Rain will be likely this weekend, especially during Friday and Saturday afternoon, when thunderstorms with heavy downpours are possible.
A stream of extreme amounts of moisture from the Gulf of Mexico and Atlantic Ocean will remain in place over the Finger Lakes for Friday and Saturday. By some measures, the amount of moisture in the atmosphere is near record levels for our region during this time of the year.
With all of that moisture in the atmosphere, plenty of heat, and a slow moving cold front, afternoon thunderstorms will be possible throughout the weekend. The best chance for thunderstorm development in the Finger Lakes will be on Saturday, but numerous storms are also expected Friday afternoon. By Sunday, the cold front will be pushing southeast of the region, keeping the thunderstorm threat lower.
Lightning and torrential downpours will be the primary threat with any storms. A few gusty winds may also be possible, especially on Saturday. Poor drainage areas, including urbanized locations, may be susceptible to some flash flooding, as will areas that see multiple heavy downpours.
Many areas will see substantial rainfall over the next few days, with a general one half to one inch falling. However, some areas may see much more rain, and a few will probably mostly miss out and see less than a quarter inch.
Hot and Humid
Along with the copious amounts of moisture in the atmosphere, temperatures will soar ahead of the front. While the increased chances for rain and clouds during the afternoon Friday and Saturday will keep the temperature a bit cooler than it was on Thursday, the difference will be hard to notice due to the drippingly high humidity.
Temperatures Friday will quickly rise from morning lows in the 70s to the low 80s by late morning. High temperatures should be reached during the early to mid afternoon, with highs ranging from the mid 80s to around 90 degrees. With dew points well into the 70s, the heat index will be about 10 degrees higher than the actual temperature, making it feel like 90 to 100 degrees across the region.
Saturday will be very similar to Friday. Temperatures overnight will remain above 70 degrees for most areas and should quickly shoot into the 80s during the morning hours. A few places may get to 90 degrees before the thunderstorms begin to develop during the afternoon. Heat index values will again soar well into the 90s.
Cooler, less humid air will start to work in behind the cold front on Sunday. While morning lows will be well into the 70s, afternoon highs should top out in the low to perhaps mid 80s. Dew points will retreat into the 60s. While still muggy, it will not be so unbearable and the heat index should remain in the 80s.
Finger Lakes Event Forecasts
Women Swimmin’, Ithaca, Sat. 8am
The annual Women Swimmin’ community swim for Hospicare will take place Saturday morning, starting at Cass Park and crossing Cayuga Lake. Temperatures will be around 75 degrees at the start of the swim with very high levels of humidity. While there is a very low chance for a shower, the morning hours are generally expected to remain dry. The lightning risk should be nearly zero at the time.