National Weather Service extends flood watch

Expect rainy, overcast conditions through Saturday

Author: Blake Mathews, Weather producer, meteorologist, bmathews@wjxt.com
Published On: May 02 2013 06:43:28 PM EDT   Updated On: May 03 2013 10:38:45 AM EDT
Flood watch issued for Jacksonville area
JACKSONVILLE, Fla. -

Friday has been declared a Weather Authority Alert Day. Moderate to heavy rainfall continues to fall across the majority of the viewing area which prompted the National Weather Service to issue a Flood Watch for the entire area until Saturday morning.

It has been raining for more than 24 hours. Rainfall amounts have ranged from just over an inch near Brunswick to over 13 inches near World Golf Village. Due to excessive rainfall, Flash Flood Warnings have been issued for many of the counties in Florida with St. Johns county being the hardest hit.

Significant flooding has been observed at McCoys Creek, Hogan's Creek in Duval County. Residents living along lower portions of the aforementioned creeks and other tributaries to the St. Johns River should continue monitor water levees for the next 24 hours.

The computer models continue to be very bullish on the amount of rainfall expected across the area. The Global Forecast System (GFS) shows between an inch and a half more for Jacksonville to as much as 7.32 inches down in Palm Coast... that's in addition to what has already been observed. The RPM model is a bit more outlandish with rainfall showing between 5.86 inches in Jacksonville to as much as 6.10 inches in Palm Coast with lighter amounts in Georgia. Either way, any additional rainfall we receive will only exacerbate the flooding issues already observed.

Very strong on-shore winds in the range of 30 to 40 mph have slowed the rate of drainage of the St. Johns River which has attributed to Flooding of coastal regions. Also adding to the headache, a High Surf Advisory has been issued for the entire coast of northeast Florida and southeast Georgia through Friday night with breakers running 5 to 7 feet. This has also lead to a high risk of life-threatening rip currents.

The reason for the excessive rainfall is thanks in part to what we call a ''Rex Block.'' There is a strong area of low-pressure (which brought May snowfall to Tulsa on Thursday) that is stalled out over the south that continues to draw in copious amounts of rainfall. The pattern is not expected to break down until Sunday. Until then, expect high chances of rain in your forecast.