Area Forecast Discussion
Issued by NWS Jackson, KY

Current Version | Previous Version | Graphics & Text | 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 FXUS63 KJKL 191840 AFDJKL AREA FORECAST DISCUSSION National Weather Service Jackson KY 140 PM EST Thu Jan 19 2017 .UPDATE... Issued at 1012 AM EST THU JAN 19 2017 Temps and dew points have been a little slow to rise this morning compared to the inherited forecast, and have updated the temperature curve in the forecast grids. Left the forecast highs alone at this point, to see if we catch up during the day. | UPDATE Issued at 700 AM EST THU JAN 19 2017 Issued a fresh set of grids mainly to remove the fog this morning and also to fine tune the T and Td grids per the latest obs and trends. These have been sent to the NDFD and web servers - along with an updated set of zones. && .SHORT TERM...(Today through Friday) Issued at 355 AM EST THU JAN 19 2017 08z sfc analysis shows an area of high pressure moving through the Ohio Valley while a warm front is moving northeast toward the area from the Lower Mississippi Valley. High clouds have spread into the area ahead of this front. These clouds have had varying thickness as they moved overhead this night and during the thinner times the eastern valleys have managed to get colder than the rest of the area. As such, readings range from the lower 40s in the far south to the lower 30s in those colder spots. Meanwhile, dewpoints are nearly matching temperatures keeping the RH high this night while winds are light. So far, though, the fog has not been too bad out there per web cams and observations. The models are in pretty good agreement aloft through the short term portion of the forecast leading to above average confidence in their blended solution. They all depict a sharp ridge moving quickly through the region ahead of a closed low strengthening over the High Plains today. This places eastern Kentucky in deep and persistent southwest flow with energy packets passing over the state ahead of the core batch that pivots through around 12z Friday. Heights then rise further over Kentucky through the day Friday while troughing remains dominant over the Plains and western portion of the country and strong ridging resumes through the Southeast. Given the fairly small model spread during the short term will favor a general blend along with a lean toward the HRRR in the near term. Sensible weather will feature another mild January day as the warm front lifts into the area. The showers that will accompany this gradually work east into this part of the state through the late afternoon and early evening hours. This will lead to soaking rains for most of the area tonight with amounts generally between a half and three quarters of an inch - though places in the far east may see little more than a quarter of an inch total. Will keep thunder out of the forecast for now on account of the lack of instability, though cannot completely rule it out given the strengthening of the upper level system. Another very warm January day can be expected Friday as the low`s track will keep winds southerly and prevent any cold air from moving into the state even as the showers depart to the northeast and we start to dry out. Record temperatures will be within reach Friday - 66 degrees at both JKL and LOZ. Used the CONSShort and ShortBlend as the starting point for most elements through the short term portion of the forecast - making only minor adjustments to raise temperatures today and Friday. Also, adjusted PoPs in the near term to allow the pcpn chances to spread in a tad quicker this afternoon nearer the Tennessee and Virginia border. .LONG TERM...(Friday night through Wednesday) Issued at 255 AM EST THU JAN 19 2017 The overall large scale pattern in the extended remains basically the same. A strong low pressure system aloft is forecast to move across the Ohio and Tennessee valley regions from this weekend through the beginning of next week. This strong system still will affect eastern Kentucky Saturday through Monday. There will be the potential for locally heavy rainfall Saturday night through Sunday night, as a strong area of low pressures move across the lower Tennessee valley. This system will keep rainfall in our area through the day on Tuesday, as it continues to strengthen and slow down during its trek towards the Mid Atlantic region. After this system passes by, a ridge of high pressure will settle over the area Tuesday night, bringing a brief period of dry weather to eastern Kentucky. A fast moving, albeit weak, disturbance aloft is forecast to move across the lower Great Lakes region on Wednesday. The weak surface boundary associated with this system may bring isolated rain showers to the area on Wednesday and Wednesday night, but these should be few and far between and should be out of the area by around dawn on Thursday. We are still expecting above normal temperatures through out the period. Especially on Saturday and Sunday, when the mercury could climb into the upper 60s on Saturday and the low to mid 60s on Sunday. Persistent southerly flow will be the cause of this jump in temperatures. The warmth will last through Wednesday, with daily highs in the 50s expected. Nightly lows will generally be in the 40s and 50s through Monday, and will be slightly cooler from Tuesday onward, as slightly cooler air filters in the area behind our departed weather system. Lows from Tuesday morning onward should bottom out around 40 each day. && .AVIATION...
-- Changed Discussion --
(For the 18Z TAFS through 18Z Friday afternoon) ISSUED AT 139 PM EST THU JAN 19 2017 Showers have started to move into the region from the southwest, and have resulted in localized mvfr visibility near the TN border at the start of the period. Elsewhere, conditions were VFR, but ceilings were showing an overall lowering trend. The increasing clouds and showers were due to a warm front approaching. Showers will overspread the rest of the region this afternoon and tonight. MVFR conditions (and perhaps some IFR in the west) will also spread northeast over more of the JKL forecast area, but the advance will be slowed over the far eastern part of Kentucky due to low level downslope wind flow. Showers will taper off with passage of the warm front from southwest to northeast overnight and early Friday morning. However, downslope flow in the east will also be lost with passage of the front, and all areas can expect MVFR conditions on Friday morning.
-- End Changed Discussion --
&& .JKL WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...HAL SHORT TERM...GREIF LONG TERM...AR AVIATION...HAL is the U.S. government's official web portal to all federal, state and local government web resources and services.