Forecast Discussions mentioning any of "HRRR" "RAP" "RUC13" "RUC" "RR" received at GSD on 10/12/18

Area Forecast Discussion...UPDATED
National Weather Service Fort Worth TX
920 PM CDT Thu Oct 11 2018 .UPDATE... Overall, the short term forecast is in good shape. However, updates were made to overnight and early Friday PoP/Wx grids based on latest expectations and incoming 00 UTC hi-res NWP. Generally tranquil conditions were noted this evening across much of North and Central Texas...but the increase in mid and upper level clouds signal what will likely be the end of our fair weather conditions that we`ve experienced over the past 48 hours. The aformentioned mid/upper level clouds are indicative of ongoing isentropic ascent and comparison between the 12 UTC Thu/00 UTC Fri FWD RAOB show that this lift has likely yielded an increase in moisture within the 700-850mb layer. RAP and NAM isentropic progs show continued lift through the overnight hours with several SPC HREF members indicating scattered to numerous convective elements between the 9-15 UTC Friday time frame. I`ve increased PoPs into the likely category across the Big Country and towards the Red River Valley with these factors in mind. Thunder prospects generally look low at this time owing to low amounts of instability as seen in forecast soundings and while I cannot rule out a rumble of thunder or two...the overall chances look too low to include an explicit mention of thunderstorms in the forecast at this time and rain showers should suffice. Otherwise, the rest of the short term forecast is in excellent shape and no other changes were needed. Updated products have already been transmitted. Bain && .AVIATION... /Issued 724 PM CDT Thu Oct 11 2018/ 00 UTC TAF Cycle Concerns---Rain potential at all TAF sites. MVFR potential and wind shift in the D/FW extended. VFR will prevail through the first 24 hours of the TAF with easterly winds becoming southeasterly. Speeds should remain at or below 12 knots. Lift will overspread from the Big Country and overspread the TAF sites early Thursday morning. Showers will approach from the west and hi-res guidance indicates that the rain will be widespread and I`ve prevailed showers at all TAF sites. Showers appear most probable around 12 UTC at the Metroplex and 18 UTC at Waco. With the dry air at the surface, there`s a chance for some turbulence below FL070. Showers should come to an end before Friday evening. Cigs will be between FL050 and FL070. A front will approach from the north and surface winds should turn more towards the east and possibly east-northeast around or after 00 UTC Saturday. This may necessitate a change back to north flow. These east winds coupled with abundant low level moisture should facilitate a round of MVFR...possibly IFR cigs Friday evening. For now, I`ll go with cigs around FL025, but it`s possible a lower flight condition will need to be advertised in subsequent TAFs. Bain && .SHORT TERM... /Issued 352 PM CDT Thu Oct 11 2018/ /Tonight/ The surface high pressure across the Northern Plains leading to our northeasterly winds will be moving to the east, and allow for a gradual veering of the winds overnight. The southeasterly winds will allow for better moisture to stream northward, ahead of a mid-level disturbance. As the disturbance approaches late tonight, isentropic ascent will begin to increase, leading to a gradual uptick in precipitation through the early morning hours. Given the increasing cloud cover due to the surge in moisture, low temperatures across Central Texas will not be as cool as last night. Lows are expected to be in the low 50s across the northeast, to around 60 degrees across the southwest. Hernandez && .LONG TERM... /Issued 352 PM CDT Thu Oct 11 2018/ /Friday Through Wednesday/ Low level warm advection in correlation with increasing isentropic ascent in the 305K-315K layer(or basically 700mb-850mb) will continue to modify our environment from west-east Friday/Friday night. This will be in advance of a strong shortwave disturbance exiting out of our detached upper low over the East Pacific and strong shortwave energy moving across the Central/Northern Plains into the Midwest Friday afternoon. Column moisture(PWAT) will increase quickly to 1.5-1.75 inches across a good chunk of Texas in response the the aforementioned warm advection by the end of the day. In addition, the NAM12 (not the GFS) will have a reinforcement of shallow and cooler low level airmass moving into our northern counties through the day, but this is not the main cold front we`ll be experiencing later in the weekend. The combination of these elements will result in scattered showers with the ascent from the shortwave enhancing mid level lapse rates enough for some embedded rumbles of thunder later Friday