432 FXUS61 KRNK 081509 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 1109 AM EDT Sun Jun 8 2025 .SYNOPSIS... A frontal boundary lifts north today followed by a cold front moving west to east over the area this evening. Weak high pressure builds in for Monday before another front arrives Tuesday. && .NEAR TERM /THROUGH TONIGHT/... As of 1100 AM EDT Sunday... Key Messages: 1) Showers/storms will be scattered to numerous this afternoon and evening. A few strong/severe with damaging winds the main threat. 2) Drying out tonight. A shortwave trough currently over the Ohio Valley will track eastward today, with large-scale ascent overspreading the Mid- Atlantic states by afternoon. A moist surface air mass is present across much of the forecast area WV/VA/NC with dewpoints in the 60s. A quasi-stationary front extended from near Norfolk VA, northwest along the I-64 Corridor into central WV. This front will likely be the corridor to watch for organized deep convection as the shortwave traverses the boundary this afternoon. Considerable cloudiness from the abundance of low level moisture and weak mid-level lapse rates may limit destabilization. However, it appears likely that storms will develop off the Blue Ridge by mid afternoon and spread eastward toward the coast with greatest concentration along the stationary front where pool of near 70 dewpoints will support SBCAPE of 2000-2500 j/kg and SRH around 150 m/sx2. Fcst soundings from LYH-CHO-FVX-RIC to the coast show sufficient low and deep layer shear for supercell structures capable of damaging wind gusts, large hail, and perhaps an isolated tornado. For this afternoon and evening placed the highest probability for showers/storms along the I-64 corridor down to about highway 460 with Lynchburg-Appomattox-Buckingham-Charlotte Court House in the crosshairs for the greatest threat for severe weather within our CWA. Some of the convective allowing models suggest outflow from these storms may drift south to along the VA/NC border vcnty of Danville and South Boston late in the day before exiting the CWA and heading off toward southeast VA and eastern NC...all of which supports the Slight Risk for severe weather highlighted by the Storm Prediction center for eastern VA/NC. West of the Blue Ridge not as excited about the severe threat...thinking marginal risk at best...storms more pulse in nature. There will be showers across the western CWA, but unless there are some better breaks in the cloud cover, instability will be limited. Unless we get training of storms the flooding threat will be low, as storms should be moving 20-25 mph. Best chance of training of cells will be along the stationary front across NoVA. Temperatures today will be at or about 5 degrees above normal, warmest in the NC foothills/Piedmont with mid to upper 80s. The main front per upper pattern looks to be east of us by 2am, with showers/storms fading and ending by then. Skies clear out except lingering lower clouds in the WV/far SW VA mountains. Not a big airmass change so expect lows to stay elevated in the upper 50s to mid 60s. && .SHORT TERM /MONDAY THROUGH WEDNESDAY NIGHT/... As of 1230 AM EDT Sunday... Key Points: 1. Showers/Storms late Monday afternoon through early Tuesday, especially for western regions - locally heavy rain and storms with very gusty winds possible. 2. Lingering showers/storms, especially in the east, on Tuesday. 3. Tuesday night through Wednesday night. A look at the 7 Jun 12Z NCEP Ensemble Mean 500mb Geopotential Heights shows for Monday/Monday night a rough moving through the Great Lakes region with its axis reaching south into the Tennessee Valley. Weak ridging is expected over the Rockies. For Tuesday/Tuesday night, The trough shifts east, with its axis centered over our region by late Tuesday night. Ridging shifts east into the Plains states, and a trough/low develops over the Gulf of Alaska, and weak trough will be positioned over OR/CA. For Wednesday/Wednesday night, the trough over our region on Tuesday night shifts into the western Atlantic. Another trough progresses across Ontario/Quebec with nearly zonal flow across our region. The Gulf of Alaska low/trough deepens across the Pacific Northwest. Weak shortwave trough is depicted over the Central Plains states. An upper ridge starts to build off the SE US coast. At the surface, on Monday/Monday night, low pressure will head east across south-central Canada and reach the area of western Ontario by late Monday night. As associated trough axis, potentially with a local area of low pressure, will extend southeast to over our region. A ridge of high pressure is expected to be centered over FL. Another area of high pressure may be centered over the Southern Plains states. On Tuesday/Tuesday night the trough/low over our region shifts east to over New England, and high pressure builds into the Tennessee Valley. A broad ridge axis remains over the western Atlantic with an ridge axis over FL. For Wednesday/Wednesday night, the ridge axis over FL shifts north to over our region. To our west, low pressure and associated trough axis beings developing over the Central to Northern Plains states. A look at the 7 Jun 12Z NAEFS Ensemble Situational Awareness data shows 850mb temperatures on Monday around +16C to +18C across the region. Values decrease on Tuesday to around +14 to +16C. For Wednesday, only a small change is expected with values ranging from +15C to +16C. A look at the NAEFS Mean Integrated WV Transport shows late Monday night through Tuesday morning with values across first the southern sections of the region, and then the southeast sections of the region obtaining values within the 90 to 97.5 percentile of the 30 year CFSR climatology. The above weather patterns offer the following forecast. Active weather is expected Monday afternoon through Tuesday with the approach and passage of a cold front. With the potential of a weak area of low pressure developing along the front over or near our region, this feature could briefly stall the progression of the front across our region. This could potentially set up a scenario with locally heavy rain, or a prolonged period of rain in general, across portions of the region. In addition to the potential for showers associated with this features, thunderstorms area also expected, especially during the Monday evening period. During this time of interest, an upper trough is expected to be