910 FXUS61 KCLE 191646 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 1246 PM EDT Tue Mar 19 2019 .SYNOPSIS... High pressure over the Ohio Valley today will drift east to off the Mid-Atlantic coast by Wednesday. Low pressure over eastern Ontario will lift a warm front across the area on Wednesday afternoon, followed by a cold front on Thursday. High pressure over the Central Plains on Friday will build east over the region for the weekend. && .NEAR TERM /THROUGH WEDNESDAY/... Update...No changes for the afternoon update. Previous Discussion... High pressure over the Ohio Valley today will keep the area dry, as an upper trough departs the region. Some scattered cloud cover may develop later this afternoon as there is some weak warm air advection in the low levels, but the air mass over the region is fairly dry, so would only expect some cumulus at best. With the loss of diurnal heating, any clouds will diminish overnight and keep the area mostly clear. Temperatures for today will perform a bit better than Monday with mid 40s expected with sunshine in the area. An upper trough will swing through the Great Lakes region on Wednesday, supporting a low pressure system over eastern Ontario. A warm front will move through the forecast area ahead of this low on Wednesday afternoon, bringing increased southerly flow and cloudiness to the region. Believe that it will be tough to get precipitation with the warm frontal passage given the lack of low level moisture, but moisture will improve as the forecast area gets into the warm sector of this system. The best chance for rain will be with the upper trough later in the day on Wednesday. With this, have trimmed back PoPs across the area with chance PoPs into Toledo around Noon, slowing expanding eastward through the afternoon. The trough axis approaches the western CWA by 00z, so have likely PoPs for the west half in the very late afternoon hours. Temperatures on Wednesday will be warmer and even above normal into the lower 50s. && .SHORT TERM /WEDNESDAY NIGHT THROUGH FRIDAY NIGHT/... Digging upper level trough will move east southeast across the Great Lakes region Wednesday night into Thursday with an attendant cold front pushing east across the area. Have opted for high likely/low cat pops with precip ongoing at the start of the period. The front will push out of the area during the day Thursday, with drier conditions working into the area as ridging builds into the region. There may be some lingering precip associated with lake effect and lingering frontal forcing east Thursday afternoon, but dry conditions are expected by Thursday evening. Marginal surface/boundary layer temps suggest a mix of rain and snow for most of the area Wednesday night, with precip becoming predominantly rain during the daytime hours Thursday. A secondary cold front will cross the Great Lakes and push across the area late Thursday night through early Friday. Have generally chance pops for the eastern half o the area after 06Z Friday, with mainly snow expected given model temperature profiles. Ridging will build east across the area Friday night ending any threat of precipitation. Lows Wednesday night will be in the mid/upper 30s. Highs Thursday and Friday will be in the low to upper 40s, with temps a touch cooler on Friday across the northeast part of the forecast area. Lows Thursday night will be in the upper 20s to low 30s, with lows Friday night dropping into 20s. && .LONG TERM /SATURDAY THROUGH MONDAY/... Long term period starts out quiet across the area, with a large area of high pressure building east across the region Saturday through Sunday. Model details become a bit uncertain by Sunday night into Monday, but it appears a more active period is in store with the mid/upper level pattern flattening out across the CONUS and low pressure moving east from the Plains into the Ohio/Tennessee valleys as another upper trough sinks south through the Great Lakes. This would bring some precip potential to the area by Sunday night through Monday, but for now will opt for slight chance/low chance pops for the period given the model differences at this time. After a cooler day on Saturday with highs in the low to upper 40s, temps will be warmer for Sunday and Monday will highs in the 50s. && .AVIATION /12Z Tuesday THROUGH Saturday/... High pressure across the region this afternoon allowing for light winds and a healthy crop of diurnal cumulus. Soundings show sufficient dry air above and below the cu layer for mixing/entrainment preventing shower development and should allow for a rapid late afternoon dissipation. Also, the lack of cu along the immediate shoreline east of KCLE showing a lake breeze. Expect VFR conditions to persist through the evening and overnight. Could see patchy morning haze around dawn but for now will leave out. Wednesday models bring precip in from the west. Expect VFR CIGS to develop and lower late tonight west spreading east through late morning and early afternoon. OUTLOOK...Non-VFR conditions possible in light rain beginning Wednesday afternoon west spreading east and continuing into Thursday. NON-VFR possible again Friday. && .MARINE... Quiet stretch of weather continues across the lake with high pressure slowly moving east through the region today through Wednesday. A cold front will cross the lake Wednesday night into Thursday, with southerly winds becoming westerly. Another strong cold front will push southeast across the lake Thursday night into Friday, with winds becoming more north/northwest and increasing to 15-25 kts. High pressure will regain control across the area Friday night through Sunday with winds fairly light across the lake. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...None. PA...None. MARINE...None. && $$ SYNOPSIS...Sefcovic NEAR TERM...TK/Sefcovic SHORT TERM...Greenawalt LONG TERM...Greenawalt AVIATION...TK/Sefcovic MARINE...Greenawalt