Great debate on the weekend weather here in WNY. Woes or wins is a perfect description for all the possible outcomes!
On Monday we were well on our way to the 80s for Sunday and less than 24 hours later the warm front is retreating, as a cold front marches cooler and wet weather right into WNY.
Saturday, between the European model and the GFS model we still have some "wobbling" between runs which means the placement on the warm front still is not set. This means, if we do have it riding to the north of WNY, we stay drier through the day and warmer. Current models bring rain in the morning on Saturday, drys out for a time in the afternoon and starts to move south in the evening. This would give Saturday a wet feel but it would still allow temperatures to rise into the 70s.
This trend also means Sunday is going to be wet to start but with moderating temperatures in the afternoon. The faster the front moves, the quicker we end rain on Sunday and end with seasonable temperatures in the 60s.
From everything I've been looking at, Saturday looks to be the warmer and more summer-like day with showers and scattered thunderstorms. We say in the business - "never trust a warm front", they tend to be wishy washy in a way, they get pushed around by cold air and a cold front usually is stronger than a warm front, meaning - warm air loses.
Taking a look at temperature advection (the change of temperature of air caused by the wind moving it) several models, including the GEM, GFS and EURO all show warm air advection on Saturday and cold air advection on Sunday. This would indicate Sunday going cooler as well without any 80s for WNY!
So this is what goes into looking ahead to the weekend at the start of the work-week. Of course as new data disperses and models (hopefully) come into better agreement our confidence in the forecast grows!