Heavy rain is forecast to continue Wednesday as the National Weather Service expanded a Flood Watch to include King and Pierce counties that could produce flooding on some area rivers.
According to the National Weather Service:
HEAVY RAIN OVER THE SOUTHWEST SLOPES OF CASCADE MOUNTAINS TODAY THROUGH WEDNESDAY COULD DRIVE THE MOST FLOOD-PRONE RIVERS OF THE NORTH CASCADES TO JUST ABOVE FLOOD STAGE. STORM TOTAL RAINFALL THROUGH WEDNESDAY WILL LIKELY RANGE FROM 2 TO 4 INCHES...WITH THE SNOW LEVEL AROUND 7000 TO 8000 FEET. ROUGHLY 1 TO 2 INCHES OF RAIN IS EXPECTED OVER THE LOWLANDS.
* THE MOST FLOOD-PRONE RIVERS IN THE WATCH AREA INCLUDE THE PUYALLUP RIVER NEAR ORTING AND THE WHITE RIVER BELOW MUD DAM. IF ANY OF THESE RIVERS DO FLOOD...IT WILL PROBABLY BE RELATIVELY MINOR. THE RAINFALL IN THE LOWLANDS WILL ALSO LIKELY CAUSE STREET FLOODING IN POORLY DRAINED AREAS OR WHERE STORM DRAINS ARE COVERED BY LEAVES. PRECAUTIONARY/PREPAREDNESS ACTIONS... A FLOOD WATCH MEANS CONDITIONS ARE FAVORABLE FOR FLOODING BUT FLOODING IS NOT IMMINENT OR OCCURRING. MONITOR THE LATEST FORECASTS FROM THE NATIONAL WEATHER SERVICE AND BE READY TO ACT QUICKLY IF FLOODING IS OBSERVED OR A WARNING IS ISSUED.
The Halloween forecast for Mercer Island is 100 percent chance of rain, a high near 59 and south wind from 8-13 mph, according to the National Weather Service Seattle.
Earlier on Monday, the NWS issued the following Special Weather Statement:
A WET PACIFIC FRONTAL SYSTEM WILL BRING ADDITIONAL RAIN TO THE LOWLANDS TONIGHT INTO WEDNESDAY...
MOIST SOUTHWEST FLOW DIRECTED INTO WESTERN WASHINGTON WILL KEEP STEADY RAIN GOING ACROSS THE ENTIRE AREA TONIGHT INTO WEDNESDAY MORNING. UP TO AN INCH OF RAIN HAS ALREADY FALLEN IN SOME PARTS OF THE LOWLANDS TODAY. ANOTHER 1 TO LOCALLY 2 INCHES ARE POSSIBLE BY WEDNESDAY AFTERNOON.
MINOR URBAN AND SMALL STREAM FLOODING IS POSSIBLE OVER THE NEXT 24 HOURS DUE TO THE COMBINATION OF STEADY RAIN AND LEAVES CLOGGING DRAINS. THIS MAY CAUSE PONDING IN INTERSECTIONS...UNDERPASSES...AND LOW-LYING STREETS. EXERCISE CAUTIONS WHILE DRIVING.
Real-time river level information is available online at http://www.kingcounty.gov/flood.
Updated information on flooding will also be posted on the King County website at www.kingcounty.gov, and via RPIN, the area's regional website at http://www.rpin.org. A recorded flood-information hotline is also updated each hour for citizens wanting information on flood conditions. The number is 206-296-8200 or 1-800-945-9263.
Citizens who need help interpreting flood information should call 206-296-4535 or 1-800-768-7932. Problems on County maintained roads can be reported by calling 206-296-8100 or 1-800-KC-ROADS.