Area Forecast Discussion
Issued by NWS Blacksburg, VA
Issued by NWS Blacksburg, VA
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282 FXUS61 KRNK 221949 AFDRNK Area Forecast Discussion National Weather Service Blacksburg VA 249 PM EST Fri Nov 22 2024 .SYNOPSIS... Gusty northwest winds and mountain snow showers will continue through tonight and into Saturday morning. The wind and snow showers should eventually fade by Saturday night with drier and milder conditions expected for Sunday and Monday. The next chance of rain may arrive on Tuesday. && .NEAR TERM /THROUGH SATURDAY/... As of 1245 PM EST Friday... Key Messages: 1) Confidence is high for mountain snow showers through Saturday morning before fading by Saturday afternoon. 2) Gusty northwest winds will persist through Saturday. No changes to the headlines have been made. Another lobe of vorticity will pass aloft in association with a deep upper level low this afternoon. There will be a notable increase of wind in the wake of this feature as the 850 mb jet strengthens to near 60 kt, which will result in surface winds gusting up to 50 mph along the higher elevations. These winds should linger into Saturday morning but slowly fade by Saturday afternoon as the jet weakens. In addition, the lobe of vorticity will reinforce mountain snow showers from Boone to Lewisburg. The highest accumulations will occur in western Greenbrier County. Snow showers and flurries may extend further east towards the Interstate 81 corridor in southwest Virginia early tonight but with considerably lower accumulations. Similar to the winds, the mountain snow showers should gradually fade by Saturday afternoon. Temperatures will remain below normal due to the considerable cold air advection, cloud cover, and snow showers. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... As of 130 PM EST Friday... Key Messages: 1) Warming trend to follow winter storm system departure 2) Next chance of precipitation mid next week The low pressure system that has given us the windy and wintry conditions will move well out of the Mid-Atlantic by this weekend. Winds will calm down by Saturday evening and become more southwesterly due to a high pressure system to the south. 500mb heights will increase and subtle ridging over the Mid- Atlantic will bump temperatures by the start of next week. High temperatures by Monday are expected to be in the 50s and 60s. The next chance of precipitation will be towards mid-next week. Another surface low will go over the Great Lakes early next week and bring a cold front to our area. Dew points are expected to pick up towards the 40s and 50s as the front approaches. Precipitable water is also expected to reach 1" prior to the front. GFS is more aggressive in the 1000-700mb moisture advection than the EURO model, but moisture content will increase regardless. Bulk shear is impressive with conservative values of 50kts, but CAPE and lapse rates will not allow widespread organized convection. The source of force for precipitation will be due to the front itself and mountains as most of the rain is currently projected to be towards the western elevated portions of the CWA. Nevertheless, wind speeds of 10-15 kts are antcipiated as the front moves through. && .LONG TERM /TUESDAY THROUGH FRIDAY/... As of 130 PM EST Friday... Key Points: 1) Potent weather system to arrive during Thanksgiving Break 2) Be careful when traveling and stay tuned for updates Once the front mentioned in the short term forecast passes, a high pressure system will move in. Temperatures will briefly recover and increase as a result. This air mass, however, is temporary as a more potent weather system from the Great Plains will bring another chance of rain and cold weather towards the end of the forecast period. Details on this system are uncertain given how far out this system is but it is definitely something that should be on everyone`s radar (pun 100% intended) since it will be Thanksgiving Week. What can be currently derived from the models is towards the end of next week a mid level trough will extended southward and bring a potent cold front through the CWA. There is disagreement between the American and European models on the strength and southward extent of the trough. Both however suggest a tight pressure gradient after the front with strong winds. NBM has wind gusts between 20 and 30 kts and the Weather Prediction Center has also taken note and mentioned the wind threat in their forecasts. Aside from the wind concern, temperatures will tank due to a cold air advection set up between the surface and 500mb pressure levels. Wind chill values are expected to return to the 20s and even teens post front. Cloud cover shall return towards Thanksgiving and the frontal system will bring another chance of precipitation. Dew points are forecast to rise back towards the 40s and 50s and preciptable water is anticipated to reach between 1" to 1.5." Even so, it is too early to know what type of precipitation there will be, where it will be, and how much there will be. Due to this approaching weather pattern, the public is encouraged to stay attentive to updates that could impact Thanksgiving travels. && .AVIATION /18Z FRIDAY THROUGH WEDNESDAY/... As of 1245 PM EST Friday... Northwest winds will increase and become quite gusty this afternoon through tonight. Gusts of 25 to 35 knots at the surface are expected at all aviation sites, and some gusts may approach 40 to 45 knots across the higher elevations along the southern Blue Ridge. The upslope northwest flow will produce low ceilings with MVFR to IFR later tonight. In addition, mountain snow showers impact BLF and LWB this evening through tonight. Light snow showers may even reach BCB with sprinkles or possibly flurries approaching ROA early tonight. Confidence is high for poor flying weather west of the Blue Ridge by tomorrow morning as ceilings remain low with only gradual improvements during the day. While the Piedmont should reach VFR by Saturday, it is doubtful if the aviation sites to the west climb out of MVFR. The gusty northwest wind will persist through Saturday but not be quite as strong. The mountain snow showers and the gusty wind should gradually fade by Saturday evening. EXTENDED AVIATION OUTLOOK... High pressure will eventually arrive by Sunday to provide VFR conditions. Good flying weather should continue through Monday, but a cold front will arrive by Monday night into Tuesday to bring a chance of rain and MVFR ceilings. High pressure should return for Wednesday. && .EQUIPMENT... As of 1245 PM EST Friday... KFCX is back in service for this afternoon through tonight, but it will be brought back down tomorrow to continue the ongoing maintenance and repairs. Please use the following surrounding radars on Saturday: KRLX (Charleston, WV), KLWX (Sterling, VA), KAKQ (Wakefield VA), KRAH (Raleigh, NC), KGSP (Greenville- Spartanburg SC), and KMRX (Morristown TN). Observations from the KBLF ASOS are not available due to a FAA communications circuit outage. Technicians are currently working to restore service. && .RNK WATCHES/WARNINGS/ADVISORIES... VA...Winter Weather Advisory until 7 AM EST Saturday for VAZ015. Wind Advisory until 6 AM EST Saturday for VAZ007-009>020- 022>024. Winter Weather Advisory until 7 PM EST Saturday for VAZ007-009. NC...Winter Weather Advisory until 7 AM EST Saturday for NCZ001-018. Wind Advisory until 6 AM EST Saturday for NCZ001-002-018. WV...Wind Advisory until 6 AM EST Saturday for WVZ042>044-507-508. Winter Weather Advisory until 7 PM EST Saturday for WVZ042>044- 507. Winter Storm Warning until 7 PM EST Saturday for WVZ508. && $$ SYNOPSIS...PW NEAR TERM...PW SHORT TERM...CG LONG TERM...CG AVIATION...PW EQUIPMENT...PW