Area Forecast Discussion
Issued by NWS Blacksburg, VA
Issued by NWS Blacksburg, VA
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793 FXUS61 KRNK 171642 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 1242 PM EDT Tue Sep 17 2024 .SYNOPSIS... Low pressure centered over the Carolinas early this morning will drift slowly northeast, staying on the east side of the southern Appalachians, which will keep a chance of rain in the area through Wednesday. The low weakens and moves offshore Thursday and Friday, lowering the probability of precipitation. Dry weather and seasonal temperatures are expected for Saturday. && .NEAR TERM /THROUGH TONIGHT/... As of 245 AM EDT Tuesday... Key message: - Isolated chance of thunderstorms along the VA/NC border this afternoon - Continued low threat of flooding today Surface low pressure staying to the south, over the Carolinas, will keep deep easterly wind across southwest Virginia, northwest North Carolina, and southeast West Virginia. The low level jet starts out at 40 to 50 knots this morning then gradually weakens to around 15 knots tonight. The onshore flow and upslope component of the wind will keep occasional rain over the area for the next 18 to 24 hours. A majority of the models hold cloud cover in across the region. A few do show breaks in the clouds over the piedmont this afternoon. if there is some heating the shear is decent and Convective Available Potential Energy could be as high as 1000 J/KG. Will keep isolated thunderstorms along the VA/NC border this afternoon. Overnight, fog and low clouds fill in, especially along and east of the Blue Ridge. Rainfall amounts as of 2AM ranged from around 0.25 inches to 1.25 inches across northern North Carolina and along the Blue Ridge Parkway south of Roanoke. Most other locations had 0.25 inches or less. Similar to the temperature trends on Monday, clouds and rain will hold down maximum temperatures. will be leaning towards 10th percentile NBM and GLAMP guidance for maximum temperatures. Lows tonight remain mild, around 10 degrees above normal. && .SHORT TERM /WEDNESDAY THROUGH FRIDAY NIGHT/... As of 235 AM EDT Tuesday... Key Messages: 1) Confidence is high for ongoing chances of showers through Thursday due to a stalled upper level low. 2) Drier weather may arrive by Friday as the upper level low finally moves eastward. An upper level low will stall over North Carolina during Wednesday and wobble slowly eastward on Thursday. The unsettled conditions should continue with chances of showers during both days. There may be a slight chance of thunderstorms in the Piedmont on Wednesday afternoon, and that chance could move west of the Blue Ridge on Thursday afternoon based on instability in model soundings. Otherwise, it will remain cloudy and cool until the upper level low moves closer to the East Coast on Thursday night. Rain chances should reduce during Friday, and skies should begin to clear as an upper level ridge builds eastward from the Plains. The ridge should shove the upper level low completely offshore by Friday night. && .LONG TERM /SATURDAY THROUGH TUESDAY/... As of 235 AM EDT Tuesday... Key Messages: 1) Confidence is moderate for drier and milder weather on Saturday. 2) A cool wedge of high pressure may return for Sunday and Monday. With an upper level ridge slowly moving eastward over the Ohio River Valley on Saturday, drier and milder conditions should return. Temperatures will rise towards normal values on Saturday with the increased sunshine. The added heat and instability could spark an isolated shower along the southern Blue Ridge during Saturday afternoon. High pressure from eastern Canada should nose southward by Sunday and could wedge against the eastern slopes of the Blue Ridge. The resulting cool wedge of northeast flow may persist into Monday across the Piedmont. There are some model disagreements regarding a low pressure system crossing the northern Plains and whether any of its moisture may reach the Appalachian Mountains by late Monday. && .AVIATION /18Z TUESDAY THROUGH SUNDAY/... As of 12:30 PM EDT Tuesday... Widespread MVFR to LIFR ceilings are expected to continue through the remainder of the afternoon and overnight hours. MVFR visibilities in light to moderate rain look to continue through the remainder of today, with IFR to LIFR Visibilities developing overnight towards the early morning hours due to fog. Gusty northeasterly to easterly winds today should diminish through the evening and overnight as the surface low continues to fill in and occlude over northern South Carolina. Light rain across the area today is expected to transition to a heavy drizzle starting overnight tonight. VFR conditions are not expected to return to any terminals during the next 24 hour period. Average confidence for ceiling, visibility, and wind. EXTENDED AVIATION OUTLOOK... Periods of sub VFR conditions are possible through Wednesday, as a low pressure system brings rain and clouds to the area. Thursday and Friday less coverage of showers is expected. VFR conditions and dry weather is expected to return on Saturday. && .EQUIPMENT... As of 135 PM EDT Monday... The Lynchburg ASOS (LYH) is still experiencing data transmission issues, mainly at night due to FAA outage. Please use caution when using data from this site, as some may be missing. No estimated date for return to full service at this time. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...None. NC...None. WV...None. && $$ SYNOPSIS...AMS NEAR TERM...AMS SHORT TERM...PW LONG TERM...PW AVIATION...AMS/EB/RCS EQUIPMENT...AS/WP