morning and lasting until the afternoon. A brief reprieve in between our lead shortwave and a strong shortwave dropping southward across the plains can be expected Friday evening, but it`s not a certainty that all outdoor events or high school football will be unaffected. Otherwise, the additional shallow frontal surge across the north and increased cloud cover and scattered precipitation will result in a wide range of temperatures for highs Friday. Highs may struggle into the 60s north of I-20/30, while warming to between 75 and 80 degrees across our far southern Central Texas counties. The weekend continues to look very wet, and even potentially stormy across Central Texas Saturday into Saturday night. Deep and intensifying warm advection/isentropic ascent occurring in advance of what will be the remnants of Eastern Pacific Hurricane Sergio will commence. The GFS looks to bomb surface cyclogenesis across the Permian Basin and Southeast New Mexico during the day Saturday, while the NAM12(and European to a slightly lesser extent) mainly forms a broad and weaker surface low off the lee of the Davis Mountains in Far West Texas. I believe with the GFS, it is likely underestimating the shallow cool surge across West Texas, along with carry low level characteristics from the Sergio`s remnants that it believes this circulation would survive the mountain ranges it will be crossing. I will be leaning with the cooler and wetter NAM12/European blend across our area, with mid level shortwave energy tracking slightly further south as Sergio`s remnants get absorbed with the northern stream energy quickly. If the GFS was to be believed, the entire area would be warm section with the bulk of showers and thunderstorms being confined north of I-20 and across the I-40 corridor from Amarillo to OKC. I just don`t believe this will be the case with the aformentioned northern stream energy digging south allowing the shallow front to move well into northern and western Texas. So what does this mean for North and Central Texas? Well, I believe a small warm sector will be confined south of I-20 where I believe if low levels can warm and destabilize enough with steepening lapse approaching from the west and increasing westerly effective bulk shear of 40-50 knots, a window for local strong to severe storms could develop in a corridor south and west of a line from Comanche, to Hillsboro, to Cameron or Hearne, maybe even further east depending on the how all these elements transition. The threat across these areas could linger well into the evening hours as southerly low level winds in the lowest 1-3km increase to, or in excess of 20 knots. IF this scenario were to evolve, that could result in a few shallow, rotating, discrete supercells across parts of Central Texas late Saturday. What needs to be stressed here is confidence on evolution, track, and timing of both surface and features aloft this weekend is not overly high and forecast changes could change if the initial surface front either stalls or drives further south than what is currently forecast. I`m sure more adjustments and changes are to come, but interests, especially those outdoor activities such as college and high school football and other events need to be vigilant. Rain chances will continue on Saturday night, as a strong upper level jet max near the Red River Valley and embedded mid level shortwave energy continues interacting with the rich moisture in place. Best chances should be from the DFW Metroplex northeast to Paris, with more scattered coverage across Central Texas. A strong cold front still appears poised to arrive later on Sunday, before clearing the area toward the Texas Coast Sunday night into Monday. Mostly scattered rain chances will occur, with the better chances along the low level convergence due to the strong cold front, especially Central Texas during this time period. Temperatures starting off mostly in the upper 50s and 60s will likely only warm into the 60s across the northwest counties, with 70s in Central Texas falling in the afternoon. For Sunday night into the early half of next week, a noticeable difference in temperatures will be noted behind the cold front and with an approaching mid level trough resulting in plenty of cloudiness and off/on post-frontal rainfall Monday into at least early Tuesday. Highs Monday may not make it out of the mid-upper 40s across the northwest, with the remainder of the area struggling into the lower-mid 50s with low level cold advection, precipitation, and zero insolation to assist in diurnal warming. If you really wanted Fall to arrive, well here ya go! Lastly and most importantly will be the potential impacts from consecutive days of rainfall later this weekend into the early half of next week. Widespread amounts