textproduct: Cleveland

WHAT HAS CHANGED

The forecast has trended rainier for tonight into the first half of Monday. There is potential for localized flooding during this time, best chance in the southern reaches of the CWA.

KEY MESSAGES

1) Additional rain is likely tonight into early Monday. Rain may be heavy at times and could lead to localized flooding, particularly in the southern part of the area.

2) A first taste of fall arrives this week with cooler temperatures periodic rain chances, especially on Wednesday.

DISCUSSION

KEY MESSAGE 1... After a brief break in showers his afternoon, another round of rain will move into the area this evening through tonight as a shortwave moves east along a slow-moving frontal boundary. By the time rain moves into the area, the boundary will likely be hugging the CWA border or be just to the south, which will make the rainfall forecast somewhat tricky. The heaviest rainfall will likely occur to the south/southwest of the local area, although there is potential that heavy rain clips the southern fringe of the CWA (mainly south of the US-30 corridor). Additional rain accumulation of around an inch (maybe locally higher amounts) is possible in southern zones if the frontal boundary ends up being a bit farther north than currently expected. If heavy rainfall materializes in the local area, there may be localized flooding in low-lying and poor drainage areas, especially in locations that see prolonged periods of moderate to heavy rainfall. Will need to keep an eye on radar and hi-res guidance trends and make adjustments to the forecast is needed. Opted to hold off on a Flood Watch due to low confidence in the placement of the heaviest rainfall and the greatest risk of flooding.

Rain chances will remain relatively higher through Monday morning with shower activity becoming more isolated Monday afternoon and evening.

KEY MESSAGE 2... By Tuesday, Canadian high pressure will shift into the region, allowing temperatures to decrease for the majority of the week. Highs will be in the 60s Monday through Friday with overnight lows in the 50s expected. Friday will likely be in the chilliest night of the week with forecast lows in the 40s at inland locations. While periodic and scattered showers are possible through Thursday, PoPs will peak on Wednesday as an upper trough pushes east across the Midwest. Dry weather will return by Friday and continue into next weekend.

It will be quite breezy on Monday and Tuesday due to a tight pressure gradient over the region as high pressure builds in from the north and low pressure passes across the Ohio Valley. Northeast wind gusts of around 30 mph are expected across NW OH with locally higher gusts to 35 mph possible along the lakeshore of NW OH.

AVIATION /18Z Sunday THROUGH Friday/

Low ceilings will be the main aviation challenge the rest of today into Monday, along with periods of light to moderate rain showers. Current cigs range from MVFR to IFR across the region, with some MVFR visibilities where rain is falling at KCLE, KCAK, and KYNG. Expect the steadiest rain to exit NE Ohio and NW PA by 22Z, with mainly just scattered showers, mist, and MVFR cigs late this afternoon and early evening. The next round of steadier rain will start to move into NW Ohio impacting KTOL and KFDY after 22Z with continued MVFR to IFR conditions, but expect this round to slide more to the south, so have steadier rain moving into KCLE, KMFD, KCAK, and KYNG later this evening into the overnight, with KERI staying drier. Visibilities will drop to at least MVFR in the steadiest rain in addition to the low cigs. Once this batch of rain departs, scattered showers and continued low cigs will continue Monday morning, especially along a KFDY to KYNG line.

N to NE winds will gradually increase to 5-10 knots this afternoon and evening, then further increase to 10-20 knots overnight. Gusts of 20-25 knots are expected late tonight and Monday morning, especially near Lake Erie.

Outlook...Non-VFR possible with showers and occasional thunderstorms through Thursday.

MARINE

Hazardous conditions are expected on Lake Erie through the first half of the week. Northeast winds will increase throughout this evening as a cold front pushes south of Lake Erie and Canadian high pressure begins to build in from the north. Small Craft Advisories and Beach Hazards Statements begin in the western basin at 00Z/8 PM with headlines spreading east across the lake overnight and into Monday morning. Expect winds to peak at around 25 knots Monday morning through late Tuesday night possibly through as late as Wednesday morning. Winds may periodically approach 30 knots, primarily in the open waters. Winds will slowly diminish Wednesday night into Thursday, although persistent easterly flow 15 to 20 knots may require an extension of headlines in the western nearshore zones into Thursday. East winds should diminish below 15 knots by late Thursday.

CLE WATCHES/WARNINGS/ADVISORIES

OH...Beach Hazards Statement from 8 PM EDT this evening through Wednesday evening for OHZ003-007-009>011. Beach Hazards Statement from 2 AM EDT Monday through Wednesday evening for OHZ012-089. PA...Beach Hazards Statement from Monday morning through Wednesday evening for PAZ001. MARINE...Small Craft Advisory from 8 PM this evening to 10 PM EDT Wednesday for LEZ142>146. Small Craft Advisory from 2 AM Monday to 10 PM EDT Wednesday for LEZ147-148. Small Craft Advisory from 8 AM Monday to 8 PM EDT Tuesday for LEZ149.