Enhanced Risk for Severe Thunderstorms Across the Upper Midwest; Flash Flooding Possible from the Upper Midwest to Southern Plains and Desert Southwest Through Friday

Portions of the Upper Midwest will see an increased threat for severe thunderstorms through this evening, with a few strong tornadoes possible. The same region remains on alert for additional flash flood concerns. Heavy rainfall may lead to flash flooding across the Desert Southwest today, and Southern Plains by Friday. Finally, Major-to-record river flooding continues across the Carolinas.
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Last Update: 850 AM PDT Thu Sep 20 2018

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19NM W San Francisco CA

Marine Zone Forecast


Synopsis: PZZ500-210430- 850 AM PDT Thu Sep 20 2018 .Synopsis for the Central California Coast and Bays Including the Monterey Bay...Greater Farallones...and Cordell Bank National Marine Sanctuaries... Breezy and gusty northwesterly winds will persist today with high pressure over the eastern Pacific and a thermal trough over California. This will likely produce steep waves over the northern offshore waters through today. Winds will diminish on Friday as the high pressure weakens. $$

Today
NW winds 10 to 20 kt with gusts up to 25 kt... Diminishing to 5 to 15 kt this afternoon. Wind waves 3 to 5 ft. NW swell 3 to 4 ft at 8 seconds.
Tonight
NW winds 5 to 15 kt. Wind waves 3 to 4 ft. NW swell around 3 ft at 8 seconds. Patchy fog.
Fri
SW winds up to 10 kt. Wind waves 2 ft or less. NW swell 3 to 4 ft at 8 seconds. Patchy fog.
Fri Night
W winds 5 to 10 kt. Wind waves 2 ft or less. NW swell around 3 ft at 8 seconds.
Sat
W winds up to 10 kt. Wind waves 2 ft or less. NW swell around 3 ft at 8 seconds.
Sat Night
NW winds 10 to 20 kt with gusts up to 30 kt. Wind waves 3 to 4 ft. NW swell 3 to 5 ft at 9 seconds.
Sun
NW winds 10 to 20 kt with gusts up to 25 kt. Wind waves 3 to 4 ft. NW swell 3 to 5 ft.
Mon
NW winds up to 10 kt. Wind waves 2 ft or less. NW swell 3 to 6 ft. .....san francisco bar/fourfathom bank forecast..... in the deep water channel...combined seas 5 to 7 ft with a dominant period of 10 seconds. across the bar...combined seas 6 to 8 ft with a dominant period of 10 seconds. Maximum ebb current of 1.7 knots at 01:25 pm thursday and 1.7 knots at 01:37 am friday.

.....SAN FRANCISCO BAR/FOURFATHOM BANK FORECAST..... IN THE DEEP WATER CHANNEL...Combined seas 5 to 7 ft with a dominant period of 10 seconds. ACROSS THE BAR...Combined seas 6 to 8 ft with a dominant period of 10 seconds. Maximum ebb current of 1.7 knots at 01:25 PM Thursday and 1.7 knots at 01:37 AM Friday.
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ABOUT THIS FORECAST

Last Update: 850 AM PDT Thu Sep 20 2018
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