of 2-4 inches and isolated amounts up to 6-7 inches will eventually begin to run off quickly due to antecedent and moist soil conditions. Though flash flooding is not expected to be a "widespread" threat, localized flash flooding will be possible. In addition, main stem rivers, especially those on the upper Trinity and Brazos basin are already responsive and run off into these tributaries will likely occur quickly after the first inch or more of rain this weekend. This will likely lead to at least minor, if not a few points seeing moderate flooding on these tributaries. It`s not going to be pleasant weather late this weekend into early next week with brisk, wet, and almost chilly conditions Sunday night through Tuesday, so prepare for it now. The unsettled pattern will continue through much of the week, but for now will keep POPs at low values until details become more clear. Highs will only modify into the 60s mid-late week. 05/ && .PRELIMINARY POINT TEMPS/POPS... Dallas-Ft. Worth 57 69 61 70 63 / 10 60 40 80 70 Waco 57 77 64 77 67 / 5 20 40 50 50 Paris 53 63 56 66 61 / 5 40 20 60 80 Denton 55 67 59 67 61 / 20 60 30 80 70 McKinney 54 65 58 67 62 / 10 60 30 70 70 Dallas 58 70 62 70 64 / 10 50 40 70 70 Terrell 55 72 60 71 65 / 5 30 40 60 70 Corsicana 57 73 62 75 65 / 0 20 40 50 60 Temple 58 79 65 80 68 / 0 10 30 40 40 Mineral Wells 56 71 60 68 60 / 20 60 40 80 50 && .FWD WATCHES/WARNINGS/ADVISORIES... None. && $$ 24/79
Area Forecast Discussion
National Weather Service Hastings NE
958 PM CDT Thu Oct 11 2018 .UPDATE... Issued at 956 PM CDT Thu Oct 11 2018 Held off on start time of precip, but it is on the way on radar. A potential frontogenetic band is setting up to the west and spreading east and perhaps will concentrate in a corridor including Kearney and Grand Island, but a tough call. && .SHORT TERM...(This evening through Friday) Issued at 351 PM CDT Thu Oct 11 2018 Aloft: Aircraft obs and RAP model dynamic tropopause analyses showed low-amplitude WSW flow over the Cntrl Plns...with a shortwave trof over the Nrn Rckys. This trof will dive SE and quickly cross the CWA during the AM Fri followed by NW flow. Surface: 1024 high pres was over Neb/KS at 20Z. This high will drift E into IA/MO tonight while a weak low and trailing sfc trof move in and cross the rgn tomorrow. Meanwhile...a warm front will form in the lee of the Rockies. Tonight: Becoming cldy. Satellite shows a large area of low clds overtaking the CWA from the SW at 20Z. These clouds will overspread the entire CWA. Light rain will develop this evening associated with large-scale ascent from the approaching trof. Clds will keep temps from being as cold as this AM. Lows will be in the upr 30s to near 40. Believe the boundary layer will remain warm enough to keep precip all rain. RAP/GFS Fcst soundings show there will be some wetbulb cooling...but the low-lvl column is fcst to saturate above frzg. The NAM does fcst the temp profile to drop to near frzg at LXN...but that is after ice leaves the cld. Amounts: Overall this will be a light rain event most places with 0.10-0.25". However...some models suggest a narrow FGEN band could be embedded with the larger rain shield. If that occurs...there could be a narrow strip of 0.50" or so. Fri: Rain in the AM with rain ending from W-E by noon...then decreasing clds from W-E late AM into afternoon. Temps will climb into the 40s/50s...still much cooler than normal. .LONG TERM...(Friday night through Thursday) Issued at 351 PM CDT Thu Oct 11 2018 A pattern change will allow temps to return to near normal next wk. Aloft: The longwave trof will remain over the Cntrl USA thru Mon. Another chunk of cold air will slide SE out of Canada...associated with an amplifying trof that will slowly cross the area Sun-Mon. Once this trof passes...weakening NW flow will prevail thru Wed with rising heights as split flow develops over the Wrn USA. Uncertainty increases next Thu and beyond. A cut-off low is fcst to be meandering over the Desert SW. Some models fcst this low to lift toward the Cntrl Plns late next week...while others suggest another trof will dig over the Nrn Plns. Surface: A warm front referenced above will move thru Fri night as a Clipper makes its way across Srn Canada. Its trailing cold front will slam thru late Sun afternoon or eve. Expect a burst of wind in CAA. Chilly and unseasonably strong high pres (possibly 1035+ mb) will slide down the lee side of the Rckys Sun and into the Srn Plns Mon. Another Canadian front (not nearly as cold) is fcst to move thru Tue...but it may just brush the area and/or quickly move E of the rgn as warm front Wed. Downslope warming should prevail Wed-Thu. Temps: A nice rebound back to near normal Sat...but then another unseasonably cold day with highs jammed in the 30s to near 40 