Warmer temperatures, significant rainfall and melting snow and ice will combine to threaten communities affected by ice jam on rising creeks and streams starting today, the National Weather Service reported.
Warm, moist air passing over the remaining snowpack will also create substantial fog with visibility at or below one-quarter mile in places.
A dense fog advisory is posted for the southern half of Western New York through 4 p.m. today.
The weather service also issued a flood watch for all of Western New York through Tuesday evening.
The weather service calls for rain today and temperatures nearly 15 degrees warmer than normal — in the mid 40s. Up to a quarter inch of rainfall is possible.
Tonight, more rain is expected with up to a half inch possible. Temperatures won't drop much. They'll remain in the low 40s overnight.
More showers are likely Tuesday, weather service forecasters said. The high is forecast to be back into the mid 40s with up to another quarter inch of rain possible, the weather service said.
"Area creeks and rivers still have ice in place," the weather service said. "Rises in water level can break up this ice, which can then become jammed there were are constrictions in the river or creek channel, such as curves or other restrictions."
It added: "Localized flooding will be possible in the vicinity of any ice jams. People living in areas that are prone to ice jam flooding should take the time in advance to prepare for the potential for flooding."
It would be the second time in less than two weeks that ice jams resulted in flood waters rising in the region.
There could be mitigating factors to flooding this time around though.
"A less impressive snowpack, lower temperatures and less rainfall compared to last week's flooding should translate into more localized flooding," the weather service said. "Flooding should not be as widespread as the last event."
Still, forecasters advised residents in flood prone areas to be aware of the potential for rising waters over the next day or two.
Chillier temperatures, and more snow, is forecast late Tuesday into Wednesday as winter returns for the middle of the week.
Another warm-up, with rain, is expected by the weekend, forecasts show.