Area Forecast Discussion
Issued by NWS Cleveland, OH
Issued by NWS Cleveland, OH
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414 FXUS61 KCLE 231752 AFDCLE Area Forecast Discussion National Weather Service Cleveland OH 152 PM EDT Sun Jun 23 2024 .SYNOPSIS... A cold front will move east this afternoon before high pressure builds in for Monday and Tuesday. Another cold front associated with a low pressure over Ontario will move east across the area on Wednesday before high pressure returns for the end of the work week. && .NEAR TERM /THROUGH MONDAY/... 1:50 PM Update... Cold front draped across Northwest Ohio this afternoon has provided minimal clearing across northern Indiana and western Ohio this afternoon. A few showers are beginning to develop along the cold front this afternoon with hi-res guidance continuing to show continued shower and thunderstorm development along the front. There`s a decent axis of higher CAPE values out ahead of the front, but lingering cloud cover may inhibit the potential for any stronger or severe storms to develop over our western zones at least through the early part of this afternoon. 9:25 AM Update... Line of showers and thunderstorms that brought some isolated strong wind gusts earlier this morning is continuing to track east out of our local forecast area. First glance of 12Z data is continuing to indicate that there will be some redevelopment of showers and thunderstorms across the eastern half of the forecast area this afternoon and early evening. A fairly moist environment with dew points hovering around 70 degrees contributing to moderate instability with MUCAPE values between 1500-2000 J/kg and roughly 25-30 knots of 0-6 km bulk shear should support damaging wind gusts and isolated large hail. 630 AM Update... Decaying showers and thunderstorms continue to move east across the area this morning, producing wind gusts generally between 25-35 mph. Rainfall totals with this line all appears to be 0.25" or less as a result of the quick moving line. Behind this initial line of storms, conditions are clearing out although temperatures remain quite cool in the upper 60s to low 70s. The big question going into later this morning/afternoon is how well the atmosphere will be able to rebound ahead of the cold front which currently extends south across western Michigan into northwest Indiana. If the area can rebound enough to see marginal instability, the strong isentropic lift with the front could be enough to establish some additional storms along and east of I71. Confidence is pretty low at this point that the atmosphere will rebound enough to produce widespread severe weather, but will need to monitor the mesoscale environment over the next couple hours to really get a feel for the severe potential this afternoon. Stay tuned for updates to the forecast throughout today. Previous Discussion... Currently, a broad trough aloft is providing support for a surface low pressure to continue to move northeast through the western Great Lakes region. The area currently lingers in the warm sector of the low pressure with temperatures across the area in the 80s and dewpoints lingering in the mid to upper 60s. Looking upstream across northern Indiana, a line of convection continues to track east, gradually weakening in terms of intensity, but still maintaining widespread thunderstorms with gusty winds and lightning. A LLJ of 40- 45 knots has moved across the area resulting in non-convective gusty winds up to 20 knots this morning. This LLJ and mid-level support should be enough to maintain the line of convection, where locally higher gusts are possible. In the heaviest storms, expect very efficient rainfall of over 1"/hr as PWAT values climb over 2" and warm cloud layers deepen to over 13 kft. With this overall limited instability this morning, still expecting a general weakening trend with locally higher wind gusts and heavy rain possible. The trickier part of the forecast is for this afternoon as the aforementioned line of convection exits east of the area late morning. This afternoon, the cold front is expected to push east across the area, stirring up another potential round of scattered convection. Many ingredients, including a moist boundary layer, increasing instability to 1000-1500 J/kg, and a lingering LLJ will couple with strong isentropic ascent along the boundary to provide enough support for additional storms development along and east of I- 71. Primary concern with any storms that develop with be strong damaging winds, although with effective shear values of 20-30 knots isolated large hail cannot be ruled out. In addition to the severe potential, the PWAT values remaining over 2" and deep warm cloud layers will produce heavy rainfall. In areas that received precipitation with the initial round of storms, may see some flooding especially in urban and low lying areas. The biggest question mark with this forecast is in regards to how fast the atmosphere will be able to recover behind the initial round of convection. Widespread clouds are expected today which typically would limit instability and potentially limit convection, but given the strong surface lift and moisture rich environment confidence is low that the clouds will have as strong of an effect. To highlight these threats, SPC has issued a Slight Risk SWO for the far eastern counties and a Marginal Risk SWO for the remainder of the areas along and east of I-71. In addition, WPC has issued a Day 1 Marginal ERO for those far eastern counties. Showers and thunderstorms should primarily dissipate once the cold front pushes east late this evening. A few showers and storms may linger into late evening, but with a northwest flow becoming