Marine Weather and Tide Forecast for Irondequoit, NY

NEAR TERM /THROUGH TONIGHT/
Latest satellite and radar shows storms quickly developing along a lake breeze boundary east of Lake Erie early this afternoon.
Additional storms have been developing across southwest Ontario that will continue to move east towards Niagara Co over the next few hours. Per the latest CAMs, showers and thunderstorms will continue this afternoon across western NY with the prefrontal environment as well as with another round potentially overnight with the cold frontal passage. Latest SPC mesoanalysis has 1000-1500 J/kg of MLCAPE with up to 30 kt of effective shear more conducive of multicellular convection with heavy rainfall (more details below)
and strong downburst winds as the main hazards. SPC's Marginal Risk for Severe Thunderstorms that clips Chautauqua Co is more focused on the remnants of convection over the Midwest with a progressive shortwave. Plenty of uncertainty surrounding upstream development with considerable spread highlighted in the CAMs, but any remaining storms with the convective complex will likely not arrive across western NY until after 11 PM Wednesday.

Heavy Rainfall: Latest NAEFS and EC guidance shows abnormally high PW values across western NY this afternoon. and forecast soundings continue to suggest moist profiles through the column with skinny CAPE and warm cloud layer depth >10kft. Additionally, experimental guidance has suggested that precipitation accumulations with afternoon thunderstorms could exceed flash flood guidance, specifically around the Finger Lakes region headed into this evening. One limiting factor will be that storm motions will be close to 20 kt reducing residence time over specific areas, however initial storm motions have be parallel to the lake breeze boundary off of Lake Erie with training storms. Will need to continue to monitor storm development through this afternoon and evening for any potential flash flooding hazards as MRMS QPE with initial storms have shown the capability of 1.5+ inch per hour rates.

SHORT TERM /THURSDAY THROUGH FRIDAY/
Gusty winds are expected across the Niagara Frontier Thursday morning with a 998mb surface low to our northwest traversing across southern Ontario. 850mb winds will be above the climatological 99th percentile for mid-June, around 45 kt. Low-level CAA behind the front will support vertical momentum transport enabling winds gusting 40-50 mph. Latest NBM has been slowly trending upward with probability of wind gusts exceeding 41 kt still low (15-25%).
Decided to hold off on any headlines for portions of the Niagara Frontier east towards Rochester, but upcoming shifts will continue to monitor the potential need for an advisory.

With the cold front still moving through the area, showers and thunderstorms look to develop midday across the Southern Tier through the Finger Lakes region where MLCAPE will be marginal (~500 J/kg), but forcing will be enough to support development. Shear and instability profiles will be better for development of organized convection farther east, especially in north-central NY east of Lake Ontario. Strong downburst winds and heavy rainfall will be the main hazards once again. By late Thursday afternoon into the evening, the 500mb trough axis will be passing overhead with any storms associated from the surface cold front well off to the east of the CWA, but a few lingering showers may persist.

As height rises begin across the central CONUS, a few shortwave disturbances still appear to pass in the flow before temperatures warm up across western NY late in the weekend. The first of these disturbances will pass Friday afternoon into the evening with showers developing under northwest flow aloft.

LONG TERM /FRIDAY NIGHT THROUGH TUESDAY/

Dangerous Heat Sunday Through Tuesday

A strong ridge will build into the eastern half of the CONUS during the period. This will lead to increasing heat and humidity through the weekend and into the first half of next week. While the ridge and associated sfc high will provide dry weather for a large chunk of the period, there will be the potential for showers and thunderstorms early on in the period from Saturday afternoon into the first part of Sunday morning. A ridge-runner complex of thunderstorms within a northwest flow will cross a portion of the area during this time. Confidence in the exact track/location is low still among guidance with a variety of solutions still, but the main focus is from Rochester and points east, including far enough north to miss most of the North Country as well.

500 hPa heights building to around 596dm will support hot and humid conditions. Afternoon high temperatures will reach the mid 80s to mid 90s for Sunday through Tuesday. Some upper 90s will be possible for the warmer interior lower elevations on Monday and Tuesday. Heat index values in the mid 90s to around 100 degrees will also be possible for Sunday through Tuesday in some locations.

Shower potential will increase for late Tuesday into Wednesday as the next system approaches from the northwest, but guidance is still uncertain on this potential. Wednesday also looks a bit cooler, but above normal. Temperatures for Wednesday are also still uncertain somewhat as well and dependent on the potential for a cold front to move through the region.

AVIATION /17Z WEDNESDAY THROUGH SUNDAY/
MVFR ceilings this morning have lingered around KBUF and KIAG, but satellite imagery as of this morning has shown thinning of low-level clouds. Showers and thunderstorms have been developing across western NY early this afternoon and will continue into the evening.
Thunderstorms moving overhead any terminals will result in significant reductions in visibility due to heavy rainfall along with gusty winds. These storms will continue to move east from the Lake Erie shoreline with another round of overnight showers and thunderstorms likely, especially for KBUF, KIAG, KJHW, and surrounding terminals after 03z. Gusty southwest winds up to 40 kt are expected Thursday morning through the early afternoon from the Niagara Frontier east towards KROC.

Outlook...

Thursday Night...VFR/MVFR with showers and thunderstorms likely.
Breezy morning synoptic winds.

Friday...Mainly VFR. A chance of showers and thunderstorms, mainly east of KROC.

Saturday...Mainly VFR. Increasing chances for showers and thunderstorms.

Sunday and Monday...Mainly VFR.

MARINE
A cold front will stall to our west today, with a southwest push of wind across the Lower Great Lakes that generally will remain 10 knots or less through the day as lake breeze circulations become established with the inland warming. A light chop will be found on the northeast portions of the Lakes.

Tonight a wave of deepening surface low pressure on this stalled front, advancing from the Ohio Valley to northwest of the Lower Great Lakes will bring an increase in the southwest winds late tonight and into Thursday morning. Sustained southwest winds well over 15 knots will bring likely small craft advisories to the Lower Great Lakes Thursday.

These winds will veer to westerly and then northwesterly tomorrow night behind the cold front, with ample speed to support waves of 4 feet or great on Lake Ontario deep into Thursday night.

BUF WATCHES/WARNINGS/ADVISORIES
NY...None.
MARINE...None.