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Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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586 FXUS61 KCLE 281753 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 1253 PM EST Fri Feb 28 2025 .SYNOPSIS... Low pressure will drop across the Great Lakes through tonight, dragging a strong cold front through the area this evening. High pressure builds in on Saturday and persists through Monday. The next low pressure lifts into the Great Lakes Wednesday. && .NEAR TERM /THROUGH SATURDAY/... 1230 PM... Wind Advisory remains on track this afternoon with several sites beginning to observe southwest wind gusts around 45 to 50 mph towards the west across Indiana. Previous Discussion... A potent clipper on the leading edge of a tropospheric polar vortex lobe will drop southeast across the northern and eastern Great Lakes today and tonight. This clipper will push a strong cold front across the area this evening, with a brief return to much colder weather for this weekend behind it. It`ll be a mild Friday with increasingly gusty southwest winds ahead of the approaching cold front. We should stay dry through at least 4 or 5 PM area-wide. Lower stratus out east will exit this morning, with mid and high-level clouds quickly arriving from the northwest through the afternoon. Highs today will range from the low to mid 40s in Northwest PA, to the lower 50s along the I-77 corridor, to the mid to upper 50s in Northwest OH. Left the area of the Wind Advisory as is, as it best captures where confidence/duration in advisory-level gusts is greatest. There will be a 2-3 hour window starting around 4 PM where a few gusts to 45 MPH are possible near the eastern lakeshore, though the strongest low-level jet moves over that area after peak heating so mixing won`t be quite as optimal as in the advisory. A few gusts up to 50 MPH remain possible in the Wind Advisory area this afternoon or early evening. Pushed the start time of the advisory back until 12 PM, as am confident we won`t have any advisory-level gusts until at least that time. The end time of 7 PM looks good given loss of heating and low-level mixing with sunset this evening. Another push of 30-40 MPH gusts is likely late this evening into the overnight along and just behind the cold front, though expect those to remain sub-advisory. Some light rain showers are possible this evening along and just ahead of the cold front. Have at least a slight chance POP (20%) everywhere, with POPs increasing into the chance (30-50%) range east of the I-71 corridor and likely (60-70%) in Northwest PA. A secondary trough and stronger surge of cold advection drops through the area after midnight and into early Saturday morning, bringing potential for flurries and a few snow showers...with some enhancement south-southeast of Lake Erie. Temperatures aloft become cold enough for pure lake effect snow into the day on Saturday, with reasonably well-aligned northwest flow in the boundary layer over Lake Erie. That said, moisture depth quickly becomes shallow with lake-induced equilibrium heights only in the 5-7k foot range. The increasingly strong early March sun angle and icy lake are also negatives. Have slight to chance POPs (20-50%) for snow showers from North Central OH and the Mansfield area points east, though am not expecting particularly noteworthy accumulations. By early Saturday, temperatures are expected to fall well into the 20s. There will be little diurnal temperature rise on Saturday, with highs generally in the mid to upper 20s. Gusts up to 30 MPH will remain possible through about midday Saturday before slowly dropping off into Saturday night. Total snow accumulations through the day Saturday should generally be an inch or less... except locally up to a couple inches possible in the higher terrain of eastern Erie County PA. && .SHORT TERM /SATURDAY NIGHT THROUGH MONDAY NIGHT/... A brief shot of arctic air will continue for the remainder of the weekend as the axis of the mid/upper trough crosses the southern Great Lakes Saturday night into Sunday morning. This will bring the coldest air across the region, with 850 mb temps progged to reach - 15 to -18 C in the 06-15Z Sunday timeframe. This combined with NW cyclonic flow across Lake Erie and decent breaks in the ice cover will support lake-effect snow showers over the favored upslope areas of the primary and secondary snowbelts. A big limiting factor is that the airmass is very dry, but the boundary layer flow will remain decently well-aligned Saturday night into Sunday morning, and NAM BUFKIT forecast soundings suggest at least weak to moderate Omega (lift) into the DGZ as the trough axis swings overhead. For these reasons, slightly increased PoPs from the previous forecast since confidence is building for the snow showers. Most areas in the primary and secondary snowbelts inland from the lake will see a few tenths to up to 1 inch of snow, but could see an additional 1 to 2 inches in NW PA where HREF and RGEM guidance is suggesting a possible Lake Huron connection. The lake-effect snow showers will shut down quickly