646 FXUS61 KRLX 222316 AFDRLX AREA FORECAST DISCUSSION National Weather Service Charleston WV 716 PM EDT Thu Oct 22 2020 .SYNOPSIS... Warm and dry conditions will continue through Friday. Cold front passes Saturday, returns as a warm front Sunday and becomes quasi-stationary. Next cold frontal passage Tuesday. && .NEAR TERM /THROUGH FRIDAY/... As of 234 PM Thursday... Trough aloft digging into the Great Lakes and Upper Midwest begins to break down the ridge of high pressure that has brought us a few days of exceptional weather. At the surface, high pressure will move to our east causing southerly low level flow to increase later tonight. Diurnal cumulus will dissipate leaving mostly clear skies this evening along with light winds which should allow valleys to decouple. The increasing southerly flow just off the surface should cause temps to level off after an early plunge, however, but I did undercut the NBM guidance in the valleys by several degrees nonetheless. Fog should be more patchy and confined to the deeper river valleys with some low clouds possibly forming on the mountain ridges due to the increasing upslope flow into the higher terrain. Friday should be another great day, although clouds will increase from the west during the afternoon with a few showers and maybe even a thunderstorm for our southeast Ohio and northeast Kentucky counties during the late afternoon. Plenty of sunshine and light southerly flow should help our WV lowlands once again top out near 80. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY NIGHT/... As of 215 PM Thursday... Starting this period a cold front coming from the west will affect the area associated with its parent surface low pressure system which is forecast to cross into the New England/Canada territory through Friday. This feature will bring a quick burst of slightly anomalously high moisture with PWATs up to 1.25 standard deviations above normal. This, combined with just enough instability and temperatures significantly above average touching near the low 80's, will fuel the possibility of thunderstorms for the Friday afternoon and into the evening mainly across the western half of the CWA. Not much rainfall is associated with this feature, maybe 1/10th of an inch or less, for a good part of the area although higher amounts will spread across west of the Ohio River as well as under any thunderstorm activity where localized higher amounts could materialize. For Saturday, some of the frontal boundary will get hung up along the mountains as high pressure builds in from the west promoting anticyclonic flow north and chances for showers during the daytime. Temperatures will take a dive to just under seasonable norms along the higher terrain with the lowlands significantly cooler, barely reaching 60 degrees. Relatively fair weather should be anticipated through the rest of this period, however that frontal boundary to the east may retrograde slightly as a warm front as upper level troughing drives in and causes flow to become southeasterly through Sunday and forecast to bring in warmer, above average, temperatures back to the region. && .LONG TERM /MONDAY THROUGH THURSDAY/... As of 215 PM Thursday... Starting Monday, a deformation band associated with an upper level trough over the midwest will close in on the area with a wave forecast to ride up ahead of it which will cause flow to back to the southwest and funnel in southerly moisture. The aforementioned trough will dig deeper as it moves into the central plains keeping the faucet of warm southerly moisture on up through midweek and beyond. This boundary will promote rain showers and possible thunderstorms through Wednesday. Temperatures drop back down to below normal on Tuesday. By early Thursday, it appears that the band will start to move through, however right now its hard to say what impacts this semi- stationary boundary will cause as far as hydro issues are concern and exactly how much moisture the feature draws in from the Gulf. The most rainfall looks like it will fall between Tuesday and Thursday when the feature should finally exit as the low slides east just to our south. There's not a whole lot of QPF amounts are in the long range forecast from WPC for us and the rain should be spread out over a decent time range, however we will have to minor this feature closely to see how the models handle it and how this event will unfold. && .AVIATION /00Z THURSDAY THROUGH TUESDAY/... As of 710 PM Thursday... VFR conditions can be expected through tonight and Friday morning with the exception of some late night/early morning fog, mainly along river valleys in and near the mountains. Friday afternoon, some showers could cause brief restrictions in southeast Ohio, northeast Kentucky, and western West Virginia. Outside of any showers, VFR conditions can be expected. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY... FORECAST CONFIDENCE: High, except medium with fog tonight. ALTERNATE SCENARIOS: Timing, density, and location of fog late tonight could vary. 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 H H HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY H H H H H H H H H H H H EKN CONSISTENCY H H H H H H H H H H M M PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY H H H H H H H H H H H H AFTER 00Z SATURDAY... IFR conditions in rain/fog possible Friday night into Saturday morning. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ SYNOPSIS...ABE/JZ NEAR TERM...ABE SHORT TERM...JZ LONG TERM...JZ AVIATION...RPY