may support some localized rainfall totals of 3 to 5 inches. Areas of scattered flash flooding will become likely in time, and this will include an increasing urban flash flood threat near the I-95 corridor by later this afternoon. Orrison ATTN...WFO...AKQ...BGM...CTP...LWX...PBZ...PHI...RLX...RNK... ATTN...RFC...RHA...TIR...NWC...
  2. Yeah I didn't miss the humidity last week
  3. Tropical Storm Henriette Discussion Number 18 NWS Central Pacific Hurricane Center Honolulu HI EP082025 Issued by NWS National Hurricane Center Miami FL 500 AM HST Fri Aug 08 2025 Henriette has failed to produce deep convection for about 12 hours now. The latest subjective Dvorak estimates are 25 kt from JTWC and too weak to classify from SAB and PHFO. Recent objective intensity estimates range from 25 to 40 kt. An earlier ASCAT pass from 0535 UTC showed a large area of 30-33 kt vectors on the north side of Henriette. Henriette will be maintained as a 35-kt tropical storm for this advisory, but it could degenerate to a post-tropical remnant low at any time today. The cyclone is moving just north of due west at 280/15 kt. A turn to the west-northwest is expected soon as the cyclone tracks along the southwestern periphery of a subtropical ridge to its northeast. A turn toward the northwest is forecast late this weekend into early next week as Henriette becomes steered between an amplifying longwave trough northwest of Hawaii and the subtropical ridge to its northeast. The NHC track forecast is nearly identical to the previous one and is in good agreement with the tightly clustered consensus aids. Confidence remains high that Henriette will remain far to the north of Hawaii. Henriette is over 24C sea-surface temperatures (SSTs) and is embedded within a dry airmass. These cold SSTs are expected to persist along the cyclone's track for another 12 to 24 h. If Henriette doesn't generate organized convection soon, it could degenerate to a remnant low today, and this is explicitly shown in the NHC forecast Beyond 24 h, Henriette (or its remnants) will encounter progressively warmer water temperatures over the weekend, peaking around 26-27C in about 3 days. Upper-level temperatures are also expected to decrease in a couple of days as the aforementioned trough approaches Henriette, which would increase instability. These factors, along with relatively low shear, will likely allow Henriette to restrengthen later this weekend into early next week, as depicted by most of the models. The NHC intensity forecast is at the low end of the guidance envelope through 36 h, and at the high end of the guidance at 72-96 h. Beyond day 4, wind shear from the longwave trough and cooling SSTs should lead to steady weakening as Henriette moves farther into the mid-latitudes. Even if Henriette becomes post-tropical today, given the high likelihood of regeneration back into a tropical cyclone and subsequent restrengthening, NHC plans on maintaining advisories during the post-tropical phase. FORECAST POSITIONS AND MAX WINDS INIT 08/1500Z 19.7N 141.5W 35 KT 40 MPH 12H 09/0000Z 20.3N 143.7W 30 KT 35 MPH...POST-TROP/REMNT LOW 24H 09/1200Z 21.3N 146.3W 30 KT 35 MPH...POST-TROP/REMNT LOW 36H 10/0000Z 22.6N 148.7W 35 KT 40 MPH...TROPICAL CYCLONE 48H 10/1200Z 24.1N 150.9W 45 KT 50 MPH 60H 11/0000Z 25.9N 153.2W 55 KT 65 MPH 72H 11/1200Z 27.9N 155.7W 65 KT 75 MPH 96H 12/1200Z 32.3N 160.4W 65 KT 75 MPH 120H 13/1200Z 37.1N 165.1W 50 KT 60 MPH $$ Forecaster Hagen
  4. Interesting @Kmlwx https://x.com/Gio_wx/status/1953625408219271370
  5. I'll try this this month if that's okay Roger DCA: +1.4 NYC: +1.1 BOS: +0.9 ORD: +0.7 ATL: +0.9 IAH: +1.3 DEN: +1.1 PHX: +1.6 SEA: +1.8
  6. Feels sooooooo much better outside after taking our dog for a long walk
  7. Right turner? BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Baltimore MD/Washington DC 402 PM EDT Thu Jul 31 2025 The National Weather Service in Sterling Virginia has issued a * Severe Thunderstorm Warning for... Eastern Washington County in north central Maryland... Northwestern Frederick County in north central Maryland... Northeastern Jefferson County in the Panhandle of West Virginia... East central Berkeley County in the Panhandle of West Virginia... * Until 430 PM EDT. * At 402 PM EDT, severe thunderstorms were located along a line extending from Municipal Stadium to near Saint James to near Kearneysville, moving east at 30 mph. HAZARD...70 mph wind gusts and quarter size hail. SOURCE...Radar indicated. IMPACT...Damaging winds will cause some trees and large branches to fall. This could injure those outdoors, as well as damage homes and vehicles. Roadways may become blocked by downed trees. Localized power outages are possible. Unsecured light objects may become projectiles. * Locations impacted include... Hagerstown, Shepherdstown, Municipal Stadium, Robinwood, Boonsboro, Mount Aetna, Mount Lena, San Mar, Harpers Ferry, Wolfsville, Saint James, Halfway, Myersville, Cavetown, Keedysville, Funkstown, Sharpsburg, Fairplay, Chewsville, and Rohrersville. PRECAUTIONARY/PREPAREDNESS ACTIONS... For your protection move to an interior room on the lowest floor of a building. && LAT...LON 3964 7746 3939 7753 3932 7776 3946 7792 3954 7781 3965 7773 TIME...MOT...LOC 2002Z 274DEG 25KT 3964 7771 3951 7776 3944 7788 THUNDERSTORM DAMAGE THREAT...CONSIDERABLE HAIL THREAT...RADAR INDICATED MAX HAIL SIZE...1.00 IN WIND THREAT...RADAR INDICATED MAX WIND GUST...70 MPH
  8. Warned now for 70mph gusts
  9. -10 LIs... 5000 SBCAPE...