Sunday afternoon as the mid/upper trough axis starts to push into the eastern Great Lakes and a large area of surface ridging builds northeastward from the Mississippi Valley. Most areas will see sunshine by late afternoon. As the high slides across the region Sunday night, clear skies and light winds will set up strong radiational cooling resulting in a very cold late winter night. The cold airmass will quickly retreat Monday as the mid/upper trough lifts out of the Great Lakes allowing for rapid height rises across the region. As the surface high slides into the Mid Atlantic, it will set up southerly return flow. This will signal a warming trend that will last into midweek. A mid-level shortwave cresting the building mid/upper ridge late Monday and Monday night will encourage isentropic ascent along a warm front as it lifts northward, and this will lead to a few showers by Monday night along with skies becoming overcast. Highs will range from the low to mid 20s in NE Ohio and NW PA to the low to mid 30s in north central and NW Ohio Sunday, warming into the upper 30s to mid 40s Monday. Lows Saturday night will range from the low to mid teens, with low teens to low 20s Sunday night. A few single digits are likely in NW PA Sunday night. Lows Monday night will be much milder in the low to mid 30s, with some mid to upper 20s holding on in NW PA. && .LONG TERM /TUESDAY THROUGH THURSDAY/... A very active and mild midweek period is expected as a deep mid/upper trough looks to progress from the Rockies through the Plains and Mississippi Valley Tuesday through Wednesday while phasing with a northern stream mid/upper trough dropping through the Great Lakes. This will result in a very dynamic storm system, with a rapidly deepening surface low likely developing over the southern Plains Tuesday and tracking into the central Great Lakes by Wednesday night. Deterministic and ensemble guidance are showing impressive agreement on the timing and overall track of this storm system for 5 days out, with the typical uncertainties regarding the exact timing and track. This is a favorable overall setup and track for a surge of warm air, high winds, and possible strong to severe thunderstorms ahead of the trailing powerful cold front. This will be monitored in the coming days. Much colder air will spread into the region behind the storm system Wednesday night and Thursday, with rain showers changing to snow showers along with the possibility of lake-effect snow showers. Stayed with NBM temperatures at this point, which are probably conservative based on the pattern. This yields highs in the mid 40s to low 50s Tuesday and mid 50s to near 60 Wednesday before falling into the low to upper 30s by Thursday. && .AVIATION /18Z Friday THROUGH Wednesday/... VFR across the TAF sites early this afternoon with primarily VFR to persist into tonight. Main concern for the TAF period this afternoon will be gusty southwest winds of 20 to 25 knots with gusts of 35 to 40 knots. The highest confidence in 40-knot wind gusts is generally along and west of the I-71 corridor (CLE/MFD/FDY/TOL). Winds will shift towards the west and northwest behind a strong cold front later this evening and overnight. Winds will remain elevated, 15 to 25 knots with gusts of 30 to 35 knots. A brief period of LLWS is possible between the strong southwesterly wind gusts this afternoon and the elevated west to northwest winds behind the cold front late this evening. Otherwise, some snow showers are possible along and behind the cold front late tonight into early Saturday morning, particularly across the eastern TAF sites. Have introduced tempo groups, briefly dropping vsbys down to IFR, though confidence remains low on coverage. MVFR ceilings may linger behind the cold front Saturday morning, particularly across the eastern TAF sites. Outlook...Non-VFR possible in lake effect snow showers and/or lake effect clouds late Saturday into Sunday. Non-VFR expected to return in widespread rain late Tuesday through Wednesday. && .MARINE... Lake Erie continues to be primarily ice covered and thus, the issuance of Small Craft Advisories remains suspended. Strong SW winds of 15-25 knots with gusts of 25-35 knots will develop on the lake late this morning through the afternoon. This could result in dangerous ice floes as any ice attached to the south shore or the islands breaks off and drifts northeastward. A Marine Weather Statement has been issued for this potential. Otherwise, winds will turn to the NW behind a cold front tonight with speeds still in the 15-25 knot range before decreasing to 10-15 knots Saturday afternoon and evening. NW winds will further decrease to 5- 10 knots Saturday night and Sunday while backing to SW by late Sunday. SW winds of 5-10 knots will continue through Monday before turning S and increasing to 10-20 knots by Tuesday. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Wind Advisory until 7 PM EST this evening for OHZ003-006>011- 017>020-027>030-036-037-047. PA...None. MARINE...None. && $$ SYNOPSIS...Sullivan NEAR TERM...Kahn/Sullivan SHORT TERM...Garuckas LONG TERM...Garuckas AVIATION...Kahn MARINE...Garuckas