Sun. A little recovery Mon but still way below normal...then back into the 50s Tue...and 60s Wed-Thu. Precip: A little light rain/snow is currently fcst to move thru Sat night. A small precip shield should develop (as it looks now) and there will probably be a mix of rain/snow with snow being favored as cold air rushes in. Where snow lasts the could accumulate and this conts to look like this will occur over parts of N-cntrl KS. Right now the fcst has snow changing back to rain as temps increase a bit Sun...but this may be optimistic. Once it goes to may remain all snow. This is still more than 48 hrs away...but it currently looks like 1- 2" could occur...possibly up to 3 in a few spots if it comes down hard enough. && .AVIATION...(For the 00Z KGRI/KEAR TAFS through 00Z Friday) Issued at 653 PM CDT Thu Oct 11 2018 Ceilings will gradually lower tonight as an upper trough moves through from west to east. Light to perhaps moderate rain will likely be ubiquitous late tonight into early Friday morning until the trough of the upper wave moves east. Rain should fill in outside of this band and already showing signs of this as the upper trough approaches. && .GID WATCHES/WARNINGS/ADVISORIES... NE...None. KS...None. && $$ UPDATE...Heinlein SHORT TERM...Kelley LONG TERM...Kelley AVIATION...Heinlein
Area Forecast Discussion
National Weather Service Wichita KS
944 PM CDT Thu Oct 11 2018 .UPDATE... Issued at 944 PM CDT Thu Oct 11 2018 850-700h Warm advection/moisture transport continues to increase across the TX panhandle as this time, with the latest IR satellite showing increasing mid level clouds and precip. Latest RAP and other hi-res models suggest that this warm advection will gradually increase late this evening and overnight, with saturation leading to light rain breaking out (or moving northeast) across central KS sometime after midnight. This advection is being aided by a shortwave expected to move out of the northern rockies late tonight and sweep east across the forecast area for the morning hours on Fri. As the lift associated with the shortwave increases, think the light rain showers will become more numerous by early Fri morning, and especially by sunrise Fri. As the lift increases could see some pockets of moderate rain develop, across portions of central KS and eventually across SE KS, as warm advection and lift increases. Latest model guidance suggests that instability will be limited so not expecting alot of thunder, if any at all. but will leave the mention in for now. This will thankfully limit the heavier rain potential, with most locations seeing generally a quarter of an inch of rainfall by Fri afternoon. Current timing in the grids/zones looks okay with only minor updates expected. Ketcham && .SHORT TERM...(This evening through Friday night) Issued at 312 PM CDT Thu Oct 11 2018 A broad area of high pressure is situated over the Plains states this afternoon. Beneath this high, lows this morning fell below freezing for a few of our far northwest counties thanks to lighter winds and less cloudcover. Meanwhile, the latest surface analysis suggests a weak lee-side low is beginning to develop over southwest Colorado, possibly in response to a weak PV anomaly ejecting out of the central Rockies. This low may deepen some, but a lack of more substantial height falls should keep any deepening at a minimum. East of the low, a modest LLJ will develop by this evening, with a broad area of WAA developing across much of Kansas. The increasing low-level flow should aid in quicker moisture advection with PWats nearing 1" across southern Kansas. Initially, we should see some increase in shower activity early this evening within the WAA regime. Later this evening through the overnight hours, a s/w trough will drop SE out of Montana, providing at least some enhanced lift/convergence over Kansas. This should lead to an increased coverage/intensity of the rain, with one or two bands of moderate rain developing across the area. Of note, though, the models have backed off some on the lift associated with this wave and instead of a band of moderate to heavy rain, we may end up seeing more of a broad area of light to occasionally moderate rain. Forecast soundings and hi-res guidance still suggest some banding potential with embedded thunder, but the greater potential seems to be shifting south of I-70 and east of I-135. The main takeaway here is that QPF amounts were lowered some compared to previous forecasts due to the expectation of somewhat weaker lift/convergence. That said, there is still some potential for a few locations to see over a half an inch (likely east-central through southeast Kansas). This is important because of any implication it could have on river levels/forecasts. For now, the main impact looks to be slowing the fall of rivers currently in flood, which would extend, at least briefly, the flooding impacts. Precip should quickly move out from west to east late Friday morning through Friday afternoon. Please see they "Hydrology" section for additional information on the ongoing river flooding. Martin .LONG TERM...