textproduct: Cleveland

SYNOPSIS

High pressure builds across the region today through Saturday night. A low pressure system will deepen over the mid-Mississippi Valley and move east dragging a strong cold front through the region early on Monday. Troughing will linger behind the front over eastern Lake Erie.

NEAR TERM /THROUGH SUNDAY/

High pressure will briefly build into the region today as and upper level ridge builds over the central CONUS. These features will progress eastward through Sunday morning with quiet weather expected. Today's temperatures will warm up into the mid to upper 30s with some areas hitting 40 with mostly cloudy skies to accompany the warmer temperatures. Early Sunday the ridge will build off towards the east coast as an upper level trough deepens over the north central Great Plains. At the surface, a low pressure system will begin to take shape in the mid-Mississippi Valley and move northeastward into the Great Lakes region. A warm front will move north through the region during the afternoon on Sunday bringing with it widespread rain and much warmer temperatures. Refer to the short term section for impacts with this system as the majority of them will occur Sunday night through Monday. Highs on Sunday will be well into the 50s with even some low 60s making an appearance.

SHORT TERM /SUNDAY NIGHT THROUGH TUESDAY NIGHT/

Sunday night the low pressure system will deepen rapidly down to near 975mb by Monday morning as it enters the Great Lakes region. There will be plenty of impacts to talk about with this system as it moves through.

To start, the precipitation should be ongoing across northern Ohio into Pennsylvania with the warm frontal passage and ahead of the cold front. Some models, mainly the Canadian, have been showing increased total QPF across those locations of well over 2 inches through Monday afternoon. Most of the other models have been around 1-1.5 inches of total QPF. NBM probabilities of precipitation over 1.5 inches have dropped over the past couple of runs, though are still sitting around 40-50% for the areas near the lake shore from Cleveland up through Erie, PA. A feature working in favor of lower QPF for this system will be a couple of things. Firstly, after the warm front passes through, the majority of the precipitation looks to stay north over Lake Erie. Can't rule out it lingering a touch further south around the lake shore, hence the probabilities mentioned above, but the trends have shown the northern progression. Additionally, the cold front should pass through fairly quickly Monday morning and the large bulk of precipitation falling as rain should taper off. With all of that said, WPC has the entirety of the lake shore within a marginal ERO and will need to monitor this as it develops.

The second impact with this system will be the strong wind potential. Winds across the region will be on the rise Monday morning as the low rapidly deepens and the pressure gradient strengthens with low level winds around 50-60 knots at and around 5k feet. Mixing levels will be just below that level though and could mix gusts of 40-45mph down to the surface. Currently, probabilities of gusts in excess of 45mph are around 30-50% for western Ohio and along the lake shore and 20-30% for gusts over 50mph. Potential for a Wind Advisory for those locations is increasing and will most likely be needed. Winds will stay elevated, but below advisory criteria through Tuesday before tapering off Tuesday evening.

Lastly for impacts with the cold front, there is a low chance for severe weather, in the form of strong to damaging wind gusts across the region. Models have shown a fairly thin QLCS feature forming along the cold front which will move through the region early Monday morning. There will be a minor instability with the warming from the passing warm front earlier on Sunday that will generate MUCAPE around 100-300 J/kg. As mentioned, the main concern will be the rain showers mixing down severe level gusts, though confidence is low given the minor instability and is also noted in the SPC Day 2 severe weather outlook with much of the region being located in a marginal risk.

Behind the cold front, temperatures will begin to plummet as 850mb temperatures of -14C to -16C move in to the region. The high for Monday should be around or just after midnight around the mid to upper 50s and fall to the mid 20s by the evening. Additionally with the influx of cold air, the rain will being to change over to snow throughout the morning and be all snow by the afternoon. Outside of the snowbelts will have accumulation around an inch, though could be higher in some spots as a connection to Lake Michigan may form and impact some western counties. Within the snowbelt, consistent lake effect snow is expected through the remainder of the short term and into the long term periods. At this time, there is increasing confidence in headline level snow accumulation across the snowbelts with higher totals possible in northwestern Pennsylvania as north to northwesterly flow will allow for a connection to Lake Huron.

Morning low temperatures to start Tuesday will be down in the high teens to low 20s across the region with highs during the day being not much warmer in the mid to upper 20s.

LONG TERM /WEDNESDAY THROUGH FRIDAY/

Lake effect snow showers across the snowbelts are expected to continue through much of the long term as a trough develops over eastern Lake Erie. There will be periods of off an on lake effect, though a weak low pressure system is expected around mid-week that will reinforce the lake effect machine. In additions, this system could bring widespread light snow accumulation to the region, so will need to monitor it for changes. Temperatures will also stay cold due to the large upper level trough over eastern Canada. Highs will struggle to reach the 30s through the end of the week and overnight lows will be down in the teens.

AVIATION /06Z Saturday THROUGH Wednesday/

Low cigs and occasional low visibilities in mist will be the theme overnight into this morning, with very slow improvement through the day today. The low-level environment has dried out a bit more than anticipated, so pulled back on the mist and fog early this morning, but widespread IFR and occasional LIFR cigs will continue. KMFD, KCAK, and KYNG have the best chance to see LIFR cigs and visibilities early this morning, but confidence is higher in just IFR conditions areawide. Drier air will finally improve most terminals to MVFR this afternoon, but IFR will likely redevelop tonight.

NW winds will decrease to 5-10 knots early this morning while becoming NE, and NE winds of 5-10 knots will continue through the day today. Winds will become SE at 5-10 knots tonight.

Outlook...Non-VFR ceilings will continue tonight. A low pressure system will target the region on Sunday and Monday. Non-VFR will be expected with rain and potentially some embedded thunder on Sunday. Rain transitions to snow with a strong cold front on Monday. Westerly wind gusts of 30 to 40 knots are possible with and behind the front on Monday. Non-VFR expected in snow showers and low ceilings for NE OH and NW PA for Monday night through Wednesday.

MARINE

A brief ridge of high pressure across the eastern Great Lakes will exit to the east today. Northerly winds 10-15 knots this morning and afternoon will eventually ease to 10 knots or less while turning easterly this evening. By Sunday, southeasterly winds 10-15 knots in the morning will increase to 15-20 knots and turn southerly by Sunday afternoon ahead of a deepening low pressure system. The low will glide from the Central Plains into the Great Lakes bringing a period of strong southwesterly to westerly winds to the region beginning Sunday night/Monday morning. The low will drag a cold front east across the lake as it deepens early Monday. Westerly winds increase substantially to 35-40+ knots during the day on Monday in the cold air advection regime. Have hoisted a Gale Watch east of The Islands early Monday morning through Tuesday evening. There remains a non-zero chance for storm force winds on Lake Erie given the dynamics of this low pressure system. Will continue to monitor trends in the forecast over the next few cycles. The strong southwesterly winds will also pose a threat for low water in the western basin of Lake Erie.

Northwesterly winds 30-35+ knots on Tuesday behind the passing low. Winds will gradually return westerly through the day Tuesday but will remain elevated at 20-30 knots through the forecast period as a trough lingers across the Great Lakes region.

CLE WATCHES/WARNINGS/ADVISORIES

OH...None. PA...None. MARINE...Gale Watch from late Sunday night through Tuesday evening for LEZ144>149-164>169.