Nelson Vaz, meteorologist at the National Weather Service in New York, has put Ridgefield under an active flood watch for Tuesday afternoon.

The Danbury area is projected to receive between one-and-a-half inches and one and three-fourths inches of rain Tuesday afternoon and into Tuesday night.

"There is high confidence in showers and thunderstorms moving through much of the region this afternoon through this evening, but predictability is low on exactly where and how long this activity will occur over a given area," said Vaz around 6 a.m. Tuesday, July 17. "At this time, the highest threat for several thunderstorms to move over the same area, potentially resulting in flash flooding, is across the flash flood watch area.
"Similarly the environment is conducive to a few strong to severe thunderstorms developing near the NYC metro and points north and west this afternoon, with potential for a more organized line of thunderstorms moving through much of the region late this afternoon into early evening with locally strong to damaging wind gusts," Vaz said.
Vaz said that as thunderstorms develop or move into the region this afternoon into this evening that "flash flood and/or severe thunderstorm warnings will be issued if a significant threat to life and/or property develops from flooding or damaging winds."
The weather service put southwestern Connecticut as a "slight risk" of flash flooding and described the following scenarios below:
  • Rainfall rates of 1 to 2 inches/hr are possible with thunderstorms.
  • Locally torrential rainfall will lead to areas of urban and poor drainage flooding.
  • Multiple thunderstorms moving over the same area will result in flash flooding.
  • Minor flooding is also possible along quick responding rivers/streams in affected basins.

Potential hazards and impacts

The main threats associated with any severe thunderstorms will be:

  • Wind gusts up to 60 mph. This could down a few to several tree limbs, trees and powerlines and possibly cause structural damage. Scattered power outages are possible.

The graphic below highlights the approximate location and level of the severe weather threat this afternoon into this evening

Additional information and resources:

NWS New York Website: https://www.weather.gov/okx/

NWS New York Winter DSS Website: https://www.weather.gov/okx/emnew_winter

NWS New York Summer DSS Website: https://www.weather.gov/okx/emnew_summer

"This will be the only briefing for this event, unless a significant change in forecast conditions warrants," Vaz wrote.

"If you have any questions in the interim or need additional information, please do not hesitate to contact us. We can be reached by phone at 631-924-0383 or  reach us by email at okx.operations@noaa.gov or through NWSChat."