(Saturday through Thursday) Issued at 312 PM CDT Thu Oct 11 2018 The extended portion of the forecast continues to be a complex one as we deal with the remnants of "Sergio", followed by the potential of some wintry precipitation. Tropical Storm "Sergio" has already begun to get pulled northeast by the larger-scale upper trough that extends from California to Hudson Bay. Medium range guidance continues to remain in good agreement regarding the upper level pattern and associated track of the remnants of "Sergio". As it lifts northeast, it should transition to a mid-latitude system over the Southern Plains, producing a swath of heavy rain from Texas through the Ohio Valley. Model and WPC guidance have all shifted a bit south with the axis of heavy rain and for now I see no reason to disagree with this consensus. Ultimately, this should keep QPF amounts directly associated with "Sergio" on the lower side for our CWA. As what is left of "Sergio" races east, we should begin to see a phasing of the northern and southern branches of the jet stream by Sunday. Meanwhile, an initially shallow cold front is forecast to surge south down the lee of the Rockies late Saturday into Sunday. While the exact evolution of the SFC and upper level features will continue to be refined in coming days, the latest model guidance suggests an overrunning setup could develop on Sunday. Within this setup, low-level CAA and moderate precip rates could lower temps enough for rain to mix with, or perhaps even change to, a wet snow for a portion of our forecast area. The coldest air may lag the main precip shield leading to a somewhat limited opportunity for wintry precip, but synoptically, the potential is definitely there. Given this is still 3-4 days out, confidence remains somewhat lower as the wintry potential may be very much rate- driven and dependent on how quickly the cold air arrives. Initial thought is that the best opportunity for some wintry precip will be central Kansas, roughly northwest of a Great Bend to Salina line, but the latest forecast will reflect the potential of a rain/snow mix as far south and east as the Wichita metro. Warmer ground/road temps and temperatures near/just above freezing will likely be limiting factors for any accumulation and it is too early to even speculate on potential amounts (if any occurs at all). Stay tuned... What is more certain is a shot of abnormally cold air in the wake of this system, with some records potentially in jeopardy. A widespread freeze seems plausible as well. The colder air looks to be short- lived, though, as temperatures should moderate as return flow ensues. Martin && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 711 PM CDT Thu Oct 11 2018 Expect deteriorating aviation conditions for the next 6-12 hours. A mid level disturbance will lead to rain showers moving across the forecast area late this evening through Fri morning. As the light rain moves in, expect cigs to initially drop to MVFR, first in central KS for KGBD, KRSL and KSLN and eventually for KHUT/KICT. As the showers move east to west across the area, through the morning hours on Fri, cigs will slowly to drop IFR in some locations. Some of the heavier showers may also drop vsbys briefly to MVFR as well. The system will be quick hitting with aviation conditions improving across portions of central KS (KRSL/KGBD) by Fri afternoon. Ketcham && .HYDROLOGY... Issued at 312 PM CDT Thu Oct 11 2018 The number of river flood and areal flood warnings have gone down, but significant impacts from river flooding continue. With a couple more weather systems on the horizon, water levels will be slow to recede and flooding impacts could conceivably linger through the upcoming weekend. Please continue to monitor statements for the most up-to-date information for rivers in your specific area. QPF amounts through the weekend look to be in the 0.25 to 0.75" range, with the highest amounts expected from south-central through southeast Kansas. Far southeast Kansas could potentially near or exceed 1", depending on the track of "Sergio`s" remnants. Martin && .PRELIMINARY POINT TEMPS/POPS... Wichita-KICT 46 56 40 57 / 80 80 0 40 Hutchinson 45 55 39 56 / 100 80 0 40 Newton 45 53 40 57 / 90 90 0 30 ElDorado 45 53 40 57 / 80 90 0 30 Winfield-KWLD 46 56 40 58 / 70 90 0 40 Russell 42 55 38 59 / 80 50 0 20 Great Bend 43 55 39 58 / 80 40 0 30 Salina 44 53 39 58 / 100 80 0 30 McPherson 44 53 38 57 / 100 80 0 40 Coffeyville 46 54 41 60 / 60 90 10 20 Chanute 44 51 40 58 / 70 90 10 10 Iola 44 50 39 58 / 70 90 10 10 Parsons-KPPF 45 53 41 59 / 60 90 10 20 && .ICT WATCHES/WARNINGS/ADVISORIES... None. && $$ UPDATE...Ketcham SHORT TERM...RM LONG TERM...RM AVIATION...Ketcham HYDROLOGY...RM