centered over the Great Lakes region. Its associated trough axis is expected to extend south to over the Lower Ohio Valley. On the southeast flank of this trough, a sw-ne oriented 55 to 60 kt jet streak is forecast over the region of OH/PA/NY. This would place our forecast area, especially the western sections, under this feature`s right entrance region. Coincident to the dynamics aloft, the 7 June 21Z SREF offer the following convective parameters for this location/time: MUCAPE between 1000 and 1500 J/kg, 0-3km SRH a little less than 100 s2/s2, effective bulk shear of 30 to 35 kts oriented nearly parallel that of the cold front, 700- 500mb lapse rates with <10 percent probability of being >=7C/km, DCAPE between 500 and 750 J/kg, PW around or little over 1.25 inch, and a mixed-layer LCL with a 30 to 50 percent chance of being <=1000m. The above would not only support the potential for thunderstorms, but also some with locally strong wind gusts. With the bulk shear nearly parallel to the front, shower/storm development would be more of a cluster/line development rather than cellular, leading more to a training potential, especially for western areas. While the bulk of the shower/storm activity will be Monday night into early Tuesday, lingering activity will continue on Tuesday until the axis of the upper trough moves east of the region. Coverage on Tuesday should be greatest in the east, with peak heating MUCAPE in that are still approaching 1000 J/kg along the effective bulk shear around 30kts. Tuesday night, Wednesday, and Wednesday night, the arrival of high pressure over the area will bring drier conditions. Temperatures look to be warmer than prior to the the Monday night/Tuesday cold frontal passage thanks to warm advection around the ridge axis and less cloud cover. Confidence in the above weather scenario is moderate. && .LONG TERM /THURSDAY THROUGH SATURDAY/... As of 1230 AM EDT Sunday... Key Points: 1. Warm/Hot and humid through the period. 2. Primarily rain free on Thursday into early Friday. 3. Increasing coverage of showers/storms Friday afternoon through Saturday. A look a the 7 Jun 12Z NCEP Ensemble Mean 500mb Geopotential Heights shows for Thursday/Thursday night the trough over SE Canada amplifies and extends southeast to over the Canadian Maritimes. Nearly zonal flow continues over our area. The Central Plains shortwave trough shows little movement. The ridge centered off the SE US coast holds fast. A low/trough continues to deepen and amplify over the Pacific Northwest. For Friday/Friday night little changes are expected synoptically. A trough/low remains over the Pacific Northwest. A trough/low is over southeast Canada. High pressure remains centered off the SE US coast. Additionally ridging is noted over the Northern Plains states. For Saturday, again, little change is expected synoptically as compared to Friday. About the only item of interest is a broadening of the SE Canada trough, such that our region starts to be within a northwest flow regime on the western side of this trough axis. At the surface, for Thursday/Thursday a ridge of high pressure remains over the SE US curing northeast into the Tennessee Valley. A low/trough will be situated over much of SE Canada, with the tail of this trough perhaps reaching as far south as part of the mid- Atlantic region. Another low is expected to centered south south of Hudson Bay. A general area of troughiness is expected over the Central to Southern Plains states. For Friday/Friday night, not a lot of change is expected to overall surface pattern. However, there are signs that a warm front may be developing from the Central Plains east into the mid-West. Otherwise, little change is noted for the ridge axis over much of the SE US, and the low south of Hudson Bay. For Saturday, the low south of Hudson Bay may make a shift south, and in doing so help shift the warm front over the mid- West south towards our region as a cold front. In response, the ridge axis of the SE US may make a small jog south. A look at the 7 Jun 12Z NAEFS Ensemble Situational Awareness data shows 850mb temperatures are expected to average around +17C to +18C over the region. On Saturday and Sunday, similar values are expected. The above weather patterns offer the following forecast. With the center of high pressure centered to our southeast, and an approaching trough to our west, we can expect a summer-like pattern for the region. Anticipate both warm air advection and also increasing moisture advection into the region. The result will be pattern trending increasingly warm/hot and humid through the period. For the most part, outside of a stray shower/storms, Thursday and much of Friday should be primarily precipitation-free. However, by the afternoon Friday, Friday night, and especially on Saturday, shower/storm chances will be on the increase as a frontal boundary to our south heads south, and a weak area of low pressure rides along it. Confidence in the above weather scenario is moderate. && .AVIATION /14Z SUNDAY THROUGH THURSDAY/... As of 630 AM EDT Sunday... A mix of VFR/MVFR this morning and pockets of IFR south of BLF/BCB. Scattered showers and storms to be a bit more pronounced today but the coverage to stay scattered/numerous with high concentration north of a line from LWB-LYH. At the moment will keep mostly VCTS after 16z, with a tempo group at BLF/LWB. Lesser chances toward DAN. Shower activity lacks any organization, so confidence low with respect to timing within the TAFs. Winds from the southwest to gust at times today around 20kts, and could be fairly gusty near storms. Winds turn west later this afternoon/evening and subside. Fog chances tonight appear limited due to the extensive cloud cover, but there will likely be some ridge obscuration due to some of the lower cloud bases over the mountains. Any fog and low clouds may creep back toward BLF/LWB by the end of the taf period. Later tonight low clouds and/or fog possible where it rained with higher confidence west of the Blue Ridge. EXTENDED AVIATION OUTLOOK... Expect a lull in showers Monday, then shower/storm coverage increases again Mon evening into early Tuesday. Outside of any showers/storms and late night fog anticipate VFR Monday-Tuesday. Midweek looks VFR as well with high pressure building in. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...PM/WP NEAR TERM...PM/WP SHORT TERM...DS LONG TERM...DS AVIATION...SH/WP