precipitation departure maps

We've been hearing it from folks in our viewing area, as well as others who are outside of the Susquehanna Valley. All who are asking the same questions, "Why are we getting so much rain," and "Why is there so much flooding right now?" The WGAL News 8 Storm Team has the answer.

String of storm systems

three main ingredients for torrential rain

Let's think back over the last several months. The Susquehanna Valley started off with bone dry drought conditions. A total of 7.52" of rain fell from January through April of this year. This past May, a total of 10.02" of rain fell! More than the first four months of the year combined! Needless to say, the good news is that rainfall managed to take us out of the almost year-long drought conditions in the area! Although, this situation has now become a double-edged sword.

how to best prepare for severe weather

Let's now look at the rainfall statistics from June. The average amount of rainfall we expect for June is 4.30". The amount we received was 5.24" of rain. For the month of July, the average amount of rainfall we expect to see is 4.68", and so far, July 2025 has received 5.11" of rain, so we are already above average for July in terms of how much rain we have gotten! All of this rain turns us from having a rainfall deficit, to now a rainfall surplus. Check out News 8 Storm Team Meteorologist Mike Susko's recent Facebook post on precipitation departures for Pennsylvania. An image of the post is below as well:

rainfall comparison

In short, we have an incredible surplus of rain across the entire Susquehanna Valley. Therefore, the ground won't be able to absorb any additional rainfall, which explains why we have seen so much flooding and how some communities have been flooding so easily.

Next, let's break down why we've been getting so many storms dumping incredible amounts of rain.

why so much rain?

Several ingredients are coming together at the same time for these flooding events to occur (see map below): We have had a string of storm systems & upper-level disturbances stream through from regions near the Pacific Northwest, the clockwise flow from the Bermuda High sitting stationary over the Atlantic Ocean helping to streamline warm & moist air from the Gulf, and a strong, slow-moving upper-level jet stream aiding in the vertical development of slow-moving thunderstorms. That is why we have seen so much rain.

Slow-moving storms

In conclusion, due to the Susquehanna Valley having a surplus of rainfall along with adequate upper-level patterns working hand-in-hand to create slow-moving thunderstorms, that is why we have seen so much rain & flooding in the last couple of weeks across the area. To best prepare for these situations & flooding events, be sure to stay tuned to the latest Storm Team forecast, turn on weather alerts, and if a flood warning or flash flood warning is issued for your area, heed the advice & take action!

~ The WGAL News 8 Storm Team

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