Area Forecast Discussion
Issued by NWS Charleston, WV

Current Version | Previous Version | Text Only | Print | Product List | Glossary Off
Versions: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50
-- Highlight Changed Discussion --
-- Discussion containing changed information from previous version are highlighted. --
000 FXUS61 KRLX 302336 AFDRLX AREA FORECAST DISCUSSION National Weather Service Charleston WV 736 PM EDT Fri Oct 30 2020 .SYNOPSIS... High pressure crosses tonight and Saturday. A strong cold front crosses Sunday to bring an early winter chill on Monday. High pressure with moderating temperatures the balance of the week. && .NEAR TERM /THROUGH SATURDAY/... As of 730 PM Friday... Moisture fetch off the Upper Great Lakes continues to weaken at this hour with stratocumulus beginning to dissipate. Confined morning fog coverage to the most protected river bottoms with 2-5KT boundary layer flow persisting even in the early morning hours. May need to cut this back even further and potentially revisit morning lows depending on clearing trends over the next few hours. As of 450 PM Friday... Adjusted hourly temperatures down slightly initially based on observed trends. Flattened the late evening cooling curve a little based on a little more persistent stratocumulus than previously forecast. Also expanded showers originating from a moisture fetch off the Upper Great Lakes a bit further back to the west from the higher terrain. Overall, previous forecast was in good shape. As of 210 PM Friday... Amid low level northwest flow, showers were concentrated over the most favored upslope areas in north-central WV. Snow mixed in over the very highest terrain may give a thin coating before ending this evening, as high pressure cuts off the upslope flow. High pressure will lead to clear, calm conditions overnight tonight, conducive to river valley fog, as well as frost, and near to below freezing temperatures. The frost/freeze program, however, is over. Return dry downslope southeast flow around the back side of exciting high pressure will lead to abundant sunshine on Saturday, along with a milder afternoon. Central guidance temperatures looked on or close, with little change from the previous forcast. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... As of 230 PM Friday... High pressure moves off to the east allowing a stacked low pressure system associated with an upper level trough to traverse towards the area during Sunday morning. This feature will drag in a cold front which will provide some precipitation and CAA for Sunday. By early Monday morning, northwesterly flow on the backside of the front will induce upslope showers across the higher elevations, while CAA will help temperatures sink even further. Below freezing temperatures across the entire area is expected with possible teens in the highest peaks and ridges. With moisture still in place on Monday morning, due to wrap around flow, moisture will nudge into the dendritic growth zone in the higher terrain. Any showers should then turn into snow which has the potential to accumulate in the northeast mountains. With blustery winds as frontal passage takes place gusts up to 30KT are possible with slightly more intense gusts in the mountains which will cause wind chills to drop near 0F in the higher terrain. Accumulations may have difficulty on the ground with strong wind, however up to 1-2 inches should come to fruition by early Monday afternoon in certain areas until finally a high pressure ridge builds in to cut off moisture and convince accumulations to conclude. Winds relax by the late afternoon on Monday and high pressure dominates thereafter. With a very cold start to Monday, quite the opposite occurs through the rest of the week as a very subtle warming trend takes hold in the long term. && .LONG TERM /TUESDAY THROUGH FRIDAY/... As of 230 PM Friday... A very benign weather pattern will set in during the long term period with high pressure steadily protecting the area with more seasonable daytime highs and cold overnight lows due to optimal radiational cooling nights. Long range models do diverge towards the end of this period while handling an upper level feature that will provide a possibility of showers across the mountains for the weekend, however they do agree the area will remain dry during this period. && .AVIATION /00Z SATURDAY THROUGH WEDNESDAY/... As of 730 PM Friday... Stratocumulus ceilings 025-040 will slowly dissipate overnight yielding mainly clear skies by early Saturday morning. This should allow for at least areas of river valley fog near all the terminals except BKW. Boundary layer flow of 2 to 5 KTs coupled with a relatively late clearing of clouds will likely restrict significant visibility reductions to the most protected river bottoms and may limit how much fog can make it onto the terminals. For now have just included only patchy fog at PKB/HTS where confidence is lower with a couple hours of VLIFR fog near daybreak for CRW/CKB/EKN. May need to trim this back even further with the 03Z/06Z issuance depending on clearing trends. Aside from any morning fog issues, mainly clear skies prevail for the remainder of the day Saturday with winds switching around to the south 5-10KTs. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SUNDAY... FORECAST CONFIDENCE: Medium. ALTERNATE SCENARIOS: Fog may remain largely confined to river bottoms with minimal terminal impacts Saturday morning. EXPERIMENTAL TABLE OF FLIGHT CATEGORY OBJECTIVELY SHOWS CONSISTENCY OF WFO FORECAST TO AVAILABLE MODEL INFORMATION: H = HIGH: TAF CONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. M = MEDIUM: TAF HAS VARYING LEVEL OF CONSISTENCY WITH MODELS. L = LOW: TAF INCONSISTENT WITH ALL MODELS OR ALL BUT ONE MODEL. UTC 1HRLY 22 23 00 01 02 03 04 05 06 07 08 09 EDT 1HRLY 18 19 20 21 22 23 00 01 02 03 04 05 CRW CONSISTENCY H H H H H H H H H H M L HTS CONSISTENCY H H M H H H H H H H H M BKW CONSISTENCY H H H H M M H H H H H H EKN CONSISTENCY H H H H H H H H M M H L PKB CONSISTENCY H H H H H H H H H H H M CKB CONSISTENCY H H H H H H H H H H H H AFTER 00Z SUNDAY... No widespread IFR conditions expected at this time. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ SYNOPSIS...TRM/JZ NEAR TERM...TRM/JP SHORT TERM...JZ LONG TERM...JZ AVIATION...JP is the U.S. government's official web portal to all federal, state and local government web resources and services.