  10. Preliminary Local Storm Report National Weather Service Baltimore MD/Washington DC 148 PM EDT Thu Jul 31 2025 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 0139 PM Waterspout 2 ENE Chase 39.38N 76.34W 07/31/2025 ANZ531 MD Trained Spotter Trained spotter reports a waterspout east of Chase, MD over the Bird River moving east. && Event Number LWX2506473
  11. Preliminary Local Storm Report National Weather Service Baltimore MD/Washington DC 148 PM EDT Thu Jul 31 2025 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 0139 PM Waterspout 2 ENE Chase 39.38N 76.34W 07/31/2025 ANZ531 MD Trained Spotter Trained spotter reports a waterspout east of Chase, MD over the Bird River moving east. && Event Number LWX2506473
  12. Preliminary Local Storm Report...Corrected National Weather Service Baltimore MD/Washington DC 243 PM EDT Thu Jul 31 2025 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 0226 PM Flash Flood Gunpowder 39.41N 76.39W 07/31/2025 Baltimore MD 911 Call Center Multiple swift water rescues ongoing along Pulaski Hwy between Allender Rd. and Joppa Farm Rd. && Corrected county/state...location Event Number LWX2506475
  13. Yes it was. The report from the spotter was at 139pm per Radarscope and warning issued at 141pm
  14. Nothing is up on SPC... but weather might have canceled/delayed it
  15. Confirmed waterspout earlier in the Bird River east of Chase, MD. .. numerous swift water rescues ongoing in Bel Air
  16. I will guess it will be 2.33"
  17. Nothing really initiating in N VA yet... a couple showers/storm N of DC metro... Baltimore metro already has numerous storms
  18. Hmmm https://www.spc.noaa.gov/products/md/md1852.html Mesoscale Discussion 1852 NWS Storm Prediction Center Norman OK 1029 AM CDT Thu Jul 31 2025 Areas affected...southeastern Pennsylvania...New Jersey...Delaware...central Maryland...and adjacent portions of northern Virginia...including DC Concerning...Severe potential...Watch possible Valid 311529Z - 311800Z Probability of Watch Issuance...60 percent SUMMARY...Thunderstorms are in the process of developing, and likely to gradually intensify through 1-4 PM EDT, accompanied by increasing risk for potentially damaging wind gusts. A brief tornado might also be possible, particularly across parts of east central and southeastern Pennsylvania into central New Jersey. DISCUSSION...Perhaps aided by forcing for ascent downstream of a short wave perturbation progressing through the southern periphery of larger-scale positively tilted mid-level troughing overspreading the northern Atlantic Seaboard, thunderstorms appear to be initiating along a stalled to slow moving frontal zone, and east of a weak surface low, across the northern Mid Atlantic. This is occurring as insolation within a boundary-layer characterized by seasonably high moisture content (including mid 70s F surface dew points) erodes inhibition. Lapse rates are generally modest to weak, and the boundary layer is not forecast to become deeply mixed, due to the moisture, but profiles still appear supportive of CAPE on the order of 1000-2000 J/kg. Beneath the southern fringe of the stronger westerlies, where flow at altitudes as low as 500 mb is around 30-40 kt, deep-layer shear is strong and supportive of supercell structures, and perhaps an organizing cluster, with potential to produce strong surface gusts aided by heavy precipitation loading and evaporative cooling in downdrafts. Thermodynamic profiles appear generally warm with limited potential for severe hail. A brief tornado might not be out of the question, but low-level hodographs, particularly south of the surface front, are likely to remain generally weak. ..Kerr/Smith.. 07/31/2025 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...PHI...CTP...LWX... LAT...LON 39747713 40357698 40687612 40957453 40617390 39087505 38667600 38597718 39107734 39747713 MOST PROBABLE PEAK TORNADO INTENSITY...UP TO 95 MPH MOST PROBABLE PEAK WIND GUST...55-70 MPH MOST PROBABLE PEAK HAIL SIZE...UP TO 1.25 IN