Area Forecast Discussion
National Weather Service Lincoln IL
844 PM CDT Thu Oct 11 2018 .UPDATE... Issued at 844 PM CDT Thu Oct 11 2018 Most of forecast is fine with clear skies and light winds. However, this means that temps may drop further than current forecast...but mainly in southeast IL. So will be updating forecast for lower temps in southeast IL, which results in more patchy frost southeast IL and more areas of frost across central part of the state. Will not be adding more counties to the frost advisory at this time. Update will be out shortly. && .SHORT TERM...(This evening through Friday) ISSUED AT 318 PM CDT Thu Oct 11 2018 Skies have cleared across most of the KILX CWA this afternoon, with partial cloudiness persisting west of the Illinois River. Any residual clouds will quickly fade away by sunset, followed by clear skies across the board through the evening hours. Meanwhile, a short-wave trough evident on 20z/3pm water vapor imagery over Montana will dive southeastward into Nebraska by dawn Friday. WAA ahead of this feature will result in increasing mid/high clouds from west to east well after midnight. Models are showing some significant timing differences...with the NAM suggesting overcast conditions arriving at KPIA as early as 09z, while the HRRR delays the clouds until later Friday morning. Will take a middle-of-the- road approach here and bring cloud cover into the Illinois River Valley by 12z/7am while areas further east remain mostly clear. Thanks to the clear skies and diminishing winds, overnight lows will bottom out in the 30s. Frost Advisory will remain in effect for locations along/north of a Danville line where readings will dip into the lower to middle 30s. Clouds will rapidly increase Friday morning, with overcast conditions expected everywhere by midday. Rain showers will develop across the S/SW by mid to late morning, then will spread further east across the remainder of central Illinois during the afternoon as the atmospheric profile slowly moistens from the top- down. Due to thick cloud cover and occasional rain showers, high temperatures will be held in the 40s. .LONG TERM...(Friday night through Thursday) ISSUED AT 318 PM CDT Thu Oct 11 2018 Once the wave passes, the showers will end late Friday afternoon and skies will partially clear Friday night. With temperatures once again dipping into the 30s, patchy frost will be likely. Sunshine and slightly warmer conditions will prevail on Saturday as high temps top out in the lower to middle 50s. A pair of short-waves will interact early next week to produce a period of unsettled weather Sunday into Monday. The southern- stream feature will spread rain across Missouri into far southern Illinois as early as Saturday night: however, this precip will remain well S/SW of the CWA until Sunday. Meanwhile the northern- stream wave will come into the picture on Sunday, resulting in increasing rain chances Sunday/Sunday night. These features will settle into the Ohio River Valley, with PoPs lingering into Monday along/south of I-70. After that, a cool/dry airmass will dominate for much of next week. && .AVIATION...(For the 00Z TAFS through 00Z Friday evening) Issued at 630 PM CDT Thu Oct 11 2018 VFR conditions will prevail rest of the night, overnight and into the morning hours. Clear skies will last through the night and into the early morning hours. However, mid clouds will begin to move into the area and overspread the TAF sites during the morning hours after 13z. Cig heights will begin to lower later in the morning to around 7kft with sprinkles possible...which is covered with VCSH. Then around noon, or early afternoon in the east, predominate rain will move into the TAF sites with MVFR cigs around 2.5kft. Winds will decrease in speed as sunsets this evening and then become light and variable for the overnight and early morning hours. Then winds will become west to northwest for the late morning to afternoon. && .ILX WATCHES/WARNINGS/ADVISORIES... Frost Advisory from 1 AM to 8 AM CDT Friday for ILZ027>031- 036>038-040>048. && $$ UPDATE...Auten SHORT TERM...Barnes LONG TERM...Barnes AVIATION...Auten
Area Forecast Discussion
National Weather Service Charleston WV
