204 FXUS63 KILX 230117 AFDILX Area Forecast Discussion National Weather Service Lincoln IL 817 PM CDT Sun Mar 22 2020 .SYNOPSIS... Issued at 243 PM CDT Sun Mar 22 2020 Snow, or mix of rain and snow, will diminish across the area tonight. Light accumulations less that one inch are possible on grassy and elevated surfaces. High pressure will bring quiet weather to the state on Monday, though skies will remain cloudy. && .UPDATE... Issued at 807 PM CDT Sun Mar 22 2020 Back edge of the precip stretches from roughly Havana to Danville this evening with only a couple patches of drizzle or flurries further south. Water vapor imagery does show a pronounced dry slow cutting across portions of central Illinois, and some locations have been reporting rain/drizzle as ice nuclei are lost from the column. As the chance for accumulating snow ends, there may be a brief transition to a wintry mix before precip ends altogether. Precip should end across central Illinois between 200 and 400 am in the morning. Any accumulations will be very light, less than an inch, and confined to the grass and a few elevated surfaces. && .SHORT TERM...(This evening through Monday) ISSUED AT 243 PM CDT Sun Mar 22 2020 Zone of enhanced isentropic lift is beginning to shift east of the area this afternoon, and water vapor imagery shows drier air moving in from the southwest. Lift was strong enough this morning to produce a heavier burst of snow which overcame marginal surface temps to produce 1-2" amounts in Sangamon Co. However as snowfall rates have decreased and temperatures hold around 32-35 degrees, most of the snow falling now is melting as it hits the ground. Expect decreasing snow intensity and coverage from the southwest late this afternoon, except in the northwest CWA where another round of forcing associated with the mid level shortwave moving through southern IA, could produce some light accumulations through this evening. Generally an inch or less expected for the remainder of this event, north of a Canton to Bloomington line, diminishing by midnight. Farther south, any lingering areas of light rain or snow to end this evening. Lows tonight to be held up by remaining cloud cover, falling only a couple degrees from this afternoons readings. For Monday, 1025 mb high pressure builds across the state and brings one of the few periods of quiet weather this week. Forecast soundings indicate moisture to remain trapped under the subsidence inversion, leading to a continuation of low clouds. As a result, have trended highs towards cooler guidance primarily in the mid 40s, except lower 50s south of I-70. .LONG TERM...(Tuesday through Sunday) ISSUED AT 243 PM CDT Sun Mar 22 2020 The next system emerging from the active southern jet stream, will spread rain back into the region Tuesday morning. EC continues to be a southern outlier, tracking 1000 mb surface low along the Ohio Valley. Other guidance suggests a farther north track towards our southern CWA, which could potentially place areas south of I-70 in or near the warm sector. This would carry a conditional severe weather threat Tuesday afternoon/evening, with several hundred Joules of MLCAPE and modest deep layer shear. SPC Day 3 outlook places a marginal risk up to the southern CWA border. Otherwise farther north, a more general area of rain with embedded thunderstorms is expected. Precip and northeast winds will likely limit highs at least a few degrees below current forecasts in the lower 50s. QPF around a half to 3/4" would aggravate/prolong minor flooding already in place for several river basis in the CWA. Another narrow ridge builds into the Midwest on Wednesday. Forecast soundings show better drying near the 900 mb level so this should be our better chance at seeing sunshine this week. If sun does manage to emerge, highs will approach the 60 degree mark. A cold front trailing an area of low pressure moving into the Great Lakes, moves into the area Wednesday night into Thursday. This results in chance pops for light rain. The front is expected to turn quasi-stationary in or just south of the CWA through Friday. Mid level flow begins to turn southwest during this time, resulting from more significant jet phasing and a longwave trof developing out west. This would lead to periods of showers and thunderstorms and the potential for heavy rain, though confidence on placement is low. A more significant shortwave and associated surface low is expected to emerge from the trof late in the week or during the weekend, but significant timing differences are noted, resulting in an extended period of pops. Southwest flow will favor above normal temperatures at least into the weekend. && .AVIATION...(For the 00Z TAFS through 00Z Monday evening) Issued at 628 PM CDT Sun Mar 22 2020 Precip has been steadily ending from the south and anticipate SPI/DEC/CMI should be done or very close to done as the 00Z TAFs go into effect this evening. Meanwhile, precip will linger later into the evening at BMI/PIA as another upper level disturbance moves across the region bringing more snow to that area. Soundings do show that temps for ice nuclei may be too warm/marginal at times which will cause precip to mix with or transition to rain and drizzle. Elsewhere, IFR ceilings are expected to persist overnight along with some fog and don't expect improvement until mid/late Monday morning when ceilings lift back to MVFR. Winds will become light and variable overnight. && .ILX WATCHES/WARNINGS/ADVISORIES... NONE. && $$ UPDATE...Deubelbeiss SYNOPSIS...25 SHORT TERM...25 LONG TERM...25 AVIATION...Deubelbeiss