A significant, beneficial rain event will unfold across the Finger Lakes between Thursday and Saturday.
Rain Storm Set Up
As far as big weather events go, the set up for this rain storm is fairly uncomplicated, at least at its onset.
Tuesday night, a cold front pushed south through the Finger Lakes. After spending the day over Pennsylvania on Wednesday, this front will start to work back north Wednesday night. Areas of low pressure will move along the front, bringing rain into the Finger Lakes.
There will be two main periods of rain. The first will be Thursday morning as the front pushes through. Some of the rain may start before the sun rises, but most of the region will see rain during the daylight hours Thursday morning.
The eastern Finger Lakes will dry out Thursday afternoon, but showers will linger further west as low pressure moves over the area. This low will slow down and become absorbed by the front, spreading rain back across the Finger Lakes by Thursday night.
A new area of low pressure will develop off the New England coast, turning this system into a full fledged nor’easter. The set up gets a bit more complex at this point, as it typically the case when lows jump to the coast. Added into the mix will be the possibility of some tropical development off the southeast coast. Should a tropical storm develop, it would be given the name Otto.
Regardless of development, this tropical low will get absorbed by the nor’easter this weekend, and could help prolong the rain on Saturday across the Finger Lakes.
What to Expect
For a drought stricken area, the prospect of getting 4 inches of rain over a two or three day period is surely tantalizing and has started to stir up a bit of a buzz across the Finger Lakes. Most areas will probably not see that much rain, but a few very well may end up close to 4 inches by Saturday, especially if the rain lingers on Saturday.
More generally though, amounts of 2 to 3 inches are likely across much of the Finger Lakes. Some areas will probably fail to reach the 2 inch mark, just as some may exceed 4 inches.
There is some disagreement among the major computer models where the corridor of heaviest rain will fall. The European model tends to be further west, towards western New York, while the American GFS model focuses on the eastern Finger Lakes and Central New York. Both models show the heaviest rain to be early Friday.
Given the drought and the long duration of this event, flooding is not expected to be a major issue. Poor drainage areas and urban centers could see some localized areas of mostly minor flooding. The poor drainage problems could be enhanced by fallen leaves clogging drains, so make sure to occasionally unclog your drains.
Wind does not appear to be a major factor with this storm over our area. Top wind gusts may approach 30 mph towards the weekend as the nor’easter really cranks up, but winds will otherwise be modest.
There is some question on the possibility of snow on the back side of this system Friday night and with any lingering precipitation Saturday night. For most of the Finger Lakes, any snow would be limited to a few flakes mixing in with the rain with no accumulations.
The higher elevations across the Southern Tier and Central New York have a very small, outside chance of seeing a coating of snow, especially if the system lingers late into Saturday. I would estimate the chances of this happening at less than 10%.
The best chance for accumulating snow this weekend will be across the Adirondacks. Some of the high peaks could turn white before the weekend is done, possibly with several inches falling. The chances for at least an inch of snow over some parts of the Adirondacks is probably greater than 50% at this point.