722 PM EDT Thu Oct 11 2018 .SYNOPSIS... Cold front exits east this evening. Much colder air behind the front will drop lows into the 40s tonight. Cold fronts cross Friday night, and early next week, then high pressure mid week. && .NEAR TERM /THROUGH FRIDAY/... As of 715 PM Thursday... Cold front at 23Z appears to be just to the east of the forecast area. Strong cold air advection is occurring behind the front, with a decent temperature drop observed across the area this evening, with most of the CWA in the 50s. Gusty winds behind the front will continue for at least the next several hours, but should generally slacken somewhat overnight, but remain around enough to prevent any widespread fog formation, although there will remain the very slight possibility of some patches along protected waterways. Some clearing is starting to take hold across parts of the lowlands, but generally, mountainous counties will continue to have cloud cover linger for much of the night. As of 245 PM Thursday... Cold front exits east of the Appalachians to end pcpn activity by this evening. Dry and cold airmass behind the front is evident in model dewpoints dropping into the upper 30s overnight. Downglide isentropic flow brings cold advection at the sfc. H850 temperatures drop around 3C lowlands, and into the minus 2C northeast mountains. The forecast problem of the day will be whether or not dense fog would develop over relatively warmer river waters and over areas that received rainfall overnight. Dense fog formation will be likely if the sky clears tonight. However, models show different solutions in sky cover behind the front. MOS guidance, SREF and WRFnmm suggest clear skies spreading from west to east across the lowlands overnight. However, the NAM, RAP13, and HRRR bufkit soundings keep some low level stratus developing tonight across the lowlands. Believe some light fog could develop along protected river valleys, while a gentle breeze will prevent fog from forming elsewhere. ss Friday night, and early next week, then high pressure mid week. && .SHORT TERM /FRIDAY NIGHT THROUGH SUNDAY/... As of 300 PM Thursday... An upper level trough will swing through Friday night into Saturday, bringing an area of light rain in from the west. Precip could linger into Saturday morning, especially across the northern mountainous counties of WV where enough cold air could be in place for some snow flakes mixing in across the highest ridges. The NAM is the coldest solution, with 850mb temps dropping into the -2C to -4C range by sunrise Saturday. The GFS is a bit warmer, on either side of 0C, with the ECMWF just a touch warmer than that. Did include some snow in the weather grids, but did not include any accumulation due to the warm and wet ground. High pressure will then move in for the remainder of Saturday and into Saturday night, brining clear and cool conditions. Depending on how quickly clouds arrive ahead of the next system, frost may be possible in sheltered valleys in the WV mountains Sunday morning. The GFS is the fastest bringing moisture back in early Sunday morning, while the ECMWF and NAM hold off until later in the day. Temperatures will run below normal through the short term period. && .LONG TERM /SUNDAY NIGHT THROUGH THURSDAY/... As of 300 PM Thursday... Keeping an eye on a couple features through the long term period. The first half of the work week looks to be fairly active, with several upper level waves and a surface cold front working their way through the middle Ohio River Valley and central Appalachians. Waxing and waning chances of showers are expected as these features approach and pass. Temperatures remain warm enough to keep precipitation as rain. The second half of the work week looks to be fairly quiet, with high pressure in place and another round off below normal temperatures. && .AVIATION /23Z THURSDAY THROUGH TUESDAY/... As of 720 PM Thursday... Cold front has moved east of the area, with gusty northwesterly winds taking hold. Will see somewhat of a decrease in winds overnight, generally less than 10 kts, although higher terrain will continue to keep northwesterly winds in the teen to lower 20 kt range. In addition, many lowland taf sites have improved to VFR, and should generally remain VFR for the remainder of the TAF period, however, MVFR stratus is expected to linger across the higher terrain counties through at least 15Z Friday. FORECAST CONFIDENCE AND ALTERNATE SCENARIOS THROUGH 00Z SATURDAY... FORECAST CONFIDENCE: High. ALTERNATE SCENARIOS: IFR/MVFR ceilings could last longer behind the front than currently forecast. 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 M H H H H H H H H H H L HTS CONSISTENCY H H H H H H H H H H H H BKW CONSISTENCY M H H H L M M H H H M M EKN CONSISTENCY L H M M L L H H H H H H PKB CONSISTENCY H H H H H H H H H H H H CKB CONSISTENCY M L H H H H M M H H M M AFTER 00Z SATURDAY... IFR fog possible Friday night through the weekend. && .RLX WATCHES/WARNINGS/ADVISORIES... WV...None. OH...None. KY...None. VA...None. && $$ SYNOPSIS...ARJ/MZ NEAR TERM...ARJ/SL SHORT TERM...MZ LONG TERM...MZ AVIATION...SL