California to Suffer Potential Flash Flooding As Pacific Storm Brings Heavy Rainfall to West Coast

Southern California and other parts of the country will see excessive rainfall late tonight and tomorrow, resulting in flash flooding.

According to the short-range forecast by the National Weather Service (NWS), a weather system that is currently over the Pacific Ocean will move southward throughout today. As the cold front approaches the west coast, heavier rain—with the potential for thunder and lightning—is forecast. The Weather Prediction Center (WPC) lists a "slight risk" for excessive rainfall tomorrow.

Further north, a frost advisory is in effect until 10:00 a.m. PT for Curry County coast in South Oregon, affecting cities like Coos Bay, Reedsport, Bandon and Coquille. NWS says that temperatures are in the range of 30 to 36 F, which will result in frost.

The forecast map, issued March 9, shows two weather systems bringing heavy rainfall, snowfall and frost to the U.S. NOAA

Heavy snow for Northern Maine

Toward the middle of the country, a frontal boundary over the Plains and Upper Midwest is continuing to move southward and eastward from today, according to NWS. Rain is currently falling over the middle of the Mississippi Valley, with an area of low pressure affecting Kansas and Iowa today and then Michigan tomorrow.

For Maine, the eastern portion of the front will produce light to moderate snow due to colder air, with some mixed precipitation south to southeast of the state. Slick conditions have also been forecast by the NWS.

Flood Warnings for Midwest and South East

States such as South Dakota, Texas and Alabama are under flood warnings for the next 24 hours. According to NWS, rivers such as Mud Creek (SD), Sioux Falls (SD), Dobbins Creek (WI), Coosa River (GA) and Canoochee River (SC) are under flood warnings, which are in effect until further notice.

In South Dakota, NWS Aberdeen has issued a warning for Mud Creek near Rauville due to the forecast precipitation over the next 24 hours. According to the alert, the stage at midnight today stood at 9.1 feet—the flood stage is 9 feet. Sixmile Creek near Brookings is also under a flood warning—at 10:00 p.m. local time yesterday, the stage was recorded higher than the flood stage.

In Wisconsin, runoff from melting snow is causing Dobbins Creek, at Austin, to rise rapidly, with additional runoff expected into this morning. The alert advises that if anyone lives in a threatened area such as this one, they need to be alert for high or rising water and be ready to move to higher ground if necessary. The warning is in effect until tomorrow morning—at 9:30 p.m. yesterday the stage was 11.2 feet, the flood stage is 11.5 feet, with levels expected to rise to 12.5 feet by this morning.

The Coosa River near Plant Hammond, Georgia, is experiencing minor flooding that is forecast to continue. Yesterday evening, the river stage was at 571.5 feet—the flood stage is 570 feet. It is expected minor flooding will continue into the woodlands as water levels rise, affecting fields and pastures along the river upstream and downstream, according to the NWS. A small portion of an access road near and under the Georgia Highway 100 bridge will be under 2 feet of water.

In the same state, a flood warning is also in effect for the Little Ocmulgee River near Scotland until further notice. According to NWS, the stage was last reported to be sitting at 12.6 feet last night, with minor flooding already occurring for wooded wetlands near Highway 149—flood stage is 12 feet.

In Louisianna and Texas, several rivers are under flood warnings. The Atchafalaya River at Morgan City has passed the flood stage of 6 feet and was last recorded at 7 feet last night. At this level, buildings at the foot of Ann Street on the riverside of the floodwall will flood as water overtops the Rio Oil Company dock, according to the NWS. Buildings on the riverside of the Berwick floodwall will also flood with river traffic restrictions strictly enforced. There is also a risk of backwater flooding impacting areas around Lake Palourde and Stephensville.

The Sabine River near Deweyville is reporting minor flooding, which is expected for the next several days. It is forecast that minor lowland flooding will occur. The Calcasieu River near Glenmora is currently sitting just over the flood stage at 12.1 feet, based on overnight forecasts from NWS, with roads upstream from Glenmora covered in water and are potentially subject to closing. Flooding of forested areas near the river is also forecast to occur.

Mobile River at Barry Steam Plant, Alabama—affecting Baldwin and Mobile Counties—is expected to flood due to significant rises along the river from heavy rainfall. While there is no flooding at the moment, the NWS warns it is forecast. The Tombigbee River at Demopolis Lock and Dam is currently flooding but expected to slowly fall over the next several days.

Further warnings will be issued this morning—for more information visit the NWS's Flood Warning page or listen to NWS radio for updates. For safety advice, visit the NWS safety page and to see whether insurance is required, visit FEMA's flood map.