UPDATE, 8:30 p.m.: The National Weather Service has issued a flood warning that includes northeastern Livingston County.
The warning, in effect until 11:15 p.m., also includes southern Monroe, Ontario and southwestern Wayne counties.
At 8:07 p.m., Weather Service Doppler radar indicated heavy rain due to thunderstorms. Flooding is ongoing or expected to begin shortly in
the warned area. Between 1 and 2 inches of rain have fallen.
Some locations that will experience flooding include Canandaigua, Geneseo, Avon, Mount Morris, Victor, Honeoye Falls, Conesus, Bristol, Caledonia, Lima, Clifton Springs, Scottsville, Bloomfield, Honeoye, Hemlock, Farmington, Mendon, Gorham, East Bloomfield and Rush.
Additional rainfall amounts up to 1 inch are possible in the warned area, the Weather Service said.
UPDATE, 8 p.m.: As thunderstorms continue across the region, the National Weather Service has issued a severe thunderstorm warning for northeastern Livingston County, southeastern Monroe County, Ontario County and southern Wayne County until 8: 45 p.m.
At 7:37 p.m., a severe thunderstorm was located over Honeoye Falls, or 11 miles south of Brighton, moving east at 15 mph.
Weather Service radar indicated 60 mph wind gusts with the storm.
Locations impacted include Lima, Geneva, Canandaigua, Newark, Lyons, Palmyra, Victor, Honeoye Falls, Bristol, and Clifton Springs.
This includes the following highways Interstate 390 near exit 11, Interstate 90 between exits 46 and 42.
UPDATE, 4:30 p.m.: The National Weather Service has issued a severe thunderstorm warning that includes southwestern Orleans and northwestern Genesee County.
The warning is in effect until 5:30 p.m., and also includes northeastern Erie and Niagara counties.
At 4:23 p.m., a severe thunderstorm was located near Lockport, moving east at 15 mph.
Weather Service radar indicates 60 mph wind gusts and quarter-size hail, the Weather Service said.
Minor damage to vehicles is possible. Expect wind damage to roofs, siding and tress, according to the Weather Service.
A severe thunderstorm watch has been issued until 11 tonight by the National Weather Service for more than three dozen upstate New York counties, including each of the four GLOW region counties.
Genesee, Livingston, Orleans and Wyoming counties are included in the watch, which was issued by the Weather Service’s Storm Prediction Center in Norman, Okla.
The watch also includes Albany, Cayuga, Chenango, Clinton, Cortland, Erie, Essex, Franklin, Fulton, Hamilton, Herkimer, Jefferson, Lewis, Madison, Monroe, Montgomery, Niagara, Oneida, Onondaga, Ontario, Oswego, Otsego, Rensselaer, Saratoga, Schenectady, Schoharie, Schuyler, Seneca, St. Lawrence, Tompkins, Warren, Washington, Wayne and Yates counties.
Strong to severe thunderstorms are possible late this afternoon and early evening, with a line of showers and storms expanded to cross the counties lining th south shore of Lake Ontario after 5 p.m.
Strong to severe thunderstorms are possible late this afternoon and early evening in the four-county GLOW region, according to the National Weather Service.
Main hazards are damaging wind gusts and marginally severe hail. There is also marginal risk for locally heavy rainfall and flooding, the Weather Service said.
While no watches or warnings have yet been issued, the Weather Service did issue hazardous weather outlook and special weather statements for Genesee, Livingston, Orleans, Wyoming and Niagara, Monroe, northern and southern Erie, Ontario, Wayne, northern Cayuga, Oswego, Jefferson and Lewis counties in western and central New York. The special weather statement also included Chautauqua, Cattaraugus and Allegany counties.
A cold front poised over southern Ontario during the midday will push south this afternoon and evening. Since the bulk of today will feature plenty of sunshine over the region, the airmass will become quite unstable and thus favorable for strong to severe thunderstorms to develop along and ahead of the front, the Weather Service said.
The strongest thunderstorm activity will likely impact the Thousand Islands region after 3 p.m., then as the broken line of showers and storms push south, they will cross the counties lining the south shore of Lake Ontario after 5 p.m. The activity is then forecast to weaken somewhat as it makes its way further south into the Southern Tier by nightfall, the Weather Service said.
The greatest threat with the expected convection will be damaging straight line winds and possibly some hail, according to the Weather Service.
Given the recent significant rains, the wet antecedent conditions will enhance the risk for localized flooding from downpours with the thunderstorm activity. This risk may be minimized by the steady, progressive nature of the storms, the Weather Service said.