MN Transplant Posted August 3 Share Posted August 3 7 minutes ago, yoda said: Preliminary Local Storm Report National Weather Service Baltimore MD/Washington DC 538 PM EDT Sat Aug 03 2024 ..TIME... ...EVENT... ...CITY LOCATION... ...LAT.LON... ..DATE... ....MAG.... ..COUNTY LOCATION..ST.. ...SOURCE.... ..REMARKS.. 0445 PM Tstm Wnd Dmg Hume 38.83N 78.00W 08/03/2024 Fauquier VA Emergency Mngr County emergency manager reported numerous trees down, a roof blown off a house and a shed collapsed in the area of Hume Rd and Leeds Manor Rd, and northeast towards I-66. && Event Number LWX2403697 Side note, Leeds Manor is one of the best drives in the state. 1 Link to comment Share on other sites More sharing options...
Lucketts Posted August 3 Share Posted August 3 Getting hit with a 3rd t-storm now. Power still out here. 2 Link to comment Share on other sites More sharing options...
MN Transplant Posted August 3 Share Posted August 3 Very impressed with the outflow. The winds are loud in the trees. Radar is optimistic with the storms firing from Fairfax to Manassas. 4 Link to comment Share on other sites More sharing options...
frd Posted August 3 Share Posted August 3 Cell between Elk Neck to its East, and Hance Points Estates to its NE, is getting stronger . 1 Link to comment Share on other sites More sharing options...
Kmlwx Posted August 6 Author Share Posted August 6 If only we were in S PA. CSU MLP and SPC seem decently enthusiastic about their odds for severe t'storms today. 3 Link to comment Share on other sites More sharing options...
batmanbrad Posted August 7 Share Posted August 7 so far SPC isn't too bullish on the potential tornado (or even overall severe) potential for Friday, though still time for that to change with the ever-evolving track forecast updates on Debby. Much of the subforum is in MRGL risk zone for now. From the early morning D3 outlook: ...Northern Mid Atlantic... Despite the weakening trends to Debby, models suggest that the evolution of sizable clockwise-curved low-level hodographs and appreciable boundary-layer buoyancy may be maintained into at least Friday afternoon, focused in a sector to the northeast of the accelerating surface low. It appears that this may be in the process of overspreading the Chesapeake/Delmarva vicinity as daytime heating contributes to boundary-layer destabilization, before spreading northward through the northern Mid Atlantic in advance of the more inhibiting mid-level warm core. Within this environment, the evolution of a few supercell structures posing a risk for tornadoes appears possible, before this threat wanes with the loss of daytime heating Friday evening. Link to comment Share on other sites More sharing options...
yoda Posted August 14 Share Posted August 14 Don't know if this got mentioned earlier but Day 3 will now have a morning and afternoon update 3 Link to comment Share on other sites More sharing options...
George BM Posted August 17 Share Posted August 17 The 12z hrrr was fairly aggressive with CAPE for tomorrow afternoon (locally 2000+ J/kg MLCAPE) with good looking sim-radar across a good portion of the area. SPC has upgraded the immediate DC suburbs eastwards to a SLGT for tomorrow as well. 6 Link to comment Share on other sites More sharing options...
CAPE Posted August 17 Share Posted August 17 From Mount Holly AFD- A brief lull is possible late morning/early afternoon, though isolated to scattered showers and storms will remain possible during this time. Our second round of heavy rain and storms for the day looks to begin forming across eastern PA during the early/mid afternoon as the cold front associated with this system begins its eastward trek across the region. At this time, the upper level trough will begin to dig and support increased baroclinic forcing along the front. Dew points will rise into the low to mid 70s with PWATs over 2.0 inches ahead of this line of storms. As a result, rainfall forecasts of widespread 1-3 inches total are expected with local amounts of 4 inches or more possible. With this in mind, a Flood Watch was issued for the I-95 corridor and areas north & west into the Lehigh Valley and Berks County. Additionally, though daytime heating will be limited, there is a bit of uncertainty if there will be any breaks in the clouds. If any amount of daytime heating does occur, instability and lapse rates could jump and increase the severe potential for the afternoon and evening. Still a lot of uncertainty with this potential to form, but with deep layer shear around 30kts, parameters could become sufficient to support severe thunderstorms with the best conditions across southern NJ and the Delmarva. SPC has placed this region into a Slight Risk (2 of 5) for severe weather. High temperatures in the afternoon look to be in the low-80s. 4 Link to comment Share on other sites More sharing options...