established across the area, colder 850mb temperatures near 10C will begin to push across Lake Erie and transition the lingering precipitation to primarily be lake enhanced with limited thunder potential. By mid-Monday morning all precipitation should end across the area as high pressure becomes established over the area. High temperatures today and Monday return to more seasonal, climbing into the low 80s for much of the area with the portions of the eastern counties possibly only reaching into the upper 70s. Overnight lows tonight will drop into the low 60s. && .SHORT TERM /MONDAY NIGHT THROUGH WEDNESDAY NIGHT/... A dry, stable pattern will allow for a pleasant night on Monday with temperatures falling below 60 degrees for a large portion of the forecast area - first time in about 2 weeks! Unfortunately, the remainder of the short term period will feature a more active pattern and return to warmer temperatures and high humidity. Surface high pressure will move east for Tuesday and return flow across the region will allow for temperatures to soar back into the upper 80s to lower 90s and dew points reach the 60s again. A minor shortwave will move through the region on Tuesday and allow for some small shower and storm chances, but the main show appears to be on Wednesday as better synoptic forcing will enter the region with a larger upper trough and surface cold front. Have PoPs increasing to likely and even categorical for Tuesday night into Wednesday. Have come concern about severe weather potential for Wednesday, as the present consensus for the timing of the main synoptic forcing features is Wednesday afternoon and evening, which coincides with peak heating of the day with upper 80s and near 70s dew points that would support a fairly robust thermodynamic environment for storms. This day will be one to watch moving forward. && .LONG TERM /THURSDAY THROUGH SATURDAY/... Thursday should be a repeat of Monday with high pressure entering behind the main synoptic system, allowing for a dry, stable environment with cooler than normal temperatures and pleasant conditions. The surface high will shift east on Friday as the ridge axis enters and return flow once again enters the region with highs achieving the mid to upper 80s again. A shortwave will override the ridge later on Friday into Saturday, followed by a stronger upper trough for the weekend. This will once again contribute to an active pattern with increasing storm potential for the weekend. && .AVIATION /18Z Sunday THROUGH Friday/... Stratiform rainfall from earlier this morning has left behind overcast MVFR conditions across most terminals. Showers are beginning to develop along a cold front draped across Northwest Ohio this afternoon. General timing for any impacts to terminals with these showers and storms will be between 18-22Z this afternoon. Wrap around moisture behind the cold front and parent low pressure will keep moisture over the region and 5000 ft BKN/OVC ceilings in place overnight tonight across terminals in Northeast Ohio and Northwest PA. High pressure builds overhead behind the cold front and will clear out any lingering cloud cover and returning terminals to VFR by Monday morning. Strong west winds 12-15 knots with gusts up to 25 knots, higher in thunderstorms, will continue this afternoon and evening across terminals. Winds turn more northwesterly behind the cold front by tonight while diminishing below 12 knots. Outlook...Non-VFR possible in scattered showers and thunderstorms across Northeast Ohio and Northwest Pennsylvania tonight into Monday. Additional non-VFR possible in showers and thunderstorms Tuesday evening through Wednesday. && .MARINE... After a rather benign marine weather week, the weather will be more active this week with several windows for marine headlines, several widespread storm chances, and generally increased winds across the lake. For today, southwest flow will increase ahead of a cold front this morning, winds will get close to 20 kt and will have a Small Craft Advisory for the winds starting this morning. The front and convection will cross the region later today and onshore flow will increase wave action, which will allow for a longer period for the Small Craft Advisory and these areas will be the land zones with the Beach Hazards Statement for increased swimming risk with the higher waves. Have tweaked the areas and timing of the marine hazards this morning just slightly to align with the current wind and wave forecasts. High pressure across the region on Monday will allow for decreasing northwest flow during the day, followed by light and variable flow overnight. Return flow on the back side of the high on Tuesday will allow for increasing south to southwest winds and there are some minor chances for showers and storms. A potent cold front will enter for Wednesday and bring widespread showers and storms to the region. Southwest flow will increase ahead of the front to at least 15 kt during the day on Wednesday. Winds will shift to the northwest behind the front on Wednesday night and will increase waves. This window could potentially need a Small Craft, but the forecast remains below at this time. High pressure will return to the region for Thursday and bring decreasing northerly flow. && .CLE WATCHES/WARNINGS/ADVISORIES... OH...Beach Hazards Statement through late tonight for OHZ010>012- 089. PA...Beach Hazards Statement through late tonight for PAZ001. NY...None. MARINE...Small Craft Advisory until 8 PM EDT this evening for LEZ142>144. Small Craft Advisory until 4 AM EDT Monday for LEZ145>149. && $$ SYNOPSIS...Campbell NEAR TERM...Campbell/Iverson SHORT TERM...Sefcovic LONG TERM...Sefcovic AVIATION...Iverson MARINE...Sefcovic