  19. https://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0832&yr=2025 Mesoscale Precipitation Discussion 0832 NWS Weather Prediction Center College Park MD 1101 AM EDT Thu Jul 31 2025 Areas affected...Mid-Atlantic... Concerning...Heavy rainfall...Flash flooding likely Valid 311500Z - 312100Z SUMMARY...Potential for slow moving, highly efficient thunderstorms with localized 2-3"/hr rates possible. Storm interactions may allow for localized totals of 2-4" totals and likely to induce flash flooding conditions by 21z. DISCUSSION...Surface analysis and visible GOES-E imagery shows a well defined stationary front within the Long Island sound intersecting to a surface low in the Delaware Valley before entering the terrain through the Lehigh Valley into south-central PA. A secondary surface wave near MDT/THV has a sharpening Lee Trough extending southward along the lee of the Blue Ridge toward Roanoke, VA and points south. Between the boundaries through the Mid-Atlantic, very moist and building instability can be seen with sfc Tds in the mid-70s with isolated low 80s dotted throughout the area. Weak southerly, confluent flow through 700-500mb is noted in CIRA LPW layers with enhanced moisture which totals over 2" (KIAD already at 2.16" at 12z) and will be increasing toward 2.25+" into the early afternoon. MLCAPE values have reached 2000 J/kg with weak capping noted and visible imagery shows expanding Cu field across much of the area, with some weak vertical development along major ridge lines of E PA, or near the stationary front/outflow boundary intersections across N NJ. Aloft, WV shows a very strong jet streak across the St.Lawrence River Valley with broad right entrance ascent pattern across much of the Upper OH valley through central NY into the Interior of New England. The convectively enhanced shortwave continues to shear/elongate from SSW to NNE with upstream core over E OH and into confluent flow will continue, along with the right entrance ascent provide ample DPVA and ascent profiles throughout the Mid-Atlantic. Bulk shear is greater near and north of the surface front likely to result in greater cell organization but is further distanced from deepest moisture/highest Theta-E near the Chesapeake Bay into SE PA. As such, there is likely to be difference in convective activity/manner across the area. Weak convergence along the lee trough/Blue Ridge is likely to expand areas of convection westward with time as well across NW VA. South of the Lehigh Valley, 12z guidance is increasing confidence in initial convective development through the 15-16z time frame. Initial thunderstorms will be very slow moving, but have stronger/broader updrafts with 14-15Kft of warm cloud layer for highly efficient rainfall production. While inflow will be weak, it is likely to pull multiple broad columns of that 2-2.25" Total PWat air to support 2-3"/hr rates by 18z given very slow cell motions (slower further south). Storm scale interaction/cold pool generation is likely to be the dominant mode of propagation, so interactions/collisions/mergers are possible and may result in increased duration to support localized 3-4" totals. The area remains saturated with 0-40cm soil ratios over 50-60% which is in the 70-80th percentile, combine that with proximity to large urban centers with impermeable surfaces; the shear rates are likely to overwhelm ground conditions quickly and result in flash flooding conditions; a localized considerable incident of flooding is possible as well. Gallina ATTN...WFO...BGM...CTP...LWX...OKX...PHI... ATTN...RFC...RHA...TAR...NWC...
  20. 85/78 at DCA at 10am... yucky
  21. Initiation near Bel Air
  22. Area Forecast Discussion National Weather Service Baltimore MD/Washington DC 939 AM EDT Thu Jul 31 2025 .SYNOPSIS... A cold front will slowly move across the mid-Atlantic today through Friday. Strong high pressure will build into the area over the weekend, bringing below normal temperatures and humidity. High pressure weakens into next week while the next front is expected to slowly approaches from the south. Rain chances return by the middle of next week. && .NEAR TERM /THROUGH FRIDAY/... Excessively humid conditions are being observed across the region with dew points well into the 70s to near 80 and PW in excess of 2 inches (even 70+ Tds over the higher terrain). This will fuel thunderstorms with very heavy rain beginning in a few hours (roughly midday onward). A cold front will sag south into our region today. A strong shortwave trough will move over our area this afternoon and evening. A persistent southerly flow will provide deep tropical moisture to help fuel numerous heavy showers and strong to severe thunderstorms this afternoon and evening. Dewpoint temperatures in the low to mid 70s will result in revealing PWATs of 2.2 to 2.3 inches. One final day of hot and humid conditions today with the developing convection. Highs are forecast to be in the upper 80s to low 90s, with peak heat indices between 95-105.
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