Area Forecast Discussion
Issued by NWS Wilmington, OH

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 FXUS61 KILN 270600 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 200 AM EDT Thu Apr 27 2017 .SYNOPSIS... A cold front will approach the region tonight and move across the area on Thursday. High pressure will briefly build in behind the front. Then conditions will become unsettled over the weekend. && .NEAR TERM /UNTIL 6 AM THIS MORNING/... A few thunderstorms may briefly edge near extreme northwestern portions of the forecast area early this evening, otherwise expect dry conditions for most of the night. Showers and isolated thunderstorms will begin to move into the region towards the end of the near term as a cold front approaches. Winds will pick up during this time as well. With southerly flow winds are only expected to drop into the 60s overnight. && .SHORT TERM /6 AM THIS MORNING THROUGH 6 PM FRIDAY/... Initial short wave will track northeast through the area during the morning. This will take scattered showers and perhaps some thunderstorms along with it. 12Z guidance has become less organized with this first round of precipitation and cannot justify anything higher than chance PoPs. Although low clouds will be left behind the precipitation, it does appear that some instability will develop as cooler temperatures aloft associated with a short wave trough spreads across the region. This may be sufficient for new development of showers and thunderstorms as a cold front crosses the area. At this point, expect activity to be scattered at most. High pressure will build in Thursday night allowing for skies to clear. Expect sufficient cloud cover to go a bit below guidance for highs Thursday while MOS seemed reasonable with lows Thursday night. && .LONG TERM /FRIDAY NIGHT THROUGH WEDNESDAY/... Friday morning is the calm before the storm, as the day starts off dry. Some weak shower activity is possible nw of I-71 Friday afternoon. Highs on Friday will range from the lower 70s in the nw to upper 70s along the Ohio River. While all models are suggesting a widespread rain event in the Ohio Valley beginning Friday night, there continues to be a large spread in the timing and placement of the heaviest QPF. Models bring a swath of convection ne into the region Friday night along a developing frontal boundary. It appears that the best chance of rain by 12Z Saturday while be across central Indiana into the Whitewater and upper Miami Valleys. The boundary tries to buckle northward on Saturday, pushing the better chance of rain to the north and northwest of the fa. Still held onto chance PoPs in case something pops in the warm sector. The region will see a wide range of highs for Saturday, with southern section making the mid 80s, while the nw counties will be held around 70 or the upper 60s due to the clouds and rain. As a deep H5 low kicks out of the Rockies on Sunday, the warm sector will expand northward. An isolated shower will be possible and highs will be in the upper 70s to lower 80s. Models have adjusted the timing of a strong cold front passage. The 12Z run now have the front around the Ohio/Indiana border around 12Z Monday. Expect a line of showers and thunderstorms late Sunday night and Monday morning with fropa. It looks like highs will be early in the day with falling temperature during the afternoon. Temperatures will be much colder behind this front for the middle of next week. Highs will be down into the 60s. Models are now suggesting that precipitation might try and develop along the Ohio River for the middle of the week. && .AVIATION /06Z THURSDAY THROUGH MONDAY/... As low pressure lifts north toward eastern Lake Superior today, a cold front will advance east across the region. Before any precipitation arrives toward the western terminals by sunrise, we first must deal with winds increasing along with a strong low level jet aloft. The strong low level jet requires at least a period of non-convective LLWS at the terminals roughly between 06Z and 12Z. For today, high resolution models/convection allowing models are really backing off on precipitation coverage ahead of the front across our western forecast area. Also, instability is expected to be fairly low this morning. As a result, just have a chance of showers for western terminals this morning. It is unclear if ceilings will lower into the MVFR category west due to lack of widespread rain. Have kept ceilings VFR. As the front moves east this afternoon, there may be enough diurnal instability for a chance of thunderstorms toward the KCMH/KLCK. Winds will be gusty with a subtle shift in wind direction from south to southwest behind frontal passage. Expect wind gusts in the 25 to 30 knot range. For tonight, front will be east of the area. Weak surface high pressure will build briefly into the middle Ohio Valley. Post frontal stratocumulus clouds should scatter through the evening with some mid and high level clouds arriving from the southwest aloft. Gusty winds should diminish fairly quick after sunset. OUTLOOK...MVFR ceilings and visibilities with a chance of thunderstorms are possible Friday night into Monday. Wind gusts to 30 kt possible Sunday through Monday. && .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS... NEAR TERM...Novak SHORT TERM... LONG TERM...Sites AVIATION...Hickman

USA.gov is the U.S. government's official web portal to all federal, state and local government web resources and services.