WeatherWatcher: Weekly Weather, Last week's lightning

• Forecast
• Last week's highlights
• Last week's data

Forecast: Summer is returning this week with sunny skies and highs in the upper 70's and low 80's. Our nice weather will be pretty much consistent until the Friday to Saturday time frame when a stronger marine air flow will take over and bring is mostly cloudy days and cooler air. Showers may be possible later into Saturday and Sunday.

Last week's highlights: We had some very significant thunderstorm activity spread over 2 days last week. Due to an area of low pressure off the coast of Oregon we had a humid air flow all week long, with convection development starting Wednesday evening as the low pressure system moved inland. We had thunderstorms Thursday early morning (1-2am), mid Thursday morning, with a break in the afternoon, then about 8-9pm the thunderstorms were back with the most intense activity we've seen in several years. The activity lasted until 1-2am, and we had yet another cell move over us around 9-10am Friday morning.

Rain associated with these storms was heavy at times bringing in a total rainfall last week of 2.14 inches. 0.71 inches of rain fell in a 1 hour period from 8-9am Thursday morning. The average total rainfall for the month of September for the last 3 years has been about 2.77 inches, so we are already very close to the normal total monthly rainfall for September. Currently September 2010 holds the station record at 6.01 inches of rain.

Last week's data:

High temperature: 84.4°F (Sunday)

Low temperature: 55.0°F (Saturday)

Rainiest day: 1.10 inches (Friday)

Total rainfall: 2.14 inches

Warmest day: 67.3°F (Monday)

Coldest day: 59.9°F (Thursday)

Average temperature: 63.5°F (3.3°F above average)

Station historic average for this week: 60.2°F

Daily Average temperature compared to historic average.

Warmest and coldest days are based on average temperature of the entire day, starting at midnight. All other averages are based on the whole week, starting Saturday morning at midnight. All weather data unless otherwise noted is sourced from Carl's weather station located in the Echo Lake neighborhood of Shoreline, Washington. For up to the minute weather conditions and historic data, as well as links to weather information and resources, check out my page.

Follow me on Twitter: @SWeatherWatcher for any updates on weather events approaching our area.