Kmlwx Posted August 18 Author Share Posted August 18 DC jackpot on the CSU MLP for today 6 Link to comment Share on other sites More sharing options...
Eskimo Joe Posted August 18 Share Posted August 18 Last two runs of the HRRR try to run an UHI track from Olney up through Pikesville. . . Link to comment Share on other sites More sharing options...
nw baltimore wx Posted August 18 Share Posted August 18 14 minutes ago, Eskimo Joe said: Last two runs of the HRRR try to run an UHI track from Olney up through Pikesville. . . You know that’s wrong. Link to comment Share on other sites More sharing options...
Eskimo Joe Posted August 18 Share Posted August 18 5 minutes ago, nw baltimore wx said: You know that’s wrong. Yup. Kind of surprised there's a flood watch honestly. The storm mode seems rather progressive today. 1 Link to comment Share on other sites More sharing options...
high risk Posted August 18 Share Posted August 18 1 hour ago, Eskimo Joe said: Yup. Kind of surprised there's a flood watch honestly. The storm mode seems rather progressive today. Would only take about 1" in an hour to cause problems in parts of the area, per flash flood guidance. That seems achievable, even if storms are progressive. Link to comment Share on other sites More sharing options...
RDM Posted August 18 Share Posted August 18 19 minutes ago, high risk said: Would only take about 1" in an hour to cause problems in parts of the area, per flash flood guidance. That seems achievable, even if storms are progressive. Interesting chart - thanks for sharing High Risk. Assume because there is a valid date for the map, it takes into account recent precip, soil type, terrain etc - yes? Just curious. Don't recall seeing that map before. Link to comment Share on other sites More sharing options...
high risk Posted August 18 Share Posted August 18 30 minutes ago, RDM said: Interesting chart - thanks for sharing High Risk. Assume because there is a valid date for the map, it takes into account recent precip, soil type, terrain etc - yes? Just curious. Don't recall seeing that map before. Yes, the labeling shows that the product covers today, and it absolutely does include recent precip and accounts for the fact that some areas can achieve flash flood risk more than others (independent of recent precip). 1 Link to comment Share on other sites More sharing options...
yoda Posted August 18 Share Posted August 18 Severe Thunderstorm Watch coming soon https://www.spc.noaa.gov/products/md/md1943.html Mesoscale Discussion 1943 NWS Storm Prediction Center Norman OK 1209 PM CDT Sun Aug 18 2024 Areas affected...southeast New York...New Jersey...eastern Pennsylvania...Maryland...and northern Virginia. Concerning...Severe potential...Watch likely Valid 181709Z - 181845Z Probability of Watch Issuance...80 percent SUMMARY...Strong to severe thunderstorms are likely this afternoon and evening. A severe thunderstorm watch will be issued by mid-afternoon. DISCUSSION...Thunderstorms have started to develop across the Appalachians from central Pennsylvania into southern New York as cold-air advection aloft overspread the region. Farther east, some inhibition remains across eastern Pennsylvania amid broken cloudcover. However, this stratus deck has started to erode and should allow for significant surface heating over the next 1 to 2 hours. Under the influence of weak height falls and cyclonic flow aloft, expect scattered thunderstorm development within the uncapped environment from eastern Pennsylvania to eastern Virginia. 20 to 25 knots of effective shear (per RAP forecast soundings) will support some multicell organization with a primary threat from downbursts. An additional round of storms is possible this afternoon/evening as storms which develop over the mountains move into the lower elevations with some congealing into one or more linear segments possible. ..Bentley/Hart.. 08/18/2024 ...Please see www.spc.noaa.gov for graphic product... ATTN...WFO...OKX...ALY...PHI...BGM...AKQ...CTP...LWX... 2 Link to comment Share on other sites More sharing options...
nj2va Posted August 18 Share Posted August 18 Also have a Precipitation Meso discussion: https://www.wpc.ncep.noaa.gov/metwatch/metwatch_mpd_multi.php?md=0898&yr=2024 2 Link to comment Share on other sites More sharing options...
