Flood Watch

Redondo Beach, WA

Day 1: 2024-09-28

CATEGORY 2

WHAT Minor coastal flooding expected. Possible inundation of up to 1 foot above ground level near shorelines and low-lying areas.

*WHEN From 01:00 AM to 03:00 AM PST and from 03:00 PM to 05:00 PM PST.

IMPACTS Minor flooding of low-lying areas, parks, and roads. Isolated road closures possible.

ADDITIONAL DETAILS...

On 2024-09-28, the high tide at 01:06 AM is expected to reach a height of approximately 16.422 feet with a barometric pressure of 1012.38 hPa. The second high tide at 03:18 PM will reach around 18.963 feet with a barometric pressure of 1013.88 hPa. These conditions are similar to the Category 1 event on 03/02/2024 but with slightly higher tide levels. However, the barometric pressure remains well above the critical threshold of 992.8 hPa, reducing the likelihood of significant flooding.

Day 2: 2024-09-29

CATEGORY 3

WHAT Moderate coastal flooding expected. Possible inundation of up to 2 feet above ground level near shorelines and low-lying areas.

WHEN From 02:00 AM to 04:00 AM PST and from 03:30 PM to 05:30 PM PST.

IMPACTS Moderate flooding of low-lying areas, parks, and roads. Some road closures possible.

ADDITIONAL DETAILS...

On 2024-09-29, the high tide at 02:12 AM is expected to reach a height of approximately 16.753 feet with a barometric pressure of 1013.06 hPa. The second high tide at 03:42 PM will reach around 18.906 feet with a barometric pressure of 1005.16 hPa. The lower barometric pressure during the afternoon high tide increases the risk of flooding compared to Day 1, making it similar to the Category 3 event on 12/27/2023 but with slightly lower tide levels.

Day 3: 2024-09-30

CATEGORY 2

WHAT Minor coastal flooding expected. Possible inundation of up to 1 foot above ground level near shorelines and low-lying areas.

WHEN From 03:00 AM to 05:00 AM PST and from 04:00 PM to 06:00 PM PST.

IMPACTS Minor flooding of low-lying areas, parks, and roads. Isolated road closures possible.

ADDITIONAL DETAILS...

On 2024-09-30, the high tide at 03:06 AM is expected to reach a height of approximately 17.103 feet with a barometric pressure of 1017.89 hPa. The second high tide at 04:00 PM will reach around 18.813 feet with a barometric pressure of 1017.30 hPa. Despite the higher tide levels, the significantly higher barometric pressure reduces the likelihood of severe flooding, making it similar to the Category 2 event on Day 1.

PRECAUTIONARY/PREPAREDNESS ACTIONS...

You should monitor later forecasts and be alert for possible Flood Warnings. Those living in areas prone to flooding should be prepared to take action should flooding develop.

Forecast Reasoning:

Step-by-Step Analysis:

  1. Assess Barometric Pressure:
  2. For all three days, the barometric pressure remains well above the critical threshold of ~992 hPa.

  3. The lowest pressure observed is on Day 2 (1005.16 hPa), which still does not indicate severe weather conditions.

  4. Evaluate Tide Height:

  5. Tide heights range from approximately ~16 feet to ~18 feet.

  6. These heights are significant but not as extreme as historical Category 4 or Category 5 events which had tides over ~21 feet.

  7. Consider Wind Direction and Speed:

  8. Wind data is not provided in detail for these days; however, historical data suggests that wind direction from W/NW can exacerbate conditions.

  9. Given no extreme wind conditions are reported, this factor is considered less critical for this analysis.

  10. Integrate NOAA High Tide Flooding Likelihood:

  11. NOAA's flood likelihood for these dates is low (0%), indicating minimal risk based on their analysis.

  12. This supports the categorization as lower-risk events (Categories 2 and possibly Category 3).

  13. Synthesize Information and Forecast Flood Category:

  14. Combining all factors (high barometric pressure, moderate tide heights, low NOAA flood likelihood), Days 1 and Day3 are categorized as Category2 events.
  15. Day2 has slightly lower pressure and higher tides compared to other days but still does not meet criteria for severe flooding (Category4+), thus categorized as Category3.

This methodical approach ensures an accurate assessment based on provided data while emphasizing safety and preparedness for potential flood risks in Redondo Beach, WA.