Why all the street flooding yesterday? More rain on the way!
November 5, 2023
Sunday:What's up with the street flooding yesterday (Saturday)? First, let me update you on the weather real quick. Periods of rain and showers through Tuesday with an isolated thunderstorm possible. Winds can gust to around 25 mph at times. Total rainfall 3/4"-1.25", most of this occurring later this evening through Monday (doesn't it feel humid out?). Dry Wednesday and most of Thursday. Rain returns Thursday evening or night (looks like less than 1/2"). Saturday might be dry then more rain Sunday into the following week. Around Wed Nov 15 we might start getting colder storms with lower snow levels than what we've been having.
OK, so here's what happened with yesterday's street flooding:
Things aligned just right: plenty of moisture available, heavy showers / thunderstorm forming over Cottage Grove, time of year when leaves clogging storm drains, everyone doing the rain dance at the same time.
Moisture: Scroll down and check out the satellite image showing the moisture being pumped into the region as whites and greens.
Heavy showers/thunderstorm: Play the radar GIF below, notice the little blips of yellow suddenly pop up over CG. These were heavy showers and a thunderstorm that caused heavy rain to fall in a short period of time due to plenty of available moisture.
Note about Radar: The radar that best covers our area is in Medford, up on Mt Ashland at about 7500'. Unfortunately, Cottage Grove is in a blind spot in that the radar has difficulty seeing anything below about 10,000 feet by the time the radar beam reaches here (due to the curvature of the earth). If you're a radar watcher, you've probably noticed that your radar app shows no rain falling when it is actually raining.
Rainfall 3pm-6pm Saturday in and immediately around Cottage Grove ranged from 1/2" to 1.28". Heaviest occurring on the east side and southeast side, which is where the heavier showers peaked in intensity. This overwhelmed storm drains that were already having difficulty with all the leaves; everything aligned just right for water having nowhere to drain without obstructions.