yoda Posted August 18 Share Posted August 18 Severe Thunderstorm Watch until 10pm https://www.spc.noaa.gov/products/watch/ww0634.html URGENT - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Watch Number 634 NWS Storm Prediction Center Norman OK 200 PM EDT Sun Aug 18 2024 The NWS Storm Prediction Center has issued a * Severe Thunderstorm Watch for portions of District Of Columbia Delaware Central and Eastern Maryland New Jersey Southeast New York Eastern Pennsylvania Northern Virginia Eastern Panhandle of West Virginia Coastal Waters * Effective this Sunday afternoon and evening from 200 PM until 1000 PM EDT. * Primary threats include... Scattered damaging wind gusts to 70 mph likely Isolated large hail events to 1.5 inches in diameter possible SUMMARY...Scattered thunderstorms will increase in coverage through the afternoon across the watch area. The more intense storms will pose a risk of locally damaging wind gusts and hail. The severe thunderstorm watch area is approximately along and 85 statute miles east and west of a line from 55 miles east of Charlottesville VA to 40 miles east northeast of Wilkesbarre PA. For a complete depiction of the watch see the associated watch outline update (WOUS64 KWNS WOU4). 1 Link to comment Share on other sites More sharing options...
CAPE Posted August 18 Share Posted August 18 BULLETIN - IMMEDIATE BROADCAST REQUESTED Severe Thunderstorm Warning National Weather Service Mount Holly NJ 319 PM EDT Sun Aug 18 2024 The National Weather Service in Mount Holly NJ has issued a * Severe Thunderstorm Warning for... Central Sussex County in southern Delaware... * Until 400 PM EDT. * At 319 PM EDT, a severe thunderstorm was located near Millsboro, or near Georgetown, moving northeast at 20 mph. HAZARD...60 mph wind gusts and quarter size hail. SOURCE...Radar indicated. IMPACT...Minor damage to vehicles is possible. Wind damage to roofs, siding, trees, and power lines is possible. * Locations impacted include... Georgetown, Millsboro, Milton, and Henlopen Acres. Link to comment Share on other sites More sharing options...
ge0 Posted August 18 Share Posted August 18 Nice storm in Berryville. pea sized hail, strong winds. Some flooding 1 Link to comment Share on other sites More sharing options...
AlexD1990 Posted August 18 Share Posted August 18 Barely even got sprinkles from the earlier storms. Yawn.Sent from my SM-F711U using Tapatalk 1 Link to comment Share on other sites More sharing options...
vastateofmind Posted August 18 Share Posted August 18 15 minutes ago, AlexD1990 said: Barely even got sprinkles from the earlier storms. Yawn. Yeah...the Stanardsville to Culpeper line completely fizzled out here in NoVA over the past 1-2 hours. Second line back in the valley...looks pretty on radar right NOW, but I'm not gonna count on that NOT holding together until it gets here. Honestly...that "watch" light on my wx radio really needs to outen itself right now. Link to comment Share on other sites More sharing options...
nw baltimore wx Posted August 18 Share Posted August 18 9 hours ago, Eskimo Joe said: Last two runs of the HRRR try to run an UHI track from Olney up through Pikesville. . . 8 hours ago, nw baltimore wx said: You know that’s wrong. 3 Link to comment Share on other sites More sharing options...
Eskimo Joe Posted August 19 Share Posted August 19 1 3 Link to comment Share on other sites More sharing options...
ge0 Posted August 20 Share Posted August 20 Was driving down Trappe Rd. the other day and stumbled on what appears to be some tornado damage from the Middleburg-Bluemont tornado during Debby 10 Link to comment Share on other sites More sharing options...
yoda Posted August 26 Share Posted August 26 Hmmm... from this mornings 0600Z SPC OTLK disco. Granted it's 0/0/5... but... ..Portions of New England into the Mid Atlantic... A 500 mb impulse/speed max will pivot around the backside of the mid-level trough and overspread portions of the Hudson Valley today, encouraging convective initiation in two zones. First, scattered multicells and perhaps transient supercells should initiate over New England and track southeast toward Cape Cod and Long Island through the afternoon. The stronger mid-level flow will contribute to straight/elongated hodographs and accompanying 30-40 kts of effective bulk (speed) shear. Strong gusts and large hail will accompany the stronger storms. The best chance for any severe wind/hail will be over southern New England, where over 1000 J/kg MLCAPE may overlap the stronger vertical shear to support stronger, longer-lived updrafts. Secondly, a cluster of multicellular/supercellular storms may develop ahead of the 500 mb speed max over the central Appalachians and track southeast toward the Atlantic Coast. Given modest low-level lapse rates and hodograph elongation, strong wind gusts may accompany these storms as well. 5 Link to comment Share on other sites More sharing options...
midatlanticweather Posted August 27 Share Posted August 27 I take it tomorrow is a stretch. Not looking very probable - ...Mid-MS/OH Valleys to the Mid-Atlantic... Uncertainty remains this forecast cycle, particularly from around central PA eastward to the northern Mid-Atlantic Coast/Chesapeake Bay vicinity. Severe thunderstorm probabilities have been focused along and just ahead of a southward sagging cold front and instability gradient from central OH to the NJ coast. Rich boundary-layer moisture (dewpoints in the upper 60s to mid 70s F) will contribute to a corridor of MLCAPE around 2000-4000 J/kg from the Mid-MS Valley eastward to the NJ coast. Warm midlevel temperatures may lead to lingering inhibition, particularly across eastern portions of the Slight and Marginal risk areas. Height falls associated with troughing over eastern Canada will remain well north of the region, and resulting in somewhat nebulous large-scale ascent amid very modest vertical shear (effective shear magnitudes generally less than 25 kt). Convection from the Day 1/Tue period may be ongoing Wednesday morning across parts of the Great Lakes vicinity and shift east along the instability gradient/southward-sagging surface front through the afternoon. Vertical shear may be locally enhanced with any MCV that may be present with this activity, and damaging winds are possible as the downstream boundary layer destabilizes. Additional isolated thunderstorm development is possible from central PA/northern VA eastward to the coast. This activity could produce locally damaging gusts and perhaps small hail if capping can be overcome and longer-lived updrafts develop. Weak shear further west toward the Mid-MS Valley vicinity will likely preclude a more organized severe risk. However, strong heating amid the very moist/unstable airmass will support isolated strong/locally damaging gusts during the afternoon. Link to comment Share on other sites More sharing options...
yoda Posted August 29 Share Posted August 29 1 hour ago, George BM said: This mornings convection appears to be developing off of an EML between ~850-750mb. 750mb fits pretty closely with where the cloud bases have been. (8,000+ft) 35 minutes ago, Eskimo Joe said: SPC mesoanalysis definitely has a bit of a remnant EML overhead. 1630z OTLK from SPC just added SLGT risk for most of us 2 Link to comment Share on other sites More sharing options...
midatlanticweather Posted August 29 Share Posted August 29 40% chance of a watch Mesoscale Discussion 2028 NWS Storm Prediction Center Norman OK 1220 PM CDT Thu Aug 29 2024 Areas affected...central Pennsylvania into western and central Virginia Concerning...Severe potential...Watch possible Valid 291720Z - 291915Z Probability of Watch Issuance...40 percent SUMMARY...Scattered storms will develop from central Pennsylvania southwestward along the Blue Ridge, with locally strong to damaging gusts possible into surrounding areas to the east later today. DISCUSSION...A moist and unstable air mass is in place today south and west of the New England surface ridge, and despite slow drying from the east. Visible imagery clearly indicates a very moist air mass with expansive cumulus fields over much of PA and southwestward along the Blue Ridge. GPS PWAT sensors show values of 1.75-2.00" from eastern VA/DelMarVa northwestward into central PA. Continued heating will lead to accelerated development over the higher terrain of eastern WV and western VA over the next few hours, with additional activity expected over much of central PA where weak convergence exists. Shear will remain weak over most of the area, with propagating clusters of storms expected to move east/southeast into the remainder of central and northern VA and parts of MD. Locally damaging gusts will be possible given the favorable timing of the development with peak heating, and as outflow pushes into regions with steep low-level lapse rates later this afternoon. 1 Link to comment Share on other sites More sharing options...
Recommended Posts
Create an account or sign in to comment
You need to be a member in order to leave a comment
Create an account
Sign up for a new account in our community. It's easy!
Register a new accountSign in
Already have an account? Sign in here.
Sign In Now