Area Forecast Discussion
Issued by NWS Wilmington, OH

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000 FXUS61 KILN 181750 AFDILN Area Forecast Discussion National Weather Service Wilmington OH 1250 PM EST Wed Jan 18 2017 .SYNOPSIS... High pressure will move in today. Low pressure traveling to the Great Lakes will bring showers back into the forecast late Thursday into Friday. Mild and mainly dry weather is expected Saturday in the southerly flow behind the low. && .NEAR TERM /UNTIL 6 PM THIS EVENING/... Latest satellite loop is showing a couple of breaks in the otherwise expansive low clouds. Expect this to continue this afternoon into this evening. So backed off on the clearing skies from the sw that was previously forecast. Temperatures will have a hard time rising today, with the caa and lack of solar insolation. Lowered highs in west central OH to the upper 30s, then allowed a gradual increase to the mid 40s in nrn KY. && .SHORT TERM /6 PM THIS EVENING THROUGH FRIDAY/... High pressure moving across Kentucky to West Virginia should keep dry weather over the ILN area tonight through early Thursday. Skies will probably remain partly to mostly cloudy with low level moisture persisting under an inversion around the periphery of the high. Low pressure developing to the west on Thursday will move up the flank of an upper ridge to the vicinity of Chicago by Friday morning. A stream of moisture carried by a 35 knot low level jet will be lifted on the warm conveyor belt ahead of the low, producing widespread rain. Models indicate around a half an inch of rainfall with this event. The rain will end Friday morning as the low weakens and redevelops over the northern plains. A relatively dry southerly flow in the wake of the low, coupled with above normal geopotential heights and weak forcing aloft, should result in dry weather conditions Friday afternoon. Temperatures will exhibit an upward trend in this warm advection regime, with highs mainly in the lower 50s Thursday, increasing to the mid and upper 50s Friday. These anomalously high temperatures will be occurring when normal highs are in the mid and upper 30s. && .LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/... In the wake of Fridays closed low there will be a brief period of subsidence on the backside of the PV, but the main question is how quickly will the precipitation return. Overall ridging begins to setup across eastern Canada and the northeastern United States with an upper level trough over the western United States. The pattern will be messy though as multiple waves of mid-level energy can be found in the flow. The GFS is slightly further east with an upper level low pushing north on the western side of the mid-level ridge. As this occurs the ridge will slowly start to move east. The GFS is slightly stronger with this low Saturday and tries to bring in precip to the area Saturday afternoon across the western zones. The CMC looks similar to the GFS while the ECMWF is slightly weaker with the energy Saturday. Looking at forecast soundings on the GFS for Saturday shows dry air between 850 and 700 mb which would favor a later onset of precipitation. Given the above have trended the forecast towards the ECMWF solution and kept Saturday drier. Sunday, another stronger piece of energy will push east across the southern United States and wrap up into an upper level low. As this happens a wedge of PV will push northeast ahead of the low and move across the ILN forecast area. PWATs at this time again rise to around 1.00". Forecast soundings on the GFS show some dry air trying to remain in various levels of the sounding at this time so have kept PoPs at chance. Seeing how strong the upper level lift currently looks on the ECMWF and GFS Sunday, PoPs will probably have to be raised. Sunday into Monday the upper level low will drift overhead keeping the clouds and a chance of rain in the forecast. It should be noted that the low looks to be vertically stacked with dry air entrained. This means that a break in the precip will probably occur sometime on Monday (possibly in the morning) but given this is day 7 have just broad brushed the PoPs at this time. On Tuesday the upper level low will slowly drift east taking the rain and precipitation with it. && .AVIATION /18Z WEDNESDAY THROUGH MONDAY/...
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MVFR/IFR cigs will linger through much of the taf period. Latest satellite loop is showing low clouds back into IL and down into TN. As H5 ridging builds into the region tonight along with a weak sfc high, the low level moisture will start to thin. Lingered the low cigs until after 06Z, then slowly scattered them out from s to n. Some mvfr fog could develop as the low clouds scatter out. High clouds will already be on the increase ahead of the next weather system. VFR conditions are expected after any morning for dissipates. OUTLOOK...MVFR/IFR ceilings are again possible Thursday night into Monday.
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&& .ILN WATCHES/WARNINGS/ADVISORIES... OH...None. KY...None. IN...None. && $$ SYNOPSIS...Coniglio NEAR TERM...Sites SHORT TERM...Coniglio LONG TERM...Haines AVIATION...Sites is the U.S. government's official web portal to all federal, state